q_id
stringlengths 5
6
| title
stringlengths 3
296
| selftext
stringlengths 0
34k
| document
stringclasses 1
value | subreddit
stringclasses 1
value | url
stringlengths 4
110
| answers
dict | title_urls
sequence | selftext_urls
sequence | answers_urls
sequence |
|---|---|---|---|---|---|---|---|---|---|
6d5hoq | how can bugs that can't eat survive as a species | [deleted] | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/6d5hoq/eli5_how_can_bugs_that_cant_eat_survive_as_a/ | {
"a_id": [
"di00m13"
],
"score": [
5
],
"text": [
"The adult mayflies don't eat, but their pupal and larval stages do. So they eat while the grow, then they develop into adults and just mate, lay eggs and die."
]
} | [] | [] | [
[]
] |
|
9l3j89 | how do mri machines work? | I've tried reading the Wikipedia article and get lost having to read a separate article on _every_ term used in the info. | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/9l3j89/eli5_how_do_mri_machines_work/ | {
"a_id": [
"e73qyhf",
"e73ric3",
"e73rr9w",
"e73xrir",
"e742q0q",
"e742uh2",
"e7434dl",
"e744yzj",
"e74bgww",
"e74elr6",
"e74grx9",
"e74jl4b",
"e74sb7k",
"e74trtx",
"e74xt5n",
"e74yjom"
],
"score": [
4,
6,
503,
66,
3,
3,
2,
8,
4,
18,
2,
2,
2,
2,
2,
2
],
"text": [
"The simplest explanation is that we know magnetic lines travel in a specific path. \nIf you control the magnetic source very very carefully and can measure any changes in its direction and strength very very accurately you can then use this to detect different things. \n\nIt gets REALLY complicated but the general gist is we know what’s in a human body and how each thing acts (muscle, bone, etc) with a magnetic field. This allows us to pass magnetic lines through a person and get an image of what is where to a fairly accurate degree. \n\nThat’s as best “like I’m five” I got for you. ",
"This is a fairly complex subject, which requires many years of education in Physics to properly understand. So the explanation given here is not wholly accurate.\n\nElectrons have a quantum-mechanical property known as \"spin\". This spin can be positive or negative (think of it as spinning left vs. right).\n\nNormally, this spin is undetectable - it doesn't change any of the measureable properties of the electron.\n\nWhen an electron is \"excited\" (meaning it has more energy than it's lowest level state), it will eventually \"de-excite\" and give off one or more photons (bits of light). These photons have very specific wavelengths, so you can measure the light and know exactly what the excited state was and how it transitioned back to its low state.\n\nYou may have seen this yourself - have you ever seen the chemicals that you can throw into fire to change its colour? The energy from the fire excites the atoms in the chemical, and these chemicals were chosen because some of the bits of light given off are in the visible spectrum - so you can see the de-excitation.\n\nNow what does this mean for MRIs, and why does electron spin matter?\n\nWhen you apply a strong magnetic field, the energy levels of the electrons change slightly. One spin will have more energy, one will have less. This in turn changes the wavelength of the emitted light.\n\nThe handwavey part here is that the MRI is able to combine all of this information together to be able to \"see\" what materials are where in your body. And because it uses powerful magnetic fields, metallic substances will shift and move and heat up as the fields change, which is why they're always so careful to make sure you don't go in with bits of metal, especially inside your body.\n\nEDIT: I've got this partly wrong entirely. MRIs work on the proton spins of the hydrogen atoms of the water molecules in your body, not the electrons. It still works based on the spins of the particles, but the excitation and emission here is flipping the spins to all be the \"same\", and the de-excitation is when the spins flip back.",
"Really oversimplified explanation:\n\n1. suspend body in really strong magnetic field, forces water molecules to line themselves up in specific direction\n2. at same time, zap water molecules in body with a radio wave, causes them to wiggle against magnetic field direction\n3. wiggling water molecules give off their own radio waves, slightly different for each kind of tissue. Record it all & use computer to reconstruct 3D picture of it.",
"You know how a spinning top wants to be straight up? Even when you push it (a little) it is happiest when pointing straight upwards. The top even makes a little \"woosh\" sound when going back up again.\n\nWell your body is full of these tiny spinning tops of different sizes that are happily spinning around.\n\nYou can make these spinning tops spin the same way using a really big magnet (they now all point the same way and spin at the same speed). Using a radio we can give some of the tops a little push and listen to the tiny \"woosh\" sounds the tops make to hear where they are located.\n\nEdit:\n\nIf you want to delve a little deeper take a look at this (short) [book: MRI made easy](_URL_0_) (link immediately downloads). It's written with non-technical people in mind and very complete and understandable given how insanely difficult the subject is.",
"To add to the physics explanations, the reason it is so useful to visualize soft tissue is that it is exploiting the spin of the hydrogen atom and two very abundant substances in the body are hydrogen rich: fat and water. Different imaging sequences use different timing to make different types of tissue to appear different. While X-ray and CT imaging are looking at density of tissue, MRI can characterize tissue based on the appearance on each sequence. Inflammation shows as water on imaging, think of swelling. ",
"Everything consists of atoms, including you. Each atom in turn consists of a nucleus and some electrons flying around it.\n\nIt turns out that many (but not all) atomic nuclei are actually magnetic, you can really think of them as absurdly tiny, absurdly weak bar magnets. The strength of this magnet depends on the type of atomic nucleus. The second-strongest nuclear magnets are common hydrogen nuclei. This is convenient because water contains hydrogen, and your body is mostly water.\n\nUnfortunately, nuclear magnetism is (almost always) too weak to just measure with a magnetic field sensor, we have to get more clever than that and use magnetic resonance.\n\nIf you place a magnet in a strong magnetic field, it will try to align itself along the magnetic field. Now suppose this magnet can rotate freely in 3D, imagine it's mounted on gyroscope, and we misalign the magnet. The torque on magnet due to the magnetic field will cause it to rotate (\"precess\") about the magnetic field. The frequency of this rotation is equal to the strength of the magnet times that of the magnetic field - this is called nuclear magnetic resonance (NMR). There is very little friction affecting this rotation, it typically lasts for around one second.\n\nNow we have a rotating magnet, like you do in a bicycle dynamo or a generator. This means that if we wrap a coil of wire around that magnet, it will induce an oscillating electric current! We can measure this current using some electronics - this is the MRI receiver.\n\nSince we know the magnetic moment of a hydrogen nucleus, the frequency of this signal tells us the magnetic field at the position of the nucleus. The amplitude of the signal at each frequency tells us how many hydrogen nuclei experience this same magnetic field.\n\nBut how do we misalign the magnets in the first place? That's easy, we \"hit\" it with an additional, weak magnetic field that oscillates at the NMR frequency - this is the MRI transmitter. The best picture for driving a resonator at its resonance frequency I have is imagine a child on a swing. You can get huge swings by giving it gentle periodic pushes at the right frequency.\n\nOk, so we can measure how many nuclei experience which magnetic field strength, how does this help us? Well, the largest part of an MRI machine is actually to control a strong magnetic field, and magnetic field gradients (i.e. to make the field slightly stronger in one direction and slightly weaker in the opposite direction). This means that the NMR frequency spectrum alone can actually be used as a one-dimensional image in the direction of the gradient!\n\nBut how do we get 3D images? We have to get clever with turning the three gradients and the MRI transmitter and receiver on and off at the correct time. For example, you can do \"slice selection\" along the z-axis by first turning on a strong gradient along z and then pulsing the transmitter at a specific frequency - then you only \"excite\" nuclei whose NMR frequency matches the transmitter frequency, i.e. those in a narrow slice perpendicular to the z-axis.\n\nWhile the nuclei are still rotating, you turn off the z-gradient and you turn on a weak x-gradient and turn on the receiver. Remember, you have a whole second to do this, so plenty of time. Now, the frequency of the NMR signal corresponds to the position along the x-axis. This is called frequency-encoding (along x).\n\nThis gives you a two-dimensional image already, and there are more tricks with gradients to give you a three-dimensional image. Clever people have figured out how to time gradients, transmitter, and receiver to image more complex things like fluid flow.\n\nTo increase the image contrast, we can make use of the fact that the time for which the nucleus precesses is different in different tissues. So by adjusting our timing sequence, we can suppress or enhance signal from different types of tissue. By using a \"contrast agent\", which for MRI means a strong, molecule-sized magnet, we can affect this timing as well.",
"^(we use multiple magnets in different directions to excite protons in a selected slice and cause them to precess or “rotate”— though they aren’t physically rotating. we can then use radio coils to detect the signal these rotating protons give off and a computer to reconstruct the image.)",
"If you put a really powerful magnet on something that has water, that water will act like a compass, and point to the direction of the magnet. Then you use another magnet to push that water, it causes it to act like a spinning top, and will rotate. With enough water spinning together, it behaves like a magnet itself, and you can read how strong of a magnet it is. Now next to different things, water rotates either quickly or slowly, that allows us to distinguish between one thing to another. That encompasses what's called NMR (Nuclear Magnetic Resonance).\n\nMRI is taking it one step further. We want only a small set of that water to do what we said, so we use another magnet to choose only part of it. How that's achieved is a bit more than 5 year old level, but basically we listen in to only what we want each time. We get a really distorted picture that we need to understand how to rebuild into a picture that you see. It's not like X-Ray where you get the entire picture in one go.",
"yes its a small miracle which has to occur each time we get a \"routine\" mri for headaches or something. Scientific insights from multiple, at least 4, separate nobel prizes went into enabling us to look with beautiful accuracy through half an inch of solid bone at your brain in exquisite detail all without any ionizing radiation!",
"Here is my ELI5 of this, because I think that the math of how this works is simply beautiful.\n\nYou are made up of atoms. All different kinds of atoms. Lots of these atoms are hydrogen. Hydrogen is a special atom cuz it is so simple. It acts like a spinning magnet cuz it is so simple.\n\nNow normally, all your hydrogen atoms are pointed random directions, so you aren't magnetic. But if we put you in a strong enough magnetic field, the field it'll push and pull on these magnets. They line up. It makes all the atoms point up or down. But half of them are pointed up, and half of them are pointed down. So while they are lined up, they cancel each other out, so they still aren't magnetic.\n\nHowever, since they are lined up now, we can \"wack\" them with another magnetic pulse. This turns all the magnets to the side. Suddenly they are all pointed in the same direction! You become briefly magnetic, and we can listen to that with an antenna.\n\nHowever we only wacked the atoms, the big strong magnetic field still wants all the atoms to line up. And our atoms are still spinning, just like a top. So, just like a spinning top after getting wacked, the atoms rock around as they line up again. This causes them to ring. Because all the atoms are so simple, they all spin in approximate unison. If you are next to your neighbors you can sing louder and longer than someone by themselves. This gives us a weird coral note. By wack again in the middle of the note, we can get other notes, sort of like playing the song at a faster tempted. Sometimes we have to wack really fast (this is what makes all the noises in the MRI machine).\n\nOnce we get a picture of all the notes over time, and with different pulse intervals, we get a chart of the chorus that your body made. By literally looking at the magnitude of the notes Harmony we can put together the picture of you!",
"The original name for MRI is Nuclear Magnetic Resonance. You are made up of organic molecules (carbon molecules). Organic molecules have hydrogen atoms bonded to them. These hydrogen atoms are also called protons. The protons spins “point” in a particular direction. Each proton spins in a relatively different direction depending how many other protons or carbon atoms are close to it. \n\nWhen you apply a strong magnetic field to the organic material or body the protons spins all line up with the magnetic field. When you turn off the magnetic field the protons relax back to their original state. When an atomic particle relaxes to its original state it emits some sort of energy. Protons emit radio waves when returning to a relaxed state from an induced magnetic field. \n\nThe strong magnetic field is rapidly turned on and off causing the protons to resonate radio waves. Since each proton has a slightly different original spin direction each proton gives off or resonates a slightly different radio wave. \n\nThe emitted radio waves can be mathematically transformed into a picture a person can more easily interpret. ",
"A lot of people are talking about water molecules, but I haven't seen anyone mention this, so here's my actual 5 year old explanation:\n\nHumans are made of mostly water, but the squishier parts have more water in them than the hard parts. We use a magnet to get all of the water molecules to point the same way so that we can see them, then take a picture. The white part of the picture is where there's the most water, which is how we can see the different things inside of us.",
"It stands for Magic Resonance Imaging, it was created by a wizard in 1942. It's just magic and that's that.",
"If you want more detailed info, there is a course on Coursera just about this [MRI Fundamentals](_URL_0_)",
"Who was smart enough to even contemplate this?",
"I'm a bit late on this, but I'll give this a shot in case you still want to know more. As a disclaimer, I'm a neuroscientist, not a physicist, so I probably can't give as in depth an explanation as some would like.\n\nMagnetic resonance imaging, or MRI, is a technique that is often used to give high-res images of soft tissues. MRI fundamentally works by taking advantage of the fact that atoms that make up organic tissue have magnetic properties. One kind of atom that is common throughout the brain (all organic tissue really) is hydrogen. The proton in hydrogen is constantly in motion, spinning around its axis, kind of like how the Earth rotates. This motion creates a very tiny magnetic field. Normally, the direction of the axis of all the protons in tissues are randomly distributed, since Earth's magnetic field is too weak to influence them. When you use an MRI, you create a powerful magnetic field-- gravitational forces on Earth create a magnetic field of about 0.001 teslas in strength, an MRI scanner can create magnetic fields from 0.5-1.5 tesla. So when a person is put into the magnetic field generated by an MRI machine, a lot of their protons become oriented in such a way that their principle axis point parallel to the magnetic force generated by the MRI machine. Then, you pass radio waves through the magnetized regions. Radio waves have energy, and as the protons absorb the energy, their orientations are changed in a particular, predictable way. When you turn the radio waves off, the absorbed energy is released and the protons will \"snap\" back towards the orientation of the magnetic field. When all the protons snap back together, they produce energy signals that can be detected by specialized detectors around the head of the patient. If you systematically measure the signals throughout the 3D volume of the head, an MRI signal can construct an image based on the distribution of the protons and other magnetic images in the tissue. Since he hydrogen proton distribution in the brain is mostly determined by where you can find water, MRI can distinguish easily between grey matter, white matter, ventricles, and fiber tracts.\n\nMRI provides a significantly higher resolution image than another common structural analysis technique, computed tomography, or CT . This is because there are much more protons in grey matter than white matter. So with MRI, it is easy to see individual folds in the brain. It can also see structures smaller than 1mm, allowing you to see small structures deep in the brain, like the mammillary bodies or the superior colliculus."
]
} | [] | [] | [
[],
[],
[],
[
"http://www.stat.columbia.edu/~martin/Tools/MRI_Made_Easy.pdf"
],
[],
[],
[],
[],
[],
[],
[],
[],
[],
[
"https://www.coursera.org/learn/mri-fundamentals/home/welcome"
],
[],
[]
] |
|
723y5k | what causes the testes to produce more sperm? how does the body know not to produce more when they are full? | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/723y5k/eli5_what_causes_the_testes_to_produce_more_sperm/ | {
"a_id": [
"dnfoyut",
"dnfpvco",
"dnfxa6y",
"dng8i72"
],
"score": [
79,
5,
2,
5
],
"text": [
"So, a lot of guys have this idea that there is a finite amount of room in your testes and that your body can only produce a limited amount of sperm.\n\nIn truth, your body is almost always producing sperm. While yes there is a finite amount of room in your testes for sperm to be created, in practice it is near impossible to ever reach this cap. One, because your testes can expand slightly, vastly increasing sperm storage. Two, because the amount of sperm your body can actually store, even before the aformentioned enlargement, is a pretty crazily high amount. And three, because older sperm are usually broken down and 'remanufactured' into newer sperm.\n\nYour body nornally (Outside of a few diseases/nutrient deficiencies) does a pretty remarkable job of breaking down old or improperly formed sperm, absorbing the remnants, and then creating new sperm.",
"Follicle stimulating hormone (FSH) from the pituitary gland stimulates serotoli cells within the testis. These cells drive the creation of sperm (spermatogenesis). They produce a product called inhibin B which feeds back to the pituitary and decreases the amount of FSH being produced (negative feedback). This creates a balance of the hormone driving sperm production. Not so much because the testes are 'full'. \n\nWorth noting that testosterone also negatively feeds back on FSH production - thus taking exogenous testosterone will decrease not only your own bodies testosterone production but sperm production as well. ",
"Your pituitary gland secretes hormones that regulate the production of sperm.\n\nHowever, sperm are pretty much always being created (~40 million sperm per day!). If you don't ejaculate to release the sperm from the testes, your body simply breaks down older sperm OR initiates a \"wet dream\" (involuntary ejaculation) during sleep to decrease the load.",
"So if you masturbate 10 times in lets says 4 hours does the amount of sperm decrease per ejaculation. How fast is the sperm reproduced. "
]
} | [] | [] | [
[],
[],
[],
[]
] |
||
o7hva | what happen between half-life and half-life 2 ? | I read somewhere that HL2 takes place 20 years after HL1, and I know there was some war going on Between the combine and the earth, but that's basically al I know.
what's the purpose of City 17? Why is Freeman so important? what's the connection between all of this and the events of HL1?
Sorry for my bad english.
| explainlikeimfive | http://www.reddit.com/r/explainlikeimfive/comments/o7hva/eli5_what_happen_between_halflife_and_halflife_2/ | {
"a_id": [
"c3f05sq",
"c3f09b6",
"c3f0cw6",
"c3f0jhb",
"c3f0rqm",
"c3f0viv",
"c3f0wpw",
"c3f158n",
"c3f29ic",
"c3f2to7",
"c3f672w"
],
"score": [
122,
47,
31,
19,
9,
3,
2,
4,
11,
2,
2
],
"text": [
"There's a lot of good information about this that can be gleaned by examining Dr. Vance's office at Black Mesa East during HL2. Basically, the resonance cascade of HL1 got the attention of the Combine, who invaded earth shortly after Freeman was put in stasis. They defeated all of earth's military forces in 7 hours (hence, the 7 Hour War). They proceeded to subjugate humanity and begin draining earth of resources, most notably its oceans, the results of which are plainly obvious in City 17 and the surrounding coast. Cut ahead some unknown amount time (Generally agreed to be about 20 years) and Freeman returns.\n\nCity 17 is the seat of the Combine's power on Earth. It doesn't hold any particular significance than that, and in fact there are many other citadels like the one at the center of City 17 across Earth.\n\nGordon's importance isn't entirely clear yet. He's more of a symbol of human endurance against alien invaders to the rest than anything, though he's undeniably proficient with a wide variety of weapons. The G-Man's interest in him means that he probably has some other significance as well, but what that is has yet to be explained. (Though Valve has promised it will be explained more completely in the sequel)\n\nEDIT: changed HL2EP3 to \"the sequel,\" as it isn't clear at this point how exactly the sequel will be named",
" > I read somewhere that HL2 takes place 20 years after HL1\n\nSomething like that. Alyx was a little girl when the resonance cascade incident at Black Mesa happened, now she's grown up. So if you ask me, 15 years minimum.\n\nThere's a theory that the G-Man put Gordon into a [\"slow teleport\"](_URL_1_) (a teleport where time inside passes very very slowly) at the end of HL1, and then pulled him out at the beginning of HL2. That would explain why Eli (Vance, Alyx's dad) says: \"You haven't changed one iota, how do you do it?\" to Gordon when he arrives at Black Mesa East during the first parts of HL2.\n\n > I know there was some war going on Between the combine and the earth\n\nIt's been over for a *long* time at the point that HL2 starts. They called it the [\"Seven Hour War\",](_URL_3_) because that's how long it took the Combine to completely steamroll the united military forces of Earth once the portal(s) opened. There's still a tiny guerrilla resistance movement, but it's been pitifully ineffective until Gordon shows up.\n\n > What's the purpose of City 17?\n\nMultiple reasons, probably. One is to keep all the remaining humans in one place so they're easier to control. But another one just as important can be summed up in one word: Antlions.\n\n > The Portal Storms raged across the Earth, (and still do according to Marc Laidlaw) spreading Xen life forms across Earth causing the people to move into cities for protection.\n\n- _URL_0_\n\nIf you played HL2:Ep 2 you saw how the citadel had enormous ground pounders around it, constantly thumping on the bedrock to annoy the antlions and prevent them from burrowing in under the city. You see how overwhemingly deadly the antlions can be during the \"Sand Traps\" part of HL2.\n\n > Why is Freeman so important?\n\nSeveral people in the story (most importantly, the G-man) seem to believe that Gordon Freeman can tip the balance of large scale events if he's put into the right part of the situation at the right time. The [G-man explains this, obliquely, at the beginning of HL2](_URL_2_) as he pulls Gordon out of stasis and puts him on the train that's headed in to City 17.\n\n > what's the connection between all of this and the events of HL1?\n\nHL2 is the world that came about because of the events of HL1. It's just like any sequel. The events of the first one happened, and that led to what happens in the second one.",
"This might help: _URL_0_\n\nBe sure to watch them all",
"I read this guide about a year ago, it's pretty good at explaining the half life timeline _URL_0_\n\nHope this helps.",
"If these two havent beeb posted, [here](_URL_1_) here is a very, very good timeline which emcompasses the games, including Portal and other related games not labelled Half Life.\n\nAlso, this [wiki](_URL_0_) is very comprehensive.",
"This explains [everything](_URL_0_)",
"Portal 2 takes place years after Ep2 (and maybe Ep3) but i dont see how that answers your question just putting it out there...",
"Why isn't Half-Life 2 called full life?",
"I had a waking nightmare that I will settle down, get married, and have a child. When she turns five she will ask me, \"Daddy, when will Half-Life 3 come out?\"\n\nI just graduated college. Gabe, please save me from this fate.",
"[This](_URL_0_) will explain everything.",
"In a five year-old's terms?: The Resonance Cascade drew the attention of the alien empire collectively known as the Combine Empire or the Universal Union. The Combine already had the control of multiple universes of life(although the extent over their power with each universe is unknown, they might be still exploring other universes). They came to earth through the same quantum rips the Nihilanth's forces used. It should be noted here that the Combine are probably interested in the earths water and human teleportation technology, they've got us outpaced in almost everything else. Humanity was still defending itself from the forces of Xen and Race X(who only appeared in isolated pockets). Most humans moved into large walled cities a few months later. The Combine found earthlings huddled together in cramped hastily built slums and took the advantage, started a war called the \"7 Hour War\". It probably might have lated **9** hours except that Doctor Breen, Black Mesa's old administrator recognized the danger Humanity was in. Presumably using ties with the government Breen made contact with the Combine and surrendered, his motion backed up by the government presumably. The Combine turned humanity into a slave race, set up the Suppression Field so that humans couldn't reproduce and then set us to work draining the oceans and harvesting minerals presumably. The Overwatch was set up as a branch of human-Combine super soldiers to keep \"peace\" and keep their new found slaves safe from the aliens still left from the Resonance Cascade. Enter Doctor Freeman and you've got Half-Life 2."
]
} | [] | [] | [
[],
[
"http://half-life.wikia.com/wiki/Seven_Hour_War#Battle",
"http://www.halflife2.net/forums/archive/index.php/t-85236.html",
"http://www.youtube.com/watch?v=mRtT4HHQef0",
"http://half-life.wikia.com/wiki/Seven_Hour_War"
],
[
"http://www.youtube.com/watch?v=OHxyZaZlaOs"
],
[
"http://members.shaw.ca/halflifestory/"
],
[
"http://half-life.wikia.com/wiki/Timeline_of_the_Half-Life_universe",
"http://members.shaw.ca/halflifestory/"
],
[
"http://www.youtube.com/watch?v=SCSKbAp-cQQ"
],
[],
[],
[],
[
"http://www.members.shaw.ca/halflifestory/"
],
[]
] |
|
6g83qb | how is it uk's exit polls were so accurate when exit polls in other countries, like usa, are often wildly off? | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/6g83qb/eli5_how_is_it_uks_exit_polls_were_so_accurate/ | {
"a_id": [
"dio6uc5",
"dio8003",
"dio8006"
],
"score": [
3,
2,
2
],
"text": [
"They didn't know it would be so close, but the exit polls are the only indicator they have available at that point, so they work with what they have. News reporting is not generally known for being overly cautious about the possibility of statistical errors.\n\nExit polls in the UK are about as accurate as in other countries. Sometimes they're close to the true outcome, sometimes they're relatively far off. They were quite close this election, but a single good showing doesn't mean they've somehow solved the problem; as the saying goes, even a stopped clock is right twice a day.",
"We have far fewer polling stations, making it much easier for us to obtain a truer picture of the actual results.\n\nThey break down the vote by age, occupation & vote to form a picture of the overall total in each constituency. By creating demographic groups formed from a combination of age & occupation, then comparing the distribution of votes from the sample size to the total population of that demographic that are registered & likely to vote, you can extrapolate the votes for each party in that constituency to form a good overall estimate of the result. On the contrary, American exit polls have a much smaller relative sample size and do not analyse the data as intelligently.\n\nProblems in the past, such as the unexpected conservative victory of 1992, was due to conservative voters being less likely to stop and participate in exit polls. There have since been adjustments to how we take exit polls - for example we now use a very quick and simple tablet response system with ~3 simple multiple choice questions. This essentially makes it quicker to just do the poll than saying \"No, thank you.\"\n\nFurther to the point I just made, I imagine the biggest reason for a shock result in the US would be partially due to certain demographics being less responsive to exit polls. The British tend to be much more willing to take part in exit polls across the board, making estimates much more accurate. As well as this, the US is a much bigger country with a much wider range of political nuances to account for.\n\n > \"The voter survey is based on questionnaires completed by 24,537 voters leaving 350 voting places throughout the United States on Election Day including 4,398 telephone interviews with early and absentee voters.\" - [NYTimes](_URL_2_)\n\n**The US 2016 General Election comprised of [130 million](_URL_0_) voters. That's a poll ratio of 0.02%. In comparison, the exit poll of 2015 in the UK interviewed 30,000 people, with a voting population of about 30 million, giving a poll ratio of about 0.1% - 5 times more than in the US. This combined with the other factors mentioned above results in a much more accurate picture of the election.**\n\n---\n\nEDIT: For OP if you're still interested and missed the conversation in the mod removal message:\n\n > Are US exit polls not accurate?\n\nYes, they aren't very accurate compared to UK polls.\n\n > \"Because only a small sample of voters fill out the questionnaires, and those choosing to do so are likely to be younger, the results may be skewed towards particular groups.\" - [Independent](_URL_1_).\n\n1. The way in which the US conducts election polls skews results. The UK conducts a much better servey evaluation across demographics and then uses voter population data to assign that total demographic a distribution of votes, rather than just adding up the exit poll numbers and getting a very rough estimate.\n\n2. They do not account for state bias very well, failing to properly address the fact that the vote is based on the electoral college, not a the percentage of votes obtained. (This is the same reason why the brexit exit poll was innaccurate - it was a measure of a total percentage of votes). In the UK, we predict which constituencies will win, and form a result from that, giving us an accurate view.\n\n3. The US exit polls are a much smaller sample size than the UK ones relative to the total population.",
"I heard something on NPR reflecting this statement. The \"expert\" said the exit poll question in the UK is \"How did you vote?\" In the US, the question is typically \"How do you intend to vote?\"\n\nI'll try to find a source to back it up, and not sure if this is a good explanation on its own. But it makes a certain kind of sense. \n\nEdit: poll, not polk."
]
} | [] | [] | [
[],
[
"http://www.telegraph.co.uk/news/2016/11/14/us-election-2016-voter-turnout-fell-to-58-per-cent-this-year-est/",
"http://www.independent.co.uk/news/world/americas/us-elections/what-is-an-exit-poll-final-result-us-election-2016-donald-trump-hillary-clinton-a7404396.html",
"https://www.nytimes.com/interactive/2016/11/08/us/politics/election-exit-polls.html"
],
[]
] |
||
3um68p | what would actually happen to a small child if they drank alcohol beverages often(one glass of wine each day, for example)? | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/3um68p/eli5_what_would_actually_happen_to_a_small_child/ | {
"a_id": [
"cxfy3lg"
],
"score": [
14
],
"text": [
"One glass might be a lot for a small child, depending on how small. But I grew up allowed to drink a small amount with dinner and usually did, and I'm fine. There's [much evidence](_URL_0_) that drinking in moderation with the family below the legal age leads to less alcohol abuse in teen years, college, adulthood. "
]
} | [] | [] | [
[
"http://www.amazon.com/Natural-History-Alcoholism-Patterns-Recovery/dp/0674603753"
]
] |
||
63q6ny | why and how does smoking cigarettes kill you? | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/63q6ny/eli5_why_and_how_does_smoking_cigarettes_kill_you/ | {
"a_id": [
"dfw517z",
"dfw5xq5"
],
"score": [
5,
2
],
"text": [
"Some people live longer (or shorter) lives due to their genetic makeup. But here's the thing...smoking has been shown overwhelmingly to decrease the years someone will live cancer-free across the spectrum of that genetic makeup. In other words, if you would have lived for 90 years before getting cancer without smoking, you'll get it at 65 with smoking (actual numbers are completely made up and are not necessarily statistically significant) while someone who would have gotten cancer at 25 because they smoked managed to avoid it until 40 without smoking.\n\nAnd that's just the cancer-related aspect - there are a whole host of other problems that smoking introduces that aren't directly cancer-related.",
"Like all chemicals that cause cancer, whether it gives *a particular person* cancer involves a lot of luck. Random chemical damage to DNA in a cell (a mutation, caused by the chemicals in the smoke) usually just damages or kills the cell. It's bad luck if the damage happens to turn one cell into a fast-multiplying, life-threatening cancer cell."
]
} | [] | [] | [
[],
[]
] |
||
xuywg | simple radiation. alpha, beta, gamma and x-ray. please eli5 | I have tried to search to avoid re-posting but can't find anything I understand.
I am a firefighter and trying to understand radiation a little more. We are taught how to deal with radiation but not the basics of what it is.
Can someone please explain:
What each of these are?
What would the sources most commonly be/look like? (i.e a big green stick like the simpsons!)
What are the common differences? (not scientific make up just how they act and what they do.)
And any information you think could help.
Thank you for any help you can offer. | explainlikeimfive | http://www.reddit.com/r/explainlikeimfive/comments/xuywg/simple_radiation_alpha_beta_gamma_and_xray_please/ | {
"a_id": [
"c5pta39",
"c5ptgum",
"c5pts75",
"c5pucox",
"c5puozh"
],
"score": [
3,
10,
5,
3,
3
],
"text": [
"alpha: just releases helium. it's not dangerous whatsoever.\n\nbeta: can be a little dangerous, its best to keep it in a container. \n\ngamma: extremely dangerous. causes cancer, and kills people.\n\na geiger counter is how it's found. there isn't really a unique color or anything on that nature. radiation is invisible to our eye.",
"To start off here, first you need to split these into two categories, the first of which is electromagnetic waves and particles. X-rays and gamma rays are electromagnetic waves, meaning that they are essentially forms of light, but with a frequency much higher than that of the light that we can see, so essentially they are waves of high energy, with gamma rays having higher frequencies and higher energies than x-rays. These are are called radiation sources since they are able to ionize other particles due to their high energy, which could end up damaging particles, such as DNA, which is why they are considered as dangerous. Gamma rays, since they have higher frequencies, have much greater ability to penetrate through materials than x-rays, this may seem clearer when you think of an x-ray of your arm, the x-rays are able to penetrate through the skin and flesh, but not through bones and metals, which is how you end up with an image, whereas gamma radiation can penetrate through almost 1 foot of lead, which is a really dense material.\n\nAlpha and beta radiation are different, since they deal with the radioactive decay of a nucleus. This process occurs when you have really heavy nuclei, which tend to become unstable so they reform themselves into lighter nuclei by releasing either an alpha or a beta particle. Alpha particles are when a heavy nucleus releases two protons and two neutrons, essentially the nucleus of a helium ion. This is positively charged and as a result to high exposure to alpha decay radiation damage could be caused. But due to the fact that this particle is relatively large, it has a short range, where it can only travel a few centimeters in the air, it is not that dangerous. Beta decay is when a neutron in the nucleus of an atom decays into one proton and electron, and this electron is released at high energy, giving it a medium range in terms of distance and a medium ionizing power, since it is charged, meaning that it can reach a distance of approximately 10m, and can cause damage at high exposure.\n\nAs for sources of these, x-rays, I believe are not known to spontaneously evolve, but rather they are a result of shooting an atom with electrons and forcing the electrons within the atom to reshuffle which leads to x-ray generation. As for alpha, beta and gamma radiation, they are a result of the radioactive decay of heavier elements, such a uranium, polonium, radium... etc, generally metals that have high atomic numbers in the periodic table. So essentially, these are elements, which I believe are subject to control laws, which means the average citizen will not have access to them. Also, radioactive materials have to be clearly identified as such and stored in containers that limit the effect of the radiation on the surrounding, depending on what type of radiation they emit. So, sorry no glowing sticks, that's essentially the exaggerated touch of Hollywood.\n\nAs for effects, being exposed to ionizing energy could cause cancer, and this is due to the fact to the ionizing of your DNA, which undergoes a mutation when ionized, and given enough mutations you could develop cancer. That is why the amont of each type of radiation that you can be exposed to is limited and exceeding the limit can cause irreversible damage. \n\nI hope I didn't overcomplicate things for you, since this is my first ELI5.\n\nedit - fixed a couple of spelling mistakes",
"Radiation is one of the products of Radioactive Decay, a process atoms go through when they are in an unstable state. During the process, the parent atom kicks off a subset of atoms *or* energy to get to a more stable state. The specific 'type' of radiation depends on the start and end atoms, and therefor what has been ejected.\n\n* Alpha radiation is a Helium-4 atom, two protons and two neutrons. It tends to be less dangerous, normal clothing stops it well enough. In relation to the others, this is a small foam ball. Unless it hits you in an existing wound, you don't have anything to worry about.\n\n* Beta radiation is an electron or positron (not a proton). You need special protection from this, but nothing extreme - your firesuit should provide enough protection, I would guess. In relation to the others, this is a paint ball. It's gonna sting if you don't suit up, but if you do you're more or less ok.\n\n* Gamma radiation tends to be a by-product of the above two. The process leaves a lot of excess energy, which is given out as Gamma radiation. This is the dangerous one - think heavy lead shielding for this one. Obviously, not practical for moving around. This is the BB gun. \n\n* X-ray is pretty much Gamma radiation from a different part of the atom. Same problems.\n\nThere's always some radioactive particles whizzing around, so called 'background radiation'. As for recognizing significant sources, there are no sure signs beyond labeling. Most dangerous sources will be clearly marked as such with the usual hazard symbol. Any other sources will, in all likelihood, be giving off too little radiation to be a health risk.\n\nIf you're really curious, take apart a smoke detector. There's a little chip containing a minuscule amount of americium-241 in there that makes it work. It's also one of the most radioactive things most people will have in their house, along with the microwave, and obviously not very dangerous.",
"Alpha particles come from a type of radioactive decay where the atom emits Helium atoms. These are basically just regular air molecules, they are odorless and colourless, and will bounce off a sheet of paper. One neat thing about them is it actually causes the original atom to transform into a different element. They are mostly harmless.\n\nBeta particles are a result of a different type of radioactive decay where the atom emits electrons. These are much smaller and lighter than alpha particles, travel much faster, and can penetrate a thin sheet of metal. These are dangerous and can in some cases cause cell mutations which may lead to cancer but will usually just give you a radiation burn. Ironically they can also be used in radiation therapy to kill cancer cells. \n\nBoth beta and alpha particles come from unstable elements decaying. These sources basically just look like regular lumps of rock.\n\nGamma rays are not particles, but very high energy radiation. They can come from radioactive decay like the first two but also exist in space and can be released by certain types of galaxies. They will pass through pretty much anything except for lead. These are extremely dangerous and are what can give you serious and immediate radiation sickness if you get too exposed to them.\n\nX-rays are similar to gamma rays but aren't quite as high energy and unlike the other three, these do NOT come from radioactive decay. There are some natural sources of X-rays, but most of the time we can actually create X-rays by running electricity through a special tube. The atoms in the tube absorb the electricity and release the energy in the form of X-rays. They are invisible and will also pass through most materials. These are dangerous but less dangerous than gamma rays and have many medical applications.\n\nSadly, real radioactive decay doesn't usually glow pretty colours like on TV. BUT, and this is taking this a bit further than you asked so forgive me, if you ever get a chance to visit a nuclear reactor you will notice that it *does* have a glow. This isn't actually the radiation itself, but caused by the radiation travelling *faster than light* in the water. It turns out that light is only the fastest thing in the universe when it's in a vacuum... pass it through a substance and all bets are off. You know how jets create a sonic boom when they break the speed of sound? That is exactly what is happening in the reactor - the tiny, super-fast, beta particles create a billion tiny \"light booms\".",
"Like you're five version:\n\nEverything is made up of tiny particles called atoms. These 'atoms' are composed of even smaller particles, and it is this unique composition of the smaller particles that determines the atom's properties, e.g. is it shiny, does it fizz in water, etc.\n\nThere are large atoms that contain many of these 'smaller' particles, and small atoms that contain less. \n\nAtoms can breakdown, and the smaller particles inside of them are now free. This is one form of radiation, and for the most part harmless.\n\nHowever, when these atoms breakdown, they also release energy, usually in the form of a light you can't see. This is the dangerous one, because this dangerous light can come into contact with other particles and cause them to breakdown starting a chain reaction. You body is a complex combination of atoms, whose unique properties work together to keep you alive. Once atoms in body start changing due to coming into contact with this dangerous light, the particles in your body may become toxic, and you get things like cancer.\n\nThe problem with trying to identify sources by sight is that the really dangerous light cannot be seen with the naked eye. Common sources of radiation, such as plutonium and uranium, look like generic metals. The only real way to identify them is with special radiation detectors. \n\nA common one is called a 'Geiger counter' which emits beeps when the gas inside it is broken down by radiation. More radiation = more beeps.\n\nIn facilities such as nuclear facilities, or those that conduct other high energy physics experiments such as CERN, scientists are required to wear special detectors that look like thick ID badges, that keep track of their exposure, because radiation damage is cumulative. At CERN, the radiation comes from the particle accelerators and associated machinery, instead of just lumps of grey metal."
]
} | [] | [] | [
[],
[],
[],
[],
[]
] |
|
2j5h0d | why don't my balls get twisted up in my scrotum? | I feel like, even though they're attached to separate veins, they could still wrap around each other and cut off circulation or something. | explainlikeimfive | http://www.reddit.com/r/explainlikeimfive/comments/2j5h0d/eli5_why_dont_my_balls_get_twisted_up_in_my/ | {
"a_id": [
"cl8jq3g",
"cl8jqzv",
"cl8k7q1"
],
"score": [
3,
3,
7
],
"text": [
"They actually can... and its REALLY bad if they do. You can lose a testicle if they get tangled up on each other. \n\nDoctors can correct it but not if the damage is too severe.",
"That does happen. Google \"Testicular torsion\". I think that's what it's called.",
"The testicles aren't just hanging there attached to veins. They're attached to fairly solid \"stalks\" that are bundles of blood vessels, nerves, and muscles. Each testicle is also attached to the scrotum itself. That combination means that they're pretty firmly held in place.\n\nThe danger isn't of them wrapping around each *other*, but of a single testicle twisting it's \"stalk\", cutting off bloodflow. This is called [testicular torsion](_URL_0_), and is usually caused by a genetic deformity that causes the testicle to not be firmly attached to the scrotum."
]
} | [] | [] | [
[],
[],
[
"http://en.wikipedia.org/wiki/Testicular_torsion"
]
] |
|
13pc8b | musical keys - wtf? why, for example, should 'lick my love pump' sound 'sad' just because it's written in d minor? | I have a music theory test on Wednesday next week and this is just one of the many things which has been bothering me.
I don't grasp how keys affect the sound and emotional tone of the music - who does, and how can you explain it simply?
Thanks in advance! | explainlikeimfive | http://www.reddit.com/r/explainlikeimfive/comments/13pc8b/musical_keys_wtf_why_for_example_should_lick_my/ | {
"a_id": [
"c75z0wr"
],
"score": [
7
],
"text": [
"A great question! And one that we can't answer definitively. There are some theories, the main one being that the same theory behind minor keys is used in our voices when we use sad speech. The order of and \"distance\" between the notes in our speech patterns when giving bad news or even taunting others is the same as the order of and distance between the notes in minor keys. Specifically, something called the minor third is being emphasized in both. Additionally, major keys are similar to excited speech.\n\nNow comes the question of whether minor music led to our sad voices or the other way around. This is debated, too. The general consensus tends to be that our speech patterns came first and has led to our feeling minor keys as \"sad\". It's also important to understand that not all songs written in a minor key sound sad. This can be due to a variety of reasons an theory that's not necessary to get into here, but is an interesting subject to do some more research on if you want to.\n\nFor some more info/better explanations check out these links:\n\n[Here](_URL_2_)\n\n[Here](_URL_0_)\nand \n\n[Here](_URL_1_)\n\n"
]
} | [] | [] | [
[
"http://www.newscientist.com/article/dn18367-songs-in-the-key-of-life-what-makes-music-emotional.html",
"http://www.theatlantic.com/entertainment/archive/2010/12/what-makes-a-song-sad/67709/",
"http://www.nature.com/news/2010/100108/full/news.2010.3.html"
]
] |
|
3ytumy | how do psychics "read" people? | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/3ytumy/eli5_how_do_psychics_read_people/ | {
"a_id": [
"cygjmg9",
"cygjn0j",
"cygkg9t",
"cygnka0",
"cygqvhs"
],
"score": [
5,
40,
4,
2,
7
],
"text": [
"It's a matter of making broad statements which sound really specific, but actually apply to lots of people.\nSomething like \"I feel like your dad always forgot his keys\" probably applies to most people, but to someone who really wants that to be true, they will easily latch on to these details.\n\n",
"it's basically just bullshit, called \"cold reading\". the premise is, you make your statement so vague, that they apply to nearly every person. if you use a medium, like tarot cards, the cards only act as a medium for the bullshit, like if you pick a lover card, they just start saying random things about your love life, like \"maybe you're still in love with someone that got away\" or \"you're having relationships troubles current\" or \"you're not sure if you should take a big step forward in your current relationship\" etc, and they judge your reactions to see how close to the mark they are. they just look at you and basically just guess until they hit something true. the remarkable thing is, if someone is just purely guessing at you but you manage to get 1 thing right out of 100, they'll focus on that one thing and be amazed.\n\n_URL_0_",
"Like u/jnxjnx said, a lot of it comes from watching one's reaction to things said by the \"psychic\". A lot of times they will establish a baseline on the subject to see how they react and posture themselves during normal conversation, so that later when they make guesses about the persons life they will notice a non-verbal reaction. For example, if someone normally sits back in their chair with their arms crossed (a closed position) but then when the psychic brings up a certain topic the subject leans foward and uncrosses their arms (an open position), the psychic knows they have hit on something the person wants to talk about. There are all kinds of non-verbal cues that you see (and interpret) all day long without knowing it. It's just a matter recognizing and using them to your advantage. If you've never watched it, I would suggest the TV series Lie to Me. It is fiction but is built around these concepts. \nSource: I'm a police officer with advanced interrogation and interview techniques. ",
"They use a technique called cold reading that is also used by police interrogators and salespeople. It involves starting with generalised statements that could apply to anyone and observing how the interviewee reacts, then building upon any information they can deduce to elicit more concrete details from the interviewee. ",
"South Park did a great job of explaining this. I know we're supposed to explain ourselves, but [I think they do a great job.](_URL_0_)"
]
} | [] | [] | [
[],
[
"https://en.wikipedia.org/wiki/Cold_reading"
],
[],
[],
[
"http://southpark.cc.com/clips/153776/the-other-side"
]
] |
||
79nl7a | when people say that the pressure deep underwater would crush a human, how would that go down exactly? | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/79nl7a/eli5_when_people_say_that_the_pressure_deep/ | {
"a_id": [
"dp3bqqm"
],
"score": [
14
],
"text": [
"Archimedes principle: pressure is evenly distributed in a fluid.\n\nSo what hat means is tiny ball scenario, you would be crushed from all sides. That being said, I don’t think the pressure is high enough to literally crush you into a tiny ball, it would just be too high for your lungs to open and breath. Either the nitrogen would get pushed out of your blood (and you would get a bubble in your vein and die) or you would suffocate.\n\nBut the pressure would come from all around you."
]
} | [] | [] | [
[]
] |
||
23ejs8 | if muslims do not believe jesus died on the cross, what exactly happened to the man? | explainlikeimfive | http://www.reddit.com/r/explainlikeimfive/comments/23ejs8/eli5_if_muslims_do_not_believe_jesus_died_on_the/ | {
"a_id": [
"cgw7m9q",
"cgw87uo",
"cgw8dxw"
],
"score": [
2,
2,
2
],
"text": [
"I'm not sure what their stance is on the crucifixion. I'm an atheist and while I dunno that it's 100% proven, it seems reasonable to think that Jesus was indeed crucified - we know the man existed, that there was a semi-uprising in Judea around that time, and crucifixion was a common execution method. Not believing he was divine doesn't mean he wasn't crucified.",
"My Arabic teacher explained it to me that some Arabs believe that Jesus was a dude and that Christ was a spirit that inhabited him and right before Jesus died Christ left him and went to heaven. And that is why he shouted \"why have you forsaken me?\" Because he didn't expect Christ to leave him. So Jesus did die on the cross, but the thing/spirit that we think of as \"JESUS\" didn't.\n\nOr something to that effect. But that is definitely not my expertise.",
"Because your post isn't asking a simplified conceptual explanation, but rather for an answer, it has been removed. \n\nYou should try /r/answers, /r/askreddit or even one of the more specialized answers subreddits like /r/askhistorians, /r/askscience or others too numerous and varied to mention. \n\nRest assured this doesn't make your question *bad*, it just makes it more appropriate for another subreddit. Good luck! "
]
} | [] | [] | [
[],
[],
[]
] |
||
4xxs8x | with fight or flight, is there an effective way to overcome the freeze response? | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/4xxs8x/eli5_with_fight_or_flight_is_there_an_effective/ | {
"a_id": [
"d6jd58l",
"d6jfxzk"
],
"score": [
7,
4
],
"text": [
"Training. Specifically, what is known as \"stress inoculation.\" \n\nThis is why new recruits in the military have to complete tasks while being yelled at and generally messed with by their instructors- a crude imitation of the stress of combat. It's why high quality police training involves responding to crises amidst all sorts of artificial stressors like simulated ammunition and panicked victims. It's why professional boxers get hit again and again and again long before stepping into the ring. \n\nIf you are routinely exposed to a certain kind of stress, you can become desensitized to it. Mental armor, so to speak. You can be trained to *act* when faced with stress rather than freezing up. ",
"Unless you've prepared for a \"fight or flight\" situation, I don't know if there's a way to prevent a freeze response.\n\nSpeaking from personal experience, I once had a freeze response when I was walking to my car late one night and another car sped around the corner and started to come right at me like it was about to run me over. I froze for a moment before running to get out of the way. I think it was because my mind hadn't prepared itself for a situation like that. I was totally at ease, then, suddenly, I was in danger. I almost couldn't believe it was happening. If I had put myself more in the mindset that something bad could happen as I walked to my car, then I may have reacted more quickly.\n\nNeurological pathways in your brain are strengthened by repetition so preparing yourself through simulation (or even visualization) can strengthen pathways that lead to your body's fight or flight response. I think that the freeze response is caused by your brain not being prepared enough to react. Even if you haven't mentally prepared for an exact scenario, the strengthened pathways can still adapt quickly if a situation is similar to one you're familiar with. For instance, if your mental/physical response has prepared you for responding to people next to you getting in a fight on the bus, you might also be prepared for someone trying to snatch your necklace on the street. They're different situations, but they may use the same neurological pathways to get to your ultimate response.\n\nIf you've rarely had to plead your case in an argument/debate then you probably won't win many of them. Neurological pathways can be strengthened through repetition when it comes to your memory recall in times of stress which can help when in a discussion or when you're in a rap battle like Eminem in the movie 8 Mile. He froze because he wasn't prepared for the stress. By the film's climax, Eminem's character was prepared but the guy he rap battled at the end froze because he wasn't prepared for the stress of being so embarrassed like that. He'd only experienced what it was like to go into a situation knowing what he was going to say—not having to improvise based on new stimulus."
]
} | [] | [] | [
[],
[]
] |
||
nfdzd | a maths matrix | explainlikeimfive | http://www.reddit.com/r/explainlikeimfive/comments/nfdzd/eli5_a_maths_matrix/ | {
"a_id": [
"c38n7xc",
"c38nv6n",
"c38qw06",
"c38n7xc",
"c38nv6n",
"c38qw06"
],
"score": [
9,
4,
3,
9,
4,
3
],
"text": [
"A matrix is just a rectangular grid of numbers.\n\nThey're useful because matrices can be used to represent a certain class of functions known as \"linear transformations\". When you do this, certain properties of the function can be determined from properties of the matrix.",
"So, matrices are useful for a lot of really weird abstract functions, but the most useful application is in 3D math.\n\nLet's say that we're meeting in real life and talking to each other. I'm standing in one point and facing one direction, and I say \"Check out this cool thing three feet to my left!\". You're standing in another point and facing another direction, so my \"three feet to my left\" could be your \"five feet to my right\" or \"two feet above me and one foot ahead\" or whatever, depending on where we stand in relation to each other.\n\nNow, intuitively, you might suspect that there's some set of rules you can apply to go from my \"three feet to Extirpare's left\" to your \"five feet to the right of zingzong70\" for any possible item in any possible location. For instance: if you're standing two feet to my right and looking south while I'm looking north (so \"three feet to my left\" becomes \"five feet to your right\"), you could just say \"wherever you tell me something is in relation to your perspective, I should add two feet and flip directions\". THAT is what a matrix represents.\n\nAnd if your five-year-old understands that, I will be impressed.",
"So, let's say that we want to go somewhere in the forest, but you only know the directions by walking a certain distance from a variety of interesting objects (like a really awesome shaped very large rock), but you don't know how to just go straight there. Well, in maths, each of those steps can be transformed in to what is called a \"vector\". Now, we represent these vectors in terms of triangles.\n\nHowever, when making these triangles, we gotta be careful. See, first, we need to have some agreement on which directions are which, since if we're facing each other, left and right are different ([extirpare's explanation might help](_URL_0_)), since my right is your left, and so we all agree that the way our compasses point, which is generally always constant, is always North, and the direction of the sky, which is generally always constant, is up. Now, that we have that, we can tell you to go 1000 feet north and 200 feet up to get from the base of the ree to the top of the rock. Now, if you draw that out you could get a kinda long trip, but if you take a line that is 1000 feet \"north\" and then attach a line that is 200 feet up, you can just take a line and draw straight from the point where you start at the tree and attach it to the point at the top of rock. We call this new line the \"vector\" and we write it as (1000ft north, 200ft up, 0ft West ), or simply (1000, 200, 0).\n\nNow, what matrices special, is that all they really are is a vector made of vectors. What makes that really cool though, is that we can then find ways to easily do the maths to ADD vectors by using MATRIX MULTIPLICATION. You see, if we wrote our vector like it was up-down instead of left-right (a COLUMN vector), and then we wrote a bunch of other vectors next to it, we would get a Matrix. \n\nNow, you may wonder why you would want to do this, and so, now, imagine that you're trying to be the best waiter ever, but you just got a REALLY complicated order. If your restaurant had, say, only 5 items and you had 20 people who ordered in one big group, you could represent each person's order as a vector with 5 things in it, how many of each food they ordered, and then take each of these 20 vectors and, instead of standing them up next to each other as columns, you could lay them down on top of each other (as ROW vectors). In this matrix, each row would represent one person and each column as one food item. If you then created a new vector, which had the price of each food item, you could do something REALLY cool, matrix multiplication. What is matrix multiplication? Well, you take each row of one matrix and multiply it with a column of another matrix (you gotta have the same number of entries in each!), which you can do by multiplying the first entry in the row by the first entry in the column, then multiply the second entry in the row by the second entry in the column, and then you keep multiplying the n'th entry in the row by the n'th entry in the column AND THEN, this is where things get crazy, you add up all those new numbers you got by multiplying all those things! How could this complicated method make things EASIER? \n\nWell, mr./ms. impatient waiter/waitress, a vector is really just a matrix with one vector in it and so, since each row in your matrix made up of food orders has 5 entries and the row in your price matrix is made up of 5 entries, you can multiply them! Not only that, but when you multiply them, you're getting something useful, a new vector/matrix made up of how much each person needs to pay. How? Well, the first item in each row is how many of that item, say a hamburger, that that person ordered, and the first item in the column is how much a hamburger costs. So, if you then multiply the number of hamburgers a person bought by how much hamburgers cost, and then do that with pizzas, cokes, french fries, and grilled cheese sandwiches, and then add ALL of that up, you'll get how much that person needs to pay on their check! Since you're storing all your customers in a neat little matrix, when you multiply by another matrix (the prices!) you get a new matrix, with each n'th row and m'th column corresponding to multiplying the n'th row of the first matrix by the m'th column of the second matrix. What that means is, you get a new matrix where the first entry is the amount the first customer owes you, the second entry is the amount the second customer owes you, etc. and, since matrices allow you to forget about hamburgers, pizzas, and cokes and just add and multiply numbers, you (or a computer!) can do them really fast and end up with an answer in an easy to understand format. \n\nMuch more surprising and useful, if you have the number of items each person ordered and how much each person paid, what's called a series of equations, you can turn the orders into a matrix and how much the people paid into another matrix, and, this is SOOOOOO cool, solve for how much each item cost. Visually, you can probably solve an equation of the form\n 5x = 3.\nHowever, if you replace that 5 with the matrix of the orders and the 3 with the matrix of how much each person paid, you could STILL solve for x, assuming, of course, that such an answer existed. Not only that, but if there are multiple answers or no answers, say because you wrote something down wrong, you can figure that out exactly, and say with 100% perfect confidence that there is one solution, are many solutions, or ain't any solutions. And, going back to what I said earlier about vectors, let's say, you have a bunch of vectors and you want to add up multiples of them up easily, (I'm sorry, I'm tired and can't think of an example), well, if you make them the columns in a matrix and then put how much you want each vector to be multiplied by in the columns of another matrix and multiplied them together, the new vector you get would be equivalent to multiplying each original vector by the multiple you choose and adding them up manually, but matrices are nice and compact and pretty for that type of stuff.\n\nEDIT: Okay, so if the columns were say the \"base vectors\" for North, up, and West, that is the vectors that go 1 ft (or meter) in the North, up, and West directions, if you wanted to tell someone to go 20 feet North, 2 feet up, and 500 feet West, you would make a matrix of those \"base vectors\" and multiply it by a vector (20, 2, 500) to get the net direction you need to go. WHat's interesting though, is, if you wrote your directions using North-West, South-West, and down, you could actually make new \"Base vectors\" representing North-west, south-west, and down in your North-Up-West direction system, and then if someone wrote directions using North-west, south-west, and down, you could find how to get their using North-Up-West by taking the south-west , north-west, and down vectors written in your system (they'll look pretty funny, with south-west being (-1/sqrt(2), 0, 1/sqrt(2)) for example) and then multiply them by how far you need to go in those directions, and suddenly you'll have how far you need to go North, Up, and West! I'm a math major and I just got done with a thorough second semester of Linear Algebra (which includes the study of vectors and matrices) and so I tried to include some actual uses and the theoretical base of why it all works, but I may have been to in-depth or vague in parts, so if you want clarification on anything, please ask. I still think some of the stuff you can do with matrices and vectors is.... kinda magical, honestly.\n",
"A matrix is just a rectangular grid of numbers.\n\nThey're useful because matrices can be used to represent a certain class of functions known as \"linear transformations\". When you do this, certain properties of the function can be determined from properties of the matrix.",
"So, matrices are useful for a lot of really weird abstract functions, but the most useful application is in 3D math.\n\nLet's say that we're meeting in real life and talking to each other. I'm standing in one point and facing one direction, and I say \"Check out this cool thing three feet to my left!\". You're standing in another point and facing another direction, so my \"three feet to my left\" could be your \"five feet to my right\" or \"two feet above me and one foot ahead\" or whatever, depending on where we stand in relation to each other.\n\nNow, intuitively, you might suspect that there's some set of rules you can apply to go from my \"three feet to Extirpare's left\" to your \"five feet to the right of zingzong70\" for any possible item in any possible location. For instance: if you're standing two feet to my right and looking south while I'm looking north (so \"three feet to my left\" becomes \"five feet to your right\"), you could just say \"wherever you tell me something is in relation to your perspective, I should add two feet and flip directions\". THAT is what a matrix represents.\n\nAnd if your five-year-old understands that, I will be impressed.",
"So, let's say that we want to go somewhere in the forest, but you only know the directions by walking a certain distance from a variety of interesting objects (like a really awesome shaped very large rock), but you don't know how to just go straight there. Well, in maths, each of those steps can be transformed in to what is called a \"vector\". Now, we represent these vectors in terms of triangles.\n\nHowever, when making these triangles, we gotta be careful. See, first, we need to have some agreement on which directions are which, since if we're facing each other, left and right are different ([extirpare's explanation might help](_URL_0_)), since my right is your left, and so we all agree that the way our compasses point, which is generally always constant, is always North, and the direction of the sky, which is generally always constant, is up. Now, that we have that, we can tell you to go 1000 feet north and 200 feet up to get from the base of the ree to the top of the rock. Now, if you draw that out you could get a kinda long trip, but if you take a line that is 1000 feet \"north\" and then attach a line that is 200 feet up, you can just take a line and draw straight from the point where you start at the tree and attach it to the point at the top of rock. We call this new line the \"vector\" and we write it as (1000ft north, 200ft up, 0ft West ), or simply (1000, 200, 0).\n\nNow, what matrices special, is that all they really are is a vector made of vectors. What makes that really cool though, is that we can then find ways to easily do the maths to ADD vectors by using MATRIX MULTIPLICATION. You see, if we wrote our vector like it was up-down instead of left-right (a COLUMN vector), and then we wrote a bunch of other vectors next to it, we would get a Matrix. \n\nNow, you may wonder why you would want to do this, and so, now, imagine that you're trying to be the best waiter ever, but you just got a REALLY complicated order. If your restaurant had, say, only 5 items and you had 20 people who ordered in one big group, you could represent each person's order as a vector with 5 things in it, how many of each food they ordered, and then take each of these 20 vectors and, instead of standing them up next to each other as columns, you could lay them down on top of each other (as ROW vectors). In this matrix, each row would represent one person and each column as one food item. If you then created a new vector, which had the price of each food item, you could do something REALLY cool, matrix multiplication. What is matrix multiplication? Well, you take each row of one matrix and multiply it with a column of another matrix (you gotta have the same number of entries in each!), which you can do by multiplying the first entry in the row by the first entry in the column, then multiply the second entry in the row by the second entry in the column, and then you keep multiplying the n'th entry in the row by the n'th entry in the column AND THEN, this is where things get crazy, you add up all those new numbers you got by multiplying all those things! How could this complicated method make things EASIER? \n\nWell, mr./ms. impatient waiter/waitress, a vector is really just a matrix with one vector in it and so, since each row in your matrix made up of food orders has 5 entries and the row in your price matrix is made up of 5 entries, you can multiply them! Not only that, but when you multiply them, you're getting something useful, a new vector/matrix made up of how much each person needs to pay. How? Well, the first item in each row is how many of that item, say a hamburger, that that person ordered, and the first item in the column is how much a hamburger costs. So, if you then multiply the number of hamburgers a person bought by how much hamburgers cost, and then do that with pizzas, cokes, french fries, and grilled cheese sandwiches, and then add ALL of that up, you'll get how much that person needs to pay on their check! Since you're storing all your customers in a neat little matrix, when you multiply by another matrix (the prices!) you get a new matrix, with each n'th row and m'th column corresponding to multiplying the n'th row of the first matrix by the m'th column of the second matrix. What that means is, you get a new matrix where the first entry is the amount the first customer owes you, the second entry is the amount the second customer owes you, etc. and, since matrices allow you to forget about hamburgers, pizzas, and cokes and just add and multiply numbers, you (or a computer!) can do them really fast and end up with an answer in an easy to understand format. \n\nMuch more surprising and useful, if you have the number of items each person ordered and how much each person paid, what's called a series of equations, you can turn the orders into a matrix and how much the people paid into another matrix, and, this is SOOOOOO cool, solve for how much each item cost. Visually, you can probably solve an equation of the form\n 5x = 3.\nHowever, if you replace that 5 with the matrix of the orders and the 3 with the matrix of how much each person paid, you could STILL solve for x, assuming, of course, that such an answer existed. Not only that, but if there are multiple answers or no answers, say because you wrote something down wrong, you can figure that out exactly, and say with 100% perfect confidence that there is one solution, are many solutions, or ain't any solutions. And, going back to what I said earlier about vectors, let's say, you have a bunch of vectors and you want to add up multiples of them up easily, (I'm sorry, I'm tired and can't think of an example), well, if you make them the columns in a matrix and then put how much you want each vector to be multiplied by in the columns of another matrix and multiplied them together, the new vector you get would be equivalent to multiplying each original vector by the multiple you choose and adding them up manually, but matrices are nice and compact and pretty for that type of stuff.\n\nEDIT: Okay, so if the columns were say the \"base vectors\" for North, up, and West, that is the vectors that go 1 ft (or meter) in the North, up, and West directions, if you wanted to tell someone to go 20 feet North, 2 feet up, and 500 feet West, you would make a matrix of those \"base vectors\" and multiply it by a vector (20, 2, 500) to get the net direction you need to go. WHat's interesting though, is, if you wrote your directions using North-West, South-West, and down, you could actually make new \"Base vectors\" representing North-west, south-west, and down in your North-Up-West direction system, and then if someone wrote directions using North-west, south-west, and down, you could find how to get their using North-Up-West by taking the south-west , north-west, and down vectors written in your system (they'll look pretty funny, with south-west being (-1/sqrt(2), 0, 1/sqrt(2)) for example) and then multiply them by how far you need to go in those directions, and suddenly you'll have how far you need to go North, Up, and West! I'm a math major and I just got done with a thorough second semester of Linear Algebra (which includes the study of vectors and matrices) and so I tried to include some actual uses and the theoretical base of why it all works, but I may have been to in-depth or vague in parts, so if you want clarification on anything, please ask. I still think some of the stuff you can do with matrices and vectors is.... kinda magical, honestly.\n"
]
} | [] | [] | [
[],
[],
[
"http://www.reddit.com/r/explainlikeimfive/comments/nfdzd/eli5_a_maths_matrix/c38nv6n"
],
[],
[],
[
"http://www.reddit.com/r/explainlikeimfive/comments/nfdzd/eli5_a_maths_matrix/c38nv6n"
]
] |
||
1nugts | why do we care so much about finding water on other planets, when other forms of life could have evolved to not need water? | explainlikeimfive | http://www.reddit.com/r/explainlikeimfive/comments/1nugts/eli5_why_do_we_care_so_much_about_finding_water/ | {
"a_id": [
"ccm4ped",
"ccm4xww",
"ccm4ywx",
"ccm5ap5",
"ccm6mys",
"ccm6p1y",
"ccm6rtp",
"ccm6xkt",
"ccm7awt",
"ccm7bhj",
"ccm7xzl",
"ccm7ygf",
"ccm88mr",
"ccm898q",
"ccm8fgd",
"ccm8iz0",
"ccm8o5i",
"ccm8r56",
"ccm93kz",
"ccm94eb",
"ccm94hq",
"ccm98b9",
"ccm9bfq",
"ccm9iqn",
"ccm9vub",
"ccm9xqr",
"ccma3iu",
"ccmb340",
"ccmbig9",
"ccmbx84",
"ccmc6ng",
"ccmc6sr",
"ccmcav9",
"ccmcejm",
"ccmcq3a",
"ccmcqef",
"ccmcufk",
"ccmdrad",
"ccme8uc",
"ccmejju",
"ccmfqz3",
"ccmgeys",
"ccmgj3h",
"ccmgmlx",
"ccmj22s",
"ccmjhwh",
"ccmkufr",
"ccmlakd",
"ccmlf1f",
"ccmmk4k",
"ccmn7ox",
"ccmoanr",
"ccmov14",
"ccmpozp",
"ccn0ptz"
],
"score": [
56,
1943,
8,
12,
700,
2,
40,
4,
3,
6,
63,
255,
3,
20,
5,
2,
7,
5,
5,
3,
3,
2,
2,
2,
2,
5,
4,
11,
6,
5,
2,
3,
2,
2,
2,
2,
2,
4,
2,
2,
6,
6,
6,
4,
2,
2,
2,
2,
2,
3,
2,
2,
2,
3,
2
],
"text": [
"Hydrogen and oxygen are quite common elements in the universe. Water should therefore be quite common as well. In fact, vast clouds of water have been discovered in deep space.\n\nFor life to start it'd have to start in a liquid, or possibly a very thick gas, because chemicals in rocks aren't going to mix together.\n\nWater would be one of the more common forms of liquid in the universe and so it's a good start. We know of life that needs water you see.",
"Life could exist out there that doesn't need water. However, most of the life we know of does. We're already looking for a needle in a haystack, if we expand the search to life that doesn't need water then we don't even know what the needle looks like anymore. \n\nEdit; apparently some stuff doesn't use water according to /u/chemosynth",
"Scientists are very aware that life elsewhere might be very different from life here on Earth. However, the problem is how we would ever be able to find that life. Extraterrestrial \"life\" could be extremely long-lived rock beings or other crazy things that we would have no ability to interact with or even recognize as being alive. So in order to narrow our search to something somewhat possible, we look for one thing that all life as we know it requires--water--in the hopes that, if we find life elsewhere, it will be similar enough to life on Earth that we can have a decent chance of communicating with them and understanding them.\n\n Also, knowing which other planets have water and are potentially habitable will be very useful if and when humanity starts colonizing beyond Earth",
"Most simple explanation I can think of is that we **care** about finding water on other planets because **we need** water. So finding it, oxygen, and whatever else humans need will get us closer to possibly living on other planets.",
"Imagine your mom gives you candy. The last thing you did before you got the candy was clap your hands.\n\nNow maybe you dont NEED to clap your hands to get candy, but last time you did clap your hands you got candy.\n\nSo when you want candy again you will clap your hands.\n\n\nWe have ONE data point for life. Earth. So when looking for life we look for things similar to Earth. Doesn't mean life can't be on non-Earth like things, but we know that life is on Earth so we look for Earth-like things.",
"All life we know of is dependant on water so it makes sense to look for water, second because we depend on water finding water on other celestial bodies it very important to not only space travel...but having it there upon our arrival is very necessary ",
"Life requires complex chemistry both to exist, and be created in the first place. Chemistry only happens if chemicals are able to interact. A great way for that to happen is for the chemicals to be dissolved in something else.\nWater is common, and lots of chemicals are soluble in it. It's exceptionally good at dissolving things. So if life exists elsewhere, there's a good chance it developed in water, and its chemistry would continue to require water.\nSo water is a good place to start looking.",
"It's not just water. We have also noticed that we live on a planet orbiting a star, so we are mostly just looking for planets orbiting stars that have water.",
"One of the main important parts of finding water within our solar system, specifically looking at the inner solar system (i.e. Mars and the moon) is the search to find a place that may be habitable by humans in the future.",
"Well as others have said, we have no other reference point. Even if we did find life that evolved w/o water, we may not even be able to recognize it.\n\nHowever, the biggest reason is because of probability. liquid water allows for a lot of mobility of things, which greatly helps the natural selection process as well as giving living things the little things they need. It's much more likely for something to evolve in a slushy puddle filled with different things all moving around, rather than in the dry barren immobile sand. ",
"This answer on a related question four months ago explains this very well:\n\n\"While life definitely doesn't HAVE to be water-dependent, water is so good at sustaining life that it's a likely candidate. Consider that water:\n\n1) Can help two major types of chemical reaction to occur. (For the science-lovers: It is amphoteric and protic and thus can act as a base or an acid to catalyze many types of reactions)\n\n2) It can hold of a lot of different things in it, such as salt and sugar, essential to life as we know it, as well as waste products of cells. (It is quite polar [i.e. has slightly positive and negatively charged regions] and thus can dissolve nearly any molecule with a polar group on it.)\n\n3) It is a liquid over a wide range of temperatures, and we would expect that you'd need life to start in a liquid because you need nutrients to be able to flow easily toward an organism and waste to be able to flow away. (A range of 100 degrees Celsius; ammonia is quite similar to water but a liquid only in a range of ~45 degrees Celisus.)\n\n4) It floats as a solid. (If temperatures DID dip below the freezing point, the solid phase would float and life would not be crushed or frozen inside)\n\n5) Water is very stable and hard to break apart. (Otherwise, it would rapidly disappear)\n\n6) Water is very common in the universe compared to other molecules.\n\n\n...All of which makes it a very good place to start looking for life.\n\nEDIT: I'm getting a few comments that a five year old would not understand my response. The sidebar says \"Please do not criticize a post or response because it is not something a literal five-year-old would know or ask\" and to make your answer \"layman-friendly.\" I tried to make my response basic but put some of the science in parentheses for people more science-minded who wanted a fuller answer, but I apologize if my reply was at all overly complex.\n\nEDIT 2: Some people (thanks Charlestonian, tylerthehun) are bringing up a great point that I missed:\n\n7) It takes a LOT of heat to get water to change temperature. This means that it can \"hold itself\" at a temperature that is hospitable to life and resist change much better than other liquids. This is why you can put a pot of water on a burning hot stove and it still takes so long to boil!\n\n(This is known as \"heat capacity\" and is measured as how much energy it takes to raise one gram of a substance's temperature by 1 degree Kelvin/Celsius. Water's heat capacity is about 4 J/gK [i.e. it takes 4 JOULES of energy to raise 1 g of water by 1 degree Kelvin/Celsius] whereas other liquids are generally lower. Acetic acid is about 2 J/gK, ethanol is about 2 J/gk. Here's a table of more:)\n\n_URL_1_\n\nEDIT 3: Thank you for the /r/bestof submission!\"\n\n_URL_0_\n\n",
"It's an interesting question, whether or not water is a requirement for life. It's generally accepted that, for life to occur, you need a solvent to aid in the diffusion of essential molecules. For us, water fulfills this requirement. But yes, if only this is considered, other liquids could, as well.\n\nWater has a very interesting, seemingly unique, property, however. It's solid, frozen form is less dense than its liquid form. That is, ice floats on liquid water. This isn't true for many other substances that we know of. This is important, as it would seem easier for life to begin in a sea of whatever solvent is being used, aiding the new life form in finding what it needs to survive.\n\nBut what happens with temperature changes? If the temperature gets low enough to freeze the sea of solvent, and that solvent's frozen form doesn't float on the liquid, then the entire sea could freeze, and would likely kill the life form.\n\nIt also has to do with abundances. Water, being made from hydrogen and oxygen, should be more abundant than a lot of other solvents that would meet the floating requirement, simply because it's constituent atoms should be more abundant in the universe.\n\nFinally, because of life on earth, we know that life can exist using water as a solvent. I'm not aware of any life form being found that uses another solvent. Since we know it's possible to use water, looking for water as an initial indicator makes sense.",
"This is really silly, but it's the only thing we can possibly look for. Our space observation systems are somewhat rudimentary compared to what you would need to take a closer look at other planets.",
"Water is not some random chemical that we happened to evolve to use. It is the universal solvent, it becomes less dense when it freezes; the structure of the polar molecule and the ability to form hydrogen bonds is essential to life as we know it.",
"Water is often referred to as \"the universal solvent\", meaning many substances can dissolve into it. As we all know, most chemical reactions require a solution of some kind to work. Life, essentially, is just a bunch of chemical reactions. This is most likely why early organisms will always form in a \"primordial soup\" as it were. Thus, water is a brilliant \"catalyst\" to life. It's not that life can only survive with water, it is just that, where there is liquid water, there is most likely life.",
"Ammonia might be a viable alternative AFAIK",
"Water is rocket fuel",
"Right, I don't know how far down I will end up on this, already old thread, but here goes:\n\nOne quality of water that haven't been mentioned yet, and if it has, I apologize. Water has, if not the highest, then at least it's among the substances with the highest heat capacities. This means that it takes a lot more energy(heat) to change the temperature of this substance. Since life as we know it is very temperature sensitive it makes water an ample element for temperature-sensitive life to thrive in. \n\nTLDR: Water keeps status quo for longer time than other substances which is better for life to thrive in.",
"The discovery of water isn't just a huge find because of the possibility of finding life. It would also make the planet a thousand times easier for us to visit and/or colonize. Remember that water can also be converted to oxygen and hydrogen (fuel).",
"Why do we take the elevator instead of climbing up the outside of the building? If you don't see an elevator at first your thought isn't, fuck it, I'll scale this shit. It's, there has to be an elevator around here somewhere.",
" > when other forms of life could have evolved to not need water\n\nIs this something that we actually know, or is this speculation of something that MAY be possible, but may also be impossible?",
"cause we need it",
"It's easier to look for water (because we know what it looks like) than to look for another type of life (because we don't know what that would look like). ",
"Because while other forms of life evolving to not need water is possible in the \"well, it's a big universe and we know very little about it\" sense, based on every piece of evidence we have, it's really not possible. So essentially a planet with water could quite possibly have life, and one without it is probably a barren rock just like all of the other barren rocks out there.",
"Even if life itself does not require water (or carbon for that matter), life that we believe we may have the ability to interact with may require water. That is to say, a sulfur-based life form might require extreme temperatures or pressures to 'live' and we do not have a place where we can meet and interact.",
"We have ZERO proven facts about life forming in fluids other than water.\nWe know TONS about life that uses water.\n\nWe may not know \"life\" but we know what we \"are\". So we're looking for earth-like bio-systems because we don't have the understanding necessary to actually detect anything else.",
"Can't believe it hasn't been mentioned yet with all the Breaking Bad hype going around. But according to Walter White, its to do with the possibility of using the water as a source of Hydrogen fuel by separating it from the water. So that essentially the planet becomes one big gas station in space for rockets. ",
"The big deal isn't about life on other planets, but effectively turning these planets into intergalactic gas stations. See, hydrogen can be removed from the water and used for rocket fuel. This limits the amount of fuel a ship would have to carry for long interstellar trips. Instead they simply pop over to the nearest gas planet and fuel up. Water on Mars and the Moon are a big deal, because of their relative close proximity to us, so we could build ships in orbit, fuel them up from Moon/Mars water without the need of using Earth's dwindling fuel supplies, or our own water we need here.",
"So here we go\nThe abundance of various chemicals in the universe \n_URL_0_\n\nWe know that Hydrogen is most abundant, with Oxygen and Carbon being the next ones.\n\nWell let's look at human composition. We as humans and most mammals have similiar percentages, we are mostly water, H2O with guess what Hydrogen and Oxygen being the most 2 common elements\n\nAnd guess what, Carbon is the most chemically active element in all of the perodioc tables.\n\n\nSo considering the life we have seen are based upon 3 of the most abundant elements, (we ignore helium because its inert, doesn't react) \n\nSo its safe to say that we are made from the same stuff the universe is made from. Thus the universe is in us.\n\nIts safe to assume that we being the most common things. That if we find other life, that its likely to come from common things.\n\nMost likely carbon based life form, because life is complex and carbon is complex and highly reactive.\n\n\nDoes this mean, all life form is carbon based, Nope! life could be something else all together!! \nCould life have sprouted out of non 'common' elements. Sure! \n\n\n\nBut we usually target the low hanging fruit.\n\n\nAlmost all life we have ever seen and witnessed, typically thrive and do quite well or need water to survive, which isn't surprising considering that water, is Hydrogen and Oxygen and are some of the most common elements.\n\n \n\n\n\n\n",
"long story short, we don't want to find other life forms, we want to find planets where we could expand our territories to",
"Water is not so much a prerequisite of life as it is a sign that life could more easily evolve in that environment. H2O is often referred to as a universal solvent, because most things dissolve in it to some degree - something which is crucial for almost any form of life. Life which evolves without such a solvent will be limited to a much more basic level and won't be any easier to find, so we might as well search for the presence of water since that's something we can easily detect.",
"Because finding water there means we can settle there without having to bring water (heavy and expensive).",
"We are searching for the building blocks of \"Life as WE know it.\" If you don't know what you're looking for, you have no guidelines, no basis for your search. If I said find an alien. What would you look for? You would just roam around checking planets for life forms. But we're looking for planets that could harbor life as we know it. There very we'll may be life forms that have evolved as you described. But we don't know what they are or where to find them or even what to begin looking for. So we look for what is similar to us. And honestly, we're not looking to suddenly stumble upon an alien, \"hey alien Whatsup?\" We're looking for planets that can or have supported life, \"as we know it\"",
"Life as we know depends on water. I read somewhere that they found that life can be made of some kind of acid which broaden the chance of different life types.\n\nThe truth is out there",
"There is the other issue, which can be considered more important according to another agenda:\n\nfinding water on other planets means that WE might be able to live there at some point in the future.\n\n",
"Water can be made into Oxygen for breathing and Hydrogen for power. Two things we need to make all the rest of the shit we need to spread like a plague.",
"we have one example of life to go off from. that life requires water. until we find a second example that isn't dependent on water, we'll continue to be excited to find any.",
"The only life we know of lives off water. So that's where we start looking. You make a completely valid point however, there may be some life somewhere in the universe which has evolved on a completely different path living off of something completely different. ",
"This question is asked at least once a week.\n\nWater is a critical component to life developing AS WE KNOW IT. Life could exist in an infinite number of ways, but how would we know it was life? A rock on another planet could be a form of life, but how would we know, or prove it?\n\nWe are searching the cosmos for LIFE AS WE KNOW IT. Because we know how to identify that kind of life. That is why water is important.",
"Because we need a new planet. Twist: WE are the aliens. Flipped ya world over.",
"Life requires energy to work. This energy can come from various sources, but at the base of every ecosystem is something called a producer. A producer is an organism that takes light from the sun or another energy source like a thermal vent and stores that energy so that is can be used to make biomass (living matter). The only chemical reactions we are aware of that producers can use to store energy from some source are photosynthetic or chemosynthetic (using light or using chemicals). Both of these reaction types require water in order to work. Without a producer making a reaction like this happen, no life can exist because there will be no way to get energy to make the living things and keep them running. If we were to discover other chemical reactions like this that could be maintained at a cellular level (very small) that didn't require water but some other compound, we would likely add that compound to our search.\n Of course, the absence of proof of such a process is not proof that such a process does not exist, it's just that we wouldn't know what to look for without having seen or at least imagined such a process in great detail. And so, with nothing else to go on, we look for signatures of processes that we know exist. Water is a signature of all known processes, and so it is what we search for.",
"I am an Astrobiology and Paleobiology PhD student.\n\nSimply put, we don't know how to look for other forms of life.\n\nEverything that we know about life requires the elements C, H, O, N, S, and P with water as the biological solvent. A type of life made up of different essential elements and different biological solvents would display biochemistries that we are unfamiliar with. There are other problems too.\n\nTake for example an organism that is composed of Si in the place of C and undergoes some metabolic process that utilizes O2. When Terran life breathes, CO2 gas is expelled as a waste product. When this Si-based life \"breathes\", SiO2, a solid compound, is expelled. At high enough temperatures, SiO2 is liquid. However, you may realize that SiO2 or silica, is a primary component of the vast majority of rocks on terrestrial planets. The Si atom is larger than the C atom and rather inflexible in bonding potential. Reactions involving Si are much slower, which leads to slower metabolism, and thereby evolutionary processes that occur on geological, rather than biological time scales. How would you recognize that odd-looking crystal growth as an organism rather than a mineral?\n\nTo answer another component of your question though, liquid water is easier to look for than, say atmospheric gases. We are very limited in the sensitivity of instruments that can peer out into the cosmos. We are especially limited in instruments that can look at planets light years away and discern any sort of details like atmospheric composition (spectroscopy).",
"[Breaking Bad](_URL_4_) addressed this issue during the episode [Phoenix](_URL_1_) (Ep. 2 - Season 2) when [Walt](_URL_5_) meets and converses with [Donald Margolis](_URL_0_) ([Jane](_URL_3_)'s Dad) in a random bar.\n\nThe [conversation](_URL_2_) goes as follows:\n > Donald Margolis: Well played. They found water on Mars.\n > \n > Walter White: They have indeed.\n > \n > Donald Margolis: Don't exactly know what to do with that information, but, hey, God bless them, they found it.\n > \n > Walter White: Oh, well, actually, they theoretically can separate the hydrogen from the oxygen and process that into providing fuel for man's space flights. Ostensibly, turning Mars into a giant gas station. So it's a... Yeah. We live in an amazing time.\n > \n > Donald Margolis: To water on Mars.\n > \n > Walter White: To water on Mars.\n\nThe funny thing about this episode was that water had not been found on Mars during it's production or broadcast. It was a coincidental prediction in fiction, I guess.",
"For the same reason the drunk man looks for his keys under the streetlight even though he knows he dropped them further down the street: \"Because this is where the light is.\"\n\nWe know what water-based life looks like. Science does many things well, but looking for things it can't measure is not one of them.",
"ELI5: We look for life forms based around water because we don't know what else to look for. Every life form we know about comes from water. Even Arachaea, our biological superheroes, cannot survive without water as a solvent to their chemical reactions.\n\nBut, chemistry has a virtually infinite quantity of combinations that we haven't looked at yet, meaning other things we don't know about can exist. Nevertheless, considering Carbon, Oxygen and Hydrogen are the most abundant of materials in the universe, the probability of finding radically unfamiliar chemistry is smaller. \n\nBut we should always remember that atoms, our known universe, is only composed of about 5% of our actual universe. The amount of possible reactions and interactions is unfathomable. The consequence of this is that we can almost guarantee there are other forms of \"life\". We just don't know what to look for.\n\nEdit: gramer",
"Because WE need water.",
"Because we have a better idea of what conditions to look for if we want to find life that might be similar to ours. If we were to look for forms of life that don't need water, we would have no idea where to even begin.",
"Physics undergrad with an advisor who does research for NASA.\n\nIn one of our planetary science classes we were discussing this idea while going over the decadal NASA survey thing. From what I remember, the basic logic is this:\n\nFirst, all the necessary elements of life must be in the physical system. Then these elements must be able to interact with each other in a random way. If everything checks out, you have a potential for life.\n\nSo on earth, our assumption (afaik) is that these elements were in our oceans, and the currents allowed them to interact in random ways that may have formed early stages of life. Based on this assumption, we believe that the best recipe for this involves a medium in a liquid state. \n\nFrom what i remember from the statements in the decadal survey, I think it would be more accurate to say that in the particular case of mars, we are looking for water because due to the distance of mars from the sun, water is one of the only likely substances to be in a liquid state. \n\nIf we venture further out away from the sun, the temperature decreases, and the substances that we look for in a liquid form are naturally found in a gas state on earth. \n\nIIRC: There is a moon of saturn with geothermal activity and an icy surface that we believe has a liquid ocean under the surface. And jupiter also has a moon with lakes of liquid methane.\n\nAs Mistuhbull put it, its like finding a needle in a haystack. At this point our best effort is to try to identify the factors that created our \"type\" of needle. If we can identify and isolate the factors that created our needle, we might be able to find another one if we know how/where to look.",
"Water is indispensable in biochemical processes. Virtually every type of biological molecule can be broken into it's monomer parts via hydrolysis (reaction with water). I can't really understand how life would be possible without this. At least not like we know it.",
"Strangely enough, the best way this was explained to me was through a Science Fiction book called Calculating God (Robert J. Sawyer). In it, an alien that believes in Intelligent Design uses an argument based on how perfect water is for several different qualities that most other compounds lack. \nHere I quote from the book, and apologize for spelling errors as I transfer over from my kindle:\n\"Although water seems chemically simple--just two hydrogen atoms bound to an oxygen--it is, in fact, an enormously unusual substance. As you know, most compounds contract as they cool and expand as they heat. Water does this, too, unitl just before it starts to freeze. It then does something remakable: it begins to expand, even as it grows colder, so that by the time it does freeze, it is actually less dense than it was as a liquid. That is why ice floats instead of sinking, of course. We are so used to seeing that, whether it is ice balls in a beverage or a skin of ice on a pond, that we usually give it no thought. But other substances do not do that: frozen carbon dioxide--what you call dry ice--sinks in liquid carbon dioxide; a lead ingot will sink in a vat of molten lead.\nBut water ice floats--and if it did not, life would be impossible. If lakes and oceans froze from the bottom up, instead of the top down, no sea-floor or lake-bottom ecologies would exist outside equatorial zones. Indeed, once they had started freezing, bodies of water would freeze solid and remain solid forever; it is currents moing unfettered beneath surface ice that pro motes melting in the spring-- that is why glaciers, which have no such currents beneath them, exist for millennia on dry land adjacent to liquid lakes.\n[...]\nThis strange expanding-before-freezing is hardly the only remarkable thermal property water has. In fact, it has seven different thermal paramaters, all of which are unique or nearly so in the chemical world, and all of which independently are necessary for the existence of life. The chances of any of them having the aberrant value it does must be multiplied by the chances of the other six likewise being aberrant. [...]\nNor does water's unique nature end with its thermal properties. Of all substances, only liquid selenium has a higher surface tension than does water. And it is water's high surface tension that draws it deeply into craks in rocks, and, of course, as we have noted, water does the incredible and actually expands as it freezes, breaking those rocks apart. If water had lower surface tension, the process by which soil is formed would not occur. More: if water had higher viscosity, circulatory systems could not evolve--your blood plasma and mine are essentially sea water, but there are no biochemical processes that could fuel a heart that had to pump something substantially more viscous for any appreciable time.\"\n\ntl;dr: Water has several aspects that are almost exclusively unique that make life (as we know it) possible. Floating when frozen (allowing for sea-floor environments and ocean currents rather than neverending ice), expansion as it freezes and a high surface tension (allows water to break through rocks, thereby allowing the creation of soil, instead of... rocks), and a low viscosity (allowing circulatory systems to evolve).",
"Well, there is an incentive to find water on other planet's because we as a species cannot survive on earth forever and water is one of the core nutrients needed for survival. There are sects of science such as hypothetical biochemistry that attempt to scientifically validate possible life forms that do not need water, but once again, it's quite speculative and we have no empirical evidence, which is what science strives for.",
"The Atakama desert is the dryest place on the planet. 50 times dryer than the Sahara.\n\nThe desert is so dry the sand is sterile and there is no life or bacteria organism's in the sand. The complete absence of life in the dryest place on earth tells us \"life\" (even the most simple base bacteria) are non-existent in dry conditions. \n\n_URL_0_",
"So that we could sustain a society without having to import water from earth on other planets if we would be to colonize them.",
"Evolution doesn't happen over night, and water is the start of life, if we can find a planet with that, half of our goal is over, why make 3 steps when you can do it in 2.",
"This isn't likely to be the most popular answer, but I'm afraid the truth is your assertion is wrong. \"Other forms of life could have evolved to not need water\" is simply incorrect.\n\nWhile it's certainly true that you could theoretically postulate life that doesn't involve water, that uses some other materials as an environment where life could evolve in, here's the problem:\n\nThere isn't very much of those elements. Of the most common elements in the universe, only hydrogen and oxygen can form a water-like molecule. The stand-ins for Oxygen, chemically, (Sulfur) are rare. The stand-ins for Hydrogen, chemically, are even MORE rare.\n\nYou know what there's a lot of in the universe? Well, it's pretty much the who's who list of stellar fusion products:\n\nHydrogen, Carbon, Oxygen - The building blocks of organic chemistry. Those three elements, along with **inert** and thus chemically useless Helium, represent 99.5% of the observable universe. Why isn't there life that involves those four elements? 'Cuz there isn't enough of any of the other stuff to do much with."
]
} | [] | [] | [
[],
[],
[],
[],
[],
[],
[],
[],
[],
[],
[
"http://www.reddit.com/r/explainlikeimfive/comments/1ehps6/eli5_why_does_life_on_other_planets_need_to/ca0fyxg",
"http://www.engineeringtoolbox.com/specific-heat-fluids-d_151.html"
],
[],
[],
[],
[],
[],
[],
[],
[],
[],
[],
[],
[],
[],
[],
[],
[],
[],
[
"http://en.wikipedia.org/wiki/Abundance_of_the_chemical_elements"
],
[],
[],
[],
[],
[],
[],
[],
[],
[],
[],
[],
[],
[],
[
"http://www.imdb.com/name/nm0209496/?ref_=tt_trv_qu",
"http://www.imdb.com/title/tt1232247/?ref_=ttqt_qt_tt",
"http://www.imdb.com/title/tt1232247/quotes",
"http://www.imdb.com/name/nm1269983/?ref_=tt_trv_qu",
"http://www.imdb.com/title/tt0903747/?ref_=ttqt_qt_tt",
"http://www.imdb.com/name/nm0186505/?ref_=tt_trv_qu"
],
[],
[],
[],
[],
[],
[],
[],
[],
[
"https://en.wikipedia.org/wiki/Atacama_Desert"
],
[],
[],
[]
] |
||
7yy7o7 | why do combustion engines hum instead of sounding like a high rate of fire machine gun? | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/7yy7o7/eli5_why_do_combustion_engines_hum_instead_of/ | {
"a_id": [
"dujyyyv",
"duk03on",
"duk0maf",
"duk1xjq"
],
"score": [
12,
6,
6,
3
],
"text": [
"The more cylinders you have firing, the smoother the sound. Take the muffler off of an old lawnmower and listen\n",
"They're idling enough cylinders quickly enough that the sounds blend together. Most modern cars are well muffled too, and idle quietly.\n\nCars with extremely agressive camshafts and large cylinder bores built for drag racing do have an audible chop when idling. It's quite obvious in top fuel dragsters, you can even see the individual exhaust plumes from each cylinder at idle.",
"They *do* sound like a machine gun. But we attach a *muffler* to the exhaust, which removes the sound.",
"This question needs a few things to adequately address it. \n\n1. The way combustion works in a car engine versus in a firearm. In a firearm, the charge is ignited and accelerates a projectile to supersonic speeds (unless you are firing subsonic ammo), which produces a loud snapping sound as it breaks the sound barrier. Anyone who has shot subsonic rounds with a suppressor can tell you just how much of a difference not breaking the sound barrier makes. In a car, cylinders fire off in a specific firing order, often designed to limit the vibrations of the engine itself. Commonly, this can be seen (or rather heard) in the difference of the sound of cross plane versus flat plane V-style engines, with the former giving you more of that muscle car burble and the latter sounds more like a naturally aspirated Ferrari. Add to this the fact that most cars are tuned in such a way there is never/rarely any unspent fuel dumped into the headers of the exhaust, so it never backfires.\n\n2. Cars are designed to muffle sounds, whereas unless a gun is suppressed, it cares far more about the flash and recoil of the muzzle than the sound it makes. While cars have mufflers made out of materials that specifically channel the air flow in such a way that the sound is canceled out as much as possible as it exits the muffler. Without the muffler, your car engine will sound completely different. If you have ever stood next to a straight-piped car, you would notice it instantly once it is turned on or if the gas is tapped.\n\n3. The rate at which things are moving and producing sound. This ties into the first point in that in most cars, the cylinders are all firing in a predetermined sequence, often optimized for a low-vibration, smoother operation. Compare that with automatic fire on a machine gun where there is no such consideration. Now compare this with an incredibly high rate of fire weapon such as a Gatling gun and you will find that it emits a very steady sound, something like \"BRRRRRRRRRRRT!\" instead of the usual sound associated with machine guns. Keep in mind that many machine guns can fire at a relatively fast rate such as the MG42 which was nicknamed Hitler's Buzzsaw.\n\n**TL;DR:** Cars do not have to accelerate a projectile to supersonic speeds, car engines have multiple cylinders designed to fire in a specific order to lessen vibration, cars are required to have mufflers designed specifically to cancel out sound waves. You can make a machine gun hum, just get yourself a MG42 and lay down on the trigger for a few seconds."
]
} | [] | [] | [
[],
[],
[],
[]
] |
||
60nsgs | how do snowbanks not just completely melt when the temperature is above freezing? | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/60nsgs/eli5_how_do_snowbanks_not_just_completely_melt/ | {
"a_id": [
"df7tjzj",
"df7tl61",
"df7tnuc"
],
"score": [
2,
2,
2
],
"text": [
"Snow banks are more dense, the thermal mass is greater requiring a higher temperature to melt or a longer duration than the surrounding snow. best guess anyways. ",
"Water takes energy to change phase, pulling from the underlying ice as well as the air. The heat doesn't conduct into the snow instantly either so it takes a while to melt.",
"For the same reason a pot of water does not instantly boil when you place it over a flame or freeze when you put it in the freezer.\n\nWhen warm air hits the surface of the snow bank energy slowly begins to transfer from the air to the snow, thus warming up the snow and cooling the air (slightly). What happens though is, that surface snow gets slightly warmer and then immediately gets cooled by the internal snow it is touching. The snow only begins to melt when the snow that it is touching is unable to absorb more energy before itself melting. \n\nThis is often why if you live in a city you will see workers destroying snow banks on warmer days to spread the snow out thereby increasing surface area by which the air can warm the snow more efficiently to melting point. "
]
} | [] | [] | [
[],
[],
[]
] |
||
1dal5e | why aren't products like 5-hour energy evaluated by the fda? | They make the point, as required by law I'm sure, to include the disclaimer "*This statement has not been evaluated by the Food and Drug Administration. This product is not intended to diagnose, treat, cure or prevent any disease." on their products and advertisements.
Why aren't they evaluated? Is there a general set of foods/medicines that are, and products like these simply fall outside the scope of the FDA? Or do these companies specifically avoid getting their products inspected? Is there anything else behind it?
I haven't found anything like this on Reddit or Google yet, so I figured I'd post here. | explainlikeimfive | http://www.reddit.com/r/explainlikeimfive/comments/1dal5e/eli5_why_arent_products_like_5hour_energy/ | {
"a_id": [
"c9ohht7",
"c9ohie8"
],
"score": [
3,
4
],
"text": [
"They aren't reviewed because they make a point of saying that the product isn't intended to treat any disease. If they claimed to alleviate sleeping sickness the FDA would crack down on them. That's also why anti-aging creams say \"not for surgical results\" in the ads, and why Cheerios had to change their slogan a few years ago. The FDA told them that if they claim Cheerios are a treatment for high cholesterol, then they were legally a drug (_URL_0_).",
"If a product claims to address a medical condition, it is classified as a drug, and must undergo intensive FDA before it can be marketed, and even then might require a prescription. So what these products are doing it making it explicitly clear they are not drugs, so the FDA doesn't come after them.\n\nFood and supplements are also investigated by the FDA, but only for safety. The general rule is if it is naturally occurring, not dangerous, and there is no specific law against, you can sell it was a supplement."
]
} | [] | [] | [
[
"http://latimesblogs.latimes.com/money_co/2009/05/fda-warns-general-mills-over-cheerios-cholesterol-claims.html"
],
[]
] |
|
6453fy | how does eating lots of sodium make us bloat and what happens to our body if we lack salt? | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/6453fy/eli5_how_does_eating_lots_of_sodium_make_us_bloat/ | {
"a_id": [
"dfzi4v4",
"dfzm8kb"
],
"score": [
5,
3
],
"text": [
"Eating a lot of sodium makes us bloat because it triggers reabsorption of water in the kidneys. The body likes to maintain certain concentrations of different salts (concentration meaning: amount of salt per volume of water), so if we have a high amount of salt, our body will retain water because it needs to maintain a certain osmotic pressure, which is basically a \"sucking\" force caused by salts that attracts water.\n\nIf we lack salt, our body will expel more water to maintain the correct salt levels. We will also crave more salty foods. Sodium is important for our nervous system to function.\n\nVarious hormones control salt and water reabsorotion in the kidney.",
"There are different kinds of salts. The important ones are sodium salts, potassium, magnesium, phosphorus etc. Our bodies use sodium and potassium ion channels in our nerves for transmitting nerve impulses. We need them to live. We excrete salts from our sweat and people who sweat a lot, but only drink water to hydrate will eventually cramp up and get very ill because they lose too much salt and aren't replenishing it. \n\nIt can kill in extreme cases. You get muscle weakness, tremors, cramping, nausea, irregular heart rate, confusion, headaches, seizures, basically your bodies electrical system goes haywire and once your heart isn't beating correctly because the nerve controls are failing, you're done for. This is one of the reasons why sports beverages like Powerade contain \"[electrolytes](_URL_1_)\" aka salts. \n\nOn the other hand, too much of a good thing is bad. If you cut out water, and ONLY drink Powerade, you will put too much salt into your body. It's mostly sodium (correction) but has potassium as well. Your body can correct this to an extent by getting rid of it in sweat and the rest is filtered by your kidneys and you pee it out. But this takes time. \n\nIf your sodium levels are elevated for a long time, say from powerade binging, you will begin to retain more water in your flesh. This causes swelling or edema, and it makes your heart have to work harder and raises your blood pressure. The reason for this might require more than an ELI5. It's called the [renin-angiotensin system](_URL_0_) and it has to do with the triggers your body uses to regulate water and sodium intake. \n\nSuffice to say your body looks for a signal that it needs more sodium, and this signal triggers thirst and also causes the body to hold onto more water. There are other signals and triggers that tell your body it has too much sodium or water, and it will begin expelling both through urine. This is how diuretic medications work, by tricking the body into thinking it has too much sodium, and the water is expelled along with it. Sodium and water regulation are hand in hand in the body and one is tied to the other. \n\n"
]
} | [] | [] | [
[],
[
"https://en.wikipedia.org/wiki/Renin%E2%80%93angiotensin_system",
"https://www.youtube.com/watch?v=-Vw2CrY9Igs"
]
] |
||
4qog54 | how does gambling in cs:go work? how does _url_0_ facilitate this? how do you "place your bets" if you are playing on a console? how does the money get transferred to the winner after a victory? | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/4qog54/eli5_how_does_gambling_in_csgo_work_how_does/ | {
"a_id": [
"d4umukg",
"d4un2vo"
],
"score": [
2,
2
],
"text": [
"Gambling is usually done with in game weapon skins. Valve allows you to buy, sell, and trade skins between friends or on the community market. \n\nThe way gambling works is a user will buy or earn skins, gamble them, and if they win, they get some amount of skins that the losers bet, and if they lose, their skins are gone. The sites usually function as an escrow service, where you send the skins to the website, make a gamble, and the site send them back plus your winnings if you win.\n\nMoney isnt actually used, but because CS skins have a highly liquid market, users can easily buy some skins, gamble them, then sell the winnings to go back to cash.",
"Since I was gambling, I know how it works: \n\nYou buy skins on the steam market, which have a specific value, that varies depending on supply and demand. You can now transfer those skins to any CS:GO Gambling Service instead of real money and use them for games like rock, paper, scissor, roulette, etc.. \n\nAfter you win, you just simply get skins from your opponent for example which you can transfer back to your Steam account.\n\nThey faciliate this by using bots which send you Steam trade offers to your Steam Account with the skins, you wanna use as \"bet currency\". Usually with a confirmation code only you can see. \nAnd furthermore, if you win, they are likely to take for example 10% of the skins you won for themselves. \n\nAbout the console part, if you can access the Steam Market and can buy skins there, it should be the same. \n\n"
]
} | [
"https://kickback.com/"
] | [] | [
[],
[]
] |
||
donefa | what happens to the physical money when doing international transfers? | Imagine you deposit $1000 cash in the US into your bank account at bank A. Then you transfer the money to your partners account in Germany at bank B and your partner withdraws the equivalent amount of money in euros.
What happens to the cash when sending money from Bank A to Bank B? | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/donefa/eli5_what_happens_to_the_physical_money_when/ | {
"a_id": [
"f5p02av",
"f5p075s",
"f5p0oe8",
"f5pbebi"
],
"score": [
4,
21,
2,
3
],
"text": [
"They stay at the bank you deposited. What is “transferred” is the data stating how much you have. If you pull from another bank it basically comes up as an IOU from your bank to the one you pulled from, that they will pay off with the money in your account. At least that’s how it was explained to me.",
"In the most simplistic terms. Your bank in the US will have a contract in place with a transferring bank in the US. They will do an electronic transfer to the Transferring US Bank. The transferring bank in the US with agree a transfer with a Transferring Bank in Germany and the Transferring bank in Germany will do a transfer to the Destination Bank. \n\nSo in-country bank to bank transfers don't involve trucks driving around with bank notes and change for every transfer. The transfer is electronic and the bank will keep a electronic record of the total balance of transfers between them for all their client's transactions (in both directions) and will balance this out from time to time in a variety of methods. In the old days this used to be physically transferring gold between them. Now-a-days it is more likely to be bonds being transferred, but can be stocks, gold, options, property or balances held at other banks and also actual cash obviously.\n\nInternational bank to bank is pretty much the same. The Transferring Banks will agree to buy/sell Euros for Dollars at a particular spot exchange rate. The books between those banks will get balanced from time to time but the immediate consequence for your individual transaction is that the German Transferring Bank will take an IOU from the US Transferring Bank.",
"The amount of money (digital and cash) on the market is controlled by a central bank for each region. In Europe it's the european central bank. They usually can see the overall amount of money and can take measures to keep a certain percentage of that in cash on the market, like printing new and destroying old cash. The overall amount of money is controlled via a head interest the banks get for money they hold or must pay if the interest rate is negative.\n\nThe overall goal of central banks is to balance the amount of money with respect to the economy of a region.",
"Every (or nearly every) country in the world is operating on a fiat currency. It's all make-believe based on nothing of substance. When you transfer money to another country it's just sending 1's and 0's from one computer system to another and the banks just hold on to physical cash until someone requests physical/paper currency."
]
} | [] | [] | [
[],
[],
[],
[]
] |
|
otzzs | the definition of a tax | I know what a tax is but I want to know the difference between 3 types of specific taxes: A proportional tax, a regressive tax and a Progressive tax. My economics teacher couldn't really explain it well.. | explainlikeimfive | http://www.reddit.com/r/explainlikeimfive/comments/otzzs/eli5_the_definition_of_a_tax/ | {
"a_id": [
"c3k1uvh",
"c3kc35s"
],
"score": [
4,
2
],
"text": [
"Proportional tax is a fixed rate for everyone. A progressive tax increases your tax rate as you make more money. A regressive tax decreases your tax rate as you make more money.",
"Explained well by ameoba, here are some examples that might help you understand\n\nProgressive Tax: Federal Income Tax, as you earn more you pay a higher rate\n\nRegressive: Plastic Bag Fees (Called a Sin tax), These taxes tend to hurt the poor because no matter how much money you have you have to pay that same amount\n\nProportional: Sales Tax (within each state), no matter who you are...you pay the same *rate* (5%, 6%...)"
]
} | [] | [] | [
[],
[]
] |
|
98ehyn | why is the term "austerity" seemingly never used in the us? | I constantly hear about austerity measures to reduce debt and such in European countries, but in the United States, I never hear conservatives/Republicans use the term "austerity" to describe reducing government spending. Instead they call it "fiscal responsibility" or "measures to reduce the deficit" or "reducing the national debt".
Why does the US seem to not use the word "austerity"? Or do they use it and I've just been missing it? | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/98ehyn/eli5_why_is_the_term_austerity_seemingly_never/ | {
"a_id": [
"e4fdcga",
"e4fddsa",
"e4fj2m9",
"e4qokx4"
],
"score": [
14,
4,
3,
2
],
"text": [
"Because our budget is so far from austere it would be absurd and they might be mocked. Both major parties support spending that is hundreds of billions of dollars beyond the amount we collect in taxes.",
"Because austerity is something someone imposes on you because they want their money back and you've signed agreements to give it back to them in their own currency. You bail them out, you set terms on your bailout, and they have to cut social services WAyyyy back to meet the terms of your bailout. This is not as good for the average citizen as simply ceasing to pay debts, but the (extremely) negative impacts are streched out over much longer periods of time and the government can stay in power because most people aren't starving in the streets.\n\nThe USA has never had to borrow in a foreign-controlled currency and therefore has always had the ability to inflate it's debt away. There has never been a force more powerful than America that was able to force America by violence or threat of violence to repay it's debts. Also involves good money management, which is questionable these last 30 years, so you'll probably see a USD monetary collapse in your lifetime.",
"Because the US is able to pay off its debts and there is no reason to believe this won't continue. Austerity starts when a country is in danger of not paying its debts.\n\nFiscal responsibility is \"the balance on our credit card is getting high, let's try to manage it a little better.\"\n\nAusterity is \"they are about the foreclose on the house...sell the car, get a second job, eat nothing but beans and rice, do whatever it takes to keep the house!\"",
"'Austerity' is meant to make budget cuts sound negative, and European politicians use it when they are trying to appeal to a broad majority who are against shrinking their governments.\n\nIn the US, a majority of people like the idea of cutting government spending, so a general budget decrease is hard to demonize. American voters tend to be delusional about how much we could save by trimming the specific programs they are not fond of, and theoretically support a balanced budget so long as their favorite agencies are untouched.\n\nEven our Lefties like to imply that they are open to general budget cuts, only to run around reassuring special interest groups that *their* programs are totally necessary, but there are plenty of other agencies that need reduced."
]
} | [] | [] | [
[],
[],
[],
[]
] |
|
a5llob | if astronauts on orbit around earth experience 0g because they are technically falling back to earth, would they still be experiencing 0g when flying through deep space or would they be in total 0 gravity? | That might be awkwardly worded, so let me try to expand. When flying in deep space, let's just say to Mars, and not on orbit around the Earth, are they then experiencing true zero gravity as opposed to zero G?
I hope that makes sense.... | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/a5llob/eli5_if_astronauts_on_orbit_around_earth/ | {
"a_id": [
"ebngvfp",
"ebni409",
"ebni91q",
"ebni9sw",
"ebnnmvm"
],
"score": [
9,
6,
3,
3,
2
],
"text": [
"There is no 'true zero gravity'. Zero G and zero gravity are the same thing. Astronauts in orbit are in free fall around the planet, and so experience zero gravity. If an astronaut was to travel to, say, Mars, they would essentially be in free fall _towards Mars_. The effect is the same.",
"It's basically the opposite, in a way.\n\nFree fall or \"zero g\" as we tend to colloquially call it, is essentially having no force act on you *except for* gravity. Which obviously is a bit counter-intuitive. \n\nAstronauts in orbit, or in a non-accelerating spaceship, would both experience this. In essence, they're just 'moving in the same direction as the ship' and there's no other force pushing them one way or another. Hence they can essentially float within the ship.\n\nConversely, if your spaceship were to begin accelerating, the back end of the ship would catch up to the non-accelerating astronauts, and shove them forward, accelerating them. Now they're under a force other than just gravity. But again, counter-intuitively, what this would look like to the astronauts is that suddenly the 'back of the ship' is the floor, and they're now held to it, *as though* it was exerting a gravitational pull. \n\nIn short, freefall isn't an absence of gravity, but rather it's the absence of a contact force, a force where *some thing* pushes *some other thing.*",
"There is such a thing as true 0 gravity in a theoretically void space. However everything will have some gravity so zero gravity is just theoretical as opposed to microgravity. As for the effect of freely orbiting another body this is as you say not really 0G, or even microgravity. The astronauts on ISS is not having much less gravitational acceleration then here on Earth. However it is impossible to feel the effect of gravity. Your body and most of the effects of gravity comes from the normal force. The normal force is just the name of whatever force opposes gravity making sure you do not fall through the center of the Earth. And if you think about it you do not feel anything pushing you down but you can feel the ground pushing you up. So when we conduct freefall experiments, either in drop towers, vomit comets or on spacecrafts, we are not looking at removing the force of gravity but rather removing the normal force.",
"In practice yes, in theory not *really*.\n\nGravity's reach extends out to infinity from all bodies with mass, but it falls off enough so that if you're far enough away from anything with considerable mass, you are effectively feeling no gravity from it/the amount of effect its' gravity has on you rounds to 0 for all practical applications.\n\nIn the instance of flying to mars, you won't be in an orbit around a planet, but you will be in some orbit around the Sun, and therefore will have the same free-fall experience from your (much further away) solar orbit.\n\nBut yes if you're in deep space, not near any body of appreciable gravity and not accelerating you will experience \"true\" zero gravity (or near enough), and not a simulation of it due to the consistent free-fall that is orbiting the Earth.",
"The thing to remember is that *everything* is in orbit, all the time. There is no such thing as a free moving object or a straight line course in space. If you send a rocket to Mars, even after it leaves Earth's influence (that is, Earth is no longer its dominant gravitational body), you've still got to account for the velocity it had as part of Earth's orbit around the sun.\n\nWhen you travel to Mars, what you're doing is manipulating the shape of your orbit around the sun such that your orbit intersects Mars' orbit when and where Mars will be at that point in its orbit.\n\nAs Voyager II leaves the solar system, at some point it will leave the sun's influence - but it will still be carrying the velocity of solar system with respect to the galaxy. If it were to navigate to Alpha Centauri, what it would need to do is manipulate the shape of its orbit around the galactic center such that its orbit would intersect that of Alpha Centauri when and where Alpha Centauri would be at that point in its orbit.\n\nAnd so forth, out to any scales you pick.\n\nNow, obviously, the further away the thing you're orbiting around, the longer your orbit, and the closer to straight it seems at human scales. But it's never actually straight; nowhere is free from gravity.\n\nAll of which is by way of answering your question - the zero gee the astronauts feel aboard the ISS is exactly the same as the zero gee they would feel *en route* to Mars. Because the ISS is in constant free fall towards Earth, the astronauts experience no net force relative to their frame of reference (the ISS). Because the Mars ship would be in constant free fall towards the sun, the astronauts would experience no net force relative to their frame of reference (the Mars ship)."
]
} | [] | [] | [
[],
[],
[],
[],
[]
] |
|
p4bva | the harlem globetrotters | The most obvious questions: Why does anyone agree to play them? Are they in their own personal league? Do they exist in parallel universe where it's cool to get your ass kicked? Are they really that good at math? | explainlikeimfive | http://www.reddit.com/r/explainlikeimfive/comments/p4bva/eli5_the_harlem_globetrotters/ | {
"a_id": [
"c3mdz43",
"c3mei2k",
"c3mej62",
"c3mev85"
],
"score": [
3,
7,
13,
3
],
"text": [
"They're the post-'School of Rock' Jack Black of professional Basketball. They're just...there. ",
"They play the Washington Generals every game, who I *think* are just paid to play shitty basketball. It is more a performance than a basketball game. \n\nEDIT: Generals, not Nationals. The Nationals are paid for playing shitty baseball.",
"They do not play basketball, they perform and exhibit skills associated with playing basketball. The performance is usually framed in the context of a competition. It is no different than professional wrestling, a demonstration. The demonstration is more impressive if it seems to lead to a \"win\" so the scripted game is a added.",
"Never bet all your money against the Globetrotters."
]
} | [] | [] | [
[],
[],
[],
[]
] |
|
3cikay | why are cases of statutory rape treated differently when the victim is male and the perpetrator is female as compared to a female victim and a male perpetrator? | _URL_0_
_URL_1_ | explainlikeimfive | http://www.reddit.com/r/explainlikeimfive/comments/3cikay/eli5why_are_cases_of_statutory_rape_treated/ | {
"a_id": [
"csvvgly",
"csvvgrx"
],
"score": [
6,
8
],
"text": [
"Because social and cultural norms place the onus on males. There have been sweeping changes as of late, and male statutory rape victims of statutory rapist women are being vindicated by the changing tides. However, every once in a while there are weird things, like that first link, there. Because he did not report it as a crime, and he was on the cusp of legality in his state, many years later, when the statute of limitations has passed, THAT happened.\nIt's unfortunate, but if you do not report a crime, nobody -knows- it happened, and there's nothing that can be done about it.",
"Because all rape is treated differently when the victim is male. There is an assumption within society that men always want sex and that assumption makes many believe that men cannot be the victims of rape. This belief is so pervasive that some countries codify it in law. \n\nThe UK requires a victim of rape to have been penetrated. If you were not penetrated you are the victim of the lesser crime of \"sexual assault\". \n\nThe Australian hotlines for abuse victims have a hotline for women who are the victims of rape or abuse, but the hotline for men is for those who think they are abusers. \n\nIn virtually all developed nations the resources for male rape victims in the form of counseling, shelters, and the like are between 1/10th and 1/5th the amount available to women despite the fact that men make up between 30%-45% of rape and abuse victims. \n\nMale rape and domestic abuse victims are basically ignored by society. It is horridly sexist reality but it is the reality. "
]
} | [] | [
"http://www.huffingtonpost.com/2014/09/05/nick-olivas-alleged-rape-victim-_n_5773532.html",
"http://baltimore.cbslocal.com/2014/04/14/police-man-25-charged-with-statutory-rape-of-pregnant-13-year-old-girlfriend/"
] | [
[],
[]
] |
|
9nq6eb | why isn't libertarianism well received in politics? | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/9nq6eb/eli5_why_isnt_libertarianism_well_received_in/ | {
"a_id": [
"e7o7yik"
],
"score": [
3
],
"text": [
"Libertarianism (in the right-wing North American sense) has often been compatible with the Republican Party (US) or the larger right wing parties in Canada (the modern Conservative Party is a merger between the old Progressive Conservatives and the Alliance Party, who were actually the Official Opposition for a while back when they were called the Reform Party). It tends to be easier for rightwing ideologies to find common ground, despite their differences, than Left-wing ones (as a leftist, my least favourite thing about leftism is the tendency towards ideological infighting). \n\nNot many people know this, but the first people to call themselves \"libertarians\" were French socialists in the 1850s... it wasn't until the 1950s that laissez-faire capitalists started calling themselves that. The most well known \"Lib-soc\" in the modern day is probably Noam Chomsky. _URL_0_"
]
} | [] | [] | [
[
"https://en.wikipedia.org/wiki/Libertarian_socialism"
]
] |
||
41my2b | how is it possible to hold your breath longer underwater than on land? | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/41my2b/eli5_how_is_it_possible_to_hold_your_breath/ | {
"a_id": [
"cz3lr4v",
"cz3lx38"
],
"score": [
435,
46
],
"text": [
"You are correct. [Mammalian Diving Reflex](_URL_0_).\n\nBasically, when our ears are immersed in water, our heart rate automatically slows down, slowing oxygen usage and allowing us to survive longer underwater.\n\nRelated, this is why splashing cold water in the face of someone panicking calms them down. Slapping them does not. ",
"How long you can hold your breath depends on how quickly your body uses oxygen, and on how quickly your body produces carbon dioxide. For the sake of simplicity, let's say those two are roughly equal. \n\nFloating underwater, your muscles don't burn up energy keeping your body upright and balanced. But, it turns out, just *being* underwater has a large effect on your metabolism due to the mammalian diving reflex. This reflex slows down your heart rate and reduces blood flow to your extremedies. Both of these effects stretch out the usefulness of the oxygen in your lungs and in your blood. Our bodies evolved \"knowing\" that air is hard to get underwater, so if we find ourselves submerged, we need to hold on to what we've got. Above water, who cares-- just take another breath, bozo. "
]
} | [] | [] | [
[
"https://en.m.wikipedia.org/wiki/Mammalian_diving_reflex"
],
[]
] |
||
7jzv23 | why do phone games uses multiple in-game currencies? sometimes a more valuable currency is used to encourage you to spend real money but are there other reasons? | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/7jzv23/eli5_why_do_phone_games_uses_multiple_ingame/ | {
"a_id": [
"draep48",
"drafk3c"
],
"score": [
8,
2
],
"text": [
"\"Sometimes a more valuable currency is used to encourage you to spend real money but are there other reasons?\"\n\nNope, you got it right there.",
"As a general rule, most games will have \"in game\" currency that you can earn to buy stuff and \"purchasable\" currency that can be exchanged for in game currency. The idea is that by creating degrees of separation between the idem you are actually buying and the money you are spending, they can make it easier to spend money.\n\nIf I were to say, \"You can buy Item X for $0.99\" people may not feel item X is worth that kind of money. However, if I let you buy 4500 diamonds for $4.99, then have Item X cost 895 diamonds, it is harder to figure out exactly what Item X costs in real dollars (its about $0.99).\n\nBy making is harder to do the conversion, you are less likely to associate the spend with real money. \n\nThere also value in just the separation of currency itself - it is easier to spend diamonds than dollars in our minds since we don't see diamonds as real money. Casinos figured this out years ago - people will bet $100 in chips much easier than $100 in cash."
]
} | [] | [] | [
[],
[]
] |
||
4fns5j | how would a constant radio transmission be received from an object moving away in space? | If a ship was constantly broadcasting a signal back to earth, as it moved farther and farther away, how would the signal be received back on earth? Would there be gaps in the transmission? The further you go, the longer the time between transmission and reception. I'm curious to know how it would work with an uninterrupted broadcast, from somewhere with zero delay, out to the edge of the solar system. | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/4fns5j/eli5_how_would_a_constant_radio_transmission_be/ | {
"a_id": [
"d2aewoz",
"d2af908"
],
"score": [
3,
2
],
"text": [
"There wouldn't be \"gaps\", as you put it - but you're not far off.\n\nCommunication usually takes the form of radio waves, and what happens is the waves get stretched out - the wavelength goes up, and the frequency goes down. This is known as \"red-shifting\", because white light gets slightly redder when it gets stretched in this way.\n\n\"The Doppler effect\" is the general name for when waves get changed in this way, and it includes red-shifting when things get further apart, and blue-shifting when they get closer together.\n\nWe can see the Doppler effect in lots of places, but the most obvious one is when you listen to a car going past. As it passes you, its sound becomes lower in pitch. That's because when it's moving towards you, its sound is blue-shifted, and when it's moving away, its sound is red-shifted.",
"In this case, sound would make a good analogy. Think of an ambulance with its siren on. As it moves away the sound will be uninterrupted but will lose volume. This happens as the sound gets \"spread\" over a larger area because the siren emits in all directions. In space, we would use emitters that send focused beams for long distance transmission to prevent power loss. Also if the emitter is moving we would also have Doppler shift effects lowering the frequency of the signal as the emitter moves away. The closer the speed to the speed of light, the more noticeable the effect.\n"
]
} | [] | [] | [
[],
[]
] |
|
39f4gd | do the religious people who spontaneously start speaking in tongues believe they are using language, or do they know they're just making up gibberish? | explainlikeimfive | http://www.reddit.com/r/explainlikeimfive/comments/39f4gd/eli5_do_the_religious_people_who_spontaneously/ | {
"a_id": [
"cs2udlk",
"cs2uetl",
"cs2usve",
"cs2vdvf",
"cs2vfka",
"cs2wpqh"
],
"score": [
3,
3,
2,
2,
2,
2
],
"text": [
"The formal term for speaking in tongues is Glossolalia. Among religions that use glossolalia, the official explanation goes both ways.\n\n1) Some people believe it's a miraculous effect, caused by being \"filled with the holy spirit. Opinions vary over whether it's gibberish, a kind of divine language, or real human languages that the speaker doesn't know. Linguistic studies suggest it's gibberish - there are no clear words or associations of sounds with concepts, and the speaker never uses sounds that are not in their native language.\n\n2) Others believe that miracles no longer occur (a belief called cessationism), but engage in glossolalia as a part of worship.\n\nI don't doubt that there are people who speak in tongues due to fit in, but know they're just making up gibberish - but it's very hard to get people to admit to that sort of thing, and to my knowledge it hasn't been studied.",
"In modern Pentecostal/Charismatic churches, they absolutely believe it is a real language. It might be a language on earth or a language used by the angels in heaven, the speaker really doesn't know. The speaker also has no idea what the message is of what they are saying. The people in the church will usually all pray in tongues at the same time during every worship service, and this is not considered to have any special meaning other than worshipping God. Once in a while someone will feel compelled to stand up and loudly deliver a message in tongues for all to hear. At those times the whole church will listen quietly even though no one has any idea what is being said. Sometimes another person in the church will stand up afterwards with a translation of the message, also inspired divinely since that person doesn't know the supposed language either. It is considered very fortunate and blessed by God when a message is translated. It doesn't happen very often. ",
"It seems kind of stupid. In fact, in the Bible, the phenomenon of the miracle was that the men started speaking, and people who did not actually understand the language of the disciples heard the message as if it were being spoke in their native tongue. Other times, they started speaking in languages they themselves had never heard before, yet someone who knew the language they were speaking in understood the message. \n\nI think the people bursting out in \"tongues\" really *believe* they are speaking in a real language, but in reality, God wouldn't be encouraging it unless there were people in hearing range who didn't speak the local language and needed to heard the message. And then the miracle of tongues would manifest for them. Seriously, it really makes no sense to me.",
"My impression of the phenomenon is more of a trancelike state. I'm not sure if they're \"aware\" of what they're saying any more than you might if you were hypnotized and told to speak Welsh (without knowing welsh). If you watch them, it looks like they're in a trance, slightly swaying, eyes closed, and having an estatic expression on their face. ",
"In my experience they absolutely do believe they are speaking a mysterious 'angelic language'. \n\nSome of them are encouraged to deliberately try making nonsensical words with the idea it will help them receive and communicate in the 'real thing'. (so in a small way they just believe the 'kickstarter' is gibberish).\n\nI've had some others agree that it may start or be partly 'gibberish' but they insist this is not 'purposefully' but its just that the speaker is having trouble 'letting out the pure language'.\n\nIn a sense I suppose half my mandarin is 'gibberish' to the listeners though I do believe I'm trying to speak the real language heh.\n\n To me it's just a baffling thing. Charismania. I don't think its helped the church or the people trying to do it. I think they are confused and misunderstanding some things but generally speaking they DO BELIEVE - sincerely - they do believe something good and real is happening. \n\n*for the record Hindus were doing something like in those 'ashrams' or whatever its called for a long time Im told. ",
"Funny story a buddy of mine who know greek and latin told me once. He went to a church whose main attraction was people speaking in tongues and the pastor would translate. He got up in the middle of a session and said something in greek (l might be wrong on the lauguage but it was whatever everyone else was using) the pastor translated it as some random proverb , immediately he got back up and said \"I just said If you can't understand this you're a fraud\""
]
} | [] | [] | [
[],
[],
[],
[],
[],
[]
] |
||
1mv228 | when does my generation stop and the next one start? | is there a actual time span to this? (for example 10 years) and what is the range for my generation?
| explainlikeimfive | http://www.reddit.com/r/explainlikeimfive/comments/1mv228/eli5when_does_my_generation_stop_and_the_next_one/ | {
"a_id": [
"cccuxgq",
"cccv1hw",
"cccv1lp",
"cccvure",
"cccwpe2"
],
"score": [
2,
8,
5,
2,
4
],
"text": [
"i thought it was based off the decade you were born in, like 90's kids and 80's kids. if you were born later in the decade you simply round up. just my opinion but i hope it gets you closer to the answer",
"In a lot of ways, trying to pigeon hole this is arbitrary and debatable. There is certainly nothing \"official.\" That said, you'd be safe ticking off a generation every 20 - 25 years or so. So in the US:\n\nBaby boomers born in the late 40s to the early 60s.\n\nGen X born from late 60s early 80s.\n\nMillennials born in the late 80s and 90s.\n\n... ish. ",
"There are different types of generations.\n\nGeneration is simply a group of individuals living around the same time.\n\nSO there is of course the 90's generation, the 80's generation, etc.\n\nBut at the same time you might have the WWII generation, the Korean War Generation all the way up to the War on Terrorism generation.\n\nYou could say that we are the technological generation, and our parents are the Social Revolution Generation, our grandparents were the Civil Rights Generation, etc.",
"There is no number, but it depends on the economic-cultural zeitgeist of when you spend your formative years.\n\nThere is a theory that there is a 13 year rock/pop cycle, where harder/indie rock will predominate in the trough of the cycle, and that pop will predominate at the peak. You could fit your generation into which cycle. \n\nIn my observations, as the decades change, the zeitgeist changes, usually 1 year in. (1971, 1981, 1991, 2001).",
"I've spent a lot of time thinking about this, and after a little more thought I think I've organized my thoughts to a point where other people can understand them.\n\nI don't think generations are an actual tangible idea but more of a state of mind. Times during which many people have extremely similar experiences, such as growing up during the Cold War with the fear of a Russian attack and bombing drills in school. Other extreme events like the birth of radio, television, and mainstream Internet. Also things like the major shifts from rural to city life in the 17-1800's.\n\nThese experiences lead to the famous \"Back in my day...\" speeches, such as you spending all day watching tv while your grandfather was working at 15, and boy did he let you know. Basically a general feeling of \"you people are like me\".\n\nEven things as small as tv shows, (I'm thinking Rugrats, Rocket Power, Dexters Lab, etc.) kids that grow up these days without those shows, I don't believe are in my generation.\n\nEven my coworker who is 19, I am 21, I feel like he is just barely in my generation. Hope that explains how I feel. Sounded better in my head."
]
} | [] | [] | [
[],
[],
[],
[],
[]
] |
|
36l74u | do extreme supplements such as emergen-c (1000% vitamin c) actually help to get rid of colds faster? | explainlikeimfive | http://www.reddit.com/r/explainlikeimfive/comments/36l74u/eli5_do_extreme_supplements_such_as_emergenc_1000/ | {
"a_id": [
"crexfgc",
"crexi57",
"crexkc6"
],
"score": [
6,
6,
2
],
"text": [
"In short - there is absolutely no scientific evidence to suggest that colds are affected by any supplement especially vitamin c.\n\nThis myth endures because there was a famous scientist that believed it - but it hasn't proven to be true",
"No. Vitamin C is only supposed to effective in helping to prevent a cold BEFORE you get it. If you get a cold, it's too late. Taking any dose of Vitamin C will definitely not help you to get rid of it any faster. ",
"_URL_0_\n\ntl;dr version is no. Not to the degree that people hope.\n\nSome vitamin c is important for good health, but unfortunately there is a point of diminishing returns. "
]
} | [] | [] | [
[],
[],
[
"http://lpi.oregonstate.edu/mic/vitamins/vitamin-C"
]
] |
||
13ualu | what stops drinking bottles from exploding? | Hey Reddit.
I just poured myself a glass of sparkling water. As I poured and the pressure in the bottle lowered, it dented alot and scrunched up the bottle. Before the air outside was allowed to push the bottle back to its original state, I screwed the lid onto the bottle. After a short time, the air production of the water pushed the dents out and filled the bottle with gas to the point which I couldn't compress the bottle with my hands. So I was wondering, what stops this gas producing once the bottle is full of it? And why doesn't pressure cause the bottle to explode? | explainlikeimfive | http://www.reddit.com/r/explainlikeimfive/comments/13ualu/what_stops_drinking_bottles_from_exploding/ | {
"a_id": [
"c7788ow"
],
"score": [
5
],
"text": [
"The pressure doesn't cause the bottle to explode because the bottles are designed to hold up to the amount of pressure exerted.\n\nWhen the pressure gets high enough, the amount of gas dissolving back into the water becomes equal to the amount of gas leaving the water, so there's no overall change."
]
} | [] | [] | [
[]
] |
|
6kfss8 | why is happiness fleeting, but sadness is constant? why do humans have to strive to achieve happiness but default to sadness? | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/6kfss8/eli5_why_is_happiness_fleeting_but_sadness_is/ | {
"a_id": [
"djlyrw0"
],
"score": [
10
],
"text": [
"Different cultures and people define what happiness and sadness is. Some people think always achieving more is happiness so they feel sad if they stop achieving things. They think sadness is losing things. There was a study of an isolated culture that were very happy because they didn't understand the idea of success equals happiness. To them being alive is happiness. Studies of the least happy countries often have stressful societies that tell them this life is key to happiness when it clearly isn't the case for everyone.\n\nIn reality emotions can be triggered by sudden gains or losses but to continue that feeling is a choice. Let's say you lose something that is bad for you, society says loss is sadness. But that loss could be happiness. \n\nEmotions are just chemical reactions and our own preconceived ideas of what they are. Myself has chosen to not live in sadness or fear, so I try to find the positive in everything. Life will always have gains and losses, but that is life, and it should not control my emotions.\n\nI would also like to add anger because anger management is about realizing your anger at that moment and choosing not to engage in it. Part of controlling emotions and recognizing them and accepting them because everyone will experience a variety of emotions."
]
} | [] | [] | [
[]
] |
||
dj7g4k | if frequency changes only the pitch of a sound, what affects "how" it sounds? in other words, how do the soundwaves coming from a piano differ from the soundwaves of a violin, if they're playing the same tone? | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/dj7g4k/eli5_if_frequency_changes_only_the_pitch_of_a/ | {
"a_id": [
"f41ujvy",
"f41vwwc",
"f41w942"
],
"score": [
4,
3,
2
],
"text": [
"In addition to the dominant frequency (aka the pitch you hear) there are harmonics at play. Wood resonates differently than metal and thus creates different harmonics.",
"Sound isn't just one sound wave. Well, most of the time it's not. [here](_URL_0_) is a 10 hour long video of what a single sound wave sounds like. \n\nWhen most things make noise, they're actually making a bunch of different sounds all at the same time, and it's the combinations of these sounds that our brain interprets as affecting the quality of a single tone. We hear one dominant tone which is the note so to speak, and then all the other tones affect how our brain perceives that tone.",
"You’re almost never hearing a single pure frequency. When you play a violin you aren’t just hearing the string vibrate, you hear the body and the finger board and the bow and so on. You’re hearing various other frequencies on top of the main one. It’s also worth noting that the very beginning of a note, the *attack* is what really allows us to tell the difference between instruments. A lot of instruments sound the same if you clip out the attacks."
]
} | [] | [] | [
[],
[
"https://www.youtube.com/watch?v=xGXYFJmvIvk"
],
[]
] |
||
bf2p57 | why does apple use the "i" prefix on their products? (ipod, iphone, ipad etc.) | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/bf2p57/eli5_why_does_apple_use_the_i_prefix_on_their/ | {
"a_id": [
"elae9xm",
"elaen8y"
],
"score": [
13,
3
],
"text": [
"The i- prefix was created as part of the iMac in the late 90s and was adopted into a full product line shortly after.\n\nThe original meaning was \"internet\", meaning the iMac was capable of internet connectivity out of the box, but Apple and Jobs used it more to refer to \"individuality\" and \"innovation\".\n\nBut the long and short of the matter is that i- became a handy and easy to remember code for \"Apple\", and they marketed the hell out of it.",
"The lowercase i is a smart branding move to tie together a variety of products under the Apple label. The i suggests “intelligence”, especially during the time when the difference between a regular phone and an iphone was significant.\n\nThis trait is also reminiscent of a lot of early web (90s) branding, when everything was ‘eBay’, ‘eToys’, and ‘_URL_0_’."
]
} | [] | [] | [
[],
[
"Pets.com"
]
] |
||
346pee | why aren't laptop plugs grounded anymore? | My impression has always been that sending electronics tend to need grounded plugs to stay safe and protected, while things like lamps and clocks didn't need this... But modern laptops are often (if not always) ungrounded. Is this a technological change, or did I misinterpret the purpose of grounding in the first place? | explainlikeimfive | http://www.reddit.com/r/explainlikeimfive/comments/346pee/eli5_why_arent_laptop_plugs_grounded_anymore/ | {
"a_id": [
"cqrr1ej"
],
"score": [
5
],
"text": [
"They're all double insulated now. Even if there's a short, you won't be exposed to a dangerous voltage so there's no need to have the ground prong."
]
} | [] | [] | [
[]
] |
|
5b7ylt | what is "mental exhaustion"? | How is it that I can get home from a day of work that was not physically strenuous but was full of the stress of complex scheduling, planning, and time-sensitive execution of plans and feel completely drained? | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/5b7ylt/eli5_what_is_mental_exhaustion/ | {
"a_id": [
"d9mgrla",
"d9mhpb6",
"d9n1ji2"
],
"score": [
34,
14,
3
],
"text": [
"Your brain in a resting state will burn around 20% of calories even though it's less then 5% of your bodyweight. Actively using your brain literally burns more calories, and I think something like repeat firing of pathways leads to decreased neurotransmitter response over time and so you feel burnt out",
"i think it's mostly the stress; in the unlikely event i go through a productive day at work with minimal stress (supported by being in good shape, getting a good nights sleep, eating well, going for a couple of walks during the work day, stretching, not listening to or reading the news or going on social media sites during or before work, meditating before work, feeling good about myself and the world, taking deep breaths throughout the day, being kind and gentle with myself throughout the day, not taking things personally, feeling gratitude for good things in my life), i find i'm still energized when i get home. It's really when i'm not taking good care of myself in the ways listed above that i feel drained. and stressed. ",
"When you use your brain, it gets tired faster. \nWhen you use your body, it gets tired faster. \n\nIf you use your **brain** a lot more than your body, you have **mental exhaustion** when your body is perfectly fine to keep moving.\n\nIf you use your **body** a lot more than your brain, you have **physical exhaustion** when your brain is perfectly fine to keep thinking.\n\nThe actual process is pretty **complicated** if you go deeper. You have ATP exhaustion (literally running out of energy, it's very temporary), stress hormones, actual damage to your muscles, forming new memories, willpower running out (still very theoretical), and so forth.\n\nBut generally speaking, you can overcome brain exhaustion if you like what you're doing, are having fun, and drain yourself often with difficult tasks. This makes the analogy to worn out muscles very useful."
]
} | [] | [] | [
[],
[],
[]
] |
|
5s7owl | when surgeons remove a part of the brain, how do they fill the hole left behind? | So I was watching a documentary about a girl who had half her brain removed and I realised they can't just leave the gaping hole there. | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/5s7owl/eli5_when_surgeons_remove_a_part_of_the_brain_how/ | {
"a_id": [
"ddd0i80",
"dddjz1t"
],
"score": [
23,
3
],
"text": [
"The brain is suspended in a layer of fluid, called cerebrospinal fluid (or CSF). If parts of the brain are removed, the \"gaps\" get filled with CSF. ",
"Usually when removing tissue from anywhere in the body they are doing it to relieve excess pressure. Filling the hole with anything would be counter productive, and provide a vector for infection to take place."
]
} | [] | [] | [
[],
[]
] |
|
8sxux3 | what led to world war ii? could the war have been prevented? | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/8sxux3/eli5_what_led_to_world_war_ii_could_the_war_have/ | {
"a_id": [
"e135vg1",
"e135z75",
"e1360dt",
"e1366zl"
],
"score": [
2,
2,
3,
2
],
"text": [
"The sanctions put against Germany after ww1 cause such disparity and debt that the whole country was in turnmoil. This allowed Hitler to take power because he was a radical and when your desperate you will be more likely to listen to the radical, country loving charismatic man. Hitler managed to piss off a lot of people by annexing land.\n\nThen essentially we pissed off the japanese who were allied with Hitler. USA got pissed after pear harbor. \n\nThen Ben Affleck and his best friend Josh Hartnett saved us all.",
"After WWI ended, the allies made Germany sign an abusive set of concessions called the Treaty of Versailles. This left the country in such a shitty situation that they felt like the only possible solution they came up with was to vote for WWI veteran Adolf Hitler. Should the winners of WWI have had more mercy on Germany, perhaps WWII could have been avoided. ",
" > What led to World War II?\n\nWorld War 1. Specifically the harsh terms that Germany was hit with by the Armistice\n\n > Could the war have been prevented?\n\nCertainly, by not being dicks to Germany when they didn't even lose WWI. This is why the Allies put tons of resources into rebuilding Japan and Germany after the war. If you blow up a country and leave unemployed people to pick through the rubble then they're grumpy and will make trouble for you. If you employ them to build up industry and infrastructure in their country then they're happier and have less free time for rebellious thoughts",
"Hitler's warmongering led to WWII. You could go into detail about what that warmongering consisted of, but it's all just variations on a theme.\n\nThere's a lot of talk about *WWII could have been prevented, if only...* but those hypotheticals are almost always about *if only Britain or France or somebody had reacted more vigorously when Germany reoccupied the Rhineland/annexed Austria/took over Czechoslovakia.* And those scenarios seldom really end with the war prevented: they'd just start it earlier, and maybe (or maybe not) end it faster."
]
} | [] | [] | [
[],
[],
[],
[]
] |
||
aa7l7n | how does a relatively small transformer fire light up almost an entire city? also, why is it blue? | [deleted] | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/aa7l7n/eli5_how_does_a_relatively_small_transformer_fire/ | {
"a_id": [
"ecpod3u",
"ecqhdd6",
"ecqq4j3"
],
"score": [
180,
5,
2
],
"text": [
"Even a relatively small transformer draws a massive amount of power. The power supply is high voltage AC, which is arcing in the open air. Basically, the open air is acting as a fluorescent bulb. It's mostly light from nitrogen, which glows blue, like neon glows red.\n\nIt's not an unusual thing to have happen, but I've never seen it to quite this extent before.",
"The small transformer is connected to a bigger transformer at the nearest substation. This much bigger transformer is feeding the short-circuit. \n\nYou don't get the same energy from a short circuit on your outlet, for example.\n\n",
"The color light is measured in something called color temperature. It's referenced in degrees Kelvin. The scale is based on what colored light tungsten outputs when heated to different temperatures. The lower the temperature the more orange or red the light, the higher the temperature the bluer it is.\n\nWarm white light bulbs in your house are going to be somewhere in the 3000 range, the sun is more like 7200. Arc welding, which is basically what this was, is way high on that chart, therefore the light looks blue.\n\n_URL_0_"
]
} | [] | [] | [
[],
[],
[
"https://goo.gl/images/psJjbc"
]
] |
|
1h3tnv | why restaurants have policies to throw out food at the end of the day instead of donating/eating it? | explainlikeimfive | http://www.reddit.com/r/explainlikeimfive/comments/1h3tnv/eli5_why_restaurants_have_policies_to_throw_out/ | {
"a_id": [
"caqk79q",
"caql29e",
"caqlhhl",
"caqliy3",
"caqmx7l",
"caqogz3"
],
"score": [
57,
6,
3,
16,
3,
5
],
"text": [
"A policy of allowing staff to eat the food tends to encourage staff to \"accidentally\" prepare more food than what's actually required.\n\nA policy of donating food causes issues of liability if someone should suffer from food poisoning from food they haven't paid for, that may not be eaten immediately and may have passed its \"sell by\" time before it gets eaten.",
"In some places, health code laws demand that even free food be stored and served at appropriate temperatures. Food service places must keep hot food hot and cold food cold to prevent bacteria takeover. ",
"Where I work, we are happy to donate our leftover food, but for us at least, the responsibility lies with the place we are donating them to. It's up to them to pick up the food, but sometimes they are very inconsistent in when they pick it up, and we don't like having days old food now taking up space in our store.",
"My brother used to be night manager of a pizza delivery place.\n\nThey used to give away mistake pizzas at the end of the night. Most the people weren't needy, they were just kids looking for a freebie, kids who got fed at home and could pay for a pizza if they had to. He also noticed there would be a lot of undeliverable pizzas called in during the last hour or so.\n\nSo he started throwing the pizzas out, and the bad calls went way down.",
"i'd add that some places throw out food instead of donating because they don't want to foster dependency.\n\na friend of mine used to run a sub shop and at the end of the night he noticed a few homeless guys regularly swung by. at first he gave them whatever was left over but over time they got used to it and he felt bad when he didn't have any left-overs. that and psychological issues with the homeless guys did not make for a great combination.\n\nnot saying it's common but it does happen.",
"1: If you give food to a homeless, they will come back every night expecting food. They may also bring friends. If you have no food, They may vandalise your property as revenge, or start sifting through your bins. When they go through bins they are rarely careful and spread rubbish all over the place. The next day, my business gets blamed. Now I have to invest in lockable bins.\n\n2: If you give the food to staff, like the homeless, they will come to expect it and you then appear to be a tyrant when costs go up, and you are tightening the belt. Also they will put through 'Bad' orders knowing that they will be able to eat it later - If this is purposefully making a customers order wrong this will affect your service as the customers food will need to be re-made.\n\nWe always hear the argument 'It's going in the bin, so it should go in my belly to make it cost effective' - Doesn't bother me where the food goes, as I have already paid for the initial food cost of the food. The only cost to me is the lost revenue the food COULD have gotten me if sold at full price.\n\nUltimately people are assholes. especially in a minimum wage job - If you give them an inch, they will take a mile. Sure, they may be respectful for a little while and genuinely only take the actual bad orders - But it ALWAYS ends up as described above - So it is easier to have a blanket ban on eating mismade food than to micromanage.\nAs a business, however, the idea should always be to have 'Minimum stock' on the shelves - So we only buy as much food as we are going to cook, use the oldest stuff first and monitor wastage and use really carefully. So much so that part of the managers bonus is based on their food cost. So having any food that is available to be given away is a bad thing.\n\nThere may also be legal issues - If someone gets ill from the food, who is liable? Normally it will be the resturant - so it's good practise to only give out food that people have bought in good faith and you know to be cooked and stored correctly."
]
} | [] | [] | [
[],
[],
[],
[],
[],
[]
] |
||
5pxbgj | when muscles get stronger they grow. how do our lungs get stronger if you go for a long run? | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/5pxbgj/eli5_when_muscles_get_stronger_they_grow_how_do/ | {
"a_id": [
"dcuj9ur",
"dcujctw",
"dcusotu"
],
"score": [
3,
9,
2
],
"text": [
"They don't particularly get stronger. You just increase the efficiency of your body. So much so that you can better process's oxygen. When you get fitter, your heart doesn't need to work as hard to pump blood around your body, so that is more efficient. Your muscles get stronger so exercise gets easier, which in turn makes breathing easier as you don't need as much oxygen. \n\nHave a look at VO2Max. It's the efficiency of your heart/lungs. ",
"Your lungs aren't actually a muscle. They themselves can't get stronger, because they're not the thing providing the power to breathe.\n\nYou breathe with a muscle called your *diaphragm*. It's a sheet of muscle that separates your chest from your belly. When it contracts, it moves downwards. This increases the pressure in your belly and decreases the pressure in your chest. As the pressure in your chest decreases, air rushes in from your nose/mouth and inflates your lungs, like two little balloons. To breathe out, the diaphragm relaxes, moving back upwards. This increases the pressure in your chest again, squeezing the air out of your lungs back up your windpipe and out your mouth/nose. Your lungs never actually do any work; they only ever \"get inflated\" and \"get deflated\".\n\nWhen you go for a long run, you're strengthening your diaphragm.",
"It's actually the efficiency with which the skeletal muscles(responsible for running) utilise oxygen that changes with running everyday. In marathon runners and those who run long distances, the red muscle fibres develop that utilise a lot of oxygen without getting fatigued. The oxygen carrying pigment in muscles myoglobin increases there.\nIn sprint runners, the white muscle fibres that provide a boost of energy (via anaerobic mechanisms) develop with that training they do. \nLungs are doing almost the same thing in both cases, it's the body that copes more."
]
} | [] | [] | [
[],
[],
[]
] |
||
4tv56o | what is the issue with combating illegal immigration from mexico? | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/4tv56o/eli5_what_is_the_issue_with_combating_illegal/ | {
"a_id": [
"d5kl5x3",
"d5kl8gn",
"d5klmzi",
"d5kmqf7"
],
"score": [
4,
2,
6,
2
],
"text": [
"The actual cost of trying to limit crossing is extremely expensive and may lower the net amount coming in, but that's speculation. A far more effective way would be immigration reform and stronger regulations on employers. Illegal immigration occurs due to employment. These people leave their countries due to lack of opportunity. Trying to secure a border is very surface level. If regulations made it difficult for illegal immigrants to get employment then there'd be less of them coming in without spending as much physically patrolling these areas.",
"You should try to look at the actual numbers involved before determining if anything should be done. If illegal immigrants accounted for 1% of immigration and took 0.1% of new jobs, I think its safe to say that the issue is minor and not worth worrying about. However if 50% of immigrants were illegal and took 10% of new jobs, it would be a serious issue, especially with job shortages already. I personally think people use racism to make it out to be a bigger issue then it actually is, but I havn't looked into the numbers so I can't say that with certainty. ",
"There is a fallacy called the lump of labour:\n\n_URL_0_\n\nWhich means that people mistakenly think that employment is a zero-sum game, that is, there's only a fixed amount of jobs to go around and that if one person gets a job, it must mean someone else doesn't get a job (which is false). Immigrants pay taxes (even illegal ones via sales tax), pay rent, and buy things with the income they earn. This in turn gives employment and business opportunities to people who want to sell things and lease out property to these immigrants.\n\nAnyways, building a wall is an expensive task and a colossal waste of taxpayer dollars, and also won't keep businesses from giving jobs to Mexicans. If Mexicans can't come here, businesses will simply close factories in the US and open up factories in Mexico. If we establish laws against doing that, those businesses will simply leave the US and move their headquarters to countries with fewer regulations. We live in a global economy now, and we need to learn how to compete and provide goods efficiently and at a low cost.",
"it's more to do with how you accomplish that. the financial cost of patrolling, surveying, or otherwise actively defending the border is quite obvious and I won't do more than say it's several thousand miles of mostly harsh desert. \n\nthe issue comes down to 1 key question, how far are we willing to go to stop them?\n\nto use an extreme example, it would be insane to plant minefields along the border. *even if* it solved the problem, most people will recognize that blasting someone to ribbons isn't an appropriate response to the transgression. We don't chop thieves' hands off, we don't (well, shouldn't) use torture *at all,* and we don't kill people for non-violent offenses. by maintaining these standards, we are implicitly permissive of a certain degree of criminality. \n\n(and before anyone goes questioning efficacy, the point is the principle, not the practical)\n\nwhere that line falls is complicated. how much harm is done by this permissiveness? how willing are you to tell the shop owner you aren't willing to protect his livelihood because you won't do what it takes to stop the offender? how well can you sleep knowing your border defenses cause people to die, frozen and starving in a wasteland trying to improve their lives? it's a heavy issue. \n\nfor the curious, last I checked it was around 500 people annually. "
]
} | [] | [] | [
[],
[],
[
"https://en.wikipedia.org/wiki/Lump_of_labour_fallacy"
],
[]
] |
||
331v15 | why do plastic/office/work and school chairs have a hole or nothing right where your ass crack is. | It always used to make me self conscious in school, and I always just saw it as fuel to bully people | explainlikeimfive | http://www.reddit.com/r/explainlikeimfive/comments/331v15/eli5why_do_plasticofficework_and_school_chairs/ | {
"a_id": [
"cqgpgs5",
"cqgq1o0"
],
"score": [
3,
2
],
"text": [
"At my high school it was so boys could drop pencils down girls' butt cracks. ",
"It's cheaper to make, less likely to deform during the molding process, and gives you an easy way to pick up the chair. "
]
} | [] | [] | [
[],
[]
] |
|
8tloy0 | why do aerosol cans explode/catch fire when exposed to heat? | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/8tloy0/eli5_why_do_aerosol_cans_explodecatch_fire_when/ | {
"a_id": [
"e18fn26"
],
"score": [
3
],
"text": [
"Heat makes the contents expand, aerosol cans already are pressurised by design so it doesn't take massive amounts of expansion for it to become too much, then kaboom!"
]
} | [] | [] | [
[]
] |
||
29gmfs | why do doctors say to take antibiotics and wait (x) amount of time between the antibiotics and eating food | explainlikeimfive | http://www.reddit.com/r/explainlikeimfive/comments/29gmfs/eli5why_do_doctors_say_to_take_antibiotics_and/ | {
"a_id": [
"cikq42l"
],
"score": [
2
],
"text": [
"Antibiotics are typically absorbed better on an empty stomach. Some of them, especially penicillin and amoxicillin, are best absorbed when taken with a full glass of water."
]
} | [] | [] | [
[]
] |
||
3xd8ol | why is mother teresa so revered? | She's one of the most iconic people of the last 100 years.
What did she do that made her stand out? There's been plenty of nuns before her. I get that she devoted her life to helping people in need, but was there something more she did to get her iconic status? | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/3xd8ol/eli5_why_is_mother_teresa_so_revered/ | {
"a_id": [
"cy3o9wn",
"cy3r1ad"
],
"score": [
16,
6
],
"text": [
"Because she got big.\n\nDevoting your life to helping others is big. \n\nFounding an organization that inspires many people to devote their lives to helping others is bigger. And if you get big enough to make the church look good, you get to be a saint.\n\nAlso, be aware there is a lot of controversy over the degree to which she actually helped others. She wasn't terribly interested in making the poor less poor or the sick less sick, or to help anyone suffer less. Her mission was to make sure the poor and sick, and suffering were converted to her religion, and saw suffering as a form of religious cleansing. Her order raised lots of money, but reached relatively few people, and that for missionary work, not charity work.",
"Often because people do not do their research. While she's often used as an example for the moral high ground, she did many terrible things with her influence.\n\nNot only did she spend others' money to convert the poor to her religion (mostly instead of helping them, though she did help some), she tried to convert them to a religion that she did not believe. There are several letters in which she confesses this, to the point that, near her death, she was always surrounded by theologians to combat her doubt.\n\nAnother example (near the top of /r/atheism right now, so it's not exactly unbiased) is when she was informed that *large* donations made to her were stolen money and never returned it, or *even replied*."
]
} | [] | [] | [
[],
[]
] |
|
3cev7r | what is happening when you shake a can of spray paint? | Similarly with other various cans and markers. | explainlikeimfive | http://www.reddit.com/r/explainlikeimfive/comments/3cev7r/eli5_what_is_happening_when_you_shake_a_can_of/ | {
"a_id": [
"csuuczi"
],
"score": [
4
],
"text": [
"The paint has been sitting and has separated, i.e. become unmixed. There is a marble inside the can. When you shake it, the marble helps mix up the paint."
]
} | [] | [] | [
[]
] |
|
10gfen | what do ferrite beads do? how do they work? | I tried reading the wiki article on [ferrite beads](_URL_0_) but I don't have a strong background the physics and terminology of electricity. | explainlikeimfive | http://www.reddit.com/r/explainlikeimfive/comments/10gfen/what_do_ferrite_beads_do_how_do_they_work/ | {
"a_id": [
"c6d98xo",
"c6d9nwp"
],
"score": [
5,
4
],
"text": [
"Ever been listening to a radio station and been annoyed by all of the static in the background? Well, power supplies can have \"static\" as well, in the form of high frequency power disruptions. Ferrite beads act as a filter to eliminate those high frequency disruptions. The energy from them is dissipated as heat.\n\nHaving a cleaner power signal can help sensitive electronics work most optimally, and even prevent them from being damaged.",
"The key idea is that electric fields and magnetic fields are related to each other, and if you find one you often find the other. (An aside: These were some of the greatest scientific discoveries of the 19th century. [James Clerk Maxwell](_URL_0_) is the guy who put it all together, although other people before him came up with most of the pieces.)\n \nA moving electrical charge will induce a magnetic field, which becomes concentrated by the ferrite bead. If the current fluctuates, changes in the magnetic field will in turn tend to create an electric field, and that field will oppose the electrical current that created the magnetic field in the first place. (You might need to read that last sentence a couple of times.) \n \nStated more simply, the ferrite bead doesn't like change. So the ferrite bead acts as a kind of filter, absorbing certain frequencies. The frequencies it absorbs are going to depend on the exact size, shape, material, etc. \n \nThe ferrite bead on a typical power supply line input is designed to absorb high frequency \"noise\" that is much higher than the 50 or 60 Hz electricity coming from the power mains (usually in the MHz range, if I remember correctly). This prevents things like a PC power supply from putting noise back into the house, and prevents noise from the house from propagating into the PC's power supply (and then into the circuit). \n \nThey generally won't help much with big power fluctuations or surges, since they are designed for higher frequencies and can only absorb fairly limited amounts of power. \n \nThey are valuable because some of the parts of a computer, like the CPU, don't particularly appreciate voltage fluctuations. Because they operate very, very fast, they are most sensitive to very fast changes in the power supply. And because they operate so fast, they *create* very rapid fluctuations in the power supply themselves! (In that way, they are their own worst enemy.) \n \nTL;DR - What do they do? Protect stuff from high frequency noise. How? Magnets. "
]
} | [] | [
"http://en.wikipedia.org/wiki/Ferrite_bead"
] | [
[],
[
"http://en.wikipedia.org/wiki/James_Clerk_Maxwell"
]
] |
|
1440ws | why do 2gb torrents of movies look better than the. 4.7/9.4(dl) dvd? | I know torrents generally use h.264 or another format that is more efficient than DVDs (MPEG2 I think), but why would DVDs use a format that is so much less efficient? | explainlikeimfive | http://www.reddit.com/r/explainlikeimfive/comments/1440ws/eli5why_do_2gb_torrents_of_movies_look_better/ | {
"a_id": [
"c79ocel",
"c79odcv",
"c79p1sn"
],
"score": [
5,
5,
3
],
"text": [
"Because DVD's are made to play in consumer electronics devices that don't change over time. In order to maintain consumer confidence and interoperability, every DVD and every DVD player has to be built to the same standard so that every DVD can play in every player, and vice versa. I have a DVD player from 2002 that I still use, and it plays even the newest discs (theoretically). \n\nComputers don't have this problem, because the files are stored in a digital format that isn't dependent on standards. If you were to try to use, for example, a computer from 2002 to play a Blu-Ray disc it wouldn't work because Windows XP (pre-SP2) doesn't support HDCP et al. \n\nThe reason is basically that I can upgrade my computer and use newer, more efficient codecs, but I can't upgrade my DVD player (not because it's impossible, but because it wasn't designed that way). \n\nDVD's were upgraded to newer codecs - but doing so requires establishing a new standard - hence the existence of Blu Rays. \n\n",
"Decompressing a video takes computer power. We don't want to put a computer in every DVD player. That's expensive. ",
"2 GB torrents have probably been created from a 720p/1080p source. DVDs have a 720 x 576 maximum native resolution. Torrents based on DVDs were typically around 700 MB for a feature length movie."
]
} | [] | [] | [
[],
[],
[]
] |
|
3ah7c6 | why do some tv commercials get shorter overtime? | explainlikeimfive | http://www.reddit.com/r/explainlikeimfive/comments/3ah7c6/eli5_why_do_some_tv_commercials_get_shorter/ | {
"a_id": [
"csclzlp",
"cscms2k"
],
"score": [
15,
2
],
"text": [
"Because now that it's already ingrained in your head, they just need to remind you, not explain it again.",
"Because it costs a lot of money to have long ads on a TV channel. After a while, companies decide to invest less money on a certain ad by making it shorter since the ad already brought most of the potential new customers and they only need a \"reminder\" that the product exists."
]
} | [] | [] | [
[],
[]
] |
||
ytstv | how does an individual count bars of music? | essentially i'm trying to fully understand how music works on a bar & hook level. the generic formula is: (16 bars and a hook)*3 = popular song, at least in the radio rap world.
can someone explain it to me so that i can listen to any song and count the bars, identify where they begin and end and break down how long the hook is? | explainlikeimfive | http://www.reddit.com/r/explainlikeimfive/comments/ytstv/eli5_how_does_an_individual_count_bars_of_music/ | {
"a_id": [
"c5ys76l"
],
"score": [
2
],
"text": [
" Standard songs have 3 sections: A,B and C. \nA is the verse (where the \"story\" of the song happens), \nB is the chorus (where the \"hook\" happens),\n C is the bridge ( where something totally different happens, like a key change or breakdown). \nTypical songs are ABABCB. \nEach bar is 4 beats (in 4/4). Count how many times you count to 4 in a section, and that's how many bars it is. An 8 bar section has 32 beats in (4/4). "
]
} | [] | [] | [
[]
] |
|
5egqaq | freud's theory of religion as an illusion. | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/5egqaq/eli5freuds_theory_of_religion_as_an_illusion/ | {
"a_id": [
"dacaaif"
],
"score": [
3
],
"text": [
"Basically by having a mythology which has a superior illusionary being at the top it doesn't require the population to think about the mysteries of life because they can put it all down to god did it. No need for education of the masses other than in god where there is no need to attempt to prove that a god exists because they have faith in the illusion. With the belief in place the population are easy to control to follow god's message and rules etc."
]
} | [] | [] | [
[]
] |
||
1o6ilb | if glass stops uv radiation, why can i still feel the heat of the suns rays? can i still get a tan? | I had been told (by a pseudo-reliable source) that you can't get sunburn through glass because it filters out UV radiation. If that's true how can you still feel the heat of the suns rays through glass, and would you still get a tan/sunburn from them. | explainlikeimfive | http://www.reddit.com/r/explainlikeimfive/comments/1o6ilb/eli5_if_glass_stops_uv_radiation_why_can_i_still/ | {
"a_id": [
"ccp7k25",
"ccp8xd1",
"ccpak6n",
"ccpcvqa"
],
"score": [
5,
3,
2,
3
],
"text": [
"UV and Thermal radiation are two different things. And yes it is possible to get tans and burns through glass, only UV filtered glass will filter the UV radiation, and even then long enough exposure through said glass theoretically could create a tan or burn, due to the fact it rarely filters 100% of the radiation. Where as thermal radiation isn't generally going to be absorbed by the glass, so the wavelengths which fall under thermal radiation are passed through. ",
"UV radiation is not the only type given off by the sun. I'm sure you're aware it gives off visible light too.\n\nHeat, however, is infrared radiation, which is quite capable of travelling through glass, while infrared is blocked.",
"A little UV radiation is filtered out, but not much--only about 2%. Ditto for visible light. If you lie on the living room floor all afternoon you'll still get sunburn.",
"Straight up glass lets a lot of UVA through. Glass for houses and automobiles often comes with coatings that block UV almost completely, and there are also (rare, expensive) kinds of \"glass\" that are completely transparent to UV such as good old fuzed quartz.\n\nHowever, there's something else going on here. Most of the [sun's energy](_URL_0_) is carried in the visible part of the [spectrum](_URL_1_). You're not feeling UV or infrared much. The heat of sunlight is mostly energy carried by light you can see.\n\nUV causes sunburns because it is energetic enough to shred DNA. Infrared is much lower energy and many glasses have coatings that block it to help keep your house from cooling off.\n\n"
]
} | [] | [] | [
[],
[],
[],
[
"http://upload.wikimedia.org/wikipedia/commons/4/4c/Solar_Spectrum.png",
"http://www.yorku.ca/eye/spectru.htm"
]
] |
|
1ou858 | thermal paste, how does it work? | explainlikeimfive | http://www.reddit.com/r/explainlikeimfive/comments/1ou858/eli5_thermal_paste_how_does_it_work/ | {
"a_id": [
"ccvn7g1"
],
"score": [
3
],
"text": [
"It's basically a grease designed specifically to transmit heat well (for example between a chip and the heat sinks so heat moves away). You need the grease because it will tend to fill or absorb any air pockets due to imperfections in the surface of the chip or the base of the heat sink. Air is a good thermal insulator so you definitely don't want it in the middle there."
]
} | [] | [] | [
[]
] |
||
5jkeeg | did "free market" economy develop out of human behaviour and nature, or was it institutionalized after the theory of adam smith (like communism and karl marx)? | Hey people,
one thing has been bugging my mind recently:
The whole western world has the free market as its basic economic system. When it all started, was it institutionalized after the theory of Adam Smith (and others), or did it just "happen" following basic principles of human behaviour?
The analogy I drew was communism, which finds its roots in books written by philosophers like Karl Marx or Friedrich Engels. Does this analogy apply to the free market too?
Thanks!! | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/5jkeeg/eli5_did_free_market_economy_develop_out_of_human/ | {
"a_id": [
"dbgsrsn"
],
"score": [
3
],
"text": [
"Adam Smith was not a founder, progenitor, or even staunch advocate of the free market or capitalism. Rather, he was simply a Scottish professor who wrote on a variety of economic, philosophical, and morality issues --- one of which was the free-market system (as opposed to the general European model of the day in which the government had a very active role in the economy, generally through granting licenses and rents to preferred individuals or companies). However, his work was glommed onto in later years (especially in the 19th century) by advocates of less governmental control of business activity. \nIn several of his writings, Smith discussed the ability of an unfettered market to best allocate resources. But he also warned of the problems of wealth accumulation that this would cause, and was a proponent of government smoothing the extreme limits of capitalism. \nMarxism was a little different, in that the early Communists were heavily influenced by Marx's writings and sought to create a state in Russia modeled on his ideas. Also, Marxism essentially models a type of government, whereas capitalism has little to do with government. So comparing the two is a bit of a fallacy --- like comparing basketball (a sport) to FIFA (an organization that regulates and governs a sport)."
]
} | [] | [] | [
[]
] |
|
2dczgt | does all the money in the world really exist physically? if you added up all the bank accounts, would there be physical money to equal that? | explainlikeimfive | http://www.reddit.com/r/explainlikeimfive/comments/2dczgt/eli5_does_all_the_money_in_the_world_really_exist/ | {
"a_id": [
"cjob996",
"cjobh13",
"cjodfz5",
"cjodm0i",
"cjoepuk",
"cjof3li",
"cjorxhv"
],
"score": [
8,
3,
81,
8,
2,
2,
2
],
"text": [
"No, only a fraction of the world's wealth physically exists. Most of it is just data. ",
"No. same with gold and other precious commodities. Never buy a gold certificate stating you 'have' gold... ",
"Not only does the money not physically exist, there is no means to tell exactly how much money DOES exist at any given time. \nLet me give you an example. \n\nYou have $10,000. \nYou put that $10,000 in the bank. You still have $10,000.\nThe bank (being a bank) lends $9000 of that money out to a company. \nYou still have $10,000, but the company now has $9000, too. \nThe company uses that $9000 to pay nine of its workers. Each of those workers takes home $1000. \nYou still have that $10,000, and each of those workers has $1,000.\nOne worker puts that money into the bank. And the loop starts all over again. \nMoney is imaginary. ",
"I agree with the \"no\" from the other posters, but here's a little more detail as I understand it. The key to why there is more \"money\" than there is physical money is a concept known as fractional reserve banking.\n\nSuppose a bank opens. The first customer to walk in deposits $500 cash. \n-Total cash in the bank: $500. Total money in the system: $500.\n\nA few days go by, and the customer doesn't return for his money. A second customer walks up and requests a $50 loan. The bank rationalizes that the first customer is unlikely to take all his money out at once, and loans that $50 to the second customer.\n-Total cash in the bank: $450 Total money in the system: $500 original deposit + $50 loan = $550 Fifty dollars was just \"created\" by the bank by lending money!\n\nEventually interest is paid on the loan, others deposit money, take loans, etc. The system expands, but overall there is always more (normally MUCH MORE) money in the system than there is currency.",
"Not by a long shot. Most of it is the idea of value. For example, I live in a house. let's say it's worth a hundred thousand dollars. I didn't give anyone a hundred thousand dollars in cash to get it, I just gave them a few thousand and then I pay them every month (I have mine auto deducted, so I pay in data). That money doesn't exist. \n\nMore importantly, that money doesn't *need* to exist. The paper is worth nothing. The only reason it had value is because it represents something I did or had. I gave you a car and you gave me paper representing what you think the car is worth. I worked many hours and my boss gave me paper that represented the value I put into the economy (and probably that isn't paper either). ",
"If there was a crisis and lots of people went to the bank to withdraw their money it would not work. Right? ",
"Of course not. "
]
} | [] | [] | [
[],
[],
[],
[],
[],
[],
[]
] |
||
3jnoms | if obesity is one of the most serious health issues that our societies are facing, then why aren't the governments restricting or forbidding access to products that are high in calories but offer little nutritional value, such as alcohol and foods rich in added sugar? | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/3jnoms/eli5if_obesity_is_one_of_the_most_serious_health/ | {
"a_id": [
"cuqs5dl",
"cuqs5k6",
"cuqs74m"
],
"score": [
4,
2,
2
],
"text": [
"Because personal liberty. It's not the government's role to protect me from myself. That's on me.",
"Because people have the freedom to be unhealthy if they want to. I mean, if the government were to start making unhealthy things illegal, it's only a small step toward making illegal to *not* go to the gym.",
"Because people in excellent shape also enjoy booze and candy and donuts once in a while. It is not the government's responsibility to be our fucking mommy. \n\nIf someone wants to do damage to themselves, they will. Making it harder won't change what they want. \n"
]
} | [] | [] | [
[],
[],
[]
] |
||
5vz24g | how are we able to come up with responses to questions so quickly without thinking about what we are going to say in conversation? | As in: "wow he's having a lot of fun" "yeah he looks really happy"
Especially in the case when we are defending someone/something:
"Stop staring at her!" "I was just looking!"
"He spilled it all over the table!" "I didn't, I found it like that!" etc | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/5vz24g/eli5_how_are_we_able_to_come_up_with_responses_to/ | {
"a_id": [
"de6ic18"
],
"score": [
2
],
"text": [
"Because your brain is much much faster than your mouth. It might not feel like your brain is lining the words up and then waiting for your mouth to say them, but it kinda is."
]
} | [] | [] | [
[]
] |
|
59etmv | why can't our hands be 100% steady still? | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/59etmv/eli5_why_cant_our_hands_be_100_steady_still/ | {
"a_id": [
"d97wysy"
],
"score": [
5
],
"text": [
"Your hands depend on a feedback loop from your nerves to your brain to your muscles. That's never going to win a match with a tripod to hold a camera steady. But, you can learn to ride a unicycle, and a tripod can't do that."
]
} | [] | [] | [
[]
] |
||
4fdx0k | why can't we use heaters/radiators to cool our homes in the summer by running cold instead of hot water through them? | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/4fdx0k/eli5_why_cant_we_use_heatersradiators_to_cool_our/ | {
"a_id": [
"d27zon9",
"d27zoo9",
"d27zud0",
"d283iqv",
"d284exm",
"d284pkk"
],
"score": [
8,
7,
3,
2,
2,
2
],
"text": [
"It can be done. I lived in such a building. However, water can condense on the cool radiators, making a huge puddle. Thus, forced air (blowing across the cooling pipes with a fan) is usually used.",
"We could, but to make it work the radiators would have to be very very cold, which means they'd either be running with condensation or covered in ice, neither of which is ideal.",
"The radiators would have condensation dripping from them. Each would need a drip pan and drain. It would be a mildewy mess. It's much more efficient to blow air over one cold coil and distribute that air. ",
"That's basically what your typical in-window air conditioner does.\n\nAs others have said, this can lead to condensation on the portion with the cold liquid in it, but AC units are designed to catch that water and funnel it outside (where it usually drips out the back and falls on the neighbors in an apartment style setting)\n\nSome places with central HVAC(Heating, Ventilation and AirConditioning) basically use systems that can be reversed to provide heating and cooling by means of a heat pump, though most will use separate systems for heating and cooling- and in either case warm or cold air is distributed via duct work to the rooms of the building.",
"They absolutely can be. It's called hydronic air conditioning. \n\nThe problem is that unlike floor level heaters, these radiators need to be mounted at ceiling level in order to create enough air convection to effectively cool a room, so it becomes more difficult to use the same heat exchanger for both purposes.\n\nAlso like others have mentioned condensation is an issue so hydronic cooling avoids this by using larger radiators that don't get as cold as they could. The extra size of the radiator increases cooling capacity without having to chill the water so much that condensation becomes a serious problem.",
"As well as condensation, consider this:\n\nHeating is done by water up to around 80°C, which is too hot to touch but doesn't injure after brief contact, and that's 60° warmer than room temp., whereas cooling with water that's near freezing would be a temp. diff. of only 20°, so it would only have 1/3 the effectiveness. Brine would work better but increases rusting etc.\n\nIn addition, radiators distribute heat via 2 methods, convection and infra red radiation. Cooling would only have one of these to work with, convection. So, even less efficient.\n\nAlso, radiators are usually white or silver, to increase the amount of radiating. But heat-absorption would work best with matte black units, so even less efficient.\n\nAaaaaaaaand radiators are placed at floor level so that the heat can rise to the ceiling and then the cooler air takes its place to be heated in turn. But that means you'd want heat *absorbers* to be at ceiling level. Even less efficient."
]
} | [] | [] | [
[],
[],
[],
[],
[],
[]
] |
||
20hq82 | why do some intellectuals not believe in free will? | In Brian Greene's AMA he said [he doesn't believe in free will](_URL_0_), and it blew my mind.
I am wondering if there is some sort of scientific definition for free will that I am not familiar with, that could explain how someone can believe we don't have it.
While I can certainly concede that we each may be more likely to act certain ways at certain times due to hereditary and circumstance it doesn't make evolutionary sense to me why a sentient species *wouldn't* have free will.
**Examples of my understanding:**
> we each may be more likely to act certain ways at certain times due to hereditary and circumstance
* Some criminals inherit brain structure/patterns that make them less capable of empathy/more aggressive/etc..
* If I am overly tired, hungry, and hormonal I am more likely to snap when someone irritates me - almost as if I don't even have control over my irritability.
> it doesn't make evolutionary sense to me why a sentient species *wouldn't* have free will
* We evolved an ability to see patterns and respond to stimuli in order to prolong our life, procreate more, increasing our overall fitness as a species.
* If you see something that seems dangerous, you can choose to ignore the danger (and receive a Darwin award) or respond in an appropriate manner to the danger, live longer, and pass on your genes.
I just don't get it. Isn't the ability to reason, and respond to our environment the entire point of sentience? We are cognitively capable of reacting to our environment - if we didn't need to be able to decide, why have cognisance all?
Sorry, this has really been bothering me since the AMA, and I can't wrap my mind around it. | explainlikeimfive | http://www.reddit.com/r/explainlikeimfive/comments/20hq82/eli5_why_do_some_intellectuals_not_believe_in/ | {
"a_id": [
"cg3c0fu",
"cg3cqf0",
"cg767aw"
],
"score": [
2,
4,
2
],
"text": [
"But your specific thoughts about a situation lead you to an inevitable result based on your personality, and there is only one action you will make because of this.\n\nA thought experiment I did that led me to believe there is no free will is this. The Many Worlds theory of quantum mechanics posits that there are a nearly infinite number of worlds, many many of them completely identical to ours. So let's imagine, say, 100 worlds that are 100% identical to ours. You exist in all of them. You had the same childhood, same experiences, same thoughts at the same time. Now something happens that you react to -- say, a shirt you had been looking at but it was too expensive goes on sale. It's still pricey but more affordable. Do you buy it? Let's look at the first of these 100 worlds -- either you buy it or you don't, but your decision is based on such factors as how much money you have at that moment, your thought processes of how much you want the shirt vs how much it costs, your job situation, and so on. But eventually your thoughts lead you to a decision to either buy it or not.\n\nNow, let's look at world #2. Does the you in that world buy it or not? Same amount of money in his pocket, same job situation, same logical process in his thoughts. It is inevitable that with the same inputs, same brain structure, same experiences that led him to this moment, his decision will be the same. Ditto world #3, 4, etc. Who you are mentally means that you can only do what you would do; the alternative is that everything is random, which is even scarier -- if all my decisions are random and pointless, then that kind of invalidates any sense of identity or purpose.\n\nOur mind, experiences, thoughts, feelings -- all the things that make us, \"us\" -- they make it so that in any circumstance there is only one way we end up behaving. That is not necessarily predictable from either an inner or outer perspective, however. There is a difference between lacking free will and predictability.",
"There's a really good summary of one of the arguments in Orson Scott Card's *Xenocide*. \n\nIf you think of any action as the result of innate human nature like instinct combined with that person's specific history, there is only one possible decision they will ever make to any given situation. Therefore we have no free will. However, the processes behind decision making are so innumerable and complex we can never know how any one person will make a decision in any one situation, therefore while there is no free will for the purposes of society we must act as if there is free will. For if there is no free will then no one would be accountable for their actions. ",
"In the case of public intellectuals such as Brian Greene and Sam Harris, I think it's largely a matter of experts speaking outside of their area of expertise. For instance, they give little consideration to [compatibilism](_URL_1_) even though it's the dominant view of [philosophers working in the area](_URL_0_).\n\nThat said, there *are* decent arguments for the claim that we don't have free will. Here's a few that I find reasonably persuasive:\n\nThe first is Peter van Inwagen's consequence argument. Although van Inwagen does believe in free will, free will sceptics often accept something along similar lines. Here's a simplified version:\n\n1. Neither the laws of nature nor the state of the universe before we were born is up to us.\n\n2. If determinism is true, then our actions are entailed by the laws of nature and the state of the universe before we were born.\n\n3. If X is not up to us, then neither is anything entailed by X.\n\n4. Therefore, if determinism is true, our actions are not up to us.\n\nThe second is Galen Strawson's basic argument. Here's a simplified version of it:\n\n1. You do what you do because of the way you are.\n\n2. To be truly responsible for what you do, you must be truly responsible for the way you are.\n\n3. But it's impossible to be truly responsible for the way you are. (One's character is largely due to one's genes and upbringing.)\n\n4. Therefore, it's impossible to be responsible for what you do.\n\nThe third is Derk Pereboom's four-case argument. Here's a simplified version:\n\n1. Imagine someone, Plum, has whatever version of compatibilist free will you find most plausible - the ability to reflect on one's desires, or to respond to reasons, or whatever - with one exception: his character is a result of direct manipulation by neuroscientists. He can still reflect on his desires and respond to reasons and whatnot, but his actually doing so is a result of direct mental manipulation. Surely such a person is not morally responsible.\n\n2. Now imagine Plum is not being directly manipulated by neuroscientists, but that he was programmed at birth to have the same character as in the first case. There's no relevant difference between his responsibility in this case and in the first, so Plum is not morally responsible here either.\n\n3. Now imagine Plum has not been programmed by neuroscientists at all, but was trained as a young child to have the same character as in the previous cases. Plum was too young to have been responsible for this training. There's no relevant difference between his responsibility in this case and in the second, so Plum is not morally responsible here either.\n\n4. Now imagine Plum is an ordinary human being in a deterministic universe. His actions and character are a direct consequence of the laws of nature and the state of the universe. He has no more control over these than he would over early life experiences or the interventions of neuroscientists. There's no relevant difference between his responsibility in this case and in the third, so Plum is not morally responsible here either.\n\nI should reiterate that these are all simplified versions of their respective arguments, so there's a lot of nuance that I'm leaving out."
]
} | [] | [
"http://www.reddit.com/r/IAmA/comments/1zqteb/i_am_brian_greene_theoretical_physicist_cofounder/cfw42gk"
] | [
[],
[],
[
"http://philpapers.org/surveys/results.pl?affil=Philosophy+faculty+or+PhD&areas0=14&areas_max=1&grain=coarse",
"http://plato.stanford.edu/entries/compatibilism/"
]
] |
|
60sppm | in space, given an infintie amount of fuel could something accelerate forever? | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/60sppm/eli5_in_space_given_an_infintie_amount_of_fuel/ | {
"a_id": [
"df962n5"
],
"score": [
3
],
"text": [
"Yes, given infinite fuel a rocket could accelerate forever at a constant rate. Note that this does not imply that the rocket will surpass the speed of light at any point. Velocity is not given by the simple Newtonian equation v=a*t at relativistic speeds, but by the slightly more complicated equation \n\nv = c tanh(aT/c)\n\nwhere c is the speed of light in vacuum, a is the acceleration and T is the objects proper time.\n\nAs you can see, this function will approach c asymptotically without ever reaching it, even though the object is permanently accelerated.\n\n\nPlease also note that relativistic mass is an outdated concept which should be avoided. It is entirely unnecessary. "
]
} | [] | [] | [
[]
] |
||
1g7160 | why drugs have the stigma that they possess today? | Is it purely because of corrupt governments and money? Or is it because of negative social interactions over the years. | explainlikeimfive | http://www.reddit.com/r/explainlikeimfive/comments/1g7160/eli5_why_drugs_have_the_stigma_that_they_possess/ | {
"a_id": [
"cahco6y",
"cahdehy",
"cahivnv",
"cahj48a"
],
"score": [
16,
11,
2,
2
],
"text": [
"Well... it's obvious there have been enormous negative social impacts from drug use. I think it'd be ridiculous to say it's \"purely\" because of corrupt governments or money. Obviously the War on Drugs didn't help their public image, and some-not-quite-as-bad drugs were caught in the \"drugs are terrible\" crossfire, but it just doesn't make sense to discount the actual harmful issues they cause to society (as a general class, including legal drugs).",
"People have become addicted to and have abused drugs for as long as there have been drugs, legal or illegal. The worst of them will devote all their efforts to acquiring those drugs, ignoring their families, their occupation, the law, and even their own well being. When they create an underclass of destitute, criminal, and easily exploited addicts, there is little wonder they take on a negative stigma.",
"It differs greatly from drug to drug. While there are drugs, like heroin, crack, meth, which fail to present a possibly positive impact on society or medicine and are stigmatized for a reason (in my opinion), there are more drugs (MDMA, LSD, THC) which suffer that stigma due to economic, political or other reasons.",
"Because people cannot handle them so easily as anything else. They affect your mentality, and many people cannot handle it right and misuse them and as a result of that people think drugs are bad. Humanity likes to have control over everything, we need to know how does stuff work, what's good and bad, how should we live and do things etc. Drugs can (and often do) destroy those things in some way, and it is up to you to decide how you'll take it."
]
} | [] | [] | [
[],
[],
[],
[]
] |
|
4q1rnz | what is the bends? | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/4q1rnz/eli5_what_is_the_bends/ | {
"a_id": [
"d4pinnu"
],
"score": [
2
],
"text": [
"When you go underwater to a deep level, the increase in pressure forces nitrogen gas into your blood, just like increased pressure can force CO_2 into pop/soda. When you come up too quickly, the drop in pressure decreases the solubility of the nitrogen, and it comes out of solution and forms gas bubbles in the vascular system (similar to opening a shaken carbonated drink). These bubbles can cause what is called an air embolism, which is when air \"blocks\" a blood vessel and prevents the transmission of oxygen. Since gas goes up due to buoyancy, the bubbles go to your brain, and when your brain gets no oxygen you have big problems. If you come up slowly, the nitrogen leaves through your lungs instead of forming bubbles in your blood vessels, and your live to dive another day."
]
} | [] | [] | [
[]
] |
||
3i5qas | why is the shanghai index plummeting right now? | the index is down, yet there doesn't seem to be a fundamental cause. The news don't go into details. | explainlikeimfive | http://www.reddit.com/r/explainlikeimfive/comments/3i5qas/eli5_why_is_the_shanghai_index_plummeting_right/ | {
"a_id": [
"cudlnr7"
],
"score": [
3
],
"text": [
"There are many reasons, but broadly speaking it has to do with motive. Who is motivated to see stock prices to go up and down? Simply speaking there are 3 main parties to this, shareholders, management and the government. \n\nShareholders want to see the price of a stock go up. The higher it goes the more they can sell it for when they retire, or cash out to buy a home a car or something. Shareholders generally have no real reason to see the price go down. \n\nCompany management like wise have little motivation in seeing the price of their stock go down. The higher it is, the more successful their company looks, the better rewards they'll receive for creating value for the company/ shareholders. Management is generally not interested in seeing the stock price fall.\n\nShareholders and management in China are similar in their motivation to shareholders and management in the US. No one wants to see their portfolio/ stock price fall. The difference is the ability to profit from incorrect pricing. It is easier outside of China to recognize and profit from errors in stock pricing. This will tend to push stock prices down to generally accepted true value.\n\nBut where does the government fit in? The value of companies to governments is usually a source of pride, or a badge of success, and while governments would like to create environments where companies can succeed, and they usually don't get too involved. However, in China it is more than that. The government is actively involved in companies. The Chinese government owns many companies and has a stake in others. Party members can be appointed on the board or in leadership positions within companies. The government is the management and the shareholders. So are they motivated to see the price of stocks fall? \n\nBetting against state owned companies in such an environment could easily be seen as antagonistic towards the government and state. This could easily scare off the people who would have the knowledge and ability to do so. If you know a state owned company is over-priced but think you'll suffer some type of penalty or censure if you make a move against it, is it really worth the trouble? Why not park your money somewhere you feel is safer and let it remain someone else's problem? \n\nAs a result of this environment many stocks prices have climbed to prices they don't belong and people aren't sure where they should have been. So everyone is trying to sell off their stock and save what is left of their investment. There are price bubbles all over the world in many different forms varying from beanie babies to housing securities. The market and government are yet to figure out an accurate way to predict and prepare for them. That being said, there are ways to mitigate and warn. Primarily this is through independent analysis of stocks and companies. Many investment firms have analysts that go through a company's statements and records in order to figure out the truthfulness of those records and ascertain the company's value. Smaller companies may pay organizations like Bloomberg or Zachs to conduct an analysis of their own company to provide transparency to their stock holders (not entirely independent, agreed). \n\nThe point is, the ability to independently analyse companies without repercussions, and to act on that analysis helps to avoid and soften the blow. A Chinese stock market isn't simply a matter of national pride, its a matter of control. The Chinese government maintains tight control of their currency and routinely interferes in the stock market, which along with penalties for non-positive feedback makes analysis difficult and unreliable.\n\nEDIT TLDR: Prices are too high, no one knows what the price should be so everyone is selling their stock."
]
} | [] | [] | [
[]
] |
|
3tyqn5 | how do solid state hybrid drives work? | I don't understand how a regular hard drive can work with a solid state drive at the same time. | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/3tyqn5/eli5_how_do_solid_state_hybrid_drives_work/ | {
"a_id": [
"cxabzr2",
"cxaf4ls",
"cxafhh8",
"cxah5t9",
"cxaiiwu",
"cxaj7m9",
"cxamf9y",
"cxaurxj",
"cxavk14",
"cxaxe2n",
"cxaxr7j",
"cxaznjh",
"cxb1xim"
],
"score": [
180,
1600,
60,
11,
31,
4,
5,
4,
5,
57,
2,
2,
2
],
"text": [
"SSD chips are fairly small now, and can be integrated into the larger hard drive. They work by storing most data in the hard drive, but some of it is copied to the SSD. What is stored in the SSD is decided by optimization algorithms. Simply put, the stuff you use the most. \n\nEDIT: some hybrid drives just work as two separate drives in the same unit. So you can manually decide what goes where. ",
"Imagine the sshd (solid state hybrid drive) is a refrigerator.\n\nA few times a day, you come back to the fridge to get a glass of juice. You take the juice out. Pour some in a glass and put the juice back. Presumably near the front of the shelf. Because its at the front of the shelf, you can access it very quickly. But there is not much space on the front shelf, so you only put a few things there.\n\n Now, its time to make some dinner. You need pickles, which you only use maybe once a week. So they are in the back of the fridge, where there is a lot more space, but its harder to reach them. So it takes a little longer for you to get at them. But you eventually succeed, and put them right back where you found them to be used next week.\n\nNow, to explain how an sshd works, replace the food items above with computer files, front shelf with ssd, and back shelf with hdd.",
"It's just a ssd cache. Don't ever buy one, they are horrible. Pony up for a real ssd. ",
"To elaborate on what intelnavi said, if you're thinking about buying one, just buy a straight up SSD. Less freezing, downloads are much faster, and your drive will last longer!",
"Let's make it even easier. \n\nSSD - Closet in home, HHD - Storage Locker down the street. One hold jackets to get quickly, the STorage Holds old jackets, in case you need to pull out an older coat/file.\n\n",
"[LinusTechTips - Seagate SSHD Hybrid Drive Unboxing & Technology Explanation](_URL_1_)\n\n\n[Techquickie - SSD Caching as Fast As Possible](_URL_0_)",
"There are two kinds of Solid State Hard drives.\n\nThere's the kind that Seagate makes where they pair a 500GB HDD with an 8GB SSD. The SSD in this type of Hybrid is mainly used as a Cache. There's a controller inside the Hard Drive that monitors your most frequently used data and the controller puts that data onto the fast SSD portion. The data that gets used less is stored on the mechanical HDD. Btw, this kind of Hybrid only assigns one Drive letter.\n\nThen there's the Solid State Hybrid drive like Western Digital has where they pair a 1TB HDD with a 120GB SSD into one case. This type of drive treats the two types of Hard Drives as separate drives and will assign two different Drive letters to them. ",
"How can I optimize my hybrid hdd? I want to make my laptop start faster. ",
" > I don't understand how a regular hard drive can work with a solid state drive at the same time.\n\nThe same way you hard drive works with RAM at the same time.",
"You don't need all of these bullshit metaphors.\n\nA hybrid drive contains both slow magnetic storage and fast chip (NAND) storage. It keeps the stuff you use often on the fast chip storage, and the stuff you use less frequently (or never) on the magnetic storage.\n\nThis works because SSD's are expensive, and most people access the same data over and over. If you have 100GB of data, you're probably only regularly accessing < 5GB of that, if even that. Keeping all 100GB on expensive chip storage is a waste. Put most of it on the slow magnetic storage, and the stuff you access frequently on the fast chip storage, and you can save tons of money and still experience the benefits of your most used applications launching quick.\n\nThis only makes sense when the cost of storing all your data on an SSD is too expensive, which makes the added complexity of \"hybrid\" worth it. But as SSD's drop in price, the complexity becomes less and less worth it, to the point where hybrid drives are a complete waste of money.\n",
"SSHD contains a magnetic disk and NAND Flash. NAND flash has much faster access time than the magnetic disk.\nMost Frequently accessed data is copied into the NAND flash from the magnetic disk. Drive will update what is stored in the NAND flash based on the data being accessed by the user.\nThe drive will first look in the NAND flash for data. If it's not in the NAND flash, it will get it from the magnetic disk.\n",
"Imagine you have 2 special rooms in your basement.\n\nOne is easily accessible, just behind a locked door. The second room is; let's say underneath the first room down a ladder and behind a few locked doors.\n\nLet's say you like kids and as a babysitter you need to organize where you put your kids. Now some kids are great and you love to visit often. Some are bad and you don't like to visit them often but you keep them around just in case.\n\nThe lower room is much bigger, but you really only visit a few kids at any given day anyway.\n\nSo what you end up doing is prioritizing because your lazy by keeping the kids in the easy to access room, while keeping the kids you don't visit often in the hard to access hard to get to the kid room.\n\nThat's basically it. But let's say one of your good kids get's boring, and one of the bad kids you miss and want to spend time with. Well you can put the good kid down in the lower room, and bring the bad kid up in the good room through the ladder and leave him/her there to visit more if you need to.\n\nThat's basically how SSHDs work. HDDs are slower, so you need to go through stairs/crawlspaces/ladders(Slower access) to get to things you don't use often, while a SSD is quick (Open a door, retrieve) but not very big.",
"Hybrid drives have two physical disks.\n\nThe main storage comes from the spinny disk, which is big on size and *comparatively* low on read and write speed. This is mostly due to limitations of physics - the way spinny disks have to store and recall data on them, where the part of the disk which does the reading and writing has to cope with inertia, gravity and physically how far apart from each other the portions of the files you're working on are stored, because disks don't always physically store data in just one piece.\n\n*I say comparatively, because spinny disks these days are pretty darn fast.*\n\n & nbsp;\n \nThe 'hybrid' part of the SSHD - the SSD - is big on speed and comparatively low on size. It has no moving parts, so can store and recall data much faster -- the thing mostly slowing it down is its own miniature computer managing how the the memory chips are used.\n\nSSDs also benefit from having evolved from the same kind of storage used for many years as temporary memory - where incredibly fast speeds for reading and writing data were the most important factor.\n\n & nbsp;\n \nThe hybrid drive's miniature control computer decides which data is accessed most often, and keeps it in (or moves it to) the SSD part, permanently or until it decides it's not being used any more. Other data is kept on the slower, but still fast, spinny disk, where it can be moved back on to the SSD if it becomes very popular.\n\nThe SSD doesn't add more *overall* storage, it just allows the hybrid drive to respond more quickly when it's asked to store or recall a popular file.\n\n & nbsp;\n \nUsing the analogy of an archivist...\n\nImagine the hybrid disk is an archivist dealing with colleagues' documents. New documents go into a small tray on the archivist's desk, right next to where they sit. If it's not asked for after a certain amount of time, the archivist moves it into long term storage (a big room down the hall).\n\nThe archivist treats all new documents equally and only moves them into long term storage if they've not been requested for a week. However, when it gets very busy, as the desk tray can only hold 50 or so documents, the archivist also moves the oldest documents in the tray to long term storage when it fills up.\n\n & nbsp;\n \nA new document is given to the archivist so it goes into the tray. After a week without any requests for it, the archivist takes it to the long term storage.\n\nSeveral days after that, a colleague asks for the document, so the archivist goes down the hall, retrieves it from the long term storage and puts it back in term storage when the colleague returns it.\n\nIn the meantime, the archivist receives a second document, which goes into the tray on the front desk like all the others. However, before the archivist moves it to long term storage, several colleagues call and ask for a copy of the document. The archivist can quickly fulfil the requests, as it's in the tray on the their desk. No walk down the hall to long term storage needed!\n\nThis second document ends up being very popular, so the archivist keeps it in their desk tray. The first document is only requested once every six months, so it stays in the storage room."
]
} | [] | [] | [
[],
[],
[],
[],
[],
[
"https://www.youtube.com/watch?v=FI0JmKp1v4U&feature=iv&src_vid=YQEjGKYXjw8&annotation_id=annotation_3231545099",
"https://www.youtube.com/watch?v=vaxBmTTTWMo"
],
[],
[],
[],
[],
[],
[],
[]
] |
|
fx9ya2 | when you can see the moon during the day, does the mean the other side of the planet can't see the moon at night? does this have to do with the phases of the moon? | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/fx9ya2/eli5_when_you_can_see_the_moon_during_the_day/ | {
"a_id": [
"fmszovk",
"fmtcprx",
"fmtd51t",
"fmtj69y"
],
"score": [
9,
2,
5,
2
],
"text": [
"Yes. Sort of. If the moon were on the horizon at noon, then someone on the other side of the planet could see it for about half of the night. See [this](_URL_0_) link for a diagram. Hopefully it'll all be clear with that.",
"The moon is far away. You seeing the moon during the day only means some of the people who are in a night time position don't see the moon. If you draw a circle on a far side of a piece of paper and then a dot on the other, you can draw the observable with simple lines from the dot to the circle. If you add another paper with a sun, you can represent day and night.",
"The earth turns faster than than the moon orbits the earth. So the earth does a complete spin, called a day, before the moon completes its orbit, called a month (roughly). The position of the moon in the sky is a function of the time of day. Over a day the moon doesn’t move enough to be noticeable. So everybody on the planet gets a chance to see it as it appears to you that day. The appearance of the moon is a function of the month, that is, as the moon moves through its orbit around the earth, the angle of the sunlight hitting it changes. Over the course of several days the appearance of the moon changes, and the time it appears to you, and everyone, changes. But it takes longer than a day to notice.",
"When there's a full moon, the moon rises at sunset and sets at sunrise. \n\nWhen there's a new moon, the moon is close in the sky to the sun, so you can't see it. \n\nAt midnight(according to the sun), you can see any moon that's more than half full. \nAt sunrise, you can see any moon that's waning. \nAt sunset, you can see any moon that's waxing. \nAt noon, have line of sight to moons that are less than half full, but if it's close to a new moon the atmosphere might be too bright to see it."
]
} | [] | [] | [
[
"https://images.app.goo.gl/D5eHLarKGMMkq2zt8"
],
[],
[],
[]
] |
||
85i7wz | why metal nanoparticles, like gold, exhibit surface plasmon resonance? | I read a lot of paper but I still don't understand... | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/85i7wz/eli5why_metal_nanoparticles_like_gold_exhibit/ | {
"a_id": [
"dvyltlo"
],
"score": [
3
],
"text": [
"When photons hit the metal nanoparticle, they excite the “sea of electrons” in the metal and form an oscillating surface wave (called the surface plasmon).\n\nWhen you use photons of different wavelengths, the oscillating wave will change in amplitude and will absorb a greater/lesser amount of the incoming light. The amount of energy of the osciallting wave is exactly equal to the absorbed photon, thus Surface Plasmon Resonance."
]
} | [] | [] | [
[]
] |
|
eoezxm | if we never actually touch something due to the pauli exclusion principle what actually causes friction? i thought it would simply be atoms jostling each other creating heat, but if they don't actually touch what is causing them to move and create heat? | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/eoezxm/eli5_if_we_never_actually_touch_something_due_to/ | {
"a_id": [
"fecdp72"
],
"score": [
2
],
"text": [
"This comes up a lot on this sub, and mostly comes down to a a misunderstanding of what \"touching\" means. \n\nFirst off, it's not the Pauli exclusion principle, that prevents things from \"touching\", but rather electrostatic repulsion between electrons. The Pauli exclusion principle basically says \"Atoms have slots for electrons, and no matter what, only one electron is allowed per slot\". Electrostatic repulsion means that electrons, which have the same charge, repel each other. You can try this yourself by rubbing balloons against your hair and seeing how they repel each other afterwards. \n\nNow, electrons repelling each other looks a lot like atoms having a skin around them. Electrons don't orbit around the atom like planets around the sun (the typical model of an atom you see in pop culture is 100 years out of date), but rather as a cloud around the nucleus. Think of an object as being a bunch of balloons taped together. Atoms are mostly empty space, and so are the balloons, but that doesn't make much of a difference. The surfaces of the balloons touch and push against each other, repelling, sometimes sticking a bit, deforming each other, etc, *even though it's mostly just air*. Electrons and atoms are just like that. They interact by pushing on each other with electric fields, and this is what it means for something to \"touch\": their electrons are pushing on each other. \n\nOverally, the view of atoms as empty space, the Pauli exclusion principle, and other details mostly doesn't matter beyond physics and some details of chemistry. Once you zoom out a little bit, you can lose a lot of the details and still have totally functional details. It's how we've done great work in science for hundreds or thousands of years while not knowing the structure of the atom until about 100 years ago"
]
} | [] | [] | [
[]
] |
||
2rh8ko | what is the point of feeling certain emotions (mainly looking at anger)? | Why do humans feel anger? There doesn't seem to be any real gain from feeling angry towards something or someone. | explainlikeimfive | http://www.reddit.com/r/explainlikeimfive/comments/2rh8ko/eli5_what_is_the_point_of_feeling_certain/ | {
"a_id": [
"cnfv59i"
],
"score": [
2
],
"text": [
"Its part of survival if someone is stealing your food everyday you need to feel anger to stop it. Without it you would constantly be taken advantage of. "
]
} | [] | [] | [
[]
] |
|
4rdyix | why are 1st 2nd and 3rd unique, and every number following gets the "th"? | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/4rdyix/eli5_why_are_1st_2nd_and_3rd_unique_and_every/ | {
"a_id": [
"d50avq5"
],
"score": [
34
],
"text": [
"The word \"first\" comes from a very old English word meaning \"before all the others\". The basic word was \"fore\", meaning \"forward\", \"ahead\"; \"fyrst\" was the superlative, and meant \"most fore\" -- so the phrase \"first and foremost\" is actually redundant.\n\n\"Second\" is a word borrowed from Latin: \"secundus\" meant \"the one after\", and comes from the same root as our word \"sequel\" -- that's why the *second* movie in a series is a *sequel*, it's the one that comes after the one that comes before all the others.\n\nThe ordinals all ending in \"-th\" come from a much older suffix, so old that it comes from a language that was never written down and so we can only guess at it. Linguists call this language \"Proto-Germanic\", because it was the ancestor of all the Germanic languages, of which English is one. Using an asterisk to show that they're really only guessing, linguists say that our modern \"-th\" ending comes from the Proto-Germanic \\*-tha-, which is thought to mean that whatever is described by the rest of the word is complete -- so \"fourth\" would mean something like \"the thing that completes the set of four things\".\n\nI left \"third\" until last because I'm not completely sure -- and a quick google hasn't turned up anything helpful -- whether it comes from the same \\*-tha- particle. What I do know is that it was originally \"thridda\", so I think it's likely that the \"-dda\" comes from \\*-tha-, I just can't confirm it. In any case, the word underwent what's called \"metathesis\", where some of the sounds get swapped around: in this case, the \"r\" and the \"i\" got swapped, so we say \"third\" instead of what would be expected, \"thrid\"."
]
} | [] | [] | [
[]
] |
||
654jzy | how can i protect my internet browsing data from my isp? | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/654jzy/eli5how_can_i_protect_my_internet_browsing_data/ | {
"a_id": [
"dg7dpfb"
],
"score": [
4
],
"text": [
"the best way is to write your representative and tell them that you don't approve.\n\nTechnical solutions include using VPN, but those have drawbacks when it comes to your internet speed.\n\nRight now your ISP can see what websites you visit because they are the ones through which those websites are send to you.\n\nIf you visit websites with https:// in front of it the ISP can tell which server you were talking to but not which specific page you visited. For example they can tell you looked at reddit but not if you looked at a post on /r/nsfw or /r/explainlikeimfive as long as it goes via https.\n\nIf you use a vpn all your traffic goes through a certain server owned by the people who operate the vpn. Your ISP know that you are communicating with a vpn but not where the connection goes from there. The downside is that the vpn server becomes a bottleneck that slows everything down. Streaming HQ videos or playing online games though a vpn is not going to work very well. It will also likely cost money (There is no such thing as a free lunch and you should probably beware of anyone trying to give you a service that cost them money to create for free).\n\nIn the end there is no way to 100% keep what you are doing online from the people through who you are going online with.\n\nYou can compare it to an old fashioned letter carrier. if you send a postcard the mailman will be able to read it (http) if you send a letter in an envelope (https) the mailman will not be able to easily read the letter but he will still no who is sending a letter to whom. they will also be able to make some educated guesses based on the size and shape of the letter.\n\nIf you use a vpn you just send the letter in an envelope inside another envelope to a middleman whose job it is to unpack the outer envelope and send the inner one along. The mail carrier will be able to know that you are sending letters to such a service, but now who the ultimate recipient is. the downside is that you have to trust and pay the guy whose job it is to unpack the envelopes and send them on."
]
} | [] | [] | [
[]
] |
||
1y3bnz | big city vs small town. why do people (even strangers) seem friendlier in small towns? | explainlikeimfive | http://www.reddit.com/r/explainlikeimfive/comments/1y3bnz/eli5_big_city_vs_small_town_why_do_people_even/ | {
"a_id": [
"cfgzfny"
],
"score": [
2
],
"text": [
"Same quality of people, just a different environment. When you live around fewer people, every social encounter becomes markedly more valuable to your social life. \nIn urban settings, the vast number of people allows you to practice social trial and error a bit more. The demand for friendship is the same, but the supply of potential friends is so much higher it can lower the stakes a bit. \n\nIt's pretty much just supply and demand."
]
} | [] | [] | [
[]
] |
||
6qu58z | if i fell into a literal bottomless pit how long would i survive? what would be the cause of my death? | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/6qu58z/eli5_if_i_fell_into_a_literal_bottomless_pit_how/ | {
"a_id": [
"dl01psy",
"dl0277a",
"dl05kqg"
],
"score": [
2,
8,
5
],
"text": [
"Playing 20 questions then not beating death in a game of battle ships. _URL_0_ Note: this answer is as serious and just as likely to happen as the question. Probably more likely, because the only endless fall would be space or being caught in a event horizon of a super massive black hole, which without protection, would probably give you as long as it takes for your suit to depressurize and you explode or you run out of air and suffocate.",
"Assuming you've managed to keep air out of the hole, then after about 22 mins, you'll be falling/flying through the Earth's core incredibly fast.\n\nMore than likely, you'd be quite well cooked already by that point.\n\nOh, make sure to position your pit on the poles. Otherwise the Earth's rotation will swiftly slam you into the side of the hole, and you probably won't live long enough to be cooked alive.\n\nIn the slightly more likely scenario that you are unable to keep a vacuum in your bottomless pit, it'll take you more like 20 hours to get to the core due to air resistance.\n\nAgain, though, you'll be very, very dead due to the heat.",
"Imagine instead you are trapped in one of those indoor skydiving machines, it works out to about the same thing.\n\nPhysically you would be fine, if not a little uncomfortable, and find it a little difficult to breathe. You would get a little chilly from the wind, and that would also dehydrate a little more quickly. In fact, dehydration is what would kill you if hypothermia wasn't an issue."
]
} | [] | [] | [
[
"https://www.youtube.com/watch?v=PA5ryowAyLk"
],
[],
[]
] |
||
4fyt63 | how do kangaroos become so muscular? | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/4fyt63/eli5how_do_kangaroos_become_so_muscular/ | {
"a_id": [
"d2d44tn",
"d2d51e0",
"d2d72b7",
"d2dmwuh"
],
"score": [
6,
70,
26,
3
],
"text": [
"The males, in particular, do quite a bit of fighting, which makes them muscly, but I suspect more important is that they have very low fat levels, which would make even wimpy bods look like Charles Atlas.",
"Genetics, they are genetically predisposed to develop substantial amounts of muscles in the legs and tail to enable them to hop at speed to avoid predators, as well as muscles for fighting other males.",
"Muscular wild animals usually get that way from myostatin inhibition. \n\nA good example of myostatin inhibition is the bully whippet which occasionally occurs when you mix two whippets:\n\n_URL_0_",
"Kangaroos naturally don't store much fat in their muscles. It gives them that hugely ripped look. \n\nA major reason is the way they walk as well. When going at full speed kangaroos hop. But at slow speed they use their arms and tail to manouver. They walk by firmly putting their tail on the ground whilst holding their weight with their arms. It's like an extended plank exercise. They move their hips forward and take the step, then repeat. They are pretty much doing plank walks all day. Now remember these big reds can weigh 100kgs at times. If you did plank walking exercises for hours a day, your arms and shoulders would be ripped as well. "
]
} | [] | [] | [
[],
[],
[
"https://www.google.com/imgres?imgurl=https%3A%2F%2Fcdn.empowernetwork.com%2Fuser_images%2Fpost%2F2013%2F03%2F01%2F8%2F3a%2F22ae%2F540_293_resize_20130301_83a22aea83165aa0c442def38f14fe3f_jpg.jpg&imgrefurl=http%3A%2F%2Fadil1227.empowernetwork.com%2Fblog%2Fschwarzenegger-dog&docid=xd-wlT3ZOVhwyM&tbnid=3cMe1aAiaSILFM%3A&w=336&h=293&hl=en-us&client=safari&bih=559&biw=375&ved=0ahUKEwiHmuWC0KLMAhXMsYMKHf1YCyIQMwgqKAcwBw&iact=mrc&uact=8"
],
[]
] |
||
5in53u | what is modal jazz? how does it sound different? | what is it? | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/5in53u/eli5_what_is_modal_jazz_how_does_it_sound/ | {
"a_id": [
"dba0n3r"
],
"score": [
2
],
"text": [
"Modal jazz has no, or very minimal, chord changes. While artists during the bebop area were infatuated with chord changes, Miles Davis and John Coltrane began an era of modality. Their music did not rely on chord changes, so it was much more light and relaxed in texture. It was often labeled as \"cool\" jazz, as it had that cool feel to it since it was absent of quick chord changes. "
]
} | [] | [] | [
[]
] |
|
450312 | how can we have confident projected winners in elections with less than 10% of votes reported? | This bothers me as well as my spouse. I can only speculate that it is based on previous voting results, or something similar. I'm not sure how they do this with primaries, like in NH. Is it really just an educated guess, or is there more to the numbers? | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/450312/eli5_how_can_we_have_confident_projected_winners/ | {
"a_id": [
"czu732c",
"czu7crb",
"czukekr",
"czunj4g",
"czuo8xr",
"czuwq98"
],
"score": [
23,
3,
6,
2,
2,
2
],
"text": [
"it is kind of like an educated guess except that there are sound mathematics behind it. once you count a certain percentage of the votes and a candidate is in the lead by a certain amount you can calculate that the odds of someone else winning are less than a gazillion to one. the government counts all votes for the official result but the news wants to give people information quickly. ",
"It depends on margin of victory and the correlation between exit polling data and official results for sample precincts.\n\n\"Shortly after poll closing time, CNN may make projections using models that combine exit polls and actual votes. This happens in closer races. For extremely close races, CNN will rely on actual votes collected at the local level. These are the races that cannot be projected when the polls close from exit polls or even from actual votes collected at the sample precincts mentioned earlier. The projection for these races will be based on a statistical model that uses the actual votes. If it is too close for this model to provide a reliable projection, CNN will wait for election officials to tally all or almost all the entire vote.\"\n\n_URL_0_",
"Statistical math, basically. There are some neat real world applications that would blow your mind.\n\nHere, play with this: _URL_0_\n\nIn most polls you come across a confidence level of 95% is the standard, and the confidence intervals I usually see are plus/minus 4%. With those parameters they only need to sample 600 people from a population of 320 million.\n\nIf they were trying to be extremely accurate (99% confidence level plus/minus 1%), it would require a sample size of about 16,000.",
"There are two things they use, only one of them is the reported vote totals. \n\nThe other is exit polling where they wait near polling places and ask people who they voted for. They have a good idea how far off those samples might be and how many people are likely going to vote in each area. They estimate what the likely result is and what the likely error in that estimate is and if there's still a clear winner even with the possible error they predict the result. \n\nIf they can't predict then as the night goes on they replace the samples for each area with the reported results as they come in and this reduces the probable error in their estimates, eventually they have a good prediction. ",
"A good rule of thumb in statistics:\n\nAs long as the sample is random, a sample size of 1000 is reliable enough for most purposes. It doesn't matter much if the population is 2000 or 2 000 000 000, as long as the sample is randomly selected.",
"Its based on the counted votes as well as exit polling and demographics. As long as the reported precincts represent a broad array of demographics they can be a good benchmark. \n\nSome can simply be called based on demographics and history alone, though this is more the case with the general. For instance the networks will typically call MA for the Dems and AL for the GOP as soon as the polls close, based on the history of the state and preelection polling."
]
} | [] | [] | [
[],
[
"http://edition.cnn.com/2014/10/28/politics/cnn-election-projections/"
],
[
"http://www.surveysystem.com/sscalc.htm"
],
[],
[],
[]
] |
|
5vwysj | how does vx nerve agent work? | How does it take to kill you? How was it made? Is there anything Kim Jong Nam could have done to save his life, or was he as good as dead the moment the nerve agent touched his face?
[Full story.](_URL_0_) | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/5vwysj/eli5_how_does_vx_nerve_agent_work/ | {
"a_id": [
"de5in7p",
"de5k5ph"
],
"score": [
5,
3
],
"text": [
"It's lethal because it blocks a key enzime in the cycle of muscle contraction. The cause of death is paralysis of diaphragm, the muscle responsible for respiration. Antidotes exist, but you need to deliver them as soon as possible, because respiratory arrest ensues fast. ",
"To give you an idea of how quickly antidotes/countermeasures have to be administered, I know someone going through NBC training that got hit with a small dose of a similar agent on his arm.\n\nThey immediately applied two injectors of counter agents and got him to a hospital. He spent about a week there, and he was fine. Getting it applied right to the nose and then having to wander around a bit would've been difficult to counteract even if the people he went to for help knew what was going on and had the right equipment."
]
} | [] | [
"http://mobile.reuters.com/article/idUSKBN16303Z"
] | [
[],
[]
] |
|
8zirm6 | why is there a need of an additional checkin process in flight travel. why cant we just use the tickets to board the plane? | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/8zirm6/eli5_why_is_there_a_need_of_an_additional_checkin/ | {
"a_id": [
"e2j19ij",
"e2j1day"
],
"score": [
16,
4
],
"text": [
"Having passengers check in before boarding allows the airline to confirm which passengers have actually shown up for the flight. This can be important if a flight is overbooked (too many passengers), or if a flight has open seats that could be filled by standby passengers.\n\nIf they waited until boarding to check all of that, that would be quite a time crunch at the last minute. ",
"It is a final confirmation that you will actually show for the flight and allows the airline to plan on how many bags you will bring, any special accommodations that you require, a reminder of restricted or prohibited items that you can or cannot bring with. By doing this it can save time when you arrive at the airport.\n\nAs a ramp agent for a major airline, it still surprises me when I watch the gate agent and see how many local passengers are missing right when the doors close that never show up."
]
} | [] | [] | [
[],
[]
] |
||
xu700 | where credit card companies and banks get all that money to loan out? | Credit Card companies pay for all kinds of people's stuff and a lot of people carry a balance and don't pay until later. I understand that they make money from the interest, but where do they get the massive amount of money to front to the buyer? Also, bank loans too. | explainlikeimfive | http://www.reddit.com/r/explainlikeimfive/comments/xu700/eli5_where_credit_card_companies_and_banks_get/ | {
"a_id": [
"c5pltew",
"c5ponka"
],
"score": [
2,
3
],
"text": [
"Banks get it from all the money people deposit, and credit card companies get it through loans from banks. (That's why interest exists; the bank is paying you to use your money for loans.)",
"Also, by the magic of [fractional reserve banking](_URL_0_), a lot of what the companies loan out is not \"real\" money (I'm using it as a very loose term), as in they loan out money that they do not actually own.\n\nLet's say I deposit $100 in a bank. I may want to withdraw this at any time, so if I'm the only person depositing money at the bank, it will not be able to loan out my $100. However, let's say 10,000 people all deposit $100 in a bank. Then there will be $1,000,000 in the bank. The bank might loan out $800,000 even though the money doesn't belong to it, but rather to the depositors. The bank is guessing that no more than 2,000 of those people will want to withdraw their $100. If it's wrong, then the bank will be out of money, but mathematicians at the bank calculate the risk of that happening and make sure it's very small."
]
} | [] | [] | [
[],
[
"http://en.wikipedia.org/wiki/Fractional_reserve_banking"
]
] |
|
bu77xi | why are banana's considered berries? | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/bu77xi/eli5_why_are_bananas_considered_berries/ | {
"a_id": [
"ep7vk46"
],
"score": [
9
],
"text": [
"A berry is a juicy fruit with seeds rather than a stone inside the fruit body, it doesn't have to be round so a banana fits the description of a berry."
]
} | [] | [] | [
[]
] |
||
aaznlc | what does the lds church control in utah/salt lake city government? | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/aaznlc/eli5_what_does_the_lds_church_control_in_utahsalt/ | {
"a_id": [
"ecwa82s",
"ecwaaz7"
],
"score": [
10,
2
],
"text": [
"Officially, nothing. Giving the LDS church official control over any level of government would indeed violate the First Amendment.\n\nHowever, the opinions and desires of the LDS church strongly influence the voters in Utah and Salt Lake City. So, if a politician came out in favor of a policy that the church disagreed with, you can be sure they would let their members know and that politician would likely not win an election.\n\nSo, local politicians try to stay in the good graces of the church in order to stay in the good graces of the church's members. It's similar to any large block of voters who vote together.",
"In short, the LDS Church is a multi billion dollar church. They have members in the government and have plenty of money to help persuade."
]
} | [] | [] | [
[],
[]
] |
||
2vcnkc | if i were to copy a work of art w/o the intent of stealing it, could i be held accountable for forgery or plagerism? | explainlikeimfive | http://www.reddit.com/r/explainlikeimfive/comments/2vcnkc/eli5_if_i_were_to_copy_a_work_of_art_wo_the/ | {
"a_id": [
"cogforf",
"cogfr7o"
],
"score": [
6,
2
],
"text": [
"It depends on what you actually do with the artwork.\n\nIf you attempt to pass the artwork off as your own for any reason, its plagiarism.\n\nIf you attempt to sell your copy claiming it is the original, then it is forgery.\n\nIf you attempt to profit in anyway using copies of the artwork, then it is a copyright violation.\n\nThere is some crossover between the categories.",
"Forgery is an attempt to pass your copy off as an original.\n\nPlagiarism is attempting to pass it off as your own original work.\n\nClassic works of art are routinely duplicated for people without any problem, as long as they're labeled as fake/duplicates. You might get into some trouble if you were *commercially* duplicating a more modern work that still had a valid copyright (ie - created in the last hundred years or so)."
]
} | [] | [] | [
[],
[]
] |
||
aqjzls | how does the constant change between cold and warm weather effect hibernating wildlife? | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/aqjzls/eli5_how_does_the_constant_change_between_cold/ | {
"a_id": [
"egghdk6"
],
"score": [
2
],
"text": [
"It's more than just the temperature, seasonal ques like the shortening of days plays a major role."
]
} | [] | [] | [
[]
] |
||
3ab5xc | where is my bus getting its wifi? | My home router basically broadcasts my physical internet connection. The bus isn't physically connected to a physical connection by virtue of being a fucking bus. So what's the deal?
^Yes ^I ^am ^on ^a ^bus ^and ^bored ^as ^fuck. ^Send ^help ^:( | explainlikeimfive | http://www.reddit.com/r/explainlikeimfive/comments/3ab5xc/eli5_where_is_my_bus_getting_its_wifi/ | {
"a_id": [
"csay2zl"
],
"score": [
3
],
"text": [
"It uses 3G (or 4G) just like your cellphone connection. If you got a wireless hotspot you can use it virtually anywhere you can get cell service."
]
} | [] | [] | [
[]
] |
|
nt6lq | congress ends corn subsidy. how was the corn subsidy bad, and why is it good that it's over? | _URL_0_
I guess I just want someone to break down this situation for me and others. Thanks!
EDIT: corn **ETHANOL** subsidy. | explainlikeimfive | http://www.reddit.com/r/explainlikeimfive/comments/nt6lq/eli5_congress_ends_corn_subsidy_how_was_the_corn/ | {
"a_id": [
"c3bqh3e",
"c3br7u9",
"c3brf77",
"c3bsenz",
"c3bsza1",
"c3btxjp",
"c3bu6eo",
"c3buqdm",
"c3bveze",
"c3bqh3e",
"c3br7u9",
"c3brf77",
"c3bsenz",
"c3bsza1",
"c3btxjp",
"c3bu6eo",
"c3buqdm",
"c3bveze"
],
"score": [
95,
4,
89,
62,
3,
5,
2,
2,
3,
95,
4,
89,
62,
3,
5,
2,
2,
3
],
"text": [
"When I first read this I saw \"porn subsidy.\"\n\nMoving along, things that come to mind:\n\n-Corn that is being used for ethanol isn't being used for food or fodder, causing prices to rise. Keep in mind that in our processed world, corn is used in *everything.* Read the labels on the things at Giant and check for high fructose corn syrup, xanthan gum, maltodextrin, etc.\n\n-Tax money that's being used to subsidize ethanol isn't being spent elsewhere.\n\n-[Some](_URL_1_) have claimed that although it might seem that using corn ethanol is cleaner than using traditional fossil fuels, the farming it requires it might make it more \"expensive\". Ethanol releases [51% less](_URL_0_) GHG than traditional fuel does, but producing corn ethanol requires forest clearing, fertilizers, pesticides, diesel farm machines, transportation, and refinement. Whether that's worse than turning crude into gasoline I can't say, but it might just be.\n\nThe end of the corn ethanol subsidy obviously makes the production of corn ethanol less attractive, which will most likely reduce corn ethanol production. For these reasons, the Democratic People's Republic of Reddit is very pleased.",
"[Here's one side of the argument](_URL_1_)\n\nFor background, their talking about how much Bullshit it is that the government wants to tax fast food and other fatty foods at a higher premium. \n\nIf you want the full episode, which has nothing to do with your question, but is still a great watch, [here you go](_URL_0_)",
"Wish they would kill normal corn subsidies. \n\n- No more HFCS in everything\n\n- Proper animal feed insted of corn\n\n- no more magical 101 uses for corn that is unhealthy as shit. ",
"For a moment I was so excited because I thought that Congress had miraculously, unbelievably managed to end corn subsidies. Then I clicked through and saw that it's only ethanol corn subsidies. A drop in the bucket. Sad.",
"Trying to make fuel from corn is worse for the environment than drilled/refined oil. So there's no need to subsidize its production.",
"short answer:, the ethanol subsidy was a give-away to big agra-business by farm state congressman, sold under the cover of energy independence. the Bio-fuel concept has it's place, but making ethanol from corn has never been economically viable. All it did was raise the price of corn and thus the the price of all the other things it's used in.",
"No one is mentioning what this means for the rainforests in Brazil...\n\nThis law was bad when it was made, but now could cancelling it be even MORE disasterous now that the US is hooked on the \"methadone\" that is corn ethanol, which will now be purchased from South America?",
"I wrote a paper about this in college that I'm very proud of. I uploaded it [here](_URL_0_) if anyone wants to read it in its entirety. Here's a pertinent quote:\n\n > However, when money's involved, short-term monetary gains tend to trump long-term risks to the human condition. Take as an example the environmental impact of farming operations in the American Great Plains. In 2004, U.S. farmers grew 11.8 billion bushels of corn. Some of this became ethanol, some ended up in our food, some was sold to Mexico, some was used to feed livestock, and 1 billion bushels -- 56,000,000,000 pounds -- was wasted because farmers grew more than they could sell. Fortunately for corn farmers, the U.S. government pays subsidies whether they sell their crops or not. Between 1995 and 2009, 73.8 billion dollars of taxpayer money was given to corn farmers as subsidies. Big farming operations get most of the cash -- the top 20% of growers receive an average of $160,669 per year, the other 80% receive an average of $5,672 per year.",
"The corn subsidy caused land that was for food to be converted into land that was farmed to create fuel. This drove food prices way up in other parts of the world, as well as locally, as there was just less corn, and so less food, as corn is everywhere. The amount of corn needed to feed a large population, if used for ethanol instead, would not be enough to fuel the same population. Although it would seem that ethanol burns cleaner and gives off less emissions and is thus better for the environment, the process of producing ethanol requires energy, time, and causes emissions. Production is not perfectly efficient as well, you lose some energy as waste heat in the process. When these factors are taken into account ethanol ends up being 'dirtier' than gas. \n\n\nAlso, it mentions the tariff for Brazilian ethanol; this was a very big problem. The US imported a good chunk of ethanol from Brazil, naturally, this encouraged Brazilian farmers to grow more sugarcane (used to make ethanol like corn). This causes the food shortage issues briefed above, as well as some nasty others. If a farmer is already growing ethanol corn on his entire land, and has enough money (from exporting it to the US) to expand, where are they going to do so? The answer to this question has largely been, unfortunately, the rainforest. Farmers burn down whole acres of rainforest to create more land for farming. This results in a whole slew of problems: loss of biodiversity, GHG emissions (both from burning/machinery and the loss of trees), soil alteration/degradation, destabilization of the environment, and a handful of more subtle effects on global climate. The end of the tariff will likely hurt Brazilian farmers in the short run but the preservation of the rainforest has more long term benefits.\n\nI skimmed some parts and skipped others, will gladly expand if needed",
"When I first read this I saw \"porn subsidy.\"\n\nMoving along, things that come to mind:\n\n-Corn that is being used for ethanol isn't being used for food or fodder, causing prices to rise. Keep in mind that in our processed world, corn is used in *everything.* Read the labels on the things at Giant and check for high fructose corn syrup, xanthan gum, maltodextrin, etc.\n\n-Tax money that's being used to subsidize ethanol isn't being spent elsewhere.\n\n-[Some](_URL_1_) have claimed that although it might seem that using corn ethanol is cleaner than using traditional fossil fuels, the farming it requires it might make it more \"expensive\". Ethanol releases [51% less](_URL_0_) GHG than traditional fuel does, but producing corn ethanol requires forest clearing, fertilizers, pesticides, diesel farm machines, transportation, and refinement. Whether that's worse than turning crude into gasoline I can't say, but it might just be.\n\nThe end of the corn ethanol subsidy obviously makes the production of corn ethanol less attractive, which will most likely reduce corn ethanol production. For these reasons, the Democratic People's Republic of Reddit is very pleased.",
"[Here's one side of the argument](_URL_1_)\n\nFor background, their talking about how much Bullshit it is that the government wants to tax fast food and other fatty foods at a higher premium. \n\nIf you want the full episode, which has nothing to do with your question, but is still a great watch, [here you go](_URL_0_)",
"Wish they would kill normal corn subsidies. \n\n- No more HFCS in everything\n\n- Proper animal feed insted of corn\n\n- no more magical 101 uses for corn that is unhealthy as shit. ",
"For a moment I was so excited because I thought that Congress had miraculously, unbelievably managed to end corn subsidies. Then I clicked through and saw that it's only ethanol corn subsidies. A drop in the bucket. Sad.",
"Trying to make fuel from corn is worse for the environment than drilled/refined oil. So there's no need to subsidize its production.",
"short answer:, the ethanol subsidy was a give-away to big agra-business by farm state congressman, sold under the cover of energy independence. the Bio-fuel concept has it's place, but making ethanol from corn has never been economically viable. All it did was raise the price of corn and thus the the price of all the other things it's used in.",
"No one is mentioning what this means for the rainforests in Brazil...\n\nThis law was bad when it was made, but now could cancelling it be even MORE disasterous now that the US is hooked on the \"methadone\" that is corn ethanol, which will now be purchased from South America?",
"I wrote a paper about this in college that I'm very proud of. I uploaded it [here](_URL_0_) if anyone wants to read it in its entirety. Here's a pertinent quote:\n\n > However, when money's involved, short-term monetary gains tend to trump long-term risks to the human condition. Take as an example the environmental impact of farming operations in the American Great Plains. In 2004, U.S. farmers grew 11.8 billion bushels of corn. Some of this became ethanol, some ended up in our food, some was sold to Mexico, some was used to feed livestock, and 1 billion bushels -- 56,000,000,000 pounds -- was wasted because farmers grew more than they could sell. Fortunately for corn farmers, the U.S. government pays subsidies whether they sell their crops or not. Between 1995 and 2009, 73.8 billion dollars of taxpayer money was given to corn farmers as subsidies. Big farming operations get most of the cash -- the top 20% of growers receive an average of $160,669 per year, the other 80% receive an average of $5,672 per year.",
"The corn subsidy caused land that was for food to be converted into land that was farmed to create fuel. This drove food prices way up in other parts of the world, as well as locally, as there was just less corn, and so less food, as corn is everywhere. The amount of corn needed to feed a large population, if used for ethanol instead, would not be enough to fuel the same population. Although it would seem that ethanol burns cleaner and gives off less emissions and is thus better for the environment, the process of producing ethanol requires energy, time, and causes emissions. Production is not perfectly efficient as well, you lose some energy as waste heat in the process. When these factors are taken into account ethanol ends up being 'dirtier' than gas. \n\n\nAlso, it mentions the tariff for Brazilian ethanol; this was a very big problem. The US imported a good chunk of ethanol from Brazil, naturally, this encouraged Brazilian farmers to grow more sugarcane (used to make ethanol like corn). This causes the food shortage issues briefed above, as well as some nasty others. If a farmer is already growing ethanol corn on his entire land, and has enough money (from exporting it to the US) to expand, where are they going to do so? The answer to this question has largely been, unfortunately, the rainforest. Farmers burn down whole acres of rainforest to create more land for farming. This results in a whole slew of problems: loss of biodiversity, GHG emissions (both from burning/machinery and the loss of trees), soil alteration/degradation, destabilization of the environment, and a handful of more subtle effects on global climate. The end of the tariff will likely hurt Brazilian farmers in the short run but the preservation of the rainforest has more long term benefits.\n\nI skimmed some parts and skipped others, will gladly expand if needed"
]
} | [] | [
"http://www.reddit.com/r/politics/comments/nsh90/congress_finally_ends_corn_ethanol_subsidy_after/"
] | [
[
"http://ianrnews.unl.edu/static/0901220.shtml",
"http://blogs.wsj.com/environmentalcapital/2008/02/07/little-carbon-sink-on-the-prairie/"
],
[
"http://www.youtube.com/watch?v=e8av4unUxeE",
"http://www.youtube.com/watch?v=3tw29lv8-V0"
],
[],
[],
[],
[],
[],
[
"http://www.mediafire.com/?4wdg7glarqt6efe"
],
[],
[
"http://ianrnews.unl.edu/static/0901220.shtml",
"http://blogs.wsj.com/environmentalcapital/2008/02/07/little-carbon-sink-on-the-prairie/"
],
[
"http://www.youtube.com/watch?v=e8av4unUxeE",
"http://www.youtube.com/watch?v=3tw29lv8-V0"
],
[],
[],
[],
[],
[],
[
"http://www.mediafire.com/?4wdg7glarqt6efe"
],
[]
] |
|
4ifmii | how, and why do operating systems, and software become outdated? | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/4ifmii/eli5_how_and_why_do_operating_systems_and/ | {
"a_id": [
"d2xnm3r",
"d2xns0u",
"d2xsrp5",
"d2xsunf",
"d2xsz6k",
"d2xt68d",
"d2xvjxv",
"d2ya6ct"
],
"score": [
9,
182,
7,
28,
3,
4,
3,
2
],
"text": [
"programmers are constantly working to improve software. all of it. even the stuff you don't see, like the firmware on your computer's BIOS, even your hard drive's firmware. hardware manufacturers do the same thing, they constantly are working to improve on the hardware. that is their job, after all.\n\nexcept all of those things are interconnected, and sometimes compromises have to be made and they have to leave older designs by the wayside to get something else to work.\n\nover time, they just become obsolete as we've figured out better ways to do things. not always, and plenty of times good software becomes unusable or worthless and the new stuff is terrible. at the same time, new software takes advantage of new advancements and improvements",
"Software becomes outdated when:\n\n* it lacks features that have become commonplace\n* it relies on features in hardware or other software that are no longer being provided\n\nFor example, an application might run in 32 bit mode only. A new OS might decide they are no longer supporting 32 bit mode, and require all software to run in 64 bit mode. That software is now outdated.\n\nOr can be more subtle. A website written in raw HTML without frames or style sheets or javascript might work just fine, but it will look old fashioned and outdated.\n\nOften when software becomes too outdated, the vendor will stop supporting it. If you find a bug, they will no longer fix it or help you work around it, instead they will tell you to upgrade.",
"Think of the system as many layers built on top of each other, with each layer being dependent on the layer beneath it. These layers are constantly being improved upon, changing and adding features so the layer performs its job better and faster.\n\nMost of the time this causes no ill effects on the layer above it, but sometimes it creates what is known as a \"breaking change\", breaking the layer above it (or dependencies on older versions of the layer beneath it). \n\nThis problem is commonly solved either by adding backwards compatibility in the changed layer or by updating the affected layer to reflect the changes in its dependencies.\n\nThe problem is that this adds complexity and sometimes other adverse effects. So you have to do a cost/benefit analysis before supporting older versions of the layer above and beneath the layer you are changing.\n\nSometimes it's just not worth it and it's better to start from scratch and reimplement a layer. This can be done in two ways, either by stopping support for older layers over night and forcing people to upgrade affected layers right away, or by deprecating features you are planning to phase out (meaning they work but shouldn't be used anymore) and allowing time for other developers to make changes to their layers to reflect your future design.\n\nEither way, the end result is that support has stopped for a version of a layer and it is now outdated, because it is deemed not worth supporting.",
"Cars can be a good analogy to explain this.\n\nAsk yourself if you'd drive a car from the 50's to work every day instead of a car that was made this year. You probably wouldn't want to, because the technology is outdated. The brakes aren't as good, there's no power steering, it can't drive as fast, it's not as safe in a collision, there's no Blue-tooth connectivity, no decent speakers, no good air conditioning, no good heating, etc.\n\nWith software and operating systems, the story is the same. For example, you wouldn't want to run windows 95 today because it can't support the hardware from today, it (I assume) has horrible security vulnerabilities that we've since learned about, programs written today rely on operating system features that just didn't exist back then (things like syncing app data between devices automatically), and it wasn't as optimized as today's operating systems.",
"1. Operating systems become outdated if newer software stops supporting it. \n2. Software becomes outdated if it doesn't run on newer Operating systems/Hardware or aren't up to some fundamental standards that are normal today. \n\nReasons are changes in the infrastructure of the OS sometimes because of security reasons sometimes because of newer cleaner/faster concepts. Sometimes the used libraries doesn't care all that much about backward support or had to do changes because of security/speed reasons. And sometimes libraries are stopped beeing developed because they are replaced by newer better libraries and there is no point in competing. And other times the hardware changed so much that it's not possible or would take to much effort to support old stuff.\n\nStrictly most of those reasons aren't breaking the software 100% but require other software (that might not exist and needs to be written) to solve them, like dosbox or a vm or rewriting the software itself. When a software can't run standalone anymore and it could previously it is considered outdated/not supported anymore.",
"Most of the answers in this thread have to do with a lack of features - however, an important reason you are so frequently required to update certain software packages (for example, Flash Player) is the presence of security vulnerabilities.\n\nBecause most commercially-released software is fairly complex, it is entirely possible for a serious hole in its security to make it to release. To run with our example of Flash Player - it might be possible for a malicious coder to write a Flash applet that steals information from your computer, or otherwise does things that a Flash applet is not supposed to do.\n\nEventually, these vulnerabilities (aka \"exploits\") are exposed to the public and/or the development team of the vulnerable program. Usually, this results in an update being pushed to end users ASAP, to prevent more damage. This is why most browsers will disable Flash and other similar programs if they detect you are using an older, more vulnerable version.",
"Well, the windows 98 machine at my work says that neither become outdated if you don't want to pay for an upgrade.",
"I think there are several answers to this question. \n1) Things become outdated due to better available technology \n2) Things become outdated as a vendor marks them as End of Life. \n3) Things become outdated because of non-compliance or incompatibility with something they depended on. \n \n1) is quite self explanatory, if A is strictly better than B, then B is outdated. This only applies if an argument cannot be made for B. For example if B was a free application with fewer features than A, then they could exist side by side.* \n \n2) is trickier. Vendor support generally means that troubleshooting help is available from the vendor and regular security/compatibility patch releases are available. Vendors DO tend to support their products until they release a new version (which is usually situation #1). But sometimes do things like re-brand, or cut product support for other business reasons. When this happens the product is considered End of Life and is now outdated.** \n \n3) is the most complicated and occurs for a host of reasons. It's important to note there is a hierarchical relationship between Hardware > Operating Systems > Software > Other Software. Where if one is outdated, each thing dependent on it becomes outdated unless the vendor supports them under the new conditions. Sometimes though, even if a vendor wants to support them, they are non-compliant and thus considered outdated. \n \nSome examples of #3 are; \n- Windows XP to Windows 7; This introduced a new set of security features referred to as UAC. Many older applications were incompatible with UAC and so became non-compliant and thus out of date. \n- New Browsers removal of silverlight support; Many web apps required silverlight to run, as many browsers don't support silverlight, many older apps are now non-functional. \n \n*Some vendors continue to support older applications/hardware despite being out of date, this is because their customers are often inflexible and will not change immediately. Take for instance Microsoft's support of Windows 7 and 8 despite the release of 10. \n\n**Some vendors continue to support old applications/hardware even though they've been marked as End of Life (though they usually charge for it). These are referred to as legacy applications, or legacy hardware."
]
} | [] | [] | [
[],
[],
[],
[],
[],
[],
[],
[]
] |
||
1ioo7i | why do certain muscles on my body sometimes "pulse"? | Maybe you could also describe it as "twitches".
EDIT: Glad to find out it's normal. Phew. | explainlikeimfive | http://www.reddit.com/r/explainlikeimfive/comments/1ioo7i/eli5_why_do_certain_muscles_on_my_body_sometimes/ | {
"a_id": [
"cb6j7nv",
"cb6jegv",
"cb6jiti",
"cb6jpl7",
"cb6jrr7",
"cb6jtrj",
"cb6kh9q",
"cb6o289",
"cb6o4vo",
"cb6q8dl",
"cb6qeqr",
"cb6x3q3"
],
"score": [
25,
6,
14,
3,
43,
2,
4,
2,
23,
2,
3,
2
],
"text": [
"I've always been told it's stress. What muscles of yours pulse? Mine are mainly in my thigh or my eyelid. Sometimes a pectoral will pulse, but rarely.",
"I get this all the time. Everyday. I get pulses in my calf, in my quads, and hamstrings. The outer thighs as well on the side.\nI Get eye twitches on my eye every so often, but not all the time. \nI get a twitch in my right arm every so often, it's pulsating.\n\nI also have issues with severe cramping... my hamstrings cramp, or try to cramp everyday, it's debilitating and I've been going to doctors and specialists for years trying to figure it out.",
"whenever I look at the twitching area it stops",
"I just thought I was dieing I'm glad this is normal and everyone has it\n",
"The NIH has a nice simple page explaining various causes. They're usually benign and nothing to worry about.\n\n_URL_0_\n\nIf it's concerning you, the first steps are:\n\n* ease up on the caffeine\n\n* make sure you're eating well and not getting a nutritional deficiency, and\n\n* try to manage your stress, maybe with some relaxation or breathing exercises.\n\nLike all medical symptoms looked up on the web, it can be a symptom of some terrible diseases. But, as I said before, usually they just go away and it's nothing to worry about. (Also, are you keeping up your electrolytes after exercising? Seems like that's one of the \"nutritional deficiencies\" that can cause cramping and twitching.)\n\n",
"It's usually a salt or magnesium deficiency. Try a magnesium supplement, I've never taken them but I am on keto, I've heard that there are some better than others so you could ask there which is the best. If that doesn't work just try a bit of salt",
"There are a few factors at play but the benadryl has kicked in on me and I'm passing out.\n\nSomething something, acth enzymes, calcium channels, atp and lack of oxygen (rigor), action potentials (potassium/sodium channels, actin myosin etc... Caffeine mostly affects smooth muscle (arteries) so probably not that besides helping recruitment...\n\nSomeone fill this in, I'm going to bed.",
"Hey guys, please don't look this up on Dr. Google - you will probably freak out! I did a few weeks ago when I typed in 'muscle twitching'. Not a good idea if you have anything closely resembling anxiety. I started going from the occasional daily twitch to about 10 every second - specifically in legs, but the occasional ones in arms, chest, eyebrow, etc,. So clearly stress can have a huge effect on your body and the twitches. \n\nI did a lot of research trying to confirm the fact that I didn't have any major problems (I don't). When you stress your body releases cortisol and adrenaline and this in turn causes your fight or flight response to trigger - twitching, according to some doctors (especially in legs) is just this happening. Nothing to worry about at all. ",
"medical student here...\n\nthese are called \"fasciculations\" (fah-sik-yoo-lay-shuns) they are usually the result of spontaneous firing of what's called the neuromuscular junction or NMJ. the NMJ is where your nervous system physically contacts the muscle tissue that it is intended to control. the NMJ works like a shower head. when neurotransmitter (or water in our shower head example) leaves the shower head and contacts the muscle's surface, it stimulates the muscle to contract. \n\nmost of the time, these contractions are caused by an intentional command arising from your nervous system. however, sometimes, the NMJ will fire spontaneously due simply to a microscopic charge imbalance on the surface of the shower head. \n\nfasciculations are usually harmless but on rare occasions may be caused by certain pathologies. here's the [wikipedia](_URL_0_) page on fasciculations for reference. if you think you're experiencing anything other than occasional muscle twitching, see a doctor.\n\nhope this helps!",
"because of magic",
"Grad student in neuroscience here, \n\n**Background on your muscles**\nI've noticed this in myself and it happened after stretching/working out but most after massages. The reason has to do with two kinds of muscle fibers. There's the extrafusals (extra - outside) that are on the surface, and you can feel them get hard when you flex. They form a big shell around the intrafusals, (intra - inside), which tell your brain how long your muscle is at a given point in time. They are constantly updating a map in your brain that describes where your body parts are in space. Basically, the extras do the lifting, and the intras sense where your limbs are.\n\n**How they work together**\nSo, to send messages to the brain, the intras cannot be slack, they have to be tightly stretched over the length of your muscle, and the degree to which they are stretched is what tells your brain where your parts are. So they are in constant balance with your extrafusals to maintain this tightness to message your brain, that is until you lift something, when a different part of the muscle (called the Golgi tendon organ, not important but interesting to read up on) is activated. Important message, your intras are very dependent on tightness, that is controlled by the extras.\n\n**Why they twitch**\nSo imagine you just got a massage. Your extras got worked and prodded and pressed and so now they are much looser than they were before. Now you have an intra that is used to a certain level of tightness from its corresponding extra, but the extra is much looser than it was before. Your intra now thinks that your muscle is being stretched excessively so it is setting off your stretch reflex (knee jerk, for reference) telling your extra to contract, which you perceive as a twitch. :)\n\ntl;dr the two parts of your muscle are sending different messages to the brain, and the sensory part thinks it's longer than it is, so your brain tells the lifting part to flex (contract) when it doesn't have to",
"I had this once a couple years ago really bad after killing two whole cases of Vanilla Coke. It could be due to excess amounts of caffeine."
]
} | [] | [] | [
[],
[],
[],
[],
[
"http://www.nlm.nih.gov/medlineplus/ency/article/003296.htm"
],
[],
[],
[],
[
"http://en.wikipedia.org/wiki/Fasciculation"
],
[],
[],
[]
] |
|
pn01z | the google and youtube privacy policy changes. | explainlikeimfive | http://www.reddit.com/r/explainlikeimfive/comments/pn01z/eli5_the_google_and_youtube_privacy_policy_changes/ | {
"a_id": [
"c3qnzqp",
"c3qo672"
],
"score": [
9,
7
],
"text": [
"Instead of having a separate privacy policy for each product, Google wants to have one privacy policy that covers all their products. They weren't identical, so some had more changes than others.\n\nOne change, if you can call it that, is that there's a reference to storing your cell phone number. This has a lot of people up in arms, but cell phone numbers have been part of [Google's two-part authentication](_URL_0_) for some time now.",
"Someone still leaves phone books on everyone's porch about once a year in my neighborhood that are filled with thousands of names, personal phone numbers, and sometimes addresses. People complain, but only about the waste of paper they represent. Not being listed is an option, and a valid one, but it isn't the end of the world having your phone number made public. Your personal information is probably easier to find than you think -- go look for it and see for yourself. Not saying you shouldn't be at all concerned, just that there are much, much bigger things to worry about."
]
} | [] | [] | [
[
"http://googleblog.blogspot.com/2011/02/advanced-sign-in-security-for-your.html"
],
[]
] |
||
8hvfez | why do iron infusions (or any other vitamin/mineral intake that your body needs) cause negative side effects | Just had an iron infusion a few days ago and I feel like utter crap, but my body was in desperate need for this mineral. So why do I have such negative side effects? | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/8hvfez/eli5_why_do_iron_infusions_or_any_other/ | {
"a_id": [
"dypisz6"
],
"score": [
2
],
"text": [
"The first noble truth in buddhism is that \"life is suffering\". To put it another way, our nervous systems are calibrated by evolution to always feel uncomfortable. The discomfort of this or that situation is actually the discomfort of your brain being tacked like a fridge magnet onto different situations. \n\nSo consciousness is inherently more painful than unconsciousness. \n\nIf your body is desperately in need to iron that means there are a lot of biological processes that are on hold or have a backed up queue, but they're disabled so whatever connection your consciousness has to those things is registering \"blank\". Just like if your toe freezes it become numb. No activity, no sensation. \n\nSo you add this nutrient and these processes start back up. What was unconscious becomes conscious again, and with that consciousness comes awareness of the state of those processes. They're behind on their tasks and their state is shit. \n\nIt's like if you had a warehouse full of junk, but it was locked and no keys. You need the keys to clean that warehouse. Locked warehouse is hidden from consciousness. Then you get the key. Yes the key permits you to get to a state where you have a nice empty warehouse that's enjoyable, but on first opening that door you have a giant mess in front of you. The mess goes from unconsciousness back into consciousness. \n\nLong story short, your body had a bunch of problems it couldn't even be aware of from lack of iron. You supply the iron and those processes come back online, and the awareness of the problems comes back faster than the solution. "
]
} | [] | [] | [
[]
] |
|
7ub4wq | what happens if a cop uses a speed radar gun while he is driving? does the driving affect what the gun picks up? | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/7ub4wq/eli5_what_happens_if_a_cop_uses_a_speed_radar_gun/ | {
"a_id": [
"dtiwkkx"
],
"score": [
3
],
"text": [
"Yes, the driving would impact the detected speed of the target. However many such systems are connected to the vehicle so it can automatically adjust based on its own speedometer."
]
} | [] | [] | [
[]
] |
||
507djj | raoult's law | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/507djj/eli5_raoults_law/ | {
"a_id": [
"d71s3w7"
],
"score": [
2
],
"text": [
"Raoult's law states that the partial vapor pressure of each liquid in a mixture, under ideal conditions, will be equal to the vapor pressure of the pure liquid multiplied by its molar fraction in the mixture. Vapor pressure is the pressure the vapor of a liquid puts on the surface of the liquid in a closed container. High vapor pressure means a lot of vapor is formed, meaning the liquid easily evaporates. When you mix liquids together, the total vapor pressure will be different than the vapor pressure of each individual part. The way to calculate how each liquid in the mixture contributes to the total vapor pressure is by taking a known value (the vapor pressure of the pure liquid) and multiplying it by the molar fraction it takes up in the mixture. Moles are a unit of molecular measurement. The molar fraction is the number of moles of the liquid of interest over the sum of the moles of each liquid in the mixture. So if I mix 1 mol of water with 2 moles of ethanol, the molar fraction of water is 1/(1+2)=1/3. If water has a vapor pressure of 3.17 and ethanol 5.95 kPa, then the partial vapor pressure of water will be 3.17x(1/3) (1.06 kPa)and the partial vapor pressure of ethanol will be 5.95x(2/3) (3.97). Finally, you can add the two partial pressures together to get the total vapor pressure, which would be 1.06+3.97=5.03 kPa."
]
} | [] | [] | [
[]
] |
||
3ufq3u | mcu ( marvel cinematic universe) | So I am a big fan of all the marvel movies and shows and have seen most of them. I understand the plots from movie to movie most of the time, but not how they are connected. Can someone ELI5 the entire MCU plot? | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/3ufq3u/eli5_mcu_marvel_cinematic_universe/ | {
"a_id": [
"cxeiur6"
],
"score": [
2
],
"text": [
"All the MCU movies (and TV shows) take place in the same universe. That's really about it. Some of them have had some common themes (you see the infinity stones/gems in a bunch), but some are really just a comment or two that may as well be throwaways (like references to \"the attack\" on New York). \n\nThere's no \"MCU plot\", as such. It's just a shared universe. Individual movies and series may have a common plot-line or theme that moves forward (like the infinity gems mentioned above), but a lot are pretty much stand-alone. "
]
} | [] | [] | [
[]
] |
|
2ibpv1 | how does light charge things that glow in the dark? | explainlikeimfive | http://www.reddit.com/r/explainlikeimfive/comments/2ibpv1/eli5_how_does_light_charge_things_that_glow_in/ | {
"a_id": [
"cl0p751"
],
"score": [
6
],
"text": [
"Glow in the dark stuff contains phosphors. Phosphors act kind of like a leaking battery. Light charges them and then they slowly give off light. Depending on which phosphor is in the product will determine how long the light lasts."
]
} | [] | [] | [
[]
] |
||
21zbz6 | how do directors/producers take extra noise/people out when they're filming in busy areas? | I live in NOLA so I often walk through film sets, and I've wondered this a lot. Recently, I walked through NCIS filming on Bourbon, and the area was PACKED with loud tourists trying to get on set/yelling/etc. How do you keep those kind of people out of the finished product? | explainlikeimfive | http://www.reddit.com/r/explainlikeimfive/comments/21zbz6/eli5_how_do_directorsproducers_take_extra/ | {
"a_id": [
"cghusui",
"cghw908",
"cghwldt"
],
"score": [
2,
4,
4
],
"text": [
"Certainly not the full answer, but part of it has to do with selecting the right mic that only picks up sounds from the area they're trying to record. Different mic designs can pick up sounds from all directions, or a very very specific directions.\n\n_URL_0_\n",
"They use microphones that are made to be very directional and only pick up whoever is speaking. Before of after they film the scene, they record the sound of the place without the actors talking. Just the ambient noise. Then they layer them on top of each other so it sounds natural. ",
"In addition to said specialized mics, they also use techniques in post production, called folio and ADR, to recreate the sounds. Sometimes they don't use any audio from the shoot at all, even in less noisy situations. Folio sound effects mean someone recreates the sound in a studio, like a door slamming, keys jingling. For footsteps for example someone in the sound studio would watch the shot, and walk around on a similar surface. Being in a soundproofed room allows them to capture that sound and nothing more. The sounds are layered and timed to the shot, add in some ambience, traffic sound effects etc, and you have a clean audio track. ADR stands for automatic dialogue replacement and is the same idea for talking. The actor acts their part again but in a quiet studio while following along with the video, just like a voice actor for a cartoon would."
]
} | [] | [] | [
[
"http://en.wikipedia.org/wiki/Microphone#Microphone_polar_patterns"
],
[],
[]
] |
|
2k94g4 | why is the guess who not inducted into the rock n' roll hall of fame? | _URL_0_
I really do think it's a travesty. I think it is because the HOF doesn't typically like Canadians. They also snubbed Steppenwolf. Hopefully this glaring error is rectified soon. | explainlikeimfive | http://www.reddit.com/r/explainlikeimfive/comments/2k94g4/eli5_why_is_the_guess_who_not_inducted_into_the/ | {
"a_id": [
"clj2jqx",
"clj39wq"
],
"score": [
3,
3
],
"text": [
"I don't think it's necessarily their country of origin keeping them out of the HOF.... HOF's are overrated. They aren't a one hit wonder that's for sure. Kind of like Todd Rundgren... under-appreciated. ",
"If you have to link to their wikipedia page, it's kinda indicative of why they're not in the Hall of Fame.\n\nI don't think the HoF discriminates against Canadians. It's not like they're not represented. Neil Young and Rush are the biggest Canadian acts I can think of, Arcade Fire the best modern one."
]
} | [] | [
"http://en.wikipedia.org/wiki/The_Guess_Who"
] | [
[],
[]
] |
Subsets and Splits
No community queries yet
The top public SQL queries from the community will appear here once available.