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lidafy
|
console vs pc
|
Why is it readily available to have a modded or hacked game to enjoy on PC while consoles very rarely have hacked or even modded games?
|
Technology
|
explainlikeimfive
|
{
"a_id": [
"gn2h125",
"gn2h1g4"
],
"text": [
"Not saying it's truly black and white but - two aspects - 1. Console makers have a tremendous amount control of the content used on their systems. Since all PS4s are made by Sony, using Sony software, playing games using Sony's proprietary game network system it's easy for them to a. keep out mods and hacks from being available to its users and b. to detect and deter hacks that do make it through. Hacks/mods can be used to import viruses/malware and also make the game less fun for other users, both serve to drive casual users away from buying more Playstations, so there is an incentive for Sony to guard it's software. 2. PCs are not as centralized, they are cobbled together by parts made by numerous manufacturers, running software that's just as varied. So it's harder to for anyone to act as a controller of the content being played. If people hack a game to the point it's no longer fun for casual users, those users aren't going to suddenly stop buying Motherboard X or monitor B, or even to switch from Steam to whatever bullshit EA offers. So no party has an incentive to play gatekeeper. There is also a selection bias. The overlap of users who know how to create, source, and employ mods, set up their own networks for play, and actively want to be part of the mod making/using community also generally like to build their own rigs and not be burdened by a controlling agency, so they tend to be PC users rather than console users.",
"Because consoles are designed specifically to try and prevent unwanted modifications to their games. Console developers are free to put all sorts of elaborate anti piracy right into the design of the console itself and build their games to match. With a PC, the system itself doesn’t come with that type of dedicated anti cheat, it’s a general use device so devs are on their own to figure out how to secure their pc games."
],
"score": [
10,
4
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"text_urls": [
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|
[
"url"
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[
"url"
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lieyo1
|
why do some bodies store more fat than others?
|
Biology
|
explainlikeimfive
|
{
"a_id": [
"gn2pnvu"
],
"text": [
"Well firstly It depends what you're asking here. Do you mean, why are some people carrying more fat than others? Answer to that comes down to simply consuming more calories than they expend. Not everyone expends the same amount of calories as all bodies are different. However, 2 people at the same height, same age and same activity level will likely expend roughly the same amount of energy as each other. On a genetic level, people store their fat differently, which can visually make someone look bigger (fatter) than someone else at the same weight."
],
"score": [
4
],
"text_urls": [
[]
]
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|
[
"url"
] |
[
"url"
] |
|
lifth4
|
how are we able to have hundreds or thousands of wireless devices sending and receiving signals within range of each other without any of those waves going through the air interfering with one another and corrupting data?
|
Technology
|
explainlikeimfive
|
{
"a_id": [
"gn2vvod",
"gn2ypce"
],
"text": [
"First of all, there's very few cases where there's literally hundreds of thousands of devices attempting to operate on similiar wavelengths in an area similiar to the effective range of those communications. If you think of a worst case scenario like an absolutely packed mega-event, you'd have maybe 60,000 people in a small enough area where they'd be connecting to the same for example, 4G services. In any case, all digital wireless communications protocols have built in error detection and correction methods. In short - every time you DO use anything wireless even if it seems like it's working great, there are corrupted packets that are being discarded. The worse the signal and the noisier the enviornment, the less packets of data that get through unscathed. For the most part, you don't notice the difference because the theoretical maximum bandwidth of 802.11ac is 6.9Gbps - Are you really going to notice a huge difference if it's only working at ~1/7th capacity (1Gbps), especially if your home internet connection isn't even that fast?",
"The premise of the question is not correct because the radio waves do interfere with each other. If you and your neighbours have two separate WiFi networks on the same channel or even a nearby channel for the 2.4 GHz band and devices transmit at the same time can be the case that the access point cant read the packet and it needs to be retransmitted. The interference will not result in data corruption because you have checksum on the data that is transmitted so you can detect if there is transmission error and then the data is retransmitted. Wifi devices do listen to what is transmitted and will not star sending a packet if someone else is transmitting at the same frequency at high enough power. The system works as if you have a group of people that talks. When there is a plus something two people start to talk at the same time but then you stop talking and after a short pause then someone starts to take again but start over again. The result of interference is lower bandwidth, not data corruption. The range of WiFi is quite short by design so a lot of separate networks can be quite close to there and work even if there is a limited number of channels. & #x200B; If you look at mobile phone network then you have a regulates system where each operator has a frequency range the can use. They will then set up the networks so to transmitter direct beside each other do not use the same frequency but you reuse it farther away like [in this picture]( URL_0 ). The cellular network also has a quite short range just because of this reuse of the frequency-time and time again. It is called cellular network because you build it of a lot of small cells. Multiple phones will use the same frequency and communicate with the same tower but you use a clever way to encode the signal so multiple devices can transmit at the same time and the receiver can receive all signal at the same time and get out all the data. It is called CDMA and is a bit like how you can hear two people speaking over each other and still pick out what they say."
],
"score": [
5,
3
],
"text_urls": [
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[
"https://en.wikipedia.org/wiki/Cellular_network#/media/File:Frequency_reuse.svg"
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}
|
[
"url"
] |
[
"url"
] |
|
ligmhn
|
If sunlight takes 8 minutes to reach me then does it mean that at sunset I actually still see the Sun despite that it's already below the horizon and blocked by Earth?
|
Physics
|
explainlikeimfive
|
{
"a_id": [
"gn2zsp9"
],
"text": [
"Yes - at any moment in time you are, in effect, seeing the sun in the position it was in 8+ minutes ago. Same with any moon / planet / star / galaxy in the sky. e.g., yf you're looking at a star that is 10 light years away, then you are seeing it where it was 10 years ago."
],
"score": [
3
],
"text_urls": [
[]
]
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|
[
"url"
] |
[
"url"
] |
|
lih2ch
|
How is a biopsy taken during an endoscopy?
|
Biology
|
explainlikeimfive
|
{
"a_id": [
"gn3bvkw"
],
"text": [
"For biopsies I’ve seen in the past they typically have an attachment to the endoscope that can grab a bit of tissue, tear it off, and then be retracted. Normally a very small amount, not more than the size of a few grains of rice, so it heals up very quickly"
],
"score": [
4
],
"text_urls": [
[]
]
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|
[
"url"
] |
[
"url"
] |
|
lihav2
|
Why do men bald but women don’t?
|
Biology
|
explainlikeimfive
|
{
"a_id": [
"gn33ihb",
"gn38rc8",
"gn38p7g"
],
"text": [
"Testosterone is a hell of a drug. It is responsible for hair growing all over the place and for having men go bald on their scalps. And women do go bald. Just generally slower.",
"Dihydrotestostetone (DHT). It's one of the most potent androgens (sex hormones) implicated in male pattern baldness. There are other dermatologic causes for baldness (in men and women) but the most common cause for men is from DHT and other androgens.",
"There is at least one gene related to hair growth found on the X chromosome. Men only get one copy of this chromosome, thus if that one copy has a less effective hair growth gene that would give rise to baldness, that man will become bald. Women have two x chromosomes, thus both copies would have to have less effective hair growth genes for a woman to become bald."
],
"score": [
13,
3,
3
],
"text_urls": [
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|
[
"url"
] |
[
"url"
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|
lihk5s
|
What exactly is base 8?
|
Mathematics
|
explainlikeimfive
|
{
"a_id": [
"gn35mgk",
"gn35tmu",
"gn5xvtq"
],
"text": [
"we use base 10, which means our number system has 10 digits, 0-9 Base 8 has 8 digits, 0-7 (Base 2 uses 0-1, Base 16 uses 0-F, etc) counting in base 8 goes 0,1,2,3,4,5,6,7,10,11,12,13,14,15,16,17,20... 11 in base 10 means (1 \\* 10\\^1 + 1\\*10\\^0) == 10 + 1 == 11 11 is base 8 means (1\\*8\\^1 + 1\\*8\\^0) == 8 + 1 == 9",
"The regular decimal number system you use is base 10. This is because there are ten different digits that is used to represent numbers 0,1,2,3,4,5,6,7,8,9. If you want to count higher you have to start using two digits, 10,11,12,13, etc. Base 8 only use eight digits instead of ten. So you count 0,1,2,3,4,5,6,7 and then start using two digits 10,11,12, etc. This means that 10 in the decimal system is the same as 12 in base 8 and so on. Base 8 was used in some older computer systems because there is exactly three bits per digit. So it is very easy to convert between base 8 numbers and binary numbers. But base 8 lost out to base 16 which added another six digits by using letters from the alphabet and is exactly four bits per digit.",
"Base 8 is, essentially, what cartoon characters, who have three fingers and a thumb on each hand, would use. Our system is base ten - both hands' worth gets \"chunked\" into the next unit over. Ten ones is a ten, ten tens is a hundred, etc. Theirs would use digits 0,1,2,3,4,5,6, and 7; two hands' worth would be eight, and they'd write that as \"one eight plus none\" the way we write \"one ten plus none\". It would look the same: \"10\". If they wrote \"324\", it would mean 3 sixty-fours, 2 eights, and 4; in base ten those add up to 212. There is a relevant Tom Lehrer song, [New Math]( URL_0 ). --Dave, which actually covers it pretty well"
],
"score": [
15,
4,
3
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"https://www.youtube.com/watch?v=W6OaYPVueW4"
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[
"url"
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[
"url"
] |
|
liho82
|
the difference between affect and effect
|
Other
|
explainlikeimfive
|
{
"a_id": [
"gn360nz",
"gn36bl7"
],
"text": [
"The short version: affect is a verb, effect is a noun. So, the he tornado **affected** citizens within forty miles of Topeka and the **effects** were a number of damaged buildings. Now, to the nuances: - Effect can be a verb meaning 'to bring about' - so you **effect** change in something. - Affect can be a noun meaning a 'feeling or emotion' - so someones **affect** is how they are feeling. - Affect can also be an adjective meaning 'pretentious' - so an **affected** gesture means someone is acting stuck-up",
"“Affect” means “to change something”, example “the nuclear accident affected the health of the citizens nearby negatively”. “Effect” means “the result of something”, example, “the negative effects of the nuclear accident were felt by many citizens nearby”."
],
"score": [
9,
5
],
"text_urls": [
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|
[
"url"
] |
[
"url"
] |
|
liid9k
|
Why does light go into black holes?
|
If light has no mass why does it get sucked into black holes?
|
Technology
|
explainlikeimfive
|
{
"a_id": [
"gn3bgk5",
"gn3bb2x"
],
"text": [
"Gravity doesn't pull on light the same way that it pulls on masses. But gravity isn't just an attraction between masses, it is more properly understood as a warping of spacetime. What this means is that while an outside observer might see light as being bent around a black hole, from the point of view of the light it is always traveling in a straight line as it feels no attractive force from gravity (not having mass). Instead space itself is bent, such that a straight line near the black hole isn't parallel to a straight line a greater distance away. Light is pulled in and trapped by the black hole because space is warped in such a way that there are directions that lead into the black hole but beyond a certain point there are no directions that lead out. This point of no return is called the \"event horizon\".",
"Another way to look at is that light follows the plane of space (this is really simplifiex) and black holes warp that plane. Think of a bed sheet pulled tight across a bed. You roll a golf ball across the middle it it will just go in a straight line. Now, if you place a bowling ball on the sheet, when you roll the golf ball, it will roll closer to the bowling ball becaue of the depression it makes. The \"depression\" in space that black holes make are infinitely deeper than the bowling ball on the bed."
],
"score": [
8,
7
],
"text_urls": [
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|
[
"url"
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[
"url"
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liiyae
|
why can't you make cream by mixing (butter)milk and butter?
|
Butter is made by churning cream, which causes all the fat molecules to clump together (creating butter) and leaves buttermilk as a side product. Following this logic, why can't you make cream again when you combine butter and buttermilk? Or even butter and regular milk for that matter
|
Chemistry
|
explainlikeimfive
|
{
"a_id": [
"gn3elnl",
"gn3f7lg",
"gn3ejh8",
"gn3dxjo"
],
"text": [
"You can make cream with butter and milk. 2 parts whole milk, 1 part melted butter, whip until it forms soft peaks. Ideally, you'd want a stand/hand mixer because it takes quite a lot of whipping.",
"Commercial buttermilk - what you buy at the store - isn't the same as the buttermilk left over from butter churning. Commercial buttermilk is actually skim milk (or similar) that has had bacterial cultures added to it so it _slightly_ ferments. That is what gives it the traditional tangy flavor.",
"You can, but it would be a tremendous pain in the ass. You would need to melt the butter and have the milk warm enough to not firm it all back up. Then you'd need a ton of agitation to emulsify it. Labs use a tool for this using a piston to create cavitations that would most likely do the trick. So yes, you can do it in principle.",
"I think in theory you *could* but you'd need to undo the clumping process. Once the milkfat as been churned to butter, it won't just dissolve back evenly into milk. If you put it through a homogenization process it would essentially turn back into regular, creamy milk."
],
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5,
5,
3
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"text_urls": [
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[
"url"
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[
"url"
] |
lij16t
|
“Bridge may be icy” but why?
|
Does it make a difference if the bridge is over water or a field or etc.? Expand my brain please.
|
Earth Science
|
explainlikeimfive
|
{
"a_id": [
"gn3e9zm",
"gn3e6as"
],
"text": [
"The ground, and the rest of the planet, acts like a giant baked potato. When it's hot (or at least, warmer than the air), for instance when the weather has recently turned cold, it retains its warmth for a while. A bridge is like a small slice of that potato - it cools much faster. So, while the air may be cold enough to freeze water, the bridge will cool to that temperature faster than the normal ground. This happens because it has much less material to retain heat, while it is exposed on all sides to the cold air.",
"On regular roads, the Earth is insulating the road, which does a lot to reduce ice build up. Because air can pass under the bridge, they're a lot colder than the roads they connect to. This means the bridge might be icy while the road is not."
],
"score": [
14,
9
],
"text_urls": [
[],
[]
]
}
|
[
"url"
] |
[
"url"
] |
lij2d9
|
How does our brain know we forgot something but not exactly what?
|
Biology
|
explainlikeimfive
|
{
"a_id": [
"gn4a7m4"
],
"text": [
"Memory is based on connections: everything from emotions to images, touch even smell. But those connections are only as good as they are used. So if you are distracted when your brain tries to make those connections, haven't used that memory in a while or there is some other factor (e.g. you went to the bar and had a little too much) - the connection is broken. But not completely. The \"tip of the tongue \" is when there is enough of the connection so that you \"know\" there is a memory but the specifics are missing."
],
"score": [
16
],
"text_urls": [
[]
]
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|
[
"url"
] |
[
"url"
] |
|
lij6bf
|
What causes the falling sensation that happens when we’re asleep?
|
Biology
|
explainlikeimfive
|
{
"a_id": [
"gn3hbx1",
"gn3jabi"
],
"text": [
"From what I understand, it's when your body is more tired than your brain. Your muscles relax and your brain freaks out and thinks you're free falling.",
"It is called a hypnic jerk. It is when there is a brief sudden involuntary contractions of muscles while falling asleep. It doesn't always have to accompany a falling sensation but it sometimes does. Up to 90% of people have experience it and 10% experience it daily. There are potential causes like anxiety, stress, strenuous activity in the evening, stimulates like caffeine or nicotine. But most are usually random in healthy people. We don't exactly know why they occur. There are some purposed theories but none have been fully accepted!"
],
"score": [
9,
9
],
"text_urls": [
[],
[]
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|
[
"url"
] |
[
"url"
] |
|
lijq9y
|
Bayesian Reasoning
|
Other
|
explainlikeimfive
|
{
"a_id": [
"gn3ril1",
"gn3o66m",
"gn4pixb"
],
"text": [
"Bayesian statistics is all about making a prediction and updating it as you go, or about figuring out how likely something is given that something else is true or false. For example, you have two coins in a bag. One is a regular coin with a heads and a tails. The other is a trick coin with two heads. You pull one coin out of the bag. How likely is it that you picked the real coin? Now, you flip it, and it comes up heads. *Now* how likely is it that you picked the real coin? Say you flip the same coin again and get heads again. Does the likelihood that you picked the real coin change? Another way to think of it is like a game of Marco Polo. In case you're not familiar, one person is blindfolded. They should \"Marco\" and the other person (or people) reply \"Polo.\" For now, let's assume you and a friend are playing in a large room. You're blindfolded, and your friend isn't allowed to move. You stand in the centre of the room and shout. You hear your friend off to your left. But you're not sure if they're in front or behind you, or how far left. So you walk diagonally forwards to the left, half way to the corner of the room. Now you shout again. When your friend replies, you can tell if they're still to your left (i.e. close to the wall) or if they're now on your right (i.e. between where you are and the middle). You can also tell if they're closer to you or further away, i.e. in the front of back half of the room. You keep moving about and shouting. Each time you build up a better picture of where your friend is. Each of these turns wouldn't be very helpful by themselves, but together they give you a lot of information. One of the main fields where Bayesian analysis gets used (whether consciously or not) is in medicine. Say there's a really rare illness that maybe 1/100,000 people have. One of the symptoms is a cough. This means is you pick someone off the street at random, there's only a 1/100,000 chance they have it. Now, you develop a cough. You go to the Drs and mention this condition. Is it likely that you have it? Probably not. It's rare, and a cough is a common symptom of a lot of stuff. But you have a slightly higher than 1/100,000 chance. Now, let's say you are ginger, and this illness is more common amongst ginger people. Well, the chances you've got it are higher. Also, there happens to be an outbreak in your area. It's now beginning to look much more likely that you have this condition. So, each of these fact separately might make it seem unlikely that you had this illness. But together, we get a more accurate picture of what's going on.",
"There are two \"interpretations\" of statistics. One that sees probabilities as something thats inherent to an event (e.g. you roll a dice, chance to get a 6 is 1/6, thats inherent to rolling dice.) The other reasoning sees probability as something depending on the observer - e.g you look a lt a cloud and guess that its 50/50 that it'll rain tomorow. Then you check some satelite footage, get good data, and find out that its actually 90%. Nothing you did changed whether it actually rains or not, just your information and thus the probabilities ascribed by you changed. Bayesian reasoning refers to the latter. Bayes created a bunch of equations to deal with changing information and how they affect probabilities, that nowadays are extremely important in science and engineering.",
"Another way of thinking of at least some uses of it is to take an answer to the wrong question and turn it into an answer to the question you actually want an answer to. This often comes up with medical testing, where you can have a test that's very accurate but most of the positive results are false. Say you have a test for Zoidberg's Disease that's 95% accurate. This is the answer to the wrong question -- that means that if you have Zoidberg's Disease, there's a 95% chance that the test will be positive, and if you don't have it, there's a 95% chance the test will be negative. This isn't any help to you, the patient, because if you knew you have Zoidberg's Disease you wouldn't go getting a test for it. What you want to know is: my test came back positive, what does that mean for me? And the answer will depend on how common Zoidberg's Disease is. Let's say it's rare, only 2% of people have it. So in our city of 100,000 people: 98000 don't gots it 2000 gots it And our test is 95% accurate, so: * 95% of the 98000, or 91300, don't gots it and get a negative result * 4900 out of the 98000 don't gots it but get a positive result * 95% of the 2000, or 1900, gots it and get a positive result * 100 of the 2000 gots it and get a negative result Put that together, and how many people get a positive result? 6800. But only 1900 of them actually have Zoidberg's Disease, so only 28% of positive results are correct even though 95% of total test outcomes are correct."
],
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3
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[
"url"
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[
"url"
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|
lijtbk
|
How do we know what part of the DNA chain does something?
|
We can't remove the DNA part, can't we?
|
Biology
|
explainlikeimfive
|
{
"a_id": [
"gn3kt20",
"gn47uj1"
],
"text": [
"DNA is read in 3 letter chunks called \"Codons\" most of these represent specific amino acids that will be used to build proteins. However, There are a couple special \"Start Codons\" that tell your cells \"Hey, this is the start of a gene, start reading here.\" Correspondingly, there are also \"Stop Codons\" that tell your cells where the end of a gene is. So, scientists can scan through DNA looking for start and stop codons and assume that anything in between those must be part of a gene. Now, it turns out that a large majority of DNA isn't a part of any gene, but that's not to say that it doesn't do *anything*. It can contain regions that make certain genes more or less likely to be read, it can be structural, helping the DNA coil correctly to fit into the cell, or it can help stabilize other cellular machinery. Furthermore, having a certain amount of \"extra\" DNA around is good for evolution, because a mutation in an important gene might kill you, whereas a mutation in a section of DNA that's not being used will probably have no effect. But, if some of that unused DNA gradually turns into something useful, you can create new genes without breaking old ones.",
"You can absolutely remove parts of DNA in animals. Gene knock outs or knock ins are common genetic manipulations. You can basically add or delete any gene you want from lab animals and see how the function changes. Of course some of these genes are essential for life and knocking them out would not produce a viable subject. As mentioned elsewhere, GWAS is commonly used now that we have sequenced the human genome and can look for genetic difference among groups of people."
],
"score": [
8,
3
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"text_urls": [
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|
[
"url"
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[
"url"
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lijwo9
|
Why do some spicy foods hit hard and fade quickly (wasabi), while others start subtle but build up (flaming hot Cheetos), and others hit hard, stay a long time, and ruin my sleep (lamb vindaloo)?
|
Chemistry
|
explainlikeimfive
|
{
"a_id": [
"gn3k089",
"gn3jvh9",
"gn3lhwy"
],
"text": [
"Its worth pointing out that Wasabi (and horseradish) contains a different spicy chemical than chilies. That's why you feel wasabi up in your nose, that chemical evaporates much more easily and you end up breathing it out, whereas the chemical that's in chilies is an oily liquid that doesn't really evaporate. These two chemicals also act on different receptors in our mouths, creating different sensations.",
"Because they contain different molecules with the same effect Jalapenos have capsaicin which is Lipophilic Wasaby have isoticinates which on the contrary are not soluble in fats",
"It's all dependent on the rate at which the chemicals that cause the spiciness break down. Capsaicin is oil-based, so it takes a while to break down, and the more capsaicin you eat the longer it takes your body to deal with. Allyl isothiocynate (which causes the pungency in wasabi, horseradish, and mustard) is *not* an oil, and tends to break apart much faster, hence why you end up with a quick hit of flavor that doesn't last very long, and which can actually be washed away relatively easily."
],
"score": [
10,
3,
3
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"text_urls": [
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[
"url"
] |
[
"url"
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|
lik76n
|
What is nitro cold brew and how is it different from regular cold brew?
|
Other
|
explainlikeimfive
|
{
"a_id": [
"gn3m4kc",
"gn3m91m"
],
"text": [
"Regular Cold Brew is made with ground coffee and cold water soaking in the refrigerator for 12 to 24 hours. It would be filtered before serving. Nitro Cold Brew is regular Cold Brew being served from a tap that uses Nitrogen to pressurize the keg and lines. Nitrogen makes much smaller bubbles than CO2. This gives a Nitro Cold Brew a foamy layer of bubbles at the top.",
"Nitro cold brew and regular cold brew coffee start out the same. Nitro cold brew adds nitrogen much like soda has carbon dioxide added. Nitrogen has smaller bubbles than CO2 resulting in a creamier mouth feel. [Nitro Cold Brew - Wikipedia]( URL_0 )"
],
"score": [
4,
3
],
"text_urls": [
[],
[
"https://en.m.wikipedia.org/wiki/Nitro_cold_brew_coffee"
]
]
}
|
[
"url"
] |
[
"url"
] |
|
likc1j
|
Why is commercial air travel still the same speed it was 60 years ago? And will it ever change?
|
Technology
|
explainlikeimfive
|
{
"a_id": [
"gn3m0ad",
"gn3nqsk",
"gn3odmq",
"gn3m3o9",
"gn3m4h3",
"gn7gev1"
],
"text": [
"It did get faster, we had the Concorde, which was super sonic and heinously expensive to operate. That’s really what it is. We’ve optimized aircraft from a cost vs speed perspective. Can we go faster? Hell yea. Is it cost effective or affordable? Not really. Source: am an aerospace engineer",
"[Because transonic drag (Mach 0.8-1.2) is awful]( URL_0 ) Around 80% the speed of sound the drag on the plane starts to skyrocket, going from 80% to 90% can be a 3x increase in drag which results in a 3x increase in fuel consumption which results in a massive increase in ticket cost. Once you get beyond about Mach 1.2 though drag starts to drop off. This region between Mach 0.8 and Mach 1.2 is the transonic region and its when some of the airflow is supersonic (pinch points and tight curves on the plane) while others parts are subsonic and it creates this real mess. This is why planes either fly well under Mach 1 or well over. Jet airliners have been running in the Mach 0.75-0.85 range for over 60 years now, that's as high as they can practical go without breaking the sound barrier which is a no-no over land, that's why they've instead been focused on fuel efficiency to reduce running costs There is research into Quiet Supersonic jets but its still quite experimental and a few decades off. Until we can get rid of the damaging sonic boom overland flights have a pretty firm limit at Mach 0.85",
"The problem is that we started to approach the sonic barrier. The effects of the speed of sound starts to show itself in some areas at around 80% of the speed of sound. This is because the air needs to move around the aircraft body and the wings and may therefore have to go faster then the speed of sound in certain places. The problem is that when you start getting these areas of air going faster then the speed of sound you start getting a layer of high pressure air clumping up in front of the aircraft. At lower speeds this high pressure air will be able to move forward away from the aircraft but not when you start getting towards the speed of sound. The problem is that this high pressure air is pushing the aircraft back. That creates a lot more drag then normal flight. You therefore need a lot more power and use a lot more fuel to fly closer to the speed of sound. And is there anything commercial air travel does not like it is to use more money on fuel. At around 80% the speed of sound is usually the most fuel efficient speed. Fly slower and you have to spend more fuel because the flight is longer and fly faster and you have to spend more fuel because of the increased drag. There are a few aircraft that is designed to fly faster. Of course the Concorde was designed to fly faster then the speed of sound. By going faster then the speed of sound you get rid of a lot of the issues with drag however you still need to use about twice the fuel in normal cruise and a lot more fuel punching through the sound barrier. So the Concorde was very expensive and required big fuel tanks compared to its small cabin. The price was not really its problem as its clients were not looking at the price themselves, however the cabin size was a problem. But there are a few private jets which can go faster then most commercial airliners. There are several that goes about 90% the speed of sound and a few planned ones designed to go supersonic. But these do require people who are rich enough to want to spend the massive amounts of money on fuel at these speeds.",
"Travelling faster requires a lot more energy and that means more fuel, it is possible to build an aircraft surpassing that of Concorde, but it would be expensive to build an operate and the demand for very fast aircraft isn't there.",
"> Why is commercial air travel still the same speed it was 60 years ago? And will it ever change? Supersonic commercial flight was [tried out]( URL_0 ), didn't prove to be in enough popular demand to be deemed profitable and was abandoned again.",
"One of the reasons is simply diminishing returns. Crossing the ocean in an old sailing ship could take months. Crossing the ocean in a steamship took a week -- saves the traveler 4-5 weeks of travel time. Crossing the ocean in a plane takes hours -- still saves the traveler a week or more. Crossing the ocean in a supersonic plane is insanely expensive -- only saves a few hours. We reached a point where the time saved isn't worth the extra expense, at least for most people."
],
"score": [
37,
11,
11,
6,
3,
3
],
"text_urls": [
[],
[
"https://upload.wikimedia.org/wikipedia/commons/0/0e/Qualitive_variation_of_cd_with_mach_number.png"
],
[],
[],
[
"https://en.wikipedia.org/wiki/Concorde"
],
[]
]
}
|
[
"url"
] |
[
"url"
] |
|
liku2o
|
How come it is easy to laugh at flat earthers or zodiac sign believers but not catholics?
|
Other
|
explainlikeimfive
|
{
"a_id": [
"gn3sn3v"
],
"text": [
"Religions and faiths make very different claims from flat earthers. Flat earthers make claims about the physical state of the world, the natural order. These claims are scientific in nature, and so can be rejected by the scientific process and scientific experiments. We can make repeatable observations that show these claims are not the case. On the other hand, faiths make claims about the *super*natural. By definition, this is beyond the natural world, and so cannot be studied simply by scientific methods. Exactly what evidence is used to back up these claims depends on who is making the claim and what specific religion, faith, or denomination we're discussing, but they may be founded in historical events and/or personal experience. Different types of proof are required for different things. For example, science relies on repeating the same thing over and over again and getting the same result. But in maths, that method of \"proof\" is now seen to be woefully inaccurate. There are plenty of \"patterns\" that you can spot in numbers that last for tens, hundreds, thousands or millions of terms, but which we know break at some point. There are other things which mathematicians believe to be true, but we're not sure of yet as they haven't been mathematically proven. Indeed, one could ask why we use the scientific method. It's a bit of a circular argument. We use it because it has worked well for us so far. But There's nothing concrete to say that that will always be the case."
],
"score": [
4
],
"text_urls": [
[]
]
}
|
[
"url"
] |
[
"url"
] |
|
likx37
|
How did people copy something from a VHS/cassette tape since they're physical..?
|
Technology
|
explainlikeimfive
|
{
"a_id": [
"gn3q6rj",
"gn3qhkf",
"gn3xorm",
"gn4441h",
"gn3rg4p"
],
"text": [
"All digital files are copied from an original. All analog files are copied from an original. The original file will usually have a few backup copies made for redundancy in case it is damaged, but it will also be handled with care. Even in the digital age, you will occasionally hear that a company has lost a shitload of money because they have accidentally lost some important data.",
"You got it right, there is a MASTER copy out there somewhere and they would set it up in machines that would copy the master to thousands of other tapes at the same time. Technically they would use the Master-master to create Master-copies and then make the mass copies from the Master-copy, all to protect the original Master-Master. They protected the heck out of that master because if they lost it, there could be problems. In a few famous cases the masters of various albums, TV shows, movies, have been lost or destroyed and those are simply.. gone. An entire season of Dr. Who from back in the day is lost because the studio recorded over the master with a soccer match I believe, although I think they've found a few random bits. Interesting fact, in some cases the master is a higher quality than duplicates they produced at the time. For example old movies filmed with actual film. When they make 4k HD versions of these films now they can go back to the original master and get the increased definition straight from the source.",
"There were special machines used for duplicating VHS tapes. They used thermal magnetic duplication and could copy a tape at up to 900x faster than real time. You need a machine like this one here, plus a few others: URL_0 First you have one machine that you feel the video/audio signal into and it creates the master. You load the master into the 2nd machine, and it spits out recorded video tape at high speed. A 3rd machine takes the newly recorded tape and loads it into the video cassettes. 20 years ago, expect to pay about $500,000 for a complete setup.",
"You may find [this]( URL_0 ) useful. It's for audio tapes but it's similar for VHS. TL;DR: They're recorded to multiple tapes simultaneously onto HUGE reels at faster than normal speed and then chopped up.",
"There is a “master copy” of everything. There’s an original. Copies are made, and every copy is just a duplicate of the original. There are often a bunch of 1st copy ones saved in case something happens to the “master”. You could, once upon a time, just connect two VHS machines together and just play from one and record onto another. This wasn’t perfect and the copy wouldn’t be as good. It’d be barely noticeable. But you wouldn’t have the types of quality machinery than they do in factories where copies are made en masse. These days things are all digital so you just burn another one onto a disc. Records are actually all analogue still, so records are copied - from record to record. Decent records (vinyl discs) shouldn’t ever be burned from a digital file."
],
"score": [
7,
6,
5,
3,
3
],
"text_urls": [
[],
[],
[
"http://www.otari.com/support/vintage/t710/index.html"
],
[
"https://www.youtube.com/watch?v=EyGYp9UzXbg"
],
[]
]
}
|
[
"url"
] |
[
"url"
] |
|
lil7sp
|
How do bits in a computer become meaningful to human beings?
|
Technology
|
explainlikeimfive
|
{
"a_id": [
"gn3rfv0"
],
"text": [
"Bits aren't meaningful. What they produce is meaningful. If I use the bits in a computer to generate a picture of my wife on a monitor, then I will value the computer and its \"bits\" for being able to provide me something valuable to me. I don't care about the bits themselves. No one does. They are only tools in a process that creates things of value."
],
"score": [
5
],
"text_urls": [
[]
]
}
|
[
"url"
] |
[
"url"
] |
|
lilr3b
|
Why do people "dance" when they need to pee really bad?
|
Other
|
explainlikeimfive
|
{
"a_id": [
"gn3ulwg"
],
"text": [
"They are trying to shuffle and relaxe the muscles around their bladder, so that it can hold just a little bit more"
],
"score": [
4
],
"text_urls": [
[]
]
}
|
[
"url"
] |
[
"url"
] |
|
lilwkz
|
Why does your chest hurt and its hard to breathe if youre out of shape and do cardio?
|
Biology
|
explainlikeimfive
|
{
"a_id": [
"gn48vji"
],
"text": [
"Because your heart is a muscular organ and subject to the same atrophy that your arms and legs are. Much for the same reason if you work up to lifting 100lb weights and then suddenly stop exercising for 5 years, you're not likely to lift that same weight when you start again."
],
"score": [
3
],
"text_urls": [
[]
]
}
|
[
"url"
] |
[
"url"
] |
|
lilzwn
|
Why do we feel euphoria when we pull an all-nighter?
|
Biology
|
explainlikeimfive
|
{
"a_id": [
"gn4a1y6"
],
"text": [
"So remember that the human body is like a machine- it’s built with different parts and systems for different things. But most good machines have ways of at keeping running when one or two things go wrong- think of them as failsafes. Human bodies have a lot of these systems, all with the stated goal of keeping you alive. They get triggered when something goes wrong- usually when you are either in danger, or a basic need is not getting met (like food or water). Let’s focus on that second one- when a basic need is not met, the body assumes you are in some sort of danger, so it “activates the fail safe” to keep you safe. When you lack sleep, your body doesn’t necessarily know why. But it just knows that you are not getting something essential, so it assumes you’re in danger. You could stay up all night watching TV, or be running from terrifying animals for a long time with no rest, and your body wouldn’t really know the difference. So, with no sleep, your body does what it can to a). Keep you alive, and b). Keep you moving. So in some ways it gives you a strong positive feeling to keep you moving, because the body thinks you need to find a safe place to sleep. In other ways, it moves oxygen and other important things from your brain to the rest of your body, because those parts need it to keep going. This has a side effect of feeling euphoric. TLDR: Pull an all nighter, and your body will assume you’re in a desperate situation. So it makes you feel good and light so you have the best chance of surviving, in the short term."
],
"score": [
7
],
"text_urls": [
[]
]
}
|
[
"url"
] |
[
"url"
] |
|
limcg0
|
What’s special/different about 5G?
|
Technology
|
explainlikeimfive
|
{
"a_id": [
"gn40oir",
"gn41vg3"
],
"text": [
"Videos playing faster isn’t really the point (though it’s a minor point). The main point is that 5G can handle more users in crowded spaces like concerts and sporting events. (In the beforetimes, crowded spaces were when our phones stopped working even though we had service because towers were overwhelmed.) It will also be able to provide short distance super high speeds. So, maybe you have a park that gets 5G millimeter wave (which is what it’s called). Eventually, that tech will roll out to more places than just a few parks. Adding bandwidth enables new capabilities. There’s much bigger files out there than YouTube videos. Maybe people want to use AR in the park or businesses want to transmit high quality 3D scans of construction work. Streaming video games and other programs will require lots of bandwidth.",
"Using a higher frequency of radio waves lets you pack more data into the signal. Imagine sending a message with beeps, but not like Morse code. Instead, there's a constant one beep every second. You can *modulate* your beeps to send a beep every half second instead. So, \"beep beep beep\" would be 000 and \"beep beepbeepbeepbeep\" would be 011, and so on. This limits your data speed to one bit (0 or 1) per second, since you have to wait a full second each time to know if it's a 0 or 1. If you instead increase the speed to ten beeps per second for a 0 and twenty for a 1, you can obviously send data way faster! Similarly, the radio signal is a wave that goes at a certain frequency, and you can modulate the frequency to increase it or decrease it slightly to indicate a 0 or 1. A higher frequency means more data. One problem with this is that if your \"beeps\" are too rapid, and the difference between the two speeds is too small, you might not be able to hear the difference between them. Similarly, a higher frequency is a bit harder for the receiver to decipher. That's not a big problem, though, and modern technology has advanced enough for devices to be able to figure it out. The other big problem is that for physics reasons higher frequencies don't travel as far. They get absorbed better by stuff, especially water, which the atmosphere is full of. Walls and trees aren't helping, either. To overcome that, you need more towers that are closer together. That becomes very expensive very quickly. Like the early days of cell phone coverage, some places just aren't going to get 5G. And in fact, this is the same reason that some places even in the US *still* don't have 4G or sometimes even 3G coverage. The other way to solve this problem is to make the receiver more sensitive. That has its own problem - it will also pick up more radio noise, so it needs to be able to filter the noise and find the signal you're trying to pick up. As you've probably picked up by now, 5G uses a higher radio frequency so it has a higher bandwidth than 4G - *much* higher bandwidth. Phone technology is good enough now to be able to detect a weaker signal and filter out the noise. Service providers also have more existing infrastructure to add antennas and are willing to invest to build the additional infrastructure needed so there's enough coverage. With these advances, 5G could give the kind of internet speeds you normally only see with on a decent connection at home."
],
"score": [
3,
3
],
"text_urls": [
[],
[]
]
}
|
[
"url"
] |
[
"url"
] |
|
limiym
|
How do satellites not fall back to Earth due to gravity if they are not traveling at escape velocity?
|
Physics
|
explainlikeimfive
|
{
"a_id": [
"gn3zc43",
"gn3zz8c"
],
"text": [
"Satellites *are* falling back toward Earth due to gravity. But because of their sideways velocity, they keep missing it. Escape velocity is the velocity and object needs to travel away from a gravitational source such that it can continue forever away from that source without needing additional boosts to its velocity. Literally, the velocity needed to escape the effect of its gravitational pull. Satellites aren't meant to escape Earth's gravity, but rather to come into equilibrium with it.",
"Escape velocity is not the speed required to orbit the Earth, it is the speed required to *escape* from orbit and leave the Earth behind forever. There's a range of speeds in between the minimum speed for Low Earth Orbit (about 7,800 km/hr) and Earth escape velocity (about 11,000 km/hr, from LEO)."
],
"score": [
21,
6
],
"text_urls": [
[],
[]
]
}
|
[
"url"
] |
[
"url"
] |
|
limqai
|
How did the Wellerman find whaling ships to meet up with?
|
I looked up the meaning behind the sea shanti lyrics "soon may the Wellerman come" and learned that it referred to supply ships which brought provisions to whaling vessels. My question is: How did these supply ships find the whaling vessels? Did they just agree to meet at a certain port before setting sail? I find it hard to imagine that they had the technology to reliably find a ship somewhere in the middle of the ocean without modern navigation techniques.
|
Other
|
explainlikeimfive
|
{
"a_id": [
"gn40ooo",
"gn4fq2i"
],
"text": [
"Whalers would render the blubber into oil and that produced a lot of smoke that could be seen far away. I can suggest you watch \"Master and Commander\", where they disguise their ship as a whaler to lure in the enemy.",
"> I find it hard to imagine that they had the technology to reliably find a ship somewhere in the middle of the ocean without modern navigation techniques. With a good sextant, a clear night, and decent astronomical tables, a competent navigator could put a ship within half a mile of any pre-arranged coordinates; close enough for a visual sighting."
],
"score": [
11,
7
],
"text_urls": [
[],
[]
]
}
|
[
"url"
] |
[
"url"
] |
limvfw
|
Why would a bank lend out mortgages when rates are so low?
|
Aren't banks trying to make money like every other business? If ROI on mortgages is only 2.5%, but market investments are 7%+, why do banks lend out mortgages at all? Is it a low risk thing? How do banks decide how much of their portfolio goes toward lending out mortgages?
|
Economics
|
explainlikeimfive
|
{
"a_id": [
"gn44b2b",
"gn4c3ff"
],
"text": [
"It has to do with balancing risk and return. Mortgages are backed by the government and by an asset that typically appreciates in value. Think of it as eating the salad at lunch to compensate for the ice cream for dessert later (the higher but inconsistent market returns).",
"To qualify for a low interest home loan, the buyer needs to have a reasonably solid credit score, put a significant down payment on the loan, and carry insurance on the property. If the loan goes into default, the bank can foreclose on the property for auction. If the property is seriously damaged or destroyed, the insurance company takes the loss. The only real risk the lender faces on any given loan is if the debtor defaults *and* there is a significant decline in the fair market value of the property. Take that single low risk loan, bundle it with 10,000 other low risk loans, scattered across the country and at varying stages of maturity, and you have an investment product that is very secure with almost no risk of loosing value for your investors. As an individual investor, if you have money you aren't using but you can't risk loosing (e.g. your emergency fund), and you want some protection against inflation, this is a fairly good place to put some of it. Over a long enough timeline, the broad stock market will almost certainly outperform a mortgage backed security, but in any given moment you may face significant loss of value. If we're talking about that emergency fund, when the next recession comes around you can't afford to have it loose value just as you are most likely to loose your job ."
],
"score": [
6,
6
],
"text_urls": [
[],
[]
]
}
|
[
"url"
] |
[
"url"
] |
lin183
|
Can someone explain how a small country like the Netherlands has a stock of Foreign Direct Investment abroad that is 5,809,000,000,000, and ranked second in the world after the European Union? And what does this mean, is this the total value of assets by Dutch companies abroad? I'm fascinated!
|
Economics
|
explainlikeimfive
|
{
"a_id": [
"gn42jtz",
"gn43s3q"
],
"text": [
"It's because of multinationals playing tax games, apparently. [ URL_0 ]( URL_0 ) > Not surprisingly, the huge FDI from the Netherlands also has a lot to do with tax planning. Most of it consists of investments abroad that foreign multinationals own via Dutch holdings. Only a fifth consists of real Dutch investments.",
"So we first have to understand what Foreign Direct Investment (FDI) is. This is the dollar amount of foreign companies/people directly investing in companies in the Netherlands. There are two reasons that the Netherlands ranks so high. First is that many of the bigger companies in the Netherlands are actually traded on stock exchanges in the EU. This artificially raises their FDI. The other aspect is that the Netherlands has made it very attractive for people in other countries to invest. They have almost no financial regulations that would restrict it, and great tax rates to encourage it."
],
"score": [
17,
5
],
"text_urls": [
[
"https://www.taxjustice.net/2014/11/10/netherlands-worlds-largest-source-fdi/"
],
[]
]
}
|
[
"url"
] |
[
"url"
] |
|
lin29p
|
What is inflation and what does it mean when people say the currency in Venezuela is worthless?
|
Economics
|
explainlikeimfive
|
{
"a_id": [
"gn44jdm",
"gn44x20",
"gn45k8j"
],
"text": [
"Inflation is generally when money is worth less than what it was. Almost all economies inflate. Hence why $1 back in the day was worth a hundred today. In the U.S. our average inflation per year has been around 3%. Meaning every year our dollar is worth 2-3% less than it was the previous year. Most government jobs see a raise of 4-6% per year to compensate for increased inflation as well as increased experience in that job. The reason inflation exists is that more money enters circulation than the money that leaves circulation. If there is only $100 in a town of 10 people, each dollar would be worth a lot. You would have to pay pennies and your entire livelihood would be between $2-5 with one person most likely holding onto $30-50. If that town were to print more money it wouldn't necessarily mean anyone would be getting paid more, it would just devalue their money. There would still be 10 people in a town fighting to survive. $2-5 would just be $20,000-50,000 with one person who has $300,000-500,000. When you get to other countries they tend to have a value they control through trading. This used to be tracked in gold. Every country could make whatever currency with whatever value but their amount was determined by the amount of gold they had. If they wanted to increase their country's value they would trade something to another country to get more gold. These days it is done with GDP, exports and Loans mostly. It doesn't really work that way anymore but I like explaining it that way because it's easier to explain as. Venezuela has a lot of currency, but very little gold. So other countries don't respect their currency so it is devalued to the point that if you want to order something that is $50 in the U.S. it would require about $500 in Venezuelan currency. That isn't the most inflated currency in the world, but Venezuela is often a hot topic in politics because of their current governing style. Inflation isn't always a bad thing though. If countries compensates correctly, you can inflate all you want and still have strong economies. Sweden for example has more millionaires and billionaires per capita than most countries, including the U.S. (using U.S. currency as an indicator) and their currency is worth about an 8th of the U.S. Dollar. Meaning if you want $100 in the U.S. you would need to earn $800 in Sweden to have $100 in the U.S. Which seems like a lot more work, yet Swedish people get paid significantly hire in the middle income area than those in the U.S. I know this was a longer text, but you asked two questions, explaining inflation alone wasn't enough in my opinion.",
"So, imagine you are making juice using a can of frozen concentrate. You put in the tin of juice mix, and 3 tins worth of water. That juice you just made is the economy. The concentrate is the actual value of your economy, and the water you added is the dollars you have printed to represent that value. Now imagine you need more juice... so you add more water. Sure, you have more juice, but it's watered down; it's less good. Same thing when a country needs to pay a debt so it prints more money, it waters down how much that money is actually worth because the underlying value didn't change, just how thin it was spread out. That's basically what happens when a country's currency holds no value. Either the country has printed more money than it is worth, or the value of that country has dropped (because trade partners see them as risky to trade with for a variety of reasons).",
"Inflation itself is just the term to describe the worth of money decreases over time. Contrary to that we have deflation which means the value increases. Inflation can have many reasons and is induced by the EU and US to stimulate the economy at a low rate. This can be done by giving out new money into the economy. There is a fixed amount of value in any country and a fixed amount of money, so basically you could see how much worth something is by calculating what part it is of the economy and then taking that part of the money. For example, the whole economy of Banania is 100 Bananas and there is a total of 2000 Banana Dollars. 1 Banana is 1/100 of the whole economy and 1/100 of 2000 Banana Dollars is 20, so one Banana is worth 20 Banana Dollars in Banania. Now the Government decides to print 2000 more Banana Dollars. The Bana is still 1/100 of the economy, but now the Banana is worth 40 Banana Dollars. You now need double the money to buy a Banana. & #x200B; In Venezuela something similar happened, in addition, inflation causes more inflation by other factors, like people wanting to spend their money now instead of waiting for it to become worth less, which makes money even less valuable since there are more buyers for the same good. These extreme cases are called Hyperinflation, they spiral out of control and can devalue money to a fraction of it's worth in months."
],
"score": [
24,
5,
3
],
"text_urls": [
[],
[],
[]
]
}
|
[
"url"
] |
[
"url"
] |
|
linarx
|
What’s the meteorological processes that made the current winter storm so particularly bad?
|
Earth Science
|
explainlikeimfive
|
{
"a_id": [
"gn568ee"
],
"text": [
"At the top of the planet there’s a circulating rope of air called the Jet Stream that keeps the super cold Arctic air up in the North Pole. Now if the jet stream happens to get an influx of energy or some kind of disturbance, it will stretch out kind of like a spinning rubber band does from centripetal force. When it does this, it kind of droops down towards the middle of the planet so now the barrier that stops the Arctic air from going south is no longer in northern Canada - it’s in like Kansas. This is the simplified version. Interestingly climate change is expected to cause harsher winters due to this effect."
],
"score": [
4
],
"text_urls": [
[]
]
}
|
[
"url"
] |
[
"url"
] |
|
liobzn
|
Why does the human visual field seem to disappear when staring at something for an extended period of time without blinking the eyes?
|
Biology
|
explainlikeimfive
|
{
"a_id": [
"gn4asi3"
],
"text": [
"This is called adaptation. The nerve cells respond best to changes, it’s the same kind of thing when you put a napkin or something light on your hand, you will feel it at first but then you get used to it. Why do we have this evolved? Things that are moving and changing would probably kill us quicker than something that doesn’t. It makes sense that we are tuned to notice changes around us"
],
"score": [
3
],
"text_urls": [
[]
]
}
|
[
"url"
] |
[
"url"
] |
|
liot0h
|
why do Reese’s peanut butter hearts taste vaguely different from Reese’s peanut butter cups?
|
Other
|
explainlikeimfive
|
{
"a_id": [
"gn4eppi"
],
"text": [
"Because there's a greater peanut butter to chocolate ratio. I personally like the Easter eggs myself."
],
"score": [
20
],
"text_urls": [
[]
]
}
|
[
"url"
] |
[
"url"
] |
|
liou7e
|
What creates freezing rain conditions vs. snow?
|
Hello from Central TX! A few weeks ago, we got tons of pillowy, perfect snow for the 1st time in my life. This weekend, we are getting dangerous freezing rain. What conditions create freezing rain instead of wonderful snow?
|
Physics
|
explainlikeimfive
|
{
"a_id": [
"gn4d0e6",
"gn4gccc",
"gn4hrt0"
],
"text": [
"Freezing rain is caused when snow falls through a large pocket of warm air on the way down. This melts the ice crystals a bit, but when they return to colder air they'll freeze up again. Sleet is caused the same way, just with a smaller pocket of warm air.",
"Freezing rain is when rain is supercooled so that it freezes immediately when it his a surface. Everything gets coated with a layer of ice. Not nearly as much fun as snow :-)",
"The lower atmosphere changes temperature rapidly with height, sometimes it’ll act as a “sandwich” where there’s two very cold layers with a warm layer in the middle. We call this a “warm nose”. How deep it is changes the precipitation type. If it extends almost to the ground then you end up with frozen rain because the snow doesn’t have time to refreeze after it melts in the warm nose, however the ground it still below freezing so the water freezes as soon as it comes into contact with a surface. If the warm nose is shallow then sometimes the snow doesn’t melt fully and you get sleet or slushy snow on the ground."
],
"score": [
13,
4,
3
],
"text_urls": [
[],
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|
[
"url"
] |
[
"url"
] |
lip1c5
|
Why is it when someone opens the door to a 500c (932f) degree oven, the rush of hot air doesn't burn them?
|
Physics
|
explainlikeimfive
|
{
"a_id": [
"gn4dot4",
"gn4de4h",
"gn4gv4e"
],
"text": [
"Where the hell does a 900F oven exist? That's a kiln, not an oven.",
"Air is a relatively poor medium for transferring heat. Direct contact with metal, or submerging in water or something would be much quicker. That is what will burn in the short term, high heat over a short time. Since air doesn’t transfer heat to our face very quickly, it doesn’t burn us much. Given enough time it certainly would, but a few moments will just be uncomfortable.",
"Air is a poor conductor of heat. I wouldn’t recommend it, but you can stick your hand into a 120 C oven for a few seconds and be totally fine whereas putting your hand into 100 C (boiling) water would cause serious injury. Water is a much better conductor of heat. Conductivity is basically just a measure of how quickly one object can transfer heat to another. An example on the cold end: dry ice is really really cold (-78 C) but can be handled briefly with nitrile exam gloves without causing any damage or even any significant discomfort."
],
"score": [
11,
9,
3
],
"text_urls": [
[],
[],
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|
[
"url"
] |
[
"url"
] |
|
lip2gc
|
Why did a day feel forever at age 10, but now at 25 it feels like 2 hours?
|
Biology
|
explainlikeimfive
|
{
"a_id": [
"gn4e7dq",
"gn4elb7",
"gn4erhz",
"gn4j5iz",
"gn5qskp"
],
"text": [
"In short : We have no clue exactly why it feels like that The predominant theory : That day took up a higher percentage of your life at 10 than at 25. One day at 10 is roughly 1/3650th of your life, whereas at 25 one day is roughly 1/9125th of your life. Another factor that plays into it is that at 10 you're still gaining a lot of knowledge every day, your brain has to record more stuff that may or may not be important later on, but at 25 your life is probably more mundane, you're falling into a much more consistent routine and your learning isn't as broad as before.",
"Memory and the feeling of time passing are both proven to be zipfian in nature (logarithmic decay i think?) URL_0 here’s a Vsauce video that talks about it",
"I think there are two parts that definitely contribute to this: 1. When you're young, you've lived fewer days of your life than now. One day to a five year old is a greater chunk of that person's life than a fifty year old, who's lived several times as many days as the five year old. In addition, when you're young, you've seen less of what life and the world has to offer, so you're bound to learn new things more often. This leads to part two... 2. Finding new experiences can make you slow down and think about life sometimes, and with each day usually comes the same routines, habits, and expected things. This can feel even faster if you manage to have the same job at the same employer at the same location for most of your life. It's like how your nose gets used to the smell of your house and starts to ignore it. Eventually you might live your average day on autopilot.",
"On average, adults are far busier than children. Time tends to feel like it passes faster the busier you are. Imagine a day in the life of a 10 year old vs that of a 25 year old. The 10 year old has school and some homework. The 25 year old has work, maybe social obligations, perhaps a lover, a family to take care of, Bill's to sort through, health appts to make, taxes to pay, politicians to vote for, sex to have, online forums to argue in, and on and on.",
"One of E.E.\"Doc\" Smith's characters may have put it best: _Subjective time is proportional to the amount of learning events experienced._ --Dave, I'm 56. You ain't seen nuttin' yet."
],
"score": [
12,
7,
5,
4,
3
],
"text_urls": [
[],
[
"https://youtu.be/fCn8zs912OE"
],
[],
[],
[]
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}
|
[
"url"
] |
[
"url"
] |
|
lipbs7
|
Why is black plastic unrecyclable and why is it still used?
|
Saw a utube today explaing that machines cant "see" black plastic used as food trays etc. If so why not change the colour?
|
Technology
|
explainlikeimfive
|
{
"a_id": [
"gn4hriv"
],
"text": [
"Because if a manufacturer thinks that a black tray sells their product better than that is what they will use. Recyclability of packaging will only be a consideration if it becomes a selling point in itself, which is slowly happening."
],
"score": [
8
],
"text_urls": [
[]
]
}
|
[
"url"
] |
[
"url"
] |
liphoc
|
Why are are astronomical objects typically in the form of a disc?
|
Saturn and its rings, our solar system, the Milky Way - Why are they (and the bodies orbiting them) in such a neatly flat shape and not more akin to how electrons are often depicted orbit an atom in all directions?
|
Physics
|
explainlikeimfive
|
{
"a_id": [
"gn4g0a2",
"gn4xnlq",
"gn4gq13"
],
"text": [
"There is something called the conservation of angular momentum, basically as things get dragged together by gravity they merge slightly off-centre so cause the combined object to spin, as new matter is added to the slightly spinning object they add to the spin depending which side of the object they merge with.",
"If you only have *one* object in orbit, it obviously orbits in a single circle -- actually an ellipse -- and that ellipse forms just one plane. If you have more than one object in orbit, they could start out in a single plane, but if their orbits cross, then eventually those two objects will smash into each other and become just one object, bringing you back to one plane. (Unless they bounce. We'll get to that in a moment.) If the orbits don't intersect, they will never hit each other. The most likely reason they won't intersect is because they are *already* in the same plane, orbiting parallel to each other, or close to it. So a bunch of objects orbiting in the same plane, just at at different distances, are pretty stable -- because none of the objects are crossing and hitting each other. So what about when two objects hit each other and then bounce? Well, what directions do they go after they bounce? It turns out that *on average*, they will bounce most in the direction they would go if they just smashed and stuck to each other. So if you start out with a sphere cloud of objects orbiting around the center randomly, after they hit each other over and over again millions of times, they will eventually *all* go in their *average* orbital direction, at least until you get to the point where they stop hitting each other. So by following the steps above, the cloud eventually becomes the disc shape that was the original \"average\". Sometimes you can get [objects from outside the system and don't stay in orbit]( URL_0 ) (in other words, they're not part of that average). Such an object can can knock one of the things a little bit out of the plane, because it changes the average. If the system is so mature (like the planets in our solar system are now) that that object no longer crashes into the other objects, it can stay out of kilter. Finally, let me say that those pictures of electrons \"in orbit\" no longer represent our best estimates of how electrons behave. We don't think that electrons anymore like little stones that travel continuously around the nucleus like planets orbit the Sun. Instead we now model electrons as winking in and out of existence in different locations (like Whack-a-Moles) in probabilistic \"clouds\" that can have various different shapes depending on how many other electrons are nearby. We still use the term \"orbit\" to describe the locations of those clouds, but we should probably stop doing that, because they don't involve movement that is in any way like the orbits that are produced by gravity. The behavior of electrons in those clouds is much more difficult to get your mind around, but when you finally understand it, it's super, super cool. Electrons travel kindof like Dr. Who in his tardis.",
"If objects are orbiting in all different directions sooner or later they collide tends to cancel out their momentum at an angle to the average direction of motion, so what's left is everything going the same way, ie a disc. Think of a multi-lane highway that everybody is going at the same speed but weaving in and out in regular ways. The collisions will be side to side and tend to straighten everybody's path out until all are moving straight down the road and collisions become less and less frequent."
],
"score": [
6,
5,
3
],
"text_urls": [
[],
[
"https://solarsystem.nasa.gov/news/473/what-we-knowand-dont-knowabout-oumuamua/"
],
[]
]
}
|
[
"url"
] |
[
"url"
] |
liq2bm
|
How do products get their final price?
|
Really broad question, and probably really simple, but when a product (of any kind) finally hits the shelves, what makes it the price that it is? How is it determined?
|
Economics
|
explainlikeimfive
|
{
"a_id": [
"gn55a54"
],
"text": [
"There are a lot of comments in here about the cost of the inputs to the product. This is wrong. Outside very specialized and explicit contracts, called \"cost plus\" and almost exclusively used in government/military contracts, the price has nothing to do with the cost. Products get their final price by the seller guessing what they can charge that will maximize profit (like /u/ViolettPapillon describes). This is entirely based on the buyers' willingness to pay, NOT what the product cost to produce. The only role cost plays is that if your suspected price is lower than your cost, you don't enter the market at all (because you think you'll lose money). As long as you reasonably believe you can charge more than it costs, you will price it as high as you think the buyer will pay. This is called \"value pricing\" and is FAR more common than cost-plus."
],
"score": [
5
],
"text_urls": [
[]
]
}
|
[
"url"
] |
[
"url"
] |
liqapo
|
How do certain medications cause weight gain? Don’t you need to be in a caloric surplus to gain weight?
|
Other
|
explainlikeimfive
|
{
"a_id": [
"gn4mhxy",
"gn4ow2n",
"gn4lo5j"
],
"text": [
"The \"calories in, carolies out\" paradigm of fat gain/loss is essentially true, but oversimplified and not especially useful without perfect knowledge and control of those those things. Medicines can make you tired and therefore move around less. They can reduce the calories you burn in the background. They can make you more hungry so you eat more - or if you resist the hunger, you body will likely slow down (a big problem for dieters, regardless of medication). Medicines can also increase or decrease the amount of water stored in your body, which changes your weight without relation to calories.",
"It doesn’t magically make weight appear out of nowhere. It makes you eat more, which makes you gain more weight.",
"Certain medications can mess with your feelings of hunger, or with how your body processes calories. So while yes, technically the medication isn't causing you to gain more weight directly, the effects it has on the body can lead people to eat more than they normally would."
],
"score": [
9,
4,
4
],
"text_urls": [
[],
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|
[
"url"
] |
[
"url"
] |
|
liqkj1
|
trademarked slogans
|
Other
|
explainlikeimfive
|
{
"a_id": [
"gn4nxq7"
],
"text": [
"This falls into the realm of legal advice for which you should seek a lawyer. The area surrounding things like trademarks is defined with broad legal language, the finer details of this language are tested in court. So whatever use you have in mind may or may not be legal. The question is, do you want to have to go to court to prove it? If it is for no commercial purpose, or you are using it for educational, informational, or comparative purposes, and you can't be confused with an actual Nike product or imply that you are being endorsed by Nike, you are more likely to be in the clear. When in doubt, don't use it. If you must use it, get their permission. If you don't get their permission, ask a lawyer of the appropriate discipline. Otherwise, good luck."
],
"score": [
6
],
"text_urls": [
[]
]
}
|
[
"url"
] |
[
"url"
] |
|
liqtsd
|
What makes cells different?
|
Ok, so high school bio got me as far as the concept of animal cells and plants cells. Great. Putting that behind us, animal cells can then be broken down into smaller categories right? From what I can tell, they are at least broken down by species and function, but are there further categorical reductions to be made? Just as an example; red blood cells vs white blood cells (both human), how and why are they structurally different? Do their organelles differ in size, shape, number or composition? What about two red blood cells from the same person, are they structurally identical? Could all human red blood cell mitochondria be considered interchangeable? Identical? I know the cell nuclei can't at least. I really want to stress structure here, not function. I know I just typed a lot of question marks, but I am not looking to have them all answered, just trying to convey the gist of what I am after. I think I am trying to understand the gap between the intracellular level and the atomic level. PS. slightly unrelated; when ATP is hydrolyzed into ADP and phosphate; is the energy released by that reaction the same heat energy that our bodies radiate? Is the phosphate the same phosphate excreted in our urine? Seems like it to me but I cant find explicit confirmation.
|
Biology
|
explainlikeimfive
|
{
"a_id": [
"gn4szk8"
],
"text": [
"Some good questions. A cell's structure is going to be tied to what it does. Since there are a lot of cells with different functions in your body, there are a lot of differently structured cells of all different size. For example, white blood cells are tasked with keeping your body safe from invaders. They have special components to them that a brain cell would not have, and brain cells have special components that white blood cells would not have. So cells can have different organelles, be different sizes, have different structural components, and have different numbers of organelles/components inside of them. Some cells have multiple nuclei (certain muscle cells), some have one, and some have none (red blood cells). Also, you mentioned red blood cell mitochondria- RBCs don't have mitochondria because they are tasked with carrying oxygen through the body, and mitochondria eat up oxygen to make energy. To your other question: ATP hydrolysis does generate energy (or transfer energy, if we're being precise in language). Simplistically, energy can be defined as either heat or work. Heat is what you think it is and work is when something does something. That thing could be pushing a box, forcing a sodium ion against it's concentration gradient, or anything really. The energy used in ATP hydrolysis is coupled with a reaction to provide some extra energy. Note: nothing is 100% efficient, so when performing work, some energy will be lost as heat. Please let me know if I've answered everything or if there's anything you'd want me to clarify on"
],
"score": [
5
],
"text_urls": [
[]
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}
|
[
"url"
] |
[
"url"
] |
liqzg8
|
Why can we bend our index finger's first joint freely but we can't bend our other fingers first joint(thumb excluded) without the others slightly retracting?
|
Biology
|
explainlikeimfive
|
{
"a_id": [
"gn4qs9g"
],
"text": [
"Your fingers don't move themselves. They're like puppets controlled by muscles in your arm. How they can move depends on where the strings (tendons) are attached. If you imagine a puppet hand (minus thumb) controlled by strings, with a glove (the skin) covering the hand and the strings, you'll get a better sense of the limitations."
],
"score": [
6
],
"text_urls": [
[]
]
}
|
[
"url"
] |
[
"url"
] |
|
liqzlz
|
Why do bananas “infect” other foods with their banana flavor?
|
You know how when you have a banana in a place where you keep other foods, sometimes your other food has a banana aftertaste, even if it was wrapped in plastic. How does that work? What chemicals are at play? How are they getting through other foods?
|
Chemistry
|
explainlikeimfive
|
{
"a_id": [
"gn4xdsq"
],
"text": [
"They naturally release ethylene gas that makes them ripen , the gas gets into everything near it ."
],
"score": [
9
],
"text_urls": [
[]
]
}
|
[
"url"
] |
[
"url"
] |
lir4dr
|
Why water that looks dirty on a bucket looks clear when u take some with your hand/palm?
|
Other
|
explainlikeimfive
|
{
"a_id": [
"gn4rmhw"
],
"text": [
"Less water means less dirt to reflect light. Also, the color of your palm overwhelms the relatively small amount of dirt; if you put it on a white sheet of paper instead, you'll probably see some dirt/color."
],
"score": [
3
],
"text_urls": [
[]
]
}
|
[
"url"
] |
[
"url"
] |
|
liriye
|
Why do we recognize CGI when we rewatch a movie years after seeing it the first time?
|
I went back and watched Avengers: Age of Ultron for the first time since it was originally released and for the first few scenes all I could focus on was how noticeable the cgi had become. I have vivid memories of being blown away by how realistic everything looked when I saw it years ago. As special effects technology improves, does that mean the way we recognize those effects also improve?
|
Technology
|
explainlikeimfive
|
{
"a_id": [
"gn4s1ka"
],
"text": [
"It's because CGI gets better and better slowly so we don't notice the change as much over time. Then when you look back at old stuff you have recent far superior CGI to compare to the less advanced stuff."
],
"score": [
11
],
"text_urls": [
[]
]
}
|
[
"url"
] |
[
"url"
] |
liroxt
|
Why does some face wash bring out more acne even if it considered harsher for you skin?
|
I've noticed that with some face wash I get more acne after use and I was just wondering if it just pulls all of the dirt up that wasn't noticable before or if there was some other cause. Sorry if the tag doesn't fit btw. I wasn't sure which one fit this better.
|
Biology
|
explainlikeimfive
|
{
"a_id": [
"gn4turt",
"gn8f76s",
"gn4tz0m"
],
"text": [
"Some harsher face washes have chemicals that severly dry out your skin. This temporarily may help your acne. But your body then notices how dry your skin is and will produces extra oils to moisten your skin. This increased level of oil then creates more acne and the viscious cycle begins again. I hope this makes sense.",
"Acne skin is really sensitive. Chemicals can make inflamation and swelling worse. You can also get an allergic reaction that can cause symptoms that seem to make the acne worse but are not actually acne.",
"From what i understand and from personal experience, your skin requires a degree of \"dirt\", that being healthy bacteria and oils that your skin produces naturally. We clean our faces to manage that oil and dirt. But unfortunately, when you do wash your face, it strips your skin of those oils and interfering with that' biome' can cause irritation and acne. I personally don't use face wash, I just use water and my hands because every wash I've tried, even gentle ones, are too aggressive for me. Au natural is the way my skin prefers."
],
"score": [
6,
3,
3
],
"text_urls": [
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}
|
[
"url"
] |
[
"url"
] |
lis0dc
|
- Why do cream infused liquors like baileys and kahlúa not require refrigeration and have such a long shelf life?
|
Chemistry
|
explainlikeimfive
|
{
"a_id": [
"gn4v70f",
"gn55u3y"
],
"text": [
"Alcohol is a natural preservative. The more alcohol is in something, the harder it is for anything else to grow in it. (In fact, this is why stronger drinks have to be distilled - there's only so much concentration of alcohol that fermenting yeast can live in, before it kills itself)",
"In general, anything above 40 proof is pretty shelf stable. Alcohol, salts, and tannins (like in wine) kill bacteria. In addition, if it's sterile going in and stays well sealed, it won't spoil at least until you open it. Sunlight can damage molecules (this is why most tasty things are in brown or green bottles), so you've got to keep them away from that. But why does bailey's not last forever? Eventually, you'll get some reactions, some separation / breakdown of the milk, a little bit of bacterial contamination, and things will just fall apart."
],
"score": [
23,
3
],
"text_urls": [
[],
[]
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|
[
"url"
] |
[
"url"
] |
|
lis8qb
|
How is it that some birds can exist in such wide temperature ranges with no apparent discomfort?
|
I live in an area where it regularly gets to be above 100 °F and today the temperature was as low as 31 °F. I saw, what I think is, a Great Blue Heron standing in a river. I assume it was waiting to catch a fish. How can they deal with such wild temperature extremes? I would assume that the water felt even colder than the air.
|
Biology
|
explainlikeimfive
|
{
"a_id": [
"gn505kr"
],
"text": [
"Feathers are extremely good at dealing with temperature regulation, a lot more so than fur which only insulates but doesn't cool an animal down. Feathers include multiple layers of insulation to keep the bird warm, but the feathers themselves can also flush blood through the shafts in the middle of them to cool a bird down. This is part of why many birds can live in a larger variety of areas than similar mammals can. As for standing in cold water, scales do give the legs some insulation but it wouldn't be very much, they just put up with being cold at that point."
],
"score": [
10
],
"text_urls": [
[]
]
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|
[
"url"
] |
[
"url"
] |
lisewh
|
Since epidurals are so commonly used to subside pain during active labor and child birth, why are they not used during other major medical procedures?
|
Other
|
explainlikeimfive
|
{
"a_id": [
"gn515vr",
"gn51hy7",
"gn4xu23",
"gn4zl3k",
"gn56yb7",
"gn521au",
"gn59uar",
"gn5xq9n",
"gn5zadb"
],
"text": [
"They do! They are known neuraxial blocks, which include spinal, epidural, and other commonly practiced regional anesthesia techniques. (I work for an anesthesiology group.) As a matter of fact, today I coded the billing for a spinal block on a patient who shoved a \"foreign body\" up his urethra and had to have it surgically removed.",
"This has a few parts so I'll break it down. Epidurals are used in child birth because they offer anesthesia from pain but while allowing the patient to still be conscious and push out a baby. During surgery it's generally preferable for the patient to be unconscious as well as not feeling pain, so an epidural is not recommended, general anesthesia is. For certain procedures like limb surgery or hand surgery a similar concept can be used called a nerve block, where only the nerve in that one limb is anesthetized, however the rest of the body is not. This is preferable when you want someone to be able to go home after a procedure like in ambulatory surgery or hand laceration repairs. It's really all about what you need from the patient, while making them as comfortable as possible, the first law of medical ethics is to do no harm for a reason.",
"My surgeon also used an Epidural on me for my lung cancer surgery. She said it was the most effective long term pain mitigation for that type of surgery.",
"Similar methods are used for other minor surgeries, like my hand surgery when they used a nerve block in my armpit. I’ve also had epidurals for pain relief, since I’ve had many surgeries and permanent damage.",
"Hello. Work in the anesthesia department. We use spinals for hip or knee surgery. Keeps the patient numb during the case and usually same day discharge vs general anesthesia. ( Longer recovery time in pacu and more drugs and anesthesia gas used.) Epidurals are primarily used for labor analgesia. Regional blocks are used for limbs. Examples would be shoulder or knee surgeries.Helps with post operative pain anywhere from 12-24hrs. Sometimes we use regional blocks for broken ribs but much higher risk due to proximity of the lungs being so close to the ribs. Some surgeons prefer both a spinal and also a regional block. All patient and surgeon specific.",
"They do. It depends on the anesthesiologist. For surgeries below a certain spine level, they'll give an epidural.",
"They gave me an epidural when I donated bone marrow. They take the marrow out of the pelvis, so big needles through the upper butt check multiple times. I don't remember much since they also gave me a Valium drip to \"relax\" me, which pretty much put me to sleep.",
"They are! For other major medical procedures epidurals and similar nerve blocks are usually combined with sedatives or other drugs to help keep the patient comfortable. Childbirth is generally just an epidural because the mother is an active participant pushing the baby out, most sedatives are dangerous for the baby, and the mother wants to be able to see and hold the baby right away, not forget the first hour of the baby's life in a medicated haze.",
"They can be. I had my appendectomy with an epidural. So I was awake though groggy.. felt weird with them digging around inside. And I've had foot surgery with a spinal block. That one was weird too. Was pounding on my legs and couldn't feel a thing."
],
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49,
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|
[
"url"
] |
[
"url"
] |
|
liskju
|
what does ‘enriched’ mean in the context of, for example, ‘enriched uranium’?
|
Physics
|
explainlikeimfive
|
{
"a_id": [
"gn4z9cf",
"gn50sg1",
"gn4yo06",
"gn52cqq"
],
"text": [
"It's been processed to increase the level of things that aren't normally in it. Natural sources of uranium has very little U-235, the most useful type of uranium. The enrichment process increases the percentage of U-235 in the sample to much higher than it would be in nature, making it more useful. Enriched foods have added vitamins and minerals. Enriched soils have had various things added to it which make it better for growing. An enriched person has more money.",
"Uranium has 2 main isotopes U-235 and U-238 but only the U-235 is useful in nuclear reactions. The process of separating the two isotopes is known as enriching. The part with a higher percentage of U-235 is the \"enriched uranium\" the leftovers are \"depleted uranium\"",
"This is when the percentage of U^235 has been increased through separation of the isotopes. There are a number of ways this can be done and it’s often very costly and time consuming. URL_0",
"Natural Uranium is mostly U-238 isotopes (99%) that isn't useful for Nuclear Reactors or Weapons. The Enrichment process helps separate the U-235 isotopes from U-238 to create higher concentration of U-235. Low Enriched Uranium (LEU) has concentrations below 20%. Nuclear Reactors use LEU generally. Highly Enriched Uranium has concentrations l 20% and above. Weapons use HEU, with typical weapons using 85-90% in their primary. [Wiki: Enriched Uranium]( URL_0 ) The Isotope Separation can be done using a [Gaseous diffusion]( URL_2 ) or [Gas Centrifuge]( URL_1 ) method. The latter becoming more economical and beneficial with improvements over time."
],
"score": [
14,
13,
4,
3
],
"text_urls": [
[],
[],
[
"https://en.wikipedia.org/wiki/Enriched_uranium"
],
[
"https://en.wikipedia.org/wiki/Enriched_uranium",
"https://en.wikipedia.org/wiki/Gas_centrifuge",
"https://en.wikipedia.org/wiki/Gaseous_diffusion"
]
]
}
|
[
"url"
] |
[
"url"
] |
|
lit5ct
|
How is it that birds can swim in freezing cold water and expose their feet to sub zero temperatures without suffering from frostbite?
|
It's something that's always baffled me, birds are everywhere in the winter with their exposed feet perched on branches, in water, or on top of ice, and they rarely seem to be affected by the cold in the same way that human skin is. How do birds not get frostbite?
|
Biology
|
explainlikeimfive
|
{
"a_id": [
"gn5329o",
"gn6855w"
],
"text": [
"Basically birds thermoregulate differently than mammals like humans do. Mammals use hair or fur to keep warm because they can't change their base metabolic rate easily. Birds usually just change their base metabolic rate to create more heat. Also their feathers are a better insulator than most hair, and they have a different blood circulation system to prevent extremely cold blood from the extremities from going straight back to the heart.",
"I have not seen this said yet. But birds and other ducks have a counter-current heat exchange system between their arteries and veins in their feet. Basically, the arteries and veins in the legs are close toward where heat exchange from the artery to the vein can take place. Warm artery blood goes to cold feet and makes it way back to heart. On the way back to the heart heat exchange from the artery warms up the vein blood. That is how they can swim in cold water."
],
"score": [
32,
5
],
"text_urls": [
[],
[]
]
}
|
[
"url"
] |
[
"url"
] |
lit6gz
|
I know many rice cookers use fuzzy logic (or fuzzy math?) So it cooks the rice the right amount of time. How does this work?
|
Technology
|
explainlikeimfive
|
{
"a_id": [
"gn5306d",
"gn5eych",
"gn5d6zj"
],
"text": [
"The basic ones are a bit simpler than “fuzzy” logic. Water can only stay liquid up to 100 degrees C. While there is liquid water in the cooker it’ll have a max temperature of 100C. Any excess heat put in gets used to turn the water to steam. When all the water is absorbed or evaporated the temperature can climb above 100C The cooker has a temperature sensitive strip on it that triggers just over 100C. This could be fancy circuits or it could be a bi-metallic strip with the right thermal properties. When all the liquid water is gone and the rice temperature goes above 100C the sensor trips and turns the cooker off.",
"Fuzzy logic in mathematics essentially allows for degrees of truth. Instead of binary choices like \"is this hot, or is it cold?\", in fuzzy logic something can be sort of or almost hot. So for advanced, computer-controlled rice cookers, using fuzzy logic allows them to move beyond the binary choice of the basic rice cooker (is it done, yes or no) and make decisions on how to cook the rice based on what's happening during the cooking process and how it is programmed to respond.",
"You don’t need fuzzy logic to cook rice properly. It’s just one of many control systems which are available on the market. The basic idea is to use the same logic as a non-fuzzy system would use (is there enough water? Did I heat it to the temperature when I should turn off the heater? Did all of it evaporate? Is it still warm enough to serve?) and introduce a bit of shades of gray in the chip’s reasoning. So, for instance, where a non-fuzzy system might continue to heat the rice because the temperature is not exactly right, drying it in the process, a fuzzy system will correctly handle a situation where the rice is _almost_ at the temperature but _barely_ started to dry up."
],
"score": [
75,
10,
3
],
"text_urls": [
[],
[],
[]
]
}
|
[
"url"
] |
[
"url"
] |
|
lititq
|
How is it possible that we are producing more stuff while our natural resources are depleting? (Manufacturing)
|
Other
|
explainlikeimfive
|
{
"a_id": [
"gn5800z",
"gn54dgk"
],
"text": [
"Your question has been partly answered by others, but one aspect hasn't been answered, which is to do with the value of the stuff that is increasing due to its increased uefulness. If we lived in a society where Earth's resources were just being taken and consumed directly, more production would mean more depletion. For example, if we were just picking fruit from wild trees and started picking more of it, we would run out of fruit pretty soon and some of us would have to starve until more fruit could grow than the rate at which we are picking it. But most of the value in our society doesn't come from things being extracted from nature, but from being created in the *way* we put extracted things together. We put together different things we find in nature, and create things that are way, way, way more useful and valuable. Think about, say, the raw materials that come from Earth that go into the making of an iPhone. You've got some metals, some plastics (oil derived products), some minerals, lithium for the battery, etc. Now, if you put all those raw materials in a little pile on the left, and put an iPhone on the right, you'd see the enormous difference in value between the pile of materials and the iPhone, due to the iPhone's usefulness. There's so much you can do with an iPhone that you just can't do with a pile of metal, plastics and minerals! That difference keeps growing over time, because we learn how to make ever more valuable things with ever less materials. We do more and more with less and less. Asymptotically, we will one day do (nearly) everything, with (nearly) nothing. This exponential accumulation of knowledge and ways to create more usefulness and value from existing resources is called \"ephemeralization\". Ephemeralization is the reason why it took Magellan a few years to travel around the world in the 16th century, while it took a steamship a few months in the 19th century, a plane a few days in the 20th century, and a space capsule a few hours today. We do more, with less. Not only that, but the rate of do-more-with-less-ness is increasing over time. This is how the value of what we manufacture can go up by orders of magnitude, while our available resources (sometimes) go down.",
"Resources are going down (faster) \\*because\\* manufacturing is going up. Resources going down is the not the same as resources running out. If we use up a resource, there's less of it available, because math. Some resources we can restore, or let nature restore. We call those renewable resources: wood, beeswax, food, anything we can grow (since it grows using the remains of old resources). Some resources we can reuse, those are the recyclables: aluminum (most metals), glass, etc. Some, once we use them, are effectively gone forever: oil, coal, uranium. Despite the absolute amount of many resources going down, we keep getting better at extracting them and more efficient at using them. The price of almost all goods is dropping in real terms as a result."
],
"score": [
6,
4
],
"text_urls": [
[],
[]
]
}
|
[
"url"
] |
[
"url"
] |
|
liu5bz
|
Why is 70 degree F water so much colder than 70 degree F air?
|
I can hang out buck naked in 70 degree F outside all day but not touching 70 degree F water.
|
Earth Science
|
explainlikeimfive
|
{
"a_id": [
"gn58big",
"gn5cr4r"
],
"text": [
"It's because of the efficiency of heat transfer--when thermal energy moves from something warm to something cooler. In this case, from your 98.7 degree (F) body to the 70 degree air or water. Water is a better conductor than air, so when you get into the water heat escapes/is transferred out of your body at a much faster rate, leaving you feeling colder, faster than you would if you were just standing in 70 degree air.",
"It's the rate of heat transfer. Liquids are much denser than gases. Picture liquids as a plastic ball pit, and gases as a mostly empty room with a few pingpong balls being tossed around inside. **70F air**: You are standing in a room where 2 or 3 people are tossing 70F pingpong balls at you. Your own temp doesn't change much because there aren't many impacts. **70F water**: You are submerged in a ball pit of 70F balls. Hundreds are contacting your skin all the time. You cool off much more quickly. Also the way you *feel* the temp of things is actually related to the *rate* of heat transfer in/out of you, not the thing's actual temp! Imagine a wooden toilet seat vs a cold plastic one. Both are the same temp but the wood one transfers your heat away slower, so it feels warmer. Go outside in the winter and compare touching a tree and grabbing a metal railing. Both are the same temp but the metal feels WAY colder, same reason."
],
"score": [
27,
7
],
"text_urls": [
[],
[]
]
}
|
[
"url"
] |
[
"url"
] |
liuao0
|
Why does the OECD exist?
|
I know only three things about the OECD: 1) It’s a policy-making body 2) Member countries aren’t required to implement OECD policies 3) The member countries have high GDPs But, I don’t know: 1) Why the OECD exists in the first place. Why would a country spend money doing research to come up with policies that the country may not even want to implement? Why wouldn’t they just fund their own (domestic) policy research to come up with policies that they actually do want to implement? 2) How often do the OECD member countries (and specifically, the U.S.) implement OECD policies as their own law? Can anyone help me understand this? Thank you!
|
Economics
|
explainlikeimfive
|
{
"a_id": [
"gn5djtt"
],
"text": [
"If the OECD had binding policies, no one would want to join, or they would at least have serious reservations about joining. Making them voluntary recommendations makes membership much more palatable. As for why join, two heads think better than one. While each country is unique, there are generally broad similarities that each country shares with some others. Aggregating and analyzing this data in a group can help find different relationships that might not be apparent. Also, even if member countries are different now, one may want to develop more similarly to another. Being part of the same “think tank” and being able to see some of their role model’s policy/data can be helpful in this regard."
],
"score": [
6
],
"text_urls": [
[]
]
}
|
[
"url"
] |
[
"url"
] |
liuejf
|
What causes some animals like rabbits and deer to defecate in pellets, while other animals have the "log" type?
|
And am I correct in thinking that cows, horses, elephants,etc. also have the pellet shape, albeit very large, that simply turn to "patties" when they hit the ground?
|
Biology
|
explainlikeimfive
|
{
"a_id": [
"gn5a6b8"
],
"text": [
"It's mainly because of natural predators. All animals need to poop, but the time spent doing so opens them up to attack in the middle of the act. A rabbit will poop small pellets. Doing so allows them to run away quickly and leave less of a trail than dropping a log and having it follow them back to where their home is. The Capybara actually makes square shaped poops and as a result, they don't roll down hill, which could lead a predator to their hutch. In short prey animals are able to shit quickly so that they can be on the move faster. Predators take longer to shit because they don't have any urgency."
],
"score": [
8
],
"text_urls": [
[]
]
}
|
[
"url"
] |
[
"url"
] |
liuesj
|
Why does the human body use fever to fight some types of infections and not others?
|
It seems that an earache is far more likely to provoke a fever response than, say, an infected hangnail. Is fever considered as a last resort for the body because of the metabolic costs, or does the body “know” that certain types of pathogens require specific kinds of immune responses (such as fever)?
|
Biology
|
explainlikeimfive
|
{
"a_id": [
"gn5ez70",
"gn6o9mk"
],
"text": [
"The latter. There is so, so much to get into here, but here's the short and sweet version. Many cells of the innate immune system are equipped with receptors that can recognize elements common to certain classes of pathogens. For instance, LPS (lipopolysaccharide) is a membrane component on many bacteria, and if picked up by the relevant receptor, that will kick off a signaling cascade in the immune cell that ultimately enacts an organized antibacterial response.",
"Like I'm Five: Your immune system is made up of lots of different guards that have wanted posters for certain types of criminals. Those wanted posters have information on them about what the criminal looks like, and how they like to commit their crimes. When the guards see a strange person, they check the wanted poster and see if the person they see matches the poster, and is, infact, a criminal. If it is a criminal, they light a beacon, that tells all the other guards that they have found a criminal, and calls for aid. The guards also tell the King, the immune system response (in reality this is vastly complicated, as are most other things in this process). The King, the immune system response, then decides the best way to fight the invading criminal and his gang of thug friends. Sometimes this just takes a few more guards, but sometimes it requires that the body heats up and makes it so hot for the criminals that they die. This is dangerous, sometimes, because the temperature that the criminals die at is not always lower than the guards, and other cells living in the body. & #x200B; For accuracy, check other posts."
],
"score": [
5,
5
],
"text_urls": [
[],
[]
]
}
|
[
"url"
] |
[
"url"
] |
liuzgg
|
teeth whitening kits
|
Can anyone explain to me how the teeth whitening kits that shine a bright bluish/purple light on you teeth work? How do they make your teeth whiter? For example, “Smile” was a popular one there for a while, and I believe Crest has one now as well. I assume that they must work... otherwise someone would have surely compared their teeth from a month before treatment to after and figured out there wasn’t a change. So how does that all work??! If someone can explain the science behind all that, it would be awesome! I attempted to search for some sort of answer on this forum for something similar, haven’t found anything. If there is one, please let me know. I’ll be sure to take this one down! Thanks!
|
Technology
|
explainlikeimfive
|
{
"a_id": [
"gn5dguw"
],
"text": [
"It's basically bleach, usually peroxide based. Oxygen transfers from the peroxide and attaches to stuff that stains teeth breaking it up and fading the color. The kits that come with lights use UV light to make the process happen faster, in a similar way that heating chemicals tends to make for a faster reaction. They still rely on a paste of some sort though. Definitely works well in a dentist's office, but I personally have no idea if the UV light in at home kits actually does anything. The dentist light is going to be a lot more intense, and a more energetic wavelength of uv is used that requires eye protection. The at home kits light is going to be safer and weaker so it really might just be a gimmick, and the kit may work just as well without the light. They do work though the effect is going to be a lot better if you only want to go from heavily stained to lightly stained. Getting to pure white is usually pretty difficult. Especially because if you use the kits too often they can weaken your teeth pretty badly."
],
"score": [
6
],
"text_urls": [
[]
]
}
|
[
"url"
] |
[
"url"
] |
livci4
|
Why is Air Humidity reported as a percentage?
|
Biology
|
explainlikeimfive
|
{
"a_id": [
"gn5e94o"
],
"text": [
"Actual moisture contents are of little significance to most people, but the current moisture content compared to the maximum for that temperature/pressure is at least somewhat useful."
],
"score": [
3
],
"text_urls": [
[]
]
}
|
[
"url"
] |
[
"url"
] |
|
livrxw
|
Why do kids seem to age faster?
|
How is it that a 4yo kid and an 8yo kid look and behave so differently while a 21yo person might as well look and behave the same as someone who is 5-6 years older?
|
Biology
|
explainlikeimfive
|
{
"a_id": [
"gn5ql81",
"gn5r1pk",
"gn7ip7l",
"gn6p4gd"
],
"text": [
"I think it's about how much new things you learn. Let's say a child that is born knows 1 thing. If he learns something new, that's twice as much as what he new before. After he has learnt 10 things, the next thing is only 1/11th as much.",
"Check out Piaget's stages of development for a deeper look at what cognitive change is going on, there is a big leap in cognition around 7 years old plus kids just get more capable at light speed when they are young because there's so much ground to cover",
"You are confusing aging with maturing. They aren't the same thing. Maturing is the process of a baby turning into a fully functional adult. This is what is happening with your 4 year old and 8 year old and is at time very rapid as you said. Once the child starts nearing the end of the maturations process, this slows down a bit and doesn't complete until the early 20s. At the point, maturing stops. The person has reached their adult stage. No more maturation. It's done. Aging, on the other hand, is a completely different process. It's basically a slow process of the body wearing out and breaking down over time. Over time the telomeres were out and the cells can replicate properly, mutations happen that requires cells to be shut down, cells that are never replaces start to lose their function, etc. The body is continually taking damage that's can't be fully repaired, and that is what we call aging. It's slow than maturation because your body prevents it the best it can, while maturation is something the body actively does. since both are part of our natural life cycle, we tend to lump them together, but they are two separate things.",
"They're still maturing. Post puberty at around the age of 18-21 you stop maturing, and basically would stay looking that way if it wasn't for the effects of ageing. And ageing is a much slower process than maturing."
],
"score": [
19,
9,
8,
6
],
"text_urls": [
[],
[],
[],
[]
]
}
|
[
"url"
] |
[
"url"
] |
livuuo
|
how GPS satellites handle a huge amount of requests?
|
Technology
|
explainlikeimfive
|
{
"a_id": [
"gn5l7bm",
"gn5lim8"
],
"text": [
"GPS satellites don't receive signals, they emit signals (and is always the same for everyone). Your GPS device must receive signals from at least 3 different satellite in order to calculate your position using a technique called trilateration. Each gps satellite has a known position in space (any given time) and his signal allows your device to know your particular distance to that satellite. Using the same information from other two satelites allows your device to calculate your position. So basically the magic is done in your device",
"GPS satellites constantly broadcast a signal to any device that's listening for it. Your phone doesn't contact the satellite. That signal says the current time according to the satellite. If a phone receives that signal, it can compare the time according to the signal to the time on the phone's clock. Based on how out of sync they are, it can calculate how long the signal took to reach you, and therefore how far away the satellite is. With three satellites, the phone can do some math and figure out its current location."
],
"score": [
15,
11
],
"text_urls": [
[],
[]
]
}
|
[
"url"
] |
[
"url"
] |
|
livuyz
|
Options trading. Will someone layout an example of how crazy amounts of money are lost trading options?
|
Economics
|
explainlikeimfive
|
{
"a_id": [
"gn5lkad"
],
"text": [
"On the purchasing side:. An investor [you] sees SPY $400 calls (right to purchase) currently available for $2 expiring this Friday [made up numbers]. You decide to purchase 10 contracts (100 shares per contract), for a total investment of $2000. SPY doesn't exceed $400, and the calls end up expiring worthless, and you lost all of that $2000 because you held onto the very end. . Selling an option: you think SPY won't go above $400 this week, so you sell 10 call contracts for $2 expiring Friday. Oh and for some reason you took the extreme risk of not owning any shares of SPY when you sold the calls. But suddenly SPY jumps to $420. The option is exercised, and you are forced to purchase 1000 shares at $420 and immediately sell them for $400, netting you a $20,000 loss minus the $2000 premium you received selling the contract. [Hence why brokerages require a high level of approval before they will let an investor sell call options \"naked\" (not secured by shares of the underlying equity)]"
],
"score": [
3
],
"text_urls": [
[]
]
}
|
[
"url"
] |
[
"url"
] |
|
liw4tk
|
How come mosquitoes like to bite me and not my girlfriend?
|
We'll go on a hike and I'll get eaten alive and she won't even get a bite.
|
Biology
|
explainlikeimfive
|
{
"a_id": [
"gn5olxa",
"gn6f878",
"gn5owij",
"gnbde49",
"gn66boz",
"gn9ib2k"
],
"text": [
"What’s your blood type? No seriously lol lots of [research]( URL_1 ) has shown that people with [O type blood]( URL_0 ) are much more [likely ]( URL_2 ) to get bitten than other types. It could also be that she uses repellent and you don’t, or if you do, she applies to more liberally, uses a stronger one, or re-sprays after the 4 hours.",
"I got bitten all the time before I had kids. Since then, barely ever. Same thing happened to my mum. Different pheromones?",
"Some mosquitos can only drink a certain type of blood like a positive, b negative, so and so fourth. Im pretty sure there would be more mosquitos that follow a commen blood type. Maybe your just one of them while your girl probably has a rare blood type.",
"Totally unscientific, but all people I’ve met who get bitten a lot (myself included) have A+ blood type.",
"There is definitely evidence that attractiveness to mosquitoes is genetic. Granted those same studies don't exactly show the mechanisims behind it, just that it can be inherited. Most assume that is has to do with body odor though there are definitely other opinions. I've seen blood type, and immune response to bites among the theories.",
"Eating bananas is known to increase your attractiveness to mosquitos. Also, CO2 and H2O vapor attract them. [this]( URL_0 ) is worth a read. Lactic acid is another thing. > Mosquitoes are big fans of lactic acid, an organic acid that can be produced in your skin, along with other areas of your body, Walker says. “Mosquitoes happen to have a specialized receptor as a way to sniff lactic acid,” he explains. Some people simply produce more lactic acid than others, luring in more mosquitoes, but you also tend to give off more lactic acid when you sweat. Bacteria on your skin can also play a role Being pregnant or overweight, drinking alcohol, and physically exerting yourself can all raise your metabolic rate, which causes you to produce more attractors. > An older study published in the Journal of Medical Entomology found that mosquitoes landed on people with type O blood 83% of the time, but were only attracted to those with type A blood 46.5% of the time, but more research is needed to understand why. “Mosquitoes partially rely on their vision to find their hosts, and dark-colored clothing can make it easier for them to find you,”"
],
"score": [
11,
4,
4,
3,
3,
3
],
"text_urls": [
[
"https://time.com/3311624/why-mosquitoes-bite/",
"https://www.healthline.com/health/mosquito-blood-type",
"https://www.treehugger.com/reason-mosquitoes-bite-some-people-more-others-4858811"
],
[],
[],
[],
[],
[
"https://www.msn.com/en-us/health/wellness/its-true-mosquitoes-are-attracted-to-certain-people-more-than-others/ar-BB15FN04"
]
]
}
|
[
"url"
] |
[
"url"
] |
liwi3p
|
why does the wii remote work when you put fire in front of it?
|
URL_0
|
Technology
|
explainlikeimfive
|
{
"a_id": [
"gn5va82"
],
"text": [
"The Wii bar that you put near your screen is just two infra red LEDs, the Wii remote has infrared receivers and is just looking for an infrared source, because anything hot is an infrared source all it needs to be is hot enough."
],
"score": [
24
],
"text_urls": [
[]
]
}
|
[
"url"
] |
[
"url"
] |
lix0zm
|
Are spiders webs and the cobwebs you'd see in old abandoned places different things? How are cobwebs formed?
|
Earth Science
|
explainlikeimfive
|
{
"a_id": [
"gn61kzd",
"gn6292x",
"gn61xiz"
],
"text": [
"\"Spider web\" is typically used to refer to a web that is apparently still in use (i.e. clean), whereas \"cobweb\" refers to abandoned (i.e. dusty) webs.",
"Cobwebs are just old spider webs that have been made in places where they won't get broken or blown away and have collected dust on the sticky strands that makes them more visible.",
"Cobwebs are abandoned spiderwebs. Spiders spend a lot of time maintaining their webs to keep them functional, it doesn’t take that long for a spider web to gather dust and loose it’s stickiness and function as a trap for the spider’s food."
],
"score": [
9,
3,
3
],
"text_urls": [
[],
[],
[]
]
}
|
[
"url"
] |
[
"url"
] |
|
lixae7
|
base 10 counting
|
Mathematics
|
explainlikeimfive
|
{
"a_id": [
"gn66518",
"gn672je"
],
"text": [
"Base 10 is just the normal 0-9 counting system. Base 2 would be binary (0 or 1), and hexadecimal is base 16 (0-9 then A-F). The base refers to the number of digits you have to notate the numbers, 0-9 is ten separate digits so it's base 10.",
"> Base ten counting is a new concept that I got introduced to and it doesn’t make sense to me. It doesn't make sense because it's a new name for something you already do. \"Base X\" just means that there are X numerals that define the way you write numbers. Base 10 means 0-9. Once you hit 9, you roll over to the next place, and start again. 00 01 02 03 04 05 06 07 08 09 10 ...and so on. This is analogous with any other base."
],
"score": [
3,
3
],
"text_urls": [
[],
[]
]
}
|
[
"url"
] |
[
"url"
] |
|
lixl1w
|
Why do we retain memories if all of our cells replace themselves after a small amount of years?
|
Biology
|
explainlikeimfive
|
{
"a_id": [
"gn6fnr9",
"gn8tjpd",
"gn6j9w9",
"gn7z0ma",
"gn83zmv",
"gn7s5kj",
"gn7x9p8",
"gn8alkm",
"gn8dvyv",
"gn87klm",
"gn87ykt",
"gnbpeap",
"gncvapx",
"gn897eg",
"gn8dbcz",
"gn8xdbr",
"gn86wsv"
],
"text": [
"The concept that all your cells regenerate within 7-10 years is based on some misconceptions. Different types of cells regenerate at different rates. Some only last a few weeks while others last your entire life. Most of your brain cells are in the later category. The 7 years is based on an estimated average of all your cells. And while we do not know much about how memories work there is some evidence suggesting that memories gets refreshed when you are asleep so that even if brain cells do not last your entire lifetime but gets damaged somehow the memories will get restored and refreshed from time to time.",
"To be honest, having spent the last 15 years as a PhD neuroscientist, no one actually knows how memories are stored. Specifically because the cells and connections in the “memory” areas keep changing, and new ones WILL grow there. There are some theories that memories are stored in the connections between the cells AND in the dna superstructure (modifications to the backbone of dna, not the code). There’s no explain like I’m 5 for this one, because no one knows.",
"This is very simplified but... If you’ve ever seen a swirling eddy in a river, you’ll observe that the water composing the formation is passing in, around, and out very quickly - yet the pattern in the river is sustained. Depending on the surrounding conditions, it can be very stable and long lasting. The water is your cells, the eddy is you.",
"Because not all cells get replaced in a few years. ...and even if it happens, memories are not stored inside cells, but by connection between cells, so as long as there is another cel to take up the slack, there is no problem.",
"Not all cells of our body are replaced, for example, neurons, aren't replaced ever, they do not divide so that's why if you lose too many you may develop some mental illness, but even if they divided the information retained would be passed onto the new cells therefore your memories would go along, skin cells, for example are replaced if they die.",
"if you replace every piece of a house (brick, tiles, shingles ecc) one by one you still get the same house",
"Well, to be frank, how many memories do you really retain if you don’t reinforce them? Try to think about how ridiculously huge amount of thoughts and inputs throughout your life that you will never remember - memories lost.",
"While there is neurogenesis (growth of new neurons) in some parts of the brain--like the hippocampus, which is involved in memory formation--this concept doesn't really apply to the brain on the whole. When neurons die, they generally don't come back.",
"Neurons (brain cells) last a lifetime! The ones you were born with are the ones that are in your noggin right now.",
"Because it’s not the cell that hold the memory it’s the pattern the neuron (cell that basically let you think) is in so as long as the new cell is in the same place as the last then it won’t affect your memory. A memory is basically a combination of neuron patterns like one for the way an experience smelt and one for the way it looked and one for the way you felt and so forth. This is why smelling or feeling something can trigger a memory that you couldn’t just recall at will. The patterns that form smell, touch, sight and so forth all link up and so you remember a situation in detail. Your brain puts all the puzzle pieces that it thinks relate together even through on their own they don’t make any sense. This is why when you remember something it’s very likely that there’s a detail you swear happened but it didn’t actually happen, same as when someone else who was there swears it didn’t happen even through you can remember it so clearly. Your brain isn’t perfect so it can add things that weren’t actually in the original memory into it because they were similar enough to be put there. I hope this was simple enough well also explaining your question and potential questions",
"imagine your body is a city, imagine your cells are buildings. some buildings like brain cells might be like government buildings, or docks like your mouth. roads like veins and arteries... like others have said, some cells/buildings get replaced more or less often than others. but on top of this, there are always similar cells/buildings near by. if for instance your house had burned down and needed to be rebuilt, you could stay at a family members house or a hotel, essentially somewhere that would serve the same function. currently in quarantine, many people work from home or school from home. in your body cells are so densely packed and built up in dedicated areas, that the safety net and redundancy for each individual cell is significant. consider how your skin operates multiple layers working together, providing redundancy and support, as well as different levels of utility. or even your finger nail, layers at the back growing and pushing layers to the front ready to take over from the previous.",
"Memories aren't in cells. They're passed around in synapses and electronic pulses like trains moving around on train tracks. The tracks need replacing every few years, and there are some old trains still around, but more new ones - really old trains are taken off the tracks.",
"i think of my brain like a computer, if i can’t remember something i literally say out load “little man go fetch” and imagine a mario type of fella running up the corridor of my brain - the trick is to let him do his stuff snd stop thinking about it- in no time at all what ever u were trying to think of pops into yr head !!!",
"You don't store memories like 1 cell 1 memory, concept or idea or some simplification like that. It is more like the connections within them that helps you to build a network and that network helps you to recall information. You also have certain redundancy and you store different memories in different places (easy access and long term stuff etc). But as other redditor said, you \\[normally\\] don't lose your brain cells.",
"Memories themselves degrade over the years. Every time you recall a memory, sometimes within the memory changes. It starts with very small fine details, and over the years all you're left with is the impression or how you felt and maybe some visions of what happened. But even then you aren't remembering what happened, you're remembering what your brain saw and perceived at that time. Certain things like smells, and sounds do have a profound effect on our ability to recall things as well.",
"The memories aren't stored in your cells, they're stored in the ARRANGEMENT of your cells. It's like, imagine a light switch that's turned to the \"on\" position, but like sitting on a counter. Imagine replacing every piece of it one by one, the cover, the backing wiring, the cover for the switch, etc, with a copy of the exact same part in the exact same position. After you were done, you'd have a totally different light switch, every part would be different... But it would still be switched on.",
"If it were true that every single cell you now have since making a certain memory is now different, I think it has to do with the fact that what makes you is the same thing that makes a school of fish, a swarm of bees, etc. you are a hive mind, and be it a matter of cells sharing 99.9999% of all information from time to time OR the fact that you’re not your cells, you are the electrical synapses that dances between them, you can rest assured that if your cells are constantly dying and regenerating you are still going to be YOU."
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|
[
"url"
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[
"url"
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|
liye99
|
Who exactly pays for the meal when its "on the house"?
|
Other
|
explainlikeimfive
|
{
"a_id": [
"gn6o2yd",
"gn6ojc8",
"gn7w76k"
],
"text": [
"The restaurant covers the cost. Typically restaurants have budgets for food waste, so it will come out of there and they’re allowed to do so. That meal that costs you like $12, may cost the restaurant $2-3",
"It means no price to you. The house is the “establishment” so the owner of the restaurant isn’t charging you. But it still cost him to buy three ingredients store them have someone prep them, make them to order clean the dishes etc so it’s not “free”. Also if you’re in a service restaurant it reminds you that even though you’re getting a deal it’s still a transaction so don’t forget to tip the server.",
"Most restaurant managers budget for a certain dollar value in 'comps' (free food) they can give away each week / month. Some of this food might go towards someone who's food was messed up, or a birthday sundae, or just towards employee meals."
],
"score": [
92,
38,
3
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|
[
"url"
] |
[
"url"
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|
liyoe3
|
Why did the dollar have to be put off the gold standard?
|
Economics
|
explainlikeimfive
|
{
"a_id": [
"gn6y2v8"
],
"text": [
"Money didn’t lose gold value. It was just a convention at the time. Dollar and most other currencies were on silver standard much longer than they ever were on gold; until a ton of new silver deposits were found and flooded the market. So if you can manipulate a currency by simply throwing in more of a commodity in the market, it’s clearly a poor idea. Gold, because it was significantly rarer than silver, was thought to be the solution to this, but that also meant that there can only be so much money as one had gold; I.e. the economy was only as big as the gold reserves. Since you can clearly create value by manufacturing say cars, or giving people haircuts, putting an artificial ceiling to the value an economy creates was not a great idea either. Or theoretically you could keep the gold standard and keep changing the exchange rate every time new economic value is created - today $1=1g of gold, tomorrow $1=0.9g of gold, two days later it’s 0.8 etc...not very meaningful, and honestly, impossible to do. So, instead of artificially creating a sum of value, you create what is known as fiat currency - backed by trust in the economic and political system: people trust that they can exchange X amount of currency for Y amount of goods & services; and the social system supports that belief."
],
"score": [
4
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|
[
"url"
] |
[
"url"
] |
|
lj0vvv
|
which is better for you, and why: Drinking smaller sips of water consistently throughout the day, or drinking "big gulps" like a half/whole bottle of water periodically through the day?
|
Biology
|
explainlikeimfive
|
{
"a_id": [
"gn7ulgk"
],
"text": [
"It generally doesn’t matter, so long as you get enough hydration and don’t drink too much water; it is possible to over-hydrate yourself, and doing so causes damage to your kidneys. Example; once upon a time, a contest was held and the reward was (I believe) a gaming system. The goal of the contest was to drink a gallon or more of water and refrain from urinating as long as possible. One woman died as a result, as her kidneys failed. Over-hydrating can also cause an electrolyte imbalance that leads to a deadly arrhythmia. *HOWEVER*... It is very rare and highly unlikely that you’d drink that much water without doing so intentionally, meaning if you’re just drinking because you feel thirsty, you’re going to be just fine."
],
"score": [
7
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|
[
"url"
] |
[
"url"
] |
|
lj10lb
|
How do people with health insurance end up with bills over 10k?
|
Other
|
explainlikeimfive
|
{
"a_id": [
"gn7s20n",
"gn7vsdt",
"gn7qvo6",
"gn82fpa"
],
"text": [
"There are 2 maximums that can apply: the in-network out of pocket maximum is $8,550 (single) and $17,100 for a family under the Affordable Care Act limits for 2021. The out of network out of pocket maximum is often double or more. There are 3 ways you can exceed this and have to pay: 1. Services your plan doesn’t cover do not count toward your out of pocket maximum. 2. You use out of network providers 3. The provider you use charges above the allowed charge. Source: I design and manage benefit plans for a living.",
"My family had a 12k max out of pocket in 2016. My wife was diagnosed with Stage 3c breast cancer. Our total out of pocket over 3 years was more than $60k, despite the yearly max of $12k. Without getting in to ridiculous details, we opted for better options that were not covered. Our goal was survival and doing everything and anything to make her comfortable. So wigs, better plastic surgeon (who typically don’t even accept insurance), advanced screenings, genetic testing, heck, the machine to automatically inject her with Neulasta 24 hours after chemo (so she didn’t have to travel to the clinic the day after chemo) was $14k per 6 ounce shot! The whopper was a surgeon who had left our insurance provider prior to surgery, got a bill for $298,000. Took a year of legal intervention to fix that one. The real issue here is, there is just so much that goes in to serious treatments, you can’t possibly track everything and make sure everything is covered, especially when your focus is on your family and your own mental health.",
"It is covered past a point, in the case you mention that point is 8k for singles and 17k for families (on that specific plan). The problem is when you end up at an out-of-network hospital. Not all health plans cover out-of-network hospitals to the same capacity as in-network ones, and some don't even cover it at all. If the procedure at the hospital you end up at isn't covered, you're liable for the bill. This happens because you don't exactly get to say which hospital you want to go to when you're unconscious in the back of an ambulance.",
"As you note - the out of packet can be tens of thousands, with the exact amount varying by plan A lot of folks do not have tens of thousands lying around so clock up tens of thousands in medical debt. Another factor is bullshit with “out of network” (OON) providers. When you go for surgery the surgical crew mostly aren’t hospital employees, they’re private contractors and you have very little control over how much any of them interact with you or information whether they’re in network (IN). Even if the hospital and surgeon is IN they might have an OON anesthesiologist, and you have no ability to pick this person, and for even higher levels of BS look up the crap surrounding OON surgical assistants. These are folks pulling in 40-60k who are billed to you at an OON $1000/hour or so - they work for a company owned by the surgeon who gets to keep the profits. It looks a lot like insurance fraud... Then there’s people who end up with higher bills than they should because between the hospital billing dept and the insurance company, both large companies with extensive staffs of insurance billing experts, regularly fuck up the coding and billing and send clients bills they shouldn’t be getting sent and then the lay-person patient has to go through months of effort to get the hospital and insurance company to apply the correct benefits and coding to the treatment. This is a regular topic on r/personalfinance But most of it is even with insurance you can end up legit owing five figures per treatment year, and a lot of folks don’t have that money lying around."
],
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15,
8,
4,
3
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|
[
"url"
] |
[
"url"
] |
|
lj1976
|
do moon phases really have influence on plant planting and growing, or is that is that a myth?
|
Biology
|
explainlikeimfive
|
{
"a_id": [
"gn880gi"
],
"text": [
"There have been studies and none could show a statistically significant effect. If one exists it's very weak. But since we don't even have a theory why it should have some effect it's most likely a myth."
],
"score": [
6
],
"text_urls": [
[]
]
}
|
[
"url"
] |
[
"url"
] |
|
lj1f4t
|
how is a micro hemorrhage different than a stroke?
|
Biology
|
explainlikeimfive
|
{
"a_id": [
"gn7zvwp"
],
"text": [
"Hemorrhage is simply a rupture of some blood vessel, resulting in blood escaping into the tissues. And as the name would suggest micro hemorrhage is a very small hemorrhage (usually a result of ruptured capillaries - the smallest blood vessels). There are two types of stroke - ischeamic (the more common one, caused by an obstruction of a blood vessel in the brain) and haemorrhagic (caused by a heamorrhage in the brain). The result of both of those types is a damage of the brain cells with a wide range of symptoms. So, I would say that a difference between micro haemorrhage in the brain and a heamorrhagic stroke is just the scale of the problem."
],
"score": [
5
],
"text_urls": [
[]
]
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|
[
"url"
] |
[
"url"
] |
|
lj1w2s
|
What does a GPU do when you play a game.
|
Technology
|
explainlikeimfive
|
{
"a_id": [
"gn82s2l",
"gn86jaf"
],
"text": [
"For your computer at home, games are harder to run fast than the other things you're probably asking it to do. There's a lot of math the computer does in the background trying to figure out where all the stuff in the game is and how it should look on your screen. If your computer can't do all that math test enough, the game will run too slowly to play and it might not even run at all. The GPU is an assistant that does all that extra math for your computer. It's really good at doing geometry - calculating angles and stuff, which is the kind of math that games need. So it does as much of the extra math involved in figuring out what goes on the screen so the rest of the computer can keep doing the rest without getting overloaded.",
"A GPU is a Graphics Processing Unit. It processes the graphics for the game. It's a chip that's specialized for doing lots of relatively basic stuff, which is good for graphics processing. It puts all the pixels on the screen. Meanwhile the Central Processing Unit processes everything else, like where the monsters are going and how many health points you have. The CPU tells the GPU \"display a monster at these coordinates: 123, 456\" and then the GPU actually translates that instruction into pixels. Some old game consoles used to have a Sound Processing Unit, but these days the CPU is fast enough to calculate the sound as well, so it doesn't need a separate processing unit. Not all games use the GPU. The CPU can process anything, even graphics. The GPU just processes graphics more quickly and lets the CPU do other stuff in the meantime."
],
"score": [
10,
5
],
"text_urls": [
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|
[
"url"
] |
[
"url"
] |
|
lj22v0
|
Why does the skin of an apple taste sweeter or "taste-y" than its flesh?
|
Shouldn't the flesh, which has more sugars, taste sweeter? Question by an 8 year old.
|
Other
|
explainlikeimfive
|
{
"a_id": [
"gn82xt9",
"gn82tu2"
],
"text": [
"Depends on preference. Tell the 8 year old that not every person likes the taste of the skin as much as other people, I guess?",
"The skin is where the fiber is. Skin needs lots of chewing? Or maybe it’s because they’re genetically modified for specific tastes? The pulp is mostly water."
],
"score": [
5,
5
],
"text_urls": [
[],
[]
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}
|
[
"url"
] |
[
"url"
] |
lj2gph
|
. Why do mirrors flip the image horizontally and not vertically?
|
Physics
|
explainlikeimfive
|
{
"a_id": [
"gn88xs5",
"gn8bu31",
"gn8ad2e",
"gn8b4o5"
],
"text": [
"Mirrors don’t flip an image. They just reflect what’s directly in front of them. Imagine painting your body with blue paint and then walking into a white canvas. What would the canvas look like? Your feet would paint the bottom, your head would paint the top etc.",
"Mirror flip images back to from not horizontaly Put a mirror north of you and look directly at it. Your right arm is on the east side and if you move it the reflection of you moves the eastern arm. The same is for your arm to the west. Jump up and down and the reflection moves the same way. There is a difference if you talk about left and right arm but that is because it is a relative definition and it no different to if you look at someone saying in front of you looking toward you But if you move away from the mirror to the south the reflected image move to the north. This is the flip back to front. Mirrored text looks like that because you look at it from the back. If you write text on a window and look at it from the backside look just like in a mirror. You can use a mirror to read that text correctly.",
"They don't. Your right eye is on the right, left arm is on the left. You try to turn things around in your brain to make it fit with how you're used to physics, but it's just a reflection.",
"Some mirrors do flip images vertically. Like the inside of a spoon. Also, you eyes take up light upside down but your brain corrects it, so in a way, mirrors DO flip images vertically!"
],
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6,
6,
5,
3
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|
[
"url"
] |
[
"url"
] |
|
lj2jhz
|
- Why is carbs management important for weight gain/loss? Shouldn't calories surplus/deficit be all that matters?
|
I know your body can convert carbs into adipose tissues easily, but at the end of the day, if you are in a 1000 kcal deficit and eating only protein, what is the difference with the same calories deficit and eating only carbs? EDIT : Sorry guys, I think I should have phrased it more carefully. I am not asking about how full I feel after eating one or the other or how easy a diet is to follow, I am asking mechanically, why is a specific type of macronutrient more relevant than a calories deficit when it comes to the way your body handles fat loss.
|
Biology
|
explainlikeimfive
|
{
"a_id": [
"gn89hdh",
"gn89xvf"
],
"text": [
"If you were a robot, yes. But successful diets are ones that are easy to stay on the plan. If you're hungry all the time, you may not stay on the diet. Proteins and fats will keep you feeling full longer. Carbs will leave you hungry sooner after eating the same amount of calories.",
"Mostly that it's harder eating the same amount of calories with just carbs. Carbs are either burned quickly or stored, and then you feel hungry again. Proteins take longer to digest and release some energy over a longer period. Carb isn't carb though, sugars are the quickest, starch takes a bit longer and is therefore less problematic."
],
"score": [
6,
3
],
"text_urls": [
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|
[
"url"
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[
"url"
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lj2uow
|
everything is made out of atoms, is there a possibility to cut an atom accidentally with a knife and thus leading to reaction of some sort?
|
I am not sure if its a rly dumb question, probably is but I was just wondering isn't it possible to accidentally, at some point in life cut an atom in half since they are everywhere? If the said scenario is possible what exactly would happen? Can it even happen? Imagine you are cutting tomatoes, if there is an air atom somewhere in the cutting board, isn't there a chance even tho its rly small that I will hit exactly the spot by accident and by doing so cut an atom?
|
Physics
|
explainlikeimfive
|
{
"a_id": [
"gn8e01a",
"gn8crnp"
],
"text": [
"No. A knife edge is also made of atoms (or really molecules which are even larger than atoms). Think of cutting something like a person moving through a dense crowd. The person can push others out of the way and slip in between, but they are just a person as well, and they aren’t going to be able to just split another person in two to get through. Edit to add a little more: It's also that the link between atoms is much easier to break than splitting the atom. So in my analogy, imagine the people in the crowd are loosely holding hands. It's easier to push them apart than to well, split the people in half.",
"No. The energy required to break an atom depends on the atom. Some are unstable and can break up on their own. But even those atoms can't be broken by the level of energy you can put into a knife. The atoms in a tomato are the most stable kinds, so that's out of the question."
],
"score": [
51,
4
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"text_urls": [
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|
[
"url"
] |
[
"url"
] |
lj2vrk
|
Why do shoes narrow at the toes?
|
This is not how feet are shaped. What's the deal?
|
Other
|
explainlikeimfive
|
{
"a_id": [
"gn8gmx3",
"gn9pv1q",
"gn8ndu5"
],
"text": [
"This design is often seen in shoes designed for women. The reason is to make women's feet look smaller like an optical illusion and smaller feet is often seen as a sign of beauty. [Look at this picture]( URL_1 ) and you tend to ignore the length of the foot itself and focus on the overall shape. The smaller tip implies that the foot itself is smaller than it normally is. [Now look at this picture]( URL_0 ) where the foot looks bigger because of the abrupt end near the toes.",
"Good question. Aesthetics. Not all shoes do. In some designs, the toe area is wider, mimicking your actual foot, like Crocs and clogs. They are popular bc they are comfortable.",
"The narrow shaped shoes does a great job at protecting your toes when bumping against hard surfaces, imagine bumping your toes against furniture with some feet shaped shoes, you bump your toes against all kind of objects in a daily basis more than you can imagine, thanks to the tip pointed shoes humankind lives a less painful life."
],
"score": [
23,
5,
3
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"text_urls": [
[
"https://images.dresshead.com/images/womensshoes/Camel%20Heels/805355004/large/3.jpg",
"https://cdn.shopify.com/s/files/1/0501/2485/products/nude_pointe_toe_flats_pointy_800x.jpg?v=1576455592"
],
[],
[]
]
}
|
[
"url"
] |
[
"url"
] |
lj3l09
|
Why does 2 identical sounds heard at the same time sounds louder ?
|
Physics
|
explainlikeimfive
|
{
"a_id": [
"gn8o3b5"
],
"text": [
"Sound is an oscillating pressure wave propagating through a medium, such as air. If you have two identical sounds hitting your ears at the same time, you have twice the energy being transferred to your eardrums."
],
"score": [
5
],
"text_urls": [
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|
[
"url"
] |
[
"url"
] |
|
lj3yhi
|
how does something rough like sandpaper, make something smooth?
|
Physics
|
explainlikeimfive
|
{
"a_id": [
"gn8s6jy",
"gn8upag"
],
"text": [
"The smoothness comes from the material being uniform in height. So if you have a rough block of wood, there's a whole bunch of bits of wood that are taller than adjacent bits of wood. When you sand it, you scrub away those taller bits until everything's on the same level.",
"Think of a surface as something that has a lot of peaks and valleys. Sandpaper generally wears away the peaks and doesn't hit the valley, so the surface gets more level. Typically, you'll go from a rough grit to a fine grit. Finer grit sandpapers wear away the peaks from the scratches of the rougher grits. You turn big scratches into little scratches. And you can keep doing that until you have a mirror finish."
],
"score": [
29,
4
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"text_urls": [
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|
[
"url"
] |
[
"url"
] |
|
lj3zyr
|
How is a jellyfish considered an animal without a brain?
|
Biology
|
explainlikeimfive
|
{
"a_id": [
"gn8rc23",
"gn8r9u9",
"gn8xmg3"
],
"text": [
"Having a brain is not what defines an animal. Animals are defined as animals because they share a common origin, they all have certain specific kinds of cell junctions, and they all go through similar embryonic development. Brains are just something a lot of animals have, not something they all have.",
"Jellyfish might not have a brain, but they do have a nervous system. Two, in fact. They are both spread out like nets or mesh.",
"Animals aren't defined by possession of a brain or sense of awareness or anything. \"Animals\" are grouped together by evolutionary relationship. Jellyfish (or rather, their parent group) split off from the rest of the animal kingdom many many years ago - long before those other animals developed qualities we commonly associate with animals today, but after animals as a whole split off from plants and fungi. If you look at the tree diagram on [this]( URL_0 ) page it might help visualise this. You read these right to left, with each point where two lines merge representing a common ancestor from which each meeting branch diverged. Jellyfish (Cnidaria) have a common ancestor with Placazoa, and that common ancestor shares a common ancestor with Bilateria. Bilateria is the first animal to develop bilateral symmetry (basically, being able to draw a line of symmetry down the middle of the organism) and is the organism that all animals with bilateral symmetry are descended from. It would then take until the Chordata (a subset of Deuterostomes) for the notochord (basically the central nervous system) to appear several hundred million years of evolution after Jellyfish diverged. Animals go back a lot longer and to a lot stranger things than it might at first appear. We're really getting into the depths of evolution at this point, and if you had told animals back then that one day their descendants would be lumps of flesh that grow rocks inside themselves for support they'd look at you as if you were mad."
],
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}
|
[
"url"
] |
[
"url"
] |
|
lj44q8
|
How and why do waves 'get big' and how are tsunamis different?
|
I just don't get how or why waves can be really calm somewhere and then suddenly can get to 50ft tall. Where does the water come from/go, and what happens to generate really big waves? What factors make some places really wavy?
|
Physics
|
explainlikeimfive
|
{
"a_id": [
"gn8u9gs"
],
"text": [
"Waves on the ocean surface are usually formed by wind. The faster the wind, the longer it blows, or the farther it can blow uninterrupted, the bigger the waves. Therefore, a wave's size depends on wind speed, wind duration, and the area over which the wind is blowing. Basically what happens is the wind blows over the water, changing its surface into ripples and waves. As waves grow in height, the wind pushes them along faster and higher. Waves can become unexpectedly strong and destructive. As waves enter shallow water, they become taller and slow down, eventually breaking on the shore."
],
"score": [
6
],
"text_urls": [
[]
]
}
|
[
"url"
] |
[
"url"
] |
lj4lvd
|
What makes different types of coffee taste different?
|
Chemistry
|
explainlikeimfive
|
{
"a_id": [
"gn90ova"
],
"text": [
"The three main things: Origin (location the bean was grown in), roast, and preparation **Origin**: Much like wine, where and how a coffee plant is grown is going to effect the flavor of the bean it produces. Coffee actually isn't grow in large quantities in too many places because the plant itself needs more specific conditions to grow well. A coffee plant from Brazil, Indonesia, or Kenya is going to produce different flavors in its beans. **Roast**: Coffee beans are roasted, the bean you take out is [green and raw]( URL_2 ). Essentially they are cooked before we consume them. For simplicity, we'll say there are three roasts, [light, medium and dark]( URL_1 ). A Light coffee means its lightly roasted. Its flavor will be bright have some zing, a little fruity and have a very \"coffee\" like taste. A dark roast will be robust, deep flavored, even chocolatey or toasty flavors. A medium is well, in-between both. **Preparation**: There are many ways to brew coffee and to grind it. Depending on the [size of the grind]( URL_0 ) and method of preparation you can extract more and different flavors from the ground beans. If you're just use to filter coffee, understand its only one of many ways to make coffee and using the same bean, with a different grind in a different method, may produce a substantially different flavor of final drink Preparation is incredibly important. Some fancy coffee places will have tastings where they take the same bean and prepare it different ways and you taste them all together and you can tell the difference."
],
"score": [
3
],
"text_urls": [
[
"https://imgur.com/NqNO9G7",
"https://imgur.com/TBIkmTQ",
"https://imgur.com/68fJvIh"
]
]
}
|
[
"url"
] |
[
"url"
] |
|
lj5mwq
|
if buildings don’t have a 13th floor, isn’t the 14th floor the 13th? or is there just an empty floor that no one can access?
|
Other
|
explainlikeimfive
|
{
"a_id": [
"gn98aat"
],
"text": [
"The number is often just skipped, and the sequence resumes with 14. I believe I have seen one building that used the 13th floor as a entirely mechanical floor, but that's also a rather unusual case."
],
"score": [
7
],
"text_urls": [
[]
]
}
|
[
"url"
] |
[
"url"
] |
|
lj6al1
|
How does a neutron bomb work?
|
Technology
|
explainlikeimfive
|
{
"a_id": [
"gn9iv5w",
"gn9pan7"
],
"text": [
"A modern nuclear weapon is usually a fission-fusion-fission design. That means you use a fission reaction to get enough energy for a fusion reaction and then use the neutrons from the fusion to get even more fission. That can give you a really *tremendous* kaboom in a smallish package. For a neutron bomb (aka an Enhanced Radiation Weapon) you skip the last fission stage. Instead of absorbing those neutrons and using them to make more kaboom you let them go screaming off into the world to fuck shit up. The benefit this gets you is that you get a relatively small (for a nuke) blast, with a relatively big deadly radiation distance. This is useful if the thing you are trying to kill is heavily resistant to blast effect (like a tank) or very hard to hit (like an incoming nuclear warhead). In practice the only actual deployment of neutron weapons was as anti-ballistic missile systems, because that's where they really shine.",
"In theory, a neutron bomb emits a blast of neutron radiation which incapacitates or kills all the people in the area leaving structures undamaged and minimal residual radiation so the attacker can quickly move in and secure the now vacant infrastructure In practice, it doesn't really. For anything bigger than about 10 kT the immediate blast radius is far greater than the radius of lethal radiation so they have to be made from very small devices. For a 1 kT \"neutron bomb\" the radiation would be 100% lethal in a couple days out to 900 meters and 50% lethal out to 1400 meters. Oh and this device would completely obliterate non-reinforced concrete structures out to 600 meters and would take out all wooden buildings to about 900 meters so only the area between 900 and 1400 meters out is kinda cleared of people and kinda not destroyed, inside 900 meters is pretty damaged and outside 1400 meters is relatively unhurt. The idea is based around the fact that both Uranium fission and fusion of tritium give off a fast neutron (turning the lithium fuel into tritium gives off another too) so you can have those neutrons deal with weak organics. The neutrons can also be used to trigger other near by nuclear devices (like an incoming hostile nuke) but similar to taking out meatbags, it has to be really really close to the target to do that reliably ( < 100 meters)"
],
"score": [
13,
5
],
"text_urls": [
[],
[]
]
}
|
[
"url"
] |
[
"url"
] |
|
lj736p
|
what is a race in biology and why humans cannot be classified with races? (besides ethical matters)
|
Biology
|
explainlikeimfive
|
{
"a_id": [
"gn9qebw",
"gn9re3c"
],
"text": [
"Race really isn't a scientific term. So, while there are regional variations in human genetics, and people whose ancestors come from one region are likely to have certain genetic traits, the idea that we can divide humanity up into distinct groups isn't really a scientific one. There's no clear cut \"These people have the Asian gene, and those people have the European gene\" going on. Any such division made is purely arbitrary, going \"I think those people are similar, and those people aren't.\" So there's no real science behind the concept of \"race\" as we use it in modern society.",
"It always bothered me whenever humans were regarded or described as a “race”. Human beings, or homo sapiens, are a species of animal on this planet. There are different variations of the species, but genetically all are identical. In biology race isn’t a word that exists to describe anything. There are species, variants on those species, and sub variants, and when a variant is considered different or established enough it is moved from variants of species status to full fledged species, all its own and classified as its own group. Race is only brought up by humans to describe other humans who are different on the surface than they are, even though honestly, any superficial differences are simply a variant inside the homo sapian species. Those variations can be passed on to the next generation at such and such probability based on dominant traits and submissive traits, but that’s all it is."
],
"score": [
9,
3
],
"text_urls": [
[],
[]
]
}
|
[
"url"
] |
[
"url"
] |
|
lj74ec
|
Silver metal value
|
Quick question, when and how was silver, once regarded worth as much as gold, went down to a sliver of that, and if it could rise again.
|
Economics
|
explainlikeimfive
|
{
"a_id": [
"gn9r108"
],
"text": [
"Silver is far more abundant than gold and much easier to extract and mine. We extract about 6x-8x more silver per year than gold. Modern Gold mining is actually really difficult, expensive and often environmentally damaging depending on the method. Silver is much easier to extract and we extract vast amounts more silver than gold each year."
],
"score": [
4
],
"text_urls": [
[]
]
}
|
[
"url"
] |
[
"url"
] |
lj7dpa
|
Why do we have to work out
|
Biology
|
explainlikeimfive
|
{
"a_id": [
"gn9xts2",
"gn9xr0o"
],
"text": [
"Other animals in the wild get workouts from hunting, gathering food, and escaping predators and seeking mates. Domesticated animals often have to have their food limited to prevent them from getting fat. Humans often eat diets which are higher calorie than they expend. The body stores most of that as fat. If you have a physical job that causes you to expend lots of calories you could consume more calories without getting fat. Exercise causes us to burn the calories which is basically stored energy and we lose weight because we've burned the stored energy. A diet limits extra calories and exercise burns calories so the body doesn't have to store it was fat. Exercise causes miniscule damage to muscles which as it heals creates more muscles to use. Using muscles over time creates more muscles. When not in use the body tends to absorb excess muscle making us weaker.",
"Humans have made their lives so easy they can get way more calories than they need with very little physical effort. Animals like deer are constantly walking to find food and running from predators, so they get that exercise naturally."
],
"score": [
7,
5
],
"text_urls": [
[],
[]
]
}
|
[
"url"
] |
[
"url"
] |
|
lj87dp
|
What exactly is the point of having rRNA?
|
Hello, so it's been a while since I read something about nucleic acids, but I don't think I've ever understood this. So the ribosomes are consisting of some rRNA and they are involved in translation and protein synthesis. I'm just wondering, what exactly the rRNA does. The function of mRNA and tRNA is pretty clear to me but I can't see how rRNA plays a role. What activity does it show?
|
Biology
|
explainlikeimfive
|
{
"a_id": [
"gna6z4y",
"gnb4zvr",
"gna7oj6"
],
"text": [
"rRNA might be the most important sequence of nucleotides in life. It is the actual functional unit that changes RNA into protein, quite literally the bridge from a DNA/RNA message into the proteins that life is further built up from.",
"I think it's best to remember that things in biology don't always have a reason, it's just the way it happened. In this case, it's now widely believed that RNA came before DNA and served as the sole carrier of genetic information for early life and performed catalytic activity, which is to say, it can fold upon itself and create things, including more of itself. Likely before there were proteins to provide the cell with enzymatic activity. One of RNA's catalytic activities is protein synthesis in a structure made of mostly rRNA (speaking to it's acient lineage) and some protein, called the ribosome or ribozyme (RNA with enzymatic function). DNA, with it's greater chemical stability and large proteins, with their vastly superior enzymatic activity, came some time later. DNA now serves as genetic storage while RNA, now copies of very small segments of the much larger DNA (genes), continues to serve as a unit of protein production (and many other roles).",
"During translation of mRNA, rRNA functions to bind both mRNA and tRNA. So here is an analogy- think of rRNA being a 3D printer or oven, where you put in the different ingredients/components (i.e the mRNA and tRNA) and you have a newly formed outcome/product"
],
"score": [
6,
6,
4
],
"text_urls": [
[],
[],
[]
]
}
|
[
"url"
] |
[
"url"
] |
lj8ji4
|
When TV's had no display and were a static screen (black and white dots), what causes the static sound?
|
Back in the day (mostly) when you had nothing plugged into your TV you would get a black and white static screen with a static noise. What causes the noise?
|
Technology
|
explainlikeimfive
|
{
"a_id": [
"gnagtfe"
],
"text": [
"Are you asking specifically about the sound? The sound and the pattern are two sides of the same coin. Normally, a TV would be receiving a signal of information for picture and sound. When there's nothing connected or the signal isn't good, the TV picks up on random bits of electromagnetic noise, like stray waves from a microwave, or something with magnets moving. About 1% of this stray noise is actually the remnants of the Big Bang. The TV does it's best to interpret this 'signal' and make a picture and the appropriate sound. But the signal is rubbish. Instead of being a clear patterns of 1s and 0s that make, say, a face and the sound of someone talking, they are totally random. So, you get splodges of light and dark, and a hiss known as white noise. This is the auditory equivalent of the 'snow' you see on the screen. Crucially, when the TV is properly tuned to a source, that noise (both visual and auditory) is still there. It's just that the real signal is so much stronger that it gets drowned out."
],
"score": [
3
],
"text_urls": [
[]
]
}
|
[
"url"
] |
[
"url"
] |
lj8uty
|
Why do we have more control over a drawing, sketch or digital design when we use pens instead of mice? Why are we less precise when using mice?
|
Biology
|
explainlikeimfive
|
{
"a_id": [
"gnaeo19",
"gnad5n2"
],
"text": [
"This isn't a generally true statement - especially not for people who have trained many years on the mouse. However most people learn how to write and draw using pencil and paper - so they would naturally have a higher control over a pen-like input initially. But spend a few years on CAD or drawing software and this is no longer always true. It is true, anatomically (for most people), that the muscles controlling the fingers are capable of finer control than say the wrist - also because your fingers have a lot of nerve endings which can detect pressure and motion feedback better. So a pen-like input is still superior for humans.",
"One motor neuron controls a few different muscle cells, the group of cells the control is called a motor unit. The smaller the motor unit, the more precise control you have (more neurons controlling fewer muscles, as close to a 1:1 ratio as you can get gives you more control). The small muscles in your hand have more precise control over fine movement than moving a portion of your arm usually when you use a mouse. The bigger the muscle usually the less precise control you have over it. There’s also the computer sensitivity to the mouse and non-biologic factors involved too. If you turned the sensitivity down, you would probably be able to be more precise with the mouse than with the sensitivity higher"
],
"score": [
9,
5
],
"text_urls": [
[],
[]
]
}
|
[
"url"
] |
[
"url"
] |
|
lj8waw
|
What is the Vigenère code?
|
There's been a post about this before but it didn't really help me so I'm still really confused. What is the Vignère code and how do you use it?
|
Other
|
explainlikeimfive
|
{
"a_id": [
"gnag0wb",
"gnaf1wt"
],
"text": [
"So we have to start from the basics and build out from there. One of the most basic kinds of *substitution cipher* is called the Caesar cipher, after Julius Caesar. In such a cipher, the letters in the plaintext message are shifted so many letters along. For example, in a Caesar cipher \"of shift 3,\" `A` would become `D`, `B` would become `E`, and so on, looping around if necessary. The letters are shifted 3 ahead in the alphabet. The Vigenere cipher is a modified, layered form the Caesar cipher, where each letter of the plaintext is shifted, much like as in a Caesar cipher -- *but the number of letters each letter is shifted is different.* To do this, you would make a 26-row table, called a Vigenere square. Each row would contain the alphabet, but starting from a different letter: ABCDE... BCDEF... CDEFG... and so on. You would also select a *key word,* which can be whatever you like; the longer the better. For each letter in the plain text, you would take the corresponding letter in the key word, and look at that letter's row. Then, you would look for the column whose number matches the letter you're encoding: the second column for `B`, the third column for `C`, and so on. The encoded letter is found at the intersection of row and column, and this process is repeated for the entire plain text message, beginning again at the start of the key word as necessary.",
"It is a polyalphabetic cipher. First, think of a keyword, like EARTH Second, come up with the phrase you'd like to encrypt, like HELLO WORLD You write out your message and then the key word underneath, repeating the keyword as necessary: |H|E|L|L|O|W|O|R|L|D| |:-|:-|:-|:-|:-|:-|:-|:-|:-|:-| |E|A|R|T|H|E|A|R|T|H| For the next part it's often better to treat the letters as numbers (A=0, B=1, C=2, ... Z=25) |7|4|11|11|14|22|14|17|11|3| |:-|:-|:-|:-|:-|:-|:-|:-|:-|:-| |4|0|17|19|7|4|0|17|19|7| Then you add the numbers in each column together. If you get a number greater than 25, you reduce it by 25 (e.g. 11 + 17 is 28, but you reduce it by 25 to get 3) |7|4|11|11|14|22|14|17|11|3| |:-|:-|:-|:-|:-|:-|:-|:-|:-|:-| |4|0|17|19|7|4|0|17|19|7| |11|4|3|5|21|1|14|9|5|10| Then convert back into letters: |H|E|L|L|O|W|O|R|L|D| |:-|:-|:-|:-|:-|:-|:-|:-|:-|:-| |E|A|R|T|H|E|A|R|T|H| |L|E|D|F|V|B|O|J|F|K| So your final encrypted message is LEDFVBOJFK"
],
"score": [
6,
3
],
"text_urls": [
[],
[]
]
}
|
[
"url"
] |
[
"url"
] |
lj91ov
|
How does an electron neutralize the charge of a proton when the electron is so much smaller?
|
Basically, what it says on the tin. Okay so the proton is big enough to contribute to the atomic weight but the electron doesn't. How in the world does the electron neutralize the proton when it's so much smaller? I feel like it has something to do about the speed of the electron maybe
|
Physics
|
explainlikeimfive
|
{
"a_id": [
"gnafb2j",
"gnazvtp",
"gnagpwe"
],
"text": [
"Because charge and mass are two different things. It's the charges that cancel between the two as they have equal and opposite charge. The masses, however, are very different.",
"Charge and mass are two completely independent properties. I could ask why my truck weighs more than a basketball despite the fact that a basketball is orange, but color and weight are two completely independent things.",
"It does not neutralize the charge like an acid neutralizes base. Charge defines the type of behavior it will have in the presence of other negative and positive charges. Opposite charges attract but when they come together its not like they become neutral (if they did then they wouldnt be attracted any more)"
],
"score": [
8,
7,
5
],
"text_urls": [
[],
[],
[]
]
}
|
[
"url"
] |
[
"url"
] |
lj99yv
|
What differs in the decomposition process of a human body when it's in the water compared to when it's on ground in contact with air etc.
|
Biology
|
explainlikeimfive
|
{
"a_id": [
"gnawsi9",
"gnahhxb"
],
"text": [
"If you want to learn more about it, there’s a fantastic book by Mary Roach called “Stiff; the Curious lives of Human Cadavers.” It explores many of the ways our bodies are disposed of when we’re done with them.",
"Can I kindly ask why do you want to know?"
],
"score": [
6,
3
],
"text_urls": [
[],
[]
]
}
|
[
"url"
] |
[
"url"
] |
|
lj9o5m
|
Why does it help the pain when you rub or hold that area?
|
Whenever you hit your body part, it’s painful. But rubbing that area makes the pain more bearable. What is the reason for that?
|
Biology
|
explainlikeimfive
|
{
"a_id": [
"gnany51"
],
"text": [
"Your nerves can only send one type of signal at a time. Pain, temperature, touch pressure. They have a hierarchy and pressure gets the highest signal priority"
],
"score": [
11
],
"text_urls": [
[]
]
}
|
[
"url"
] |
[
"url"
] |
lj9yl5
|
What is at the bottom of the crack in an earthquake?
|
Earth Science
|
explainlikeimfive
|
{
"a_id": [
"gnbkvdu",
"gnbm45n"
],
"text": [
"if you drop a layer cake, one or more layers may break, but not always in the same place. what is happening is the soft layer of filling keeps the breaks seperate. so where the topping or icing breaks, you may get a deep chasm, you may not, but unless the cake is completely unrecognisable, there's not a single place where you see all the way to the plate. the earth's crust is made of many more layers of all different softnesses. wherever they get squished or stretched, an earthquake is the vibration of the layers moving around and rubbing. so there is not always a break, and just like the dropped cake, you might get lucky and the change in shape might not be noticable! when there is a break you will likely see the crack go down through rocks of similar softness, until a layer of softer or loose rocks, perhaps covered by loose rocks fallen in from the sides of the crack. if you were expecting a volcano to burst out, you would have to be next to a geological fault line, where the process is different. that's more like two cakes being smooshed into each other, and the cracks and earthquakes are usually minimal compared to the slow movement of layers sliding and folding over each other, leaving filling all over the place and very occasionally letting some of the super hot filling of the earth to leak out. please clean up after yourselves and don't waste cake.",
"Essentially just more rock or earth. The crack narrows as it goes deeper and eventually the two sides meet. It's not like cracking a piece of glass where it goes all the way through. It's more like a crack in the asphalt on the road; at the bottom of the crack is just more asphalt, or at least whatever dirt or material is underneath it."
],
"score": [
22,
6
],
"text_urls": [
[],
[]
]
}
|
[
"url"
] |
[
"url"
] |
|
lja3bc
|
If caffeine blocks adenosine receptors to make us feel less tired how does it make us less tired when there's already adenosine prior to blocking?
|
Normally when I take caffeiene in the middle of the day I still feel much less tired yet haven't I have already built up adenosine that doesnt go anywhere after I take the caffeiene? Wouldn't caffeine just prevent future tiredness rather than increase my current energy?
|
Biology
|
explainlikeimfive
|
{
"a_id": [
"gnatmb0"
],
"text": [
"Without getting into the far more complex effects of caffeine than those on adenosine receptors, I'll just answer that question taken out of context. Caffeine is a competitive antagonist for the adenosine receptors. So if you have let's say 100 arbitrary units (AU) of adenosine and no caffeine, then you get 100 receptors activated. If you have still have 100 AU adenosine, but also have 100 AU caffeine, then assuming equal affinity (likely isn't true but doesn't matter for the explanation), that means there are probablistically 50 receptors activated only, because caffeine and adenosine compete for the same receptors. It doesn't matter that adenosine didn't go away from the system, what matters is how many receptors are activated. Let's say you do this for hours, then eventually adenosine accumulates and caffeine does too from frequent intake, if you stop taking caffeine (negating the half life of either ligand), you suddenly have much more active adenosine receptors giving a crash."
],
"score": [
7
],
"text_urls": [
[]
]
}
|
[
"url"
] |
[
"url"
] |
ljat8z
|
As we grow old, why does the rest of the body deteriorate so much faster than the brain?
|
People in their 70s can't generally compete with a twenty-something when it comes to physical prowess: speed, strength, reflexes, coordination, etc. The deterioration of the body is obvious. However, when it comes to the intellectual dimension, it's not that rare to find old people who have remarkable mental capacities, be it problem solving skills, reasoning, wit, etc. If the brain is just another organ, how come it seems to retain its capacities way beyond the level of the rest of the body?
|
Biology
|
explainlikeimfive
|
{
"a_id": [
"gnb8bme"
],
"text": [
"It does deteriorate. Performance on simple mental tasks peaks in the 20s and 30s, then slowly declines for the rest of life. But unlike the body, the mind learns and saves ideas it has seen before. People who are older have more experiences to draw on, more background knowledge, more ready-to-go ideas and structures. So on *complex* tasks that require a lot of groundwork, people can continue to progress at a rate that outpaces the general decline of their brain for many decades. The individual steps in their brains are slower and more error prone, but they have to make fewer steps because they've already *done* many of them."
],
"score": [
16
],
"text_urls": [
[]
]
}
|
[
"url"
] |
[
"url"
] |
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