q_id
stringlengths 6
6
| title
stringlengths 3
299
| selftext
stringlengths 0
4.44k
| category
stringclasses 12
values | subreddit
stringclasses 1
value | answers
dict | title_urls
sequencelengths 1
1
| selftext_urls
sequencelengths 1
1
|
|---|---|---|---|---|---|---|---|
7f2pb7 | Why haven't we found a cure for cancer yet? | Biology | explainlikeimfive | {
"a_id": [
"dq920of"
],
"text": [
"we've found cures for many forms of cancer, but its more of a category than a single disease, and its not really a foreign infection/virus, its just misbehaving cells. So that makes it hard to kill the cancer and not kill the rest of the body."
],
"score": [
6
],
"text_urls": [
[]
]
} | [
"url"
] | [
"url"
] |
|
7f2puk | What is an elliptical orbit? | From what i understand it is some kind of orbit around two points, but I'm hoping for a simple explanation and maybe an example of how they would affect manoeuvres in a low or high orbit, or even combat manoeuvres - or is that too speculative? Thanks in advance | Physics | explainlikeimfive | {
"a_id": [
"dq92p3e"
],
"text": [
"All orbits are elliptical. Ok not all, but in the simplest orbital mechanics even circular orbits are elliptical. It's not about orbiting two bodies, it's about the shape of the orbit. An ellipse is a shape made by a curve traced such that at every point the sum of the distances from two given points (the locii) are equal. Another way to think about it is as a section cut out from a cone. For this reason sometimes orbits are sometimes approximated as conic sections."
],
"score": [
6
],
"text_urls": [
[]
]
} | [
"url"
] | [
"url"
] |
7f2qpx | why when looking at a certain point without blinking for few seconds you start seeing double? | Biology | explainlikeimfive | {
"a_id": [
"dq93e1s"
],
"text": [
"Not everybody sees double. If you do, it is probably because your eyes get tired and stop looking in exactly the same direction. This is technically known as a strabismus."
],
"score": [
4
],
"text_urls": [
[]
]
} | [
"url"
] | [
"url"
] |
|
7f2qyp | Vector components? | Hi Basically, I know what vector is. But i really don't understand what vector component is? Is it just another word for vector?? Could someone please explain this | Mathematics | explainlikeimfive | {
"a_id": [
"dq930rk"
],
"text": [
"A vector *component* is just one of the dimensions of the vector. Say you have a vector V, and V is composed of < x,y,z > . X, Y, and Z are components of V. In the same vector V composed of < 10, 5, 1 > , the x-component has a magnitude of 10, the y component has a magnitude of 5, and the z component has a magnitude of 1. EDIT: It might make more sense if we phrase this in the context of addition. When adding two vectors, their components add. So, if V = < 10, 5, 1 > and U = < -10, 5, -1 > , V + U = < 10 + -10, 5 + 5, 1 + -1 > = < 0, 10, 0 > ."
],
"score": [
14
],
"text_urls": [
[]
]
} | [
"url"
] | [
"url"
] |
7f3b14 | Why does ejaculation feel better the longer you last? | Biology | explainlikeimfive | {
"a_id": [
"dq98aq5"
],
"text": [
"I'm no scientist but surely it's just delayed gratification at its purest form. It's just the same as being at work the whole day and thinking about the chocolate cake you've got at home. Then after a 10 hour shift, you finally get to go home and eat the cake. It instantly tastes so much better than just buying a cake and eating it immediately."
],
"score": [
3
],
"text_urls": [
[]
]
} | [
"url"
] | [
"url"
] |
|
7f3hcy | What percentage of wild animals die of old age? | Biology | explainlikeimfive | {
"a_id": [
"dq9b0qj",
"dq9b1y6"
],
"text": [
"It's a difficult, if not impossible, question, I'm afraid! The reason why is because nothing really dies of 'old age' *per se*. Rather dying of 'old age' in animals, including ourselves, is really dying from ailments associated with senescence and whose risk increases with lifespan; say organ failure, or cancer, or contagious disease successfully laying siege upon an older and aged immune system - and these factors can happily take you out at *any* point during your life. These age-associated problems also mean wild beasties are more likely to be picked off by predators or fail to keep themselves sufficiently nourished, so in many respects, dying of 'old age' *is* often dying from, say, starvation (that is, if you were lucky to escape the notice of the lions during your increasing malnourishment!). Saying that, there are some figures I can give you on some age-associated diseases that may be of interest. So I'm a zoologist researching cancer in natural mammal populations (specifically whales and other big things), and it's interesting to note that fatal cancer incidence scales across mammals with body size and longevity - the smaller you are, the more likely it is you'll die from cancer during your later years, and vice-versa. For example, for those individuals that live to within 20% of their expected maximum lifespan in the wild, about [50% of mice]( URL_2 ) will succumb to cancer (i.e. of those that dodge owls successfully and survive to at least 2+ years), as do about 30% of chimpanzees, [3% of elephants]( URL_0 ) (most starve from tooth decay) and about 5-10% of beluga whales\\*. But yeah, dying from cancer is pretty rare; again, across entire lifespan, you're most likely gonna' be picked off by something bigger, or starve, even (and especially) if you're inevitably losing the war against parasites and disease over the years. \\* Unless they're from the St. Lawrence estuary, which is heavily polluted. There, about 18% die from cancer, alongside 22% from respiratory and gastrointestinal infections with metazoan parasites, and 17% from bacterial, viral, and protozoan infections ([source]( URL_1 )). ____ **EDIT:** Oops, thought this was r/AskScience. Sorry for a not-quite-ELI5 answer! No doubt someone else'll better explain things in a more digestible format.",
"Nobody dies of old age. As you get older your immune system gets weaker and weaker and your cells have a harder time healing. When you die of old age it usually means one of your major organs finally failed after years of getting weaker and wear and tear. I don’t how you can differate between an old animal dying or something specific like a heart attack and something vague like old age."
],
"score": [
15,
3
],
"text_urls": [
[
"https://jamanetwork.com/journals/jama/fullarticle/2456041",
"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC1240769/",
"https://www.ncbi.nlm.nih.gov/pubmed/12004924"
],
[]
]
} | [
"url"
] | [
"url"
] |
|
7f3nx3 | How is it that an asteroid which is not even 1/1,000th the size of the earth can still manage to cause extreme damage or extinction if it hit our planet? | Physics | explainlikeimfive | {
"a_id": [
"dq99iz6"
],
"text": [
"How does a bullet which is a fraction of the size of a human cause so much damage? Our existence on this world is dependant on a lot of different factors, and if you change them too much it wipes out a lot of life (but probably not all) When an asteroid hits the earth the immediate area is devastated, but what it also does is through lots of dirt and dust up into the atmosphere. Those further away are fine to begin with, but all this dust blocks some of the light and heat from reaching the surface. This induces a mini ice age in which the planet cools down. Now whilst on the grand scheme of the lifetime of the planet this wont do too much, if you happen to be living on the planet when it happens your gonna have a bad time. At first its ok, but then as it gets colder certain plants start to die off because its too cold for them. Any animals that eat those plants are then going to struggle and their numbers will dwindle. That then means there are less animals for the hunters to eat and so they start to struggle. All of this has a huge knock on effect that kills of entire eco systems. Back to my first statement \"How does a bullet which is a fraction of the size of a human cause so much damage?\". The bullet itself only devastates the immediate area, however if it hits a major organ the entire system will eventually fail, or you might bleed out etc. End result is the same. There are many other ways it can be devastating, its just one example EDIT: Clarified a few points."
],
"score": [
8
],
"text_urls": [
[]
]
} | [
"url"
] | [
"url"
] |
|
7f3wv0 | Why do ant's releases some kind of bad smell when you kill them? | Biology | explainlikeimfive | {
"a_id": [
"dq9dq1b",
"dq9by9y"
],
"text": [
"It's only *some* ants! And, depending on the species, there are two possiblities: i) You could be releasing a small burst of formic acid produced by ants from the subfamily [*Formicinae*]( URL_3 ), including the common 'wood ants' you find in your garden. The stuff gives off an acrid smell, very similar to < 5% acetic acid or vinegar, which they use to help [repel nosy predators]( URL_0 ) and defend their nests. ii) Alternatively (well, in what's almost *certainly* the case), you're encountering the so-called odorous ant ([*Tapinoma sessile*]( URL_2 )), which are commonly found across the US and Canada, and are notorious home invaders. These beasties incorporate methyl-ketones into the scent trails they use to communicate and, as u/Elfere pointed out, crushing 'em releases all these signalling compounds at once, giving you a pungent whiff! There was a fun [study]( URL_1 ) published a few years back attempting to determine what these trails actually smelled like. They're apparently said to smell like rotten coconut, but a scientist at NCSU thought it was more like blue cheese, and proved it. By filling different containers with ants, cheese n' coconut, and analysing the gasses produced, they discovered the methyl-ketones present in the ant odour was shared by the ripe bit o' blue, but not the coconut. Though, in a follow-up trial, by digging up some buried 'nuts left in the garden for a fair bit, they also found that the *Penicillium* mould growing on the rotting coconut also produces the same ketones, albeit to a lesser extent. So, err, everyone wins? In any case, they smell. It's worth noting the vast majority of other ants produce signalling molecules that aren't particularly detectable by our olfactory system however, which certainly helps when trying to ID the buggers you got on your desk. In short, you got odorous ants.",
"Sim ant told me that ants use phenomenons as markers. They basically 'talk' with smells. Kinda like dogs but even more so. So when you crush them. You're releasing ALL their smells at once. To other ants it means OMG SOMETHING HORRIBLE HAPPEND HERE. And now you know ."
],
"score": [
6,
3
],
"text_urls": [
[
"https://www.youtube.com/watch?v=Sp8b1vVnQSY",
"https://academic.oup.com/ae/article/61/2/85/1756864",
"https://en.wikipedia.org/wiki/Tapinoma_sessile",
"https://en.wikipedia.org/wiki/Formicinae"
],
[]
]
} | [
"url"
] | [
"url"
] |
|
7f4kfz | Why is the FCC not worried about causing international incidents if American ISPs throttle international websites/apps/services? | Other | explainlikeimfive | {
"a_id": [
"dq9g0z4"
],
"text": [
"Other nations already do it and nobody cares, so international precedent has been set. China outright blocks most of them and nobody cares."
],
"score": [
3
],
"text_urls": [
[]
]
} | [
"url"
] | [
"url"
] |
|
7f4wof | Why does black-top (AKA asphalt, tarmac, macadam, etc) fade from black to gray? | Which of these possible reasons causes black-top roads to change from black, when freshly paved, to gray? * Simple wear of the top level of tar to expose the gravel. * Evaporation of the tar due to sunlight and weathering. * Biologic erosion by tar-eating microbes. * Other?? | Chemistry | explainlikeimfive | {
"a_id": [
"dq9irra"
],
"text": [
"They get covered in dust. There is an anormous amount of road/tire dust deposited from passing vehicles and the environment, and that dust gets repeatedly smushed into the roadway. Its really just a lot of dust. EDIT: so option D, other"
],
"score": [
5
],
"text_urls": [
[]
]
} | [
"url"
] | [
"url"
] |
7f51sj | How do the ridges and bumps on a record translate to the music we hear? | Technology | explainlikeimfive | {
"a_id": [
"dq9l4i5",
"dq9lfwt",
"dq9lhwm"
],
"text": [
"Talk means sound Sound means vibration in the air Vibration is little wiggles (think of glass shaking on a plane) If you put those little wiggles through a needle onto a surface that's soft, the surface will keep a \"record\" of the little wiggles. Next, harden the surface with the wiggles on it. Put the needle back on the wiggly surface except this time have the pattern of the wiggles coming through the needle be amplified out. Voila, a record.",
"What I don't understand is how we can record audio if everyone has a unique voice? How is there enough variation in the waves/trough to record every unique sound?",
"Imagine a speaker playing music. The cone goes in and out to make the sound. Now, imagine attaching a needle to the base of the cone so that it also moved in and out. Now imagine dragging sheet of wax under that needle. You would be left with a bumpy groove that exactly describes where the base of the cone was at each instant in time. If you could somehow freeze that and drag it under the speaker again at the same speed, the cone would move back and forth exactly the same way it did while it was creating the recording. This is exactly how records were created and played originally (except that they didn't really have speakers...the needle was attached to a diaphragm and the amplifier was just a big horn). Eventually to improve dynamic range and amplification, they replaced the diaphragm with a magnetic coil which actuated another magnetic coil in the speaker. This, in turn led to stereo where instead of one bumpy track at bottom of the groove, they could have two tracks on the sides of the groove."
],
"score": [
47,
6,
4
],
"text_urls": [
[],
[],
[]
]
} | [
"url"
] | [
"url"
] |
|
7f533t | If you're travelling at the speed of sound, will your voice be delayed if you spoke? | Physics | explainlikeimfive | {
"a_id": [
"dq9k87i"
],
"text": [
"No. Sound is not a physical object, or an energy field. It is a regular movement of air, like trembling wind. How fast it moves is governed by how far a molecule can tremble before it makes the one next to it tremble, so that it's faster in thick mediums like water, and slower in thin mediums like air. Because all of the air that's trembling on the ISS is also being moving really fast, the distortion behaves like the entire ISS is perfectly still. If you were in a convertible car going the speed of sound, your voice would still move at the speed of sound in all directions. If you're passing by me and say 'hello', I'll hear the split second you're passing me at the normal speed and volume. But the sound of your 'hello' will all be stuck right in front of you from your perspective while you chase it as fast as you can go. This builds up over time with stronger and stronger vibrations until it causes a 'sonic boom', shredding outwards in all directions as you pass in front of the sound. But again, it's not that it's delayed, it still arrives in the same amount of time no matter what you do. It's just that you might arrive before it. Though if you were talking to someone in the front seat from the back, they would never hear you until the car slowed down."
],
"score": [
5
],
"text_urls": [
[]
]
} | [
"url"
] | [
"url"
] |
|
7f57a2 | Why does it hurt like hell when you burp through your nose? | Biology | explainlikeimfive | {
"a_id": [
"dq9lx95"
],
"text": [
"If you were burping from a carbonated drink, it hurts because some of the drink become aerosolised and enter your nose, and the carbonic acid hurts your nose. Alternatively, it could be your stomach acid that's getting into your nose."
],
"score": [
3
],
"text_urls": [
[]
]
} | [
"url"
] | [
"url"
] |
|
7f591g | How does the human ear discern between a quiet noise and a distant noise? | Biology | explainlikeimfive | {
"a_id": [
"dq9m5ww",
"dq9ppfy",
"dq9tdif",
"dq9utu9",
"dq9ltl6",
"dq9v7p0",
"dq9yya9",
"dq9mqs1",
"dqa1rt7"
],
"text": [
"A quiet noise from a nearby source will have more high frequency content than the same noise made much louder from far away. This is because air absorbs high frequency sound energy over distance but not low frequency to the same extent (think about how a plane sounds low and rumbly from far away, but when you are close, it sounds like all of the frequencies). Additionally, nearby sounds will create stronger reflections off of surfaces close to you, creating a more full sound compared to distant sounds which will most likely consist of just one apparent location, or the reflections will be recognized as an echo, another indication that the sound is a large distance away. If you are not near any other objects, the first effect will be the predominant way your ear/brain make the distinction.",
"Interaural arrival times (sound arriving in on ear slightly before the other), interaural spectral differences (the fact that your head casts an acoustic shadow and blocks high frequencies will help you determine which direction it's coming from and how far away it is, less of an acoustic shadow means the sound is closer) and interaural intensity differences (sound from farther away will be louder in the ear facing it, whereas this difference will be less pronounced in a sound that's close).",
"In the study of audio engineering the terminology that we use is interaural time difference and interaural level difference. It refers to the sound hitting the ears at different times and at different amplitudes. The first order reflections of a sound source bouncing off of surfaces between the listener and the source will collect carry and transmit information to the listeners brain about the location of the source. If you listen to a loved one who is in your childhood home over the phone you might be able to tell which room your family member is standing in simply by the pattern of first order reflections.",
"I'd like to add to the top answers that your ear doesn't; your brain does. Your ear is just a microphone that translates vibrations into a signal (nerve pulses in this case, electrical current in the case of an actual microphone) that your brain (or computer) can work with. Your brain (or computer) then processes it and judges what is the case and not.",
"A distant noise sounds more echoey because it is accompanied by a lot of reflected sounds on its path to you, whereas a quite sound close to you is more direct. For very close sounds, another cue is that the sound has different angles to you ear. Whereas an infinitely distant sound arrives at your ear at the same angle, closer sounds become more different, and your ear can pick up that difference. Additionally, the sound is louder to the closer ear, more than expected of distant sounds.",
"Audio expert here. Didn't read any other comments, so this may have been answered already. In terms of decibels (also referred to as volume, or the intensity of sound), a distant noise could measure the same as a quiet, nearby noise. The difference is that through evolution, we've learned to pick up on the fine nuances between the two. Nearby sounds will tighter reflections (echos) off the walls and surfaces around us. Far away sounds, that were loud when produced but have gotten quieter as they reach us, are filled with reflections that are greater spaced. A sharp \"bang\" 1/2 mile away will trail with echos a lot longer than a nearby snap, though both may have the same decibel rating. Also note that over distances, low frequencies travel further than high frequencies. That's why when you hear a helicopter close up, you can detect the high-pitched whine of the turbine very easily, but seeing a helicopter in the distance, you only hear the low pounding of the blades. Knowing this, our brains automatically can decipher how far away something is, especially when we know what it sounds like nearby.",
"I don’t know it has been said like that but we use three different things to tell an audio source - Inter-aural time difference (ITD): since a sound is travelling around our head it takes it slightly longer to reach the ear that’s further away to the sound source - Inter-aural intensity difference (IID): for the same reason, the sound arrives to the ear that’s further away from the sound source with a lower amplitude - Inter-aural spectral difference (ISD): the shape of our outer ear, the pinna, does the rest. Additionally, it’s important to know that a sound from closer distance will have more high frequency content. Everything together is helping us locating a sound source. EDIT: Spelling.",
"Just to add to what's already been said. I think we can agree that the outer ear (penna) is weird looking. These bumps and ridges are important though because they bounce sound around the ear. We are able to detect if a noise is above or below us this way.",
"The better question is, why do emergency sirens (cops/EMTs/firetrucks/etc) sound like they're coming from all directions."
],
"score": [
6451,
206,
29,
22,
22,
20,
16,
11,
5
],
"text_urls": [
[],
[],
[],
[],
[],
[],
[],
[],
[]
]
} | [
"url"
] | [
"url"
] |
|
7f59wh | What happens in our body that makes us feel lonely? | Biology | explainlikeimfive | {
"a_id": [
"dq9lkay"
],
"text": [
"That sounds like a panic attack triggered by realising your loneliness. Loneliness in itself isn't associated with your described physical symptoms. On the other hand, panic attacks are caused by an acute activation of your sympathetic nervous system, commonly called the \"fight or flight\" response to stressors. The sympathetic nervous response includes increased heart rate and blood pressure, sweating, muscle shake, stopped digestive activity, and dry mouth. In panic attack disorders, the sympathetic response is severe and sustained, driven by perceived threats rather than real physical ones. ELI5: You were scared by being lonely."
],
"score": [
9
],
"text_urls": [
[]
]
} | [
"url"
] | [
"url"
] |
|
7f5nbd | How come taking an extended break from something sometimes makes you come back to it stronger than ever? | So for example, I didn't play tennis for months, and when I played again, it was the best I ever played. Even with a game. A FPS shooter, I took an extended break, came back, and won lots of matches over many veteran players. Why is this? Thanks! | Other | explainlikeimfive | {
"a_id": [
"dq9nubf",
"dq9nrb0",
"dq9srct",
"dq9qwqx"
],
"text": [
"Overthinking interferes with muscle memory. Taking a break can clear your head, so you’re back to playing on instinct. [Here’s a related article on why overthinking can make you choke]( URL_0 )",
"Most likely confirmation bias. Could also be that you're having more fun, increasing your performance.",
"My view on this is that we pick up bad habits when we play repeatedly. Taking a break lets us forget those. I get this in lots of things, but especially pool.",
"I believe that especially in the male brain (which tends to focus on one subject for extended periods of time), overexposure to an activity can make it less desirable over time. After a break, especially if you are holding yourself back from playing, you begin to want to play again with an aggressive tilt where you think a little faster while simultaneously tossing out old habits developed from muscle memory. If you play frequently, you will develop natural habits (both good and bad). Personally, with video games and with soccer, my bad habits usually revolved around my eyes becoming lazier and not focusing on the target. Eventually I would be mentally exhausted and unable to properly focus. A good sleep can help fix this, but it was always better to wait at least 24 hours or even 48 hours before trying again. Like when studying and working, if you are playing a game, you should take a break every 30 minutes to give your brain/muscles a rest. A longer break can yield better results. When you develop a good habit that is rewarding, it will stick with you much longer than a bad habit that almost never rewards you. This is why taking a break is often helpful; you will likely forget the bad habits and keep the good ones (remember it takes time to develop initial habits in the first place)."
],
"score": [
11,
5,
3,
3
],
"text_urls": [
[
"https://www.google.com/amp/s/www.psychologytoday.com/blog/the-athletes-way/201308/why-does-overthinking-cause-athletes-choke%3famp"
],
[],
[],
[]
]
} | [
"url"
] | [
"url"
] |
7f5v5e | Why do people wake up very early in the morning on every weekday to go to work, school etc. but sleep through to very late times on weekends and holidays, regardless of what time they begin sleeping? | Other | explainlikeimfive | {
"a_id": [
"dq9owzq"
],
"text": [
"They are required to get up for work and school and so do not actually sleep as much as they want/need to sleep. But they do sleep to the natural point of waking when they have nothing forcing them to get up."
],
"score": [
3
],
"text_urls": [
[]
]
} | [
"url"
] | [
"url"
] |
|
7f69ma | What is Dwarf Fortress and why it is made difficult? | Other | explainlikeimfive | {
"a_id": [
"dq9r0om"
],
"text": [
"**Long response incoming because I love this game.** > why it is made like this Dwarf Fortress is made by one person (Toady), with some help from his brother. Simply put, in Dwarf Fortress you embark with a small band of dwarves, which you carefully manage as you construct a suitable fortress. The fortress will be attacked by unpredictable, randomly-generated monsters, and your dwarves will start problems too. They might refuse to work when their friends die, sabotage things when they're upset, or even attack other dwarves. Toady's explicit goal with making Dwarf Fortress is to create an incredibly detailed game that tells unique stories every time. This means that all of his development effort (which he does for free) goes towards detail and emergent story-telling, not graphics. There are mods that replace the ASCII with \"graphics,\" so it's not his concern. When the game is simulating combat down to each individual finger and randomly generating so many things, modern visuals aren't viable. **In fact it's so complex that not even Toady can predict what will happen**. There used to be a famous bug where Toady couldn't determine why cats were constantly getting drunk. It turned out that they were walking around the beer-soaked dining halls, recognizing that their paws were dirty, and licking them. The bug was that these cats were getting a full \"dose\" of beer from their paws each time rather than just a little bit. > and difficult to understand Dwarf Fortress is hard to learn because of both the UI and aforementioned level of detail. Not only are the menus covered in dozens of hotkeys that have to be memorized, but there's also a lot of detail in management. You can't just tell the Dwarves \"make food here\" -- you have to specify which crops to grow each season, where to store the seeds and produce, which Dwarf should be in charge of farming, etc. People get discouraged because there's a lot of work that goes into learning the basics, **plus** you've got all the random bad stuff happening. You're trying to figure out hotkeys and how to create a basic farm layout, but your designated farmer is now throwing a tantrum and starving himself to death because he hates the job he's best suited for. DF actually isn't very difficult once you get over that learning cliff, but most people don't make it. It's a game that requires numerous failed attempts just to learn the basics. Even once you've learned how to play effectively, you're still going to lose a lot -- only now in spectacular fashion."
],
"score": [
67
],
"text_urls": [
[]
]
} | [
"url"
] | [
"url"
] |
|
7f6hs7 | What is Artificial neural networking? | Trying to do a presentation for college. Can't make sense of the topic. | Technology | explainlikeimfive | {
"a_id": [
"dq9srwy"
],
"text": [
"Neural networks are a software based problem solving tool that are inspired from how the brain works. Brains are made of neurons, which are connected to each other to send electrical signals. Each neuron makes a small change to the signal before passing it on and somehow eventually the signal becomes the answer. Neural networks are like that. They are made by arranging a large numbers of really small programs in a network. Each small programs can only change the answer it got from another small programs in a tiny way. So you start with a lot of presolved question answer pairs. Things like (2,2 =4), (1,4=5)....etc. and now you make the tiny programs modify what they will do to their answers again and again millions of times until you start getting the right answer. This is called the 'training' stage. If all goes well, the network of small programs will end up such that even when you give it a question it never saw before (1,3?) , It will come up with the right answer (4). The neural network has *learnt* addition. Even though you didn't exactly tell it to add, whatever the tiny programs have ended up doing, the net result is that they do addition. This becomes really useful for complex problems when we have only question answer pairs but have no idea how the answers are derived from the questions. Like how the temperature and wind are related to storms. Neural networks pick up patterns in such problems (even if we don't see them) and give us the right answer."
],
"score": [
6
],
"text_urls": [
[]
]
} | [
"url"
] | [
"url"
] |
7f6hyc | Why americans that failed go to “their parent’s basement” instead of their old bedroom? | Other | explainlikeimfive | {
"a_id": [
"dq9sjvu",
"dq9s1yi",
"dq9t4mo",
"dq9san0"
],
"text": [
"Because it is relatively common for people to re-purpose a basement into an apartment of sorts, and in the case of a young adult doing this in their parent's homes, it provides a modicum of independence while still relying completely on one's parents.",
"When kids leave home, parents generally repurpose the old room, making it a den or workspace. When an adult child comes back home, the basement would often be easier to make into a living space. Also, by making it a less than ideal situation, many parent would hope to make it a shorter stay",
"Because the basement (assuming it's clean, dry and finished) is closer in size to a proper apartment than the typical American bedroom. Since the endgame for both child and parent is to get the child back out and on their feet, you need a space for all the stuff they picked up along the way (bed, other furniture, kitchenware, electronics, etc.) which would be redundant in the house proper. By letting them build a living space in the basement, you save the hassle and expense of paying for separate storage. And as others have noted, A) parents typically don't preserve a child's bedroom after they leave the nest, so going straight back in probably isn't and option, and B) the basement would be desirable for the greater sense of independence and privacy.",
"This idiom is a throwback to earlier American culture, in which shameful children would be kept \"out of sight and out of mind\" in the basement if they were incapable of fitting into society. They wouldn't be allowed to leave the house, they wouldn't join the family at mealtime, and the neighbors would never see them. This was to reduce the amount of social pressure from neighbors and other members of society. This included mentally and physically disabled children, as well as those with mental illness. America used to segregate the disabled. We've moved on from that particular part of history, but the idiom has stuck around and now applies to any adult living at home that is not socially adapted. It should be noted that more and more families are choosing to allow their children to live at home into their 20's as a way of easing their progress into society after turning 18, usually during/shortly after college. This reduces their out-of-pocket cost for education significantly (no rent/no grocery bills/no utility bills), and can be a major help until they find a job they can use to sustain themselves."
],
"score": [
10,
9,
5,
3
],
"text_urls": [
[],
[],
[],
[]
]
} | [
"url"
] | [
"url"
] |
|
7f743l | Where does the internet come from? | Technology | explainlikeimfive | {
"a_id": [
"dq9v5o8",
"dq9vtok"
],
"text": [
"The internet is a network - thus the name. Its devices from all over the world connected by cables basically (some by wifi signals but only locally), some of which are servers (hosting content) and some are clients (accessing content) or a combination of both. You can become a service provider for example by providing space/servers to host data (cloud service providers, for example), or by selling access (aka cables) to end users. How you become an ISP also depends on where you live and how the market is or isn't regulated by your local government.",
"Your ISP buys their internet service from a larger ISP in bulk and splits it across all their users - think a taxi company buying a car, it is in use a lot more than a private car and if the taxi company has enough cars it's like everyone having their own. When you get to the biggest ISPs, they can't buy internet from anyone - instead they have what are called peering arrangements with each other that say if my customer wants data from your customer, it will go over this link. If the data flows are roughly symmetrical, this is often free. If not, there will be a charge (it's one of the reasons Netflix has caching near customer endpoints so data doesn't have to go over as much of the wider internet). An individual becomes an ISP by getting a connection big enough to support multiple customers that permits resale and getting some way to share that connection with the customers. The simplest way is to set up a WISP, a wireless ISP, which needs a tower with good visibility and some equipment on the tower and the customers home."
],
"score": [
6,
3
],
"text_urls": [
[],
[]
]
} | [
"url"
] | [
"url"
] |
|
7f74ml | Object oriented vs. Functional programming | Other | explainlikeimfive | {
"a_id": [
"dq9vvf2",
"dqa1078",
"dqa40k4"
],
"text": [
"Object-oriented programming creates entities and assigns properties to them. For example, you could create the entity dog, and assign it properties like name, age, owner, etc. You can then also manipulate these values. But what if you have two dogs? You can create a class (a template of sorts) called dog that has the properties name, owner, age and breed. You could then create entities sam.dog and barker.dog, which both have the same properties but different values, and thus you would have two distinctive objects that are of the same type but clearly independent objects. Essentially, the program code is based on the logic of having objects which contain data. This is very handy if you need to handle multiple entities. It also allows you to easily change data as you go and create new elements. Important especially in video game programming. Functional programming is a method of programming that is instead more focused on using functions (mathematical and otherwise) to carry out operations. It is more structured and most of the time easier for an untrained person to read, and also has a more sedate learning curve in my opinion. It is better suited for automating tasks and handling predictable data, especially if you don't need to handle multiple similar entities, such as the dogs mentioned above, but is less flexible and quickly becomes ridiculously convoluted when dealing with multiple entities. Well suited for straightforward tasks with stable data.",
"It's just two ways of looking at things a computer does. Objects are descriptions of data. They describe what the data is, name it and what can be done with it, which tries to give a clear meaning to the data. Functions are descriptions of processes. Here the focus is more on giving a clear meaning to the chaining of different processes, i.e. functions, and how they work together. Object orientation is good for complex data and simple functions, like getting all data points for your Facebook profile (Likes, Comments, Friends, etc). Functional is good for simple data and complex function chaining, like applying several complex mathematical functions to a long row of numbers. In the end both are just two ways at looking at the same thing (a CPU working on binary memory) and thus both are completely interchangeable.",
"In object-oriented languages, **objects** are responsible for maintaining an understanding of their own current state, and can communicate via passing messages to each other. So one object can tell another \"hey, BankAccount1234, withdraw $11\", and the recipient will check if the withdrawal can be made by looking at its own state (account balance, in this case) and some rules regarding when withdrawals are possible. If the withdrawal is permitted, the object will do so, and update its own state. In functional programming, **functions** are the main way of modeling the code's view of the world. A function could be \"given a current balance of X, determine whether a withdrawal of Y can be made\", and that would return true or false. That function would then be composed/combined with another, say \"given a list of accounts and an account number, return the balance for that account\". There is no concept of a \"bank account\", as such, because functions just deal with a very small and well-defined task defined completely in terms of data manipulation. A main difference is that a well-designed functional program contains many functions that are quite general in how they can be applied, so this *can* lead to great code re-use. In object-oriented programming, the main way to re-use code is to let one type of object extend upon another, via something called inheritance. So code that is valid for all Persons can be inherited by objects that model Employees and Customers. Further, all code valid for Employees is likely valid for Managers, Tellers, Janitors, and so on. To make an ELI5 summary: both approaches are ways of structuring your program and how it works with data. For some tasks, one may be more elegant and easy to understand than the other."
],
"score": [
20,
3,
3
],
"text_urls": [
[],
[],
[]
]
} | [
"url"
] | [
"url"
] |
|
7f76xa | How can a program teach itself to play a game like mario cart? | Technology | explainlikeimfive | {
"a_id": [
"dq9vmr2",
"dq9vrtu",
"dqa44me"
],
"text": [
"Software that learns how to play a game is usually based on a machine learning technique called 'reinforcement learning'. The problem with learning games is that you don't immediately know wheter a certain action or turn will lead to success (Imagine Go or Chess), so you lack labels for unique actions in the game. So you need a different approach - the reinforcement learning: A reinforcement learning program interacts with the game in time steps. At each time, the program receives an observation which typically includes the reward (like which rank, how many points it got) It then chooses an action from the set of available actions (randomly, or based on previous rounds or actions). At the next time, you see whether this improved, decreased or held the reward. When the programs performance is compared to that of an program that acts optimally or really good (e.g. a good human mario player), the difference in performance gives rise to the failure or 'regret'. In order to get better at the game, the program must 'reason' about the long term consequences of its actions (i.e., learn patterns that maximize the end result).",
"So if i run a program like that and go to bed. The program would have improved while i was sleeping?",
"The program needs to have some concept of whether it did good or bad. And then you tell it to, through whatever means necessary, maximize doing good. Basically, the same way you learned to play Mario Kart. You learned how to deal with sharp turns by playing it over and over until you had good strategies (\"good\" being measured in \"improving my overall speed\")."
],
"score": [
13,
4,
3
],
"text_urls": [
[],
[],
[]
]
} | [
"url"
] | [
"url"
] |
|
7f7hf8 | What makes any given bacteria inherently beneficial or harmful to humans? | Biology | explainlikeimfive | {
"a_id": [
"dq9x5z4",
"dq9x3t4"
],
"text": [
"A couple of factors play into this. 1. How well can it grow inside the body. This includes how well it adapts to the environment inside our body and also how well it can evade death from our immune system 2. Does it release toxins? This ones kind of a no brainer when it comes to harming the body. 3. How does our body respond to its presence? A lot of bacteria don’t actually damage the cells themselves, but certain components of them activate such a strong immune response that the body actually starts to hurt itself Those are the three biggest things that make for harmful bacteria. Beneficial bacteria are generally bacteria that can grow within our GI tract that don’t cause us much harm at all in there, but instead outcompete other bacteria that may cause disease",
"In most cases this has to do with what type of stuff the bacteria produces, but also how aggressively it out-competes other bacteria and whether or not it's capable of penetrating tissue on its own. The gut is a good example of some of these variables. For example, you've got E. coli in your gut all the time. Most E. coli is not bad for you. It helps break down certain food products so that you can absorb them. However, there are harmful strains of E. coli which are harmful because they produce a toxin. This toxin interferes with your gut lining and makes you really sick. Then you've got bugs like C. diff, also in the gut. We get exposed to this sometimes but we're just fine. However, when you're on really strong antibiotics, lots of the normal bacteria that helps out in the gut is killed. Dangerous C. diff strains aren't killed so easily, and it will populate all that new space really fast. This one also produces a toxin that'll make you sick when your gut is full of it. After that you've got stuff like salmonella, shigella, and campylobacter. These also produce toxins in most cases, but they tend to go one step further and actively invade the tissues lining your GI tract. Unlike normal gut bacteria, these guys are digging in and that doesn't feel very good."
],
"score": [
3,
3
],
"text_urls": [
[],
[]
]
} | [
"url"
] | [
"url"
] |
|
7f7ugh | How do we know when we’ve chewed something long enough? | Biology | explainlikeimfive | {
"a_id": [
"dqa0y0m"
],
"text": [
"When it's time to swallow, you have a thing at the back of your throat called the pharynx. Usually, air passes through it when breathing through either you nose or mouth. But when you're chewing, food starts you gather in it. Once it's reached a certain amount food, it triggers you to swallow, which is also why you might have to take multiple swallows per bite. (I just looked this all up on the internet, so if anyone knows any of this is wrong, feel free to correct me)"
],
"score": [
14
],
"text_urls": [
[]
]
} | [
"url"
] | [
"url"
] |
|
7f8bm0 | Why do we still have the common cold if we already had it once, shouldn't our bodies be prepared for it ? | Biology | explainlikeimfive | {
"a_id": [
"dqa2hj8",
"dqa2j1e",
"dqa2p9r"
],
"text": [
"Once we get a cold and get through it, we're immune to *only* that exact strain of the virus for life. The problem is that the cold virus mutates *really* fast, and the next cold you get is unfamiliar enough to the immune system that you get sick.",
"The common cold is not caused by one virus, but a lot of closely related, but distinct viruses. Viruses also mutate at a quick rate, so it's possible that after it's bounced around enough to get back to you it's changed enough for your body to longer recognize it as the same infection.",
"Your body has mechanisms to fix DNA if its mutated stopping it from being damaged. Viruses don't have this. If they get a mutation, they just go \"fuck it keep going.\" If the virus becomes dysfunctional, it dies. If it doesn't,it lives but your body's antibodies no longer recognise it because its not the same anymore so you don't have that innate immunity."
],
"score": [
17,
9,
5
],
"text_urls": [
[],
[],
[]
]
} | [
"url"
] | [
"url"
] |
|
7f8jsi | how did people prove ownership of land/porperty before 16 century ? | Other | explainlikeimfive | {
"a_id": [
"dqa4dr0"
],
"text": [
"In England, there was a lord who had a royal charter from the king to administer a certain area of the country, this lord could be a duke, earl, baron, or even a bishop. The areas controlled were small enough that they knew all the residents personally, and then they could rent out smaller parcels of their land to tenant farmers, collect the rents, and pass along a portion to the crown. So most things on the local level were done on a handshake basis. The lord of the manor would probably have to only keep track of 50 or less parcels of land, and could have a bookkeeper/overseer keep local records for him."
],
"score": [
6
],
"text_urls": [
[]
]
} | [
"url"
] | [
"url"
] |
|
7f8naf | Does activated charcoal passively collect fumes as any other surface or is there a 'pull' effect? | Chemistry | explainlikeimfive | {
"a_id": [
"dqaalxb",
"dqa75u3"
],
"text": [
"Passively is the answer to your question. It has a lot of surface area to catch things, but does not draw anything to it.",
"Activated charcoal has a huge surface area for the mass of the charcoal, but for this to be really effective the air has to be moved over the charcoal, though normal air movement (Brownian motion) helps."
],
"score": [
7,
3
],
"text_urls": [
[],
[]
]
} | [
"url"
] | [
"url"
] |
|
7f8pp8 | how can electrons just be ok on their own and fly around? | Where do these spare electrons come from? Do they come from atoms? If yes, how are the atoms able to just lose their electrons and it be ok? I mean like in the Maltese Cross experiment you're essentially "shooting electrons" but I just don't get where they come from. Thanks in advance :) | Chemistry | explainlikeimfive | {
"a_id": [
"dqa9plf",
"dqa9yo5",
"dqaam7q"
],
"text": [
"In certain substances, particularly metals, some of the electrons become community property, freely shared between atoms. These atoms are free to flow through the metal and are the reason metals tend to be good at conducting electricity. These electrons can be stripped away from the metal to perform the experiments you describe. The metal will have a slight positive charge and tend to grab electrons from the environment. The electrons will eventually join atoms to form negative ions, and those ions will be eager to give up their electrons. Over time, extra electrons will be lost and missing ones gain, and the overall system will reach equilibrium.",
"You can strip electrons off of atoms - these atoms become ions and are positively charged instead of neutral. In, for example, cathode ray tubes, in order to create a beam of electrons, you either heat up the cathode (which causes the electrons to essentially \"boil\" off the metal atoms) or you induce a very intense voltage difference between the cathode and the anode, which strips the electrons off the cathode.",
"Referring specifically to Maltese Cross experiment you're referencing, since the tube is not a perfect vacuum the electrons come from the atoms of air that remain in the tube. Although electrons tend to stick with atoms as they're attracted to the positive nucleus, with a bit of energy input they can be knocked free from atoms (think of using energy to pull apart ends of magnets that are stuck together). The force that strips electrons from atoms in this case is a high voltage. The rest of the atom is now a positively charged ion. There's nothing fundamentally wrong with this, it just means that now it will be attracted to negatively charged things (like as in electroscopes), and it can gain its electron back if there are free electrons floating around (in metals for example electrons jump very freely from atom to atom). It could even lose additional electrons, but usually those take more energy to remove than the first one. All this of course depends on what atoms you're working with. Some atoms will very easily give up their electrons, while others hold on very tightly. The study of this is basically the entire science of chemistry :)"
],
"score": [
15,
3,
3
],
"text_urls": [
[],
[],
[]
]
} | [
"url"
] | [
"url"
] |
7f95gf | How do laptops stay on when unplugged if it says the power source is from the adapter? Would't there be a moment of no power when switching to the battery? | Technology | explainlikeimfive | {
"a_id": [
"dqa8tqu"
],
"text": [
"1. (not necessarily in the case of your macBook, but) a lot of mobile devices _always_ run from the battery. Plugged in means the battery is constantly recharging. Which is not necessarily good for the battery, which is why a lot of laptop vendors will say don't leave it plugged in for an extended period. Run on battery, recharge. In fact I was just looking at Dell's support site for this. 2. the power supplies will have some kind of super capacitor in them which is capable of holding enough charge for just long enough to switch between AC and battery. And the switch really can happen near instantaneously, like milliseconds or faster."
],
"score": [
6
],
"text_urls": [
[]
]
} | [
"url"
] | [
"url"
] |
|
7f98ko | Why does 60 degrees outside feel completely different from 60 degrees inside? | Other | explainlikeimfive | {
"a_id": [
"dqa93lx"
],
"text": [
"Because temperature alone does not account for things like the sun heating up your skin, wind, humidity and various other factors. There are many different ways of measuring how hot or cold it feel heat index which takes into account humidity and global wet bulb which takes into account other factors like the sun's intensity"
],
"score": [
3
],
"text_urls": [
[]
]
} | [
"url"
] | [
"url"
] |
|
7f9aup | how esports commentators commentate right in front of the athletes? Does this not give away vital information especially in games like league and Starcraft? | Other | explainlikeimfive | {
"a_id": [
"dqa9g4c"
],
"text": [
"The eathletes are wearing headphones and they're usually in those booths, one per team. Exactly so they can't hear the reaction of the crowd (distracting, or a big \"ooooo!\" might be a tip-off your opponent just pulled something slick) or the announcers."
],
"score": [
7
],
"text_urls": [
[]
]
} | [
"url"
] | [
"url"
] |
|
7f9dte | Why are clouds distinctly different shapes but easily categorizable? | Other | explainlikeimfive | {
"a_id": [
"dqacl49"
],
"text": [
"The biggest different in cloud categories comes from whether the atmosphere is stable or not. A stable atmosphere essentially means the majority of air particles are falling/sinking. With stable atmospheric conditions, you get flat stratus clouds or fog/mist. With an unstable atmosphere, the air particles are rising. This creates cumulus clouds (puffy popcorn clouds). The more unstable the atmosphere is, the larger and more intense those cumulus clouds can get (Cumulonimbus clouds are just extreme cumulus). Cirrus is typically super cooled water or ice particles that are extremely small and suspended extremely high up (around 25,000ft). There is a lot more complexity to this, but hopefully this is a quick ELI5 version for you! Source: I is meteorologist."
],
"score": [
5
],
"text_urls": [
[]
]
} | [
"url"
] | [
"url"
] |
|
7f9eht | In the double slit experiment why did the wave function collapse upon observation? | Physics | explainlikeimfive | {
"a_id": [
"dqaajj8"
],
"text": [
"Because observation, on a subatomic level, means touching it. We don't have anyway to detect things other than just bouncing things off them and seeing what happens. For normal sized things we bounce photons off them and it doesn't really change what we are looking it. for subatomic particles bouncing something off it changes where it is. This is part of the basis for why we can know where something is, or how fast it is, but not both (heisenbergs uncertainty principle) on a subatomic level. Its because by \"observing\" it, we change it, we collapse the wave function."
],
"score": [
8
],
"text_urls": [
[]
]
} | [
"url"
] | [
"url"
] |
|
7f9n6j | Why does diarrhea happen? | Biology | explainlikeimfive | {
"a_id": [
"dqac9vy",
"dqad6xv"
],
"text": [
"So many reasons. Basically, it's just a symptom, a sign that your body is trying to get rid of something or that something isn't working as it should in your intestines. Usually you ate something that your body doesn't like, so it evacuates your intestines.",
"Basically it's like an overactive colon with decreased water absorption. The feces get moved along faster, and it retains more water than normal, resulting in an easier \"flow\" overall. It can be caused by sickness, lactose intolerance, food poisoning, and even stress. Really anything that upsets your system enough."
],
"score": [
3,
3
],
"text_urls": [
[],
[]
]
} | [
"url"
] | [
"url"
] |
|
7fakxe | How come spent nuclear fuel is constantly being cooled for about 2 decades? Why can't we just use the spent fuel to boil water to spin turbines? | Physics | explainlikeimfive | {
"a_id": [
"dqamsio",
"dqajzuq",
"dqarxpz",
"dqap3pi",
"dqaox6p",
"dqasjas",
"dqar6b6",
"dqatwbq",
"dqap8yi",
"dqarpmr",
"dqarfkb",
"dqb0dva",
"dqasgis",
"dqav5jt",
"dqarnzt",
"dqax0u4",
"dqax17t",
"dqapgnn",
"dqaytzb",
"dqb044b",
"dqaqjdo",
"dqbebbi"
],
"text": [
"Spent nuclear fuel just doesn't produce enough heat to make it useful for producing steam. The amount of power you'd get out of it that way simply would never pay for the cost of building and running the system. It can be recycled however. Spent fuel still contains a lot of useful radioisotopes and there are types of reactors designed to recycle the spent fuel back into usable nuclear fuel. The problem is, that on top of the normal political concerns with nuclear reactors, recycling can produce plutonium, which is used in nuclear weapons. Because it is very difficult to tell the difference between a fuel recycling plant and a weapon-making plant from outside, many countries have decided to not recycle to avoid political and diplomatic troubles.",
"It's just not cost effective to maintain a facility that can get power from the spent fuel. According to [this image]( URL_0 ) from wikipedia, after a mere 10 days power output is down to less than 0.5% of the original power output. Because of the nature of the graph, a year later it will probably still be about 0.1%. Clearly this is enough heat to warrant powered-passive cooling (like a computer fan, as opposed to powered cooling, such as a refrigerator). Any power station built to collect this power would produce 1000x less energy than a regular power station, which means the energy it produces would cost 1000x as much, assuming the operating cost of the facility is similar to a regular power station. It's cheaper to run a cooling station than to run a power station that doesn't produce any power. Edit: obligatory pun, it's not 10able",
"After three years in a pool we place the bundles in a cask and place them on a concrete pad to sit there until the country decides to develop a permanent storage facility or to reprocess the fuel. Reprocessing would make the most sense since over the 6 years that the fuel is in the core only, approximately, 3% of the fuel is expended. As for powering anything else the casks are all around 100 degrees so you are unlikely to get much energy from it. Source: I am a Senior Reactor Operator.",
"Could the spent fuel that still needs cooling not be used in a two step process? The used fuel could slightly warm the water heading into the Facility, it would stay cool and put even its small amount of energy to better use.",
"why can we use the spent material to power space probes? voyager is running on not a lot of power (reduced as it may be). If I understand decay right, wouldn't spent fuel last a long time as a space battery?",
"In the more modern candu reactors in the nicest plants in Canada, spent fuel from older style reactors can be used for years to still generate power. These reactors use a heavy water system that is pressurized to do boil the water etc. URL_0 Sadly most of our power generating is based on the same idea of boiling water to move turbines, so it's still highly inefficient.",
"Spent nuclear fuel maintains a significant portion of its available energy after being used in a traditional light water reactor - It is deemed \"spent\" after it gets saturated with fission byproducts. Once a spent fuel rod is removed, these byproducts and any remaining fuel isotopes need to be cooled since they still emit such a large amount of heat during their decay. Large cooling pools are used as interim storage for 5-10 years, then naturally ventilated dry storage casks are used for more permanent disposal. Alternatively, there is currently a push to repurpose these spent fuel rods as the primary fuel source of a lesser used reactor design, called a molten salt reactor. In this design, the fuel itself is dissolved in a heated salt solution (lithium, sodium, and other salts) that allows far more control over fission rates and is fundamentally safer to operate (fuel is already molten, so it can't melt). Also, this design is far more efficient, so it reduces the overall waste volume after operation. Hope this answers your question!",
"The left over heat is not powerful enough to fully boil the water. To make power in a steam turbine, the water must be boiled to the point where no water droplets remain. Any water droplets hit the turbine blades and break them. This is called 100 % quality steam. This is the same reason that power plants reject so much waste heat in cooling towers.",
"You can think of nuclear power like a carnival game where you throw darts at a wall of balloons. The balloons are fuel. Darts are neutrons. A dart hitting the balloon causes a fission event. Except there is no skill. All chance. So here's the gig. When all the balloons are on the wall, nuclear fission is easy mode. However now fuel starts to get spent. Now we've got lots of fissionable fuel but we might not get any power on a reliable basis because darts are hitting the wall and not creating heat. So what do we gotta do? Get a new wall with more balloons. So here's the gig. My analogy breaks down here. Sometimes a balloon gets hit and break into two balloons with a extra air (energy). Or the dart will stick inside the balloon. Natural part of fission. When these new ato... balloons pop. They release a thing called decay heat, producing heat with no neutron flux. That's why fuel constantly has to be cooled down. Remember these heavy atoms are in general much less stable than small ones, so their half lives are much shorter. It would be like your lawnmower kicking on and spinning the blade every once in while without you pulling the string but it happens on a continuous rate. Secondarily, these decay heat events release neutrons often. Water has two hydrogen atoms in it, so when those neutrons are released, the water will slow em down and stop the zoomies from hitting the people. ( The significance of hydrogen is that it's about the same size as a neutron so it slows it down better)",
"Just had this conversation with a nuclear specialist I know. He basically said that if buried under my driveway, I’d never have to shovel snow again, but I’d also glow slightly after a while. (Not really)",
"There has been research to create mini power plants about the size of a closet which use the heat of nuclear material encased in concrete to power 20,000 homes: [Mini Nuclear Plant Could Power 20,000 Homes]( URL_0 )",
"As the fuel breaks down it releases isotopes that begin to break down the crystal structure of the metals containing them. Under high pressure if the fuel is allowed to degrade too far it not only is less efficient at sustaining criticality it can break down the reactor. The contamination causes whats known as the winger effect as free neutrons knock the stable elements in the structural walls loose and leads to cracks. So its not just about power its also about the pressures that are operating and the limits of the materials we currently have engineered and this is also why we don't have thorium reactors. The liquid states of the fuel work against the support structure more than solid fuel configurations and its not economical to rebuild a whole reactor every 5 years",
"A nice description of a heat engine is in Wikipedia: _A heat engine acts by transferring energy from a warm region to a cool region of space and, in the process, converting some of that energy to mechanical work_ The thing is, the efficiency of any system which is converting heat energy to mechanical energy depends on the temperature and pressure gradients you have to hand. Huge generators run as turbines with both high pressure and high temperature and have a very large gradient across both down the system of rotating impellers. Even a low pressure reciprocal steam engine has high pressure and boiling steam. Nuclear spent fuel is emitting energy which heats water, yes. But, at a far lower intensity. There is a lot of water, which absorbs the neutrons and warms up (and also acts as a shield) but it doesn't boil and to get it hot enough you'd have to operate the spent fuel dump in a way which was probably close to the margins of safety. Basically, useful mechanical energy extraction works best with greater gradients of heat to cold and high to low pressure than is easily available from spent fuel rods. RTG works, but they're pretty specialised and unshielded or used in places like the Arctic.",
"Spent fuel has to remain in a spent fuel pool, being cooled by water for about 7 to 10 years. Depending on the type of fuel, burn time etc. After that it can be moved to long term dry cask storage. Keeping spent fuel is complicated, there are federal regulations you have to abide by, like multiple sources of cooling, power for those cooling systems, backup power etc.",
"Could be done, but to answer your question as to why it's is not done: the nuclear energy industry (at least in the US) is very slow to change anything - also, it takes a gargantuan amount of time and resources to get anything 'new' approved by the NRC. For example, the cover for the electrical outlet your computer is plugged into may cost you 3 dollars at the local hardware store. To have the same outlet cover installed in the office of the engineer at a typical nuclear plant may have a real coat of 300 dollars - and 100 pages of certification / documentation associated with it. This amount of detail and cost grown exponentially for actual technical equipment related to the power production process. For more info about waste heat power generation, beyond ELI5, it is technically possible - here is a link to a company that use low temperature waste heat to make power. URL_0 URL_0",
"Why don’t we heat water and homes with it?",
"Some reactor designs would do just that, but due to political pressure and the expense of building them they're never built. Edit: spelling",
"Spent fuel is still hot, sure, but it's nowhere near the energy output when it's still fresh. No point trying to milk all the last drops out of it.",
"Bill Gates did a very interesting TED talk called [Innovating to Zero]( URL_0 ) about some research they were (are?) doing on how to best utilize spent nuclear fuel.",
"ELI5 radioactive material: is it just always hot as hell burning holes in the ground? When it's mined is it really hot or does it need to be refined to be hot and full of energy?",
"The simple answer: it's hot but not hot enough to make steam to spin the turbines, but still to hot to not cool. The efficiency of heat engines depends on the **difference** in temperature or pressure. If the difference isn't big enough, the heat engine doesn't work well or at all.",
"Nuclear engineer here. Many people have mentioned actual temperature, but that isn't the full story. First, the spent fuel isn't cooled because it is too hot temperature-wise. It's too hot radiation-wise. If it was just the temperature too hot, we could bury the fuel in the dirt and forget about it. The radiation given off from spent fuel, however, is really deadly and the radioactive materials will stick around for many years. We actually want to bury the spent fuel in the dirt ( I'll get to more on this later) but we need to move it from the reactor to our giant hole in the ground. However, we would fry all the drivers on the road if we took the fuel straight from the reactor and put it on a truck. After about two decades the spent fuel becomes less deadly and the radiation given off can be much more easily contained for safe transportation. Why don't we just dig a giant hole under each reactor? Well, the hole needs to be thousands of feet deep, far away from drinking water, in a material that helps shield against radiation (like salt), and in an area that people are \"ok\" with (this last point involves politics that I won't get into). There are only so many places that meet these criteria, yet there are a lot of different reactors around the country. It's far easier and cheaper to let the spent fuel \"cool off\" for a bit then moving it to a different location, rather than digging a hole for each reactor. Edited for correctness."
],
"score": [
8102,
2316,
151,
134,
61,
39,
39,
21,
14,
13,
13,
13,
10,
5,
5,
3,
3,
3,
3,
3,
3,
3
],
"text_urls": [
[],
[
"https://upload.wikimedia.org/wikipedia/commons/2/22/Decay_heat_illustration.PNG"
],
[],
[],
[],
[
"https://en.m.wikipedia.org/wiki/CANDU_reactor"
],
[],
[],
[],
[],
[
"https://phys.org/news/2008-11-mini-nuclear-power-homes.html"
],
[],
[],
[],
[
"https://www.calnetix.com/access-energy-thermapower-orc-systems"
],
[],
[],
[],
[
"https://youtu.be/JaF-fq2Zn7I"
],
[],
[],
[]
]
} | [
"url"
] | [
"url"
] |
|
7fb96t | why is it hard to reproduce metallic colors (shine) accurately on display screen? | From Wikipedia (silver color): > there is no mechanism for showing metallic or fluorescent colors on a computer without resorting to rendering software which simulates the action of light on a shiny surface. is it because silver (metallic) is not a wavelength? | Technology | explainlikeimfive | {
"a_id": [
"dqansf2"
],
"text": [
"That's exactly the case! \"Shiny\" isn't really a color so much as how humans interpret the brightness as reflections. To see for yourself, find a picture of something shiny. Google image search, or screen cap something from a game. Now zoom in really close to the shine. It's probably some variant of grey. If you have a color copy tool, usually a dropper in Paint, take that color and fill in a giant block. The color of the \"shine\" should be pretty dull. In terms of absolute color, shine or matte aren't really anything unique. It's rather how the brain interprets the color relative to it's environment."
],
"score": [
3
],
"text_urls": [
[]
]
} | [
"url"
] | [
"url"
] |
7fbbl6 | How exactly could a boat be driven ashore by ice? | Edit: Say a boat traveling in the Arctic ocean | Physics | explainlikeimfive | {
"a_id": [
"dqapqcr"
],
"text": [
"> How exactly could a boat be driven ashore by ice? Ice covers a very large surface area of the ocean and wind can blow it around. If you have several square miles of ice being blown on by the wind that is a very large force and an enormous weight of ice which has been caused to move in a given direction. When a boat encounters that ice it is unlikely it will be able to do anything but be carried away by its force. Even when that ice encounters land the momentum and wind pressure on the ice behind it can push it up onto the shore. Any boat between the ice and shore will be carried along for the ride, potentially ending up a significant distance inland. [Here is an example of this sort of thing happening with a relatively thin sheet of ice.]( URL_0 )"
],
"score": [
6
],
"text_urls": [
[
"https://youtu.be/ISpsOERzWGo"
]
]
} | [
"url"
] | [
"url"
] |
7fbdju | Why aren't aspect ratios expressed in simplest form? | e.g. 21:9. Edit: of displays. | Technology | explainlikeimfive | {
"a_id": [
"dqapzpq",
"dqaoknw",
"dqausxm"
],
"text": [
"I might hazard a guess that its for easier comparison. 16:9 is a common resolution (i.e. widescreen), and 21:9 is marketed as \"Ultra-wide\", and comparing the terms 21:9 and 16:9 you immediate see \"oh, yeah, 21 is clearly bigger than 16\". If you reduced it to simplest terms, you'd be comparing ~~3:1~~ 7:3 and 16:9, and my immediate reaction to those is to actually think 16:9 is wider, despite actively knowing its not as I type this. Also, as said elsewhere, 21:9 sounds more impressive than ~~3:1~~ 7:3, so there's that too",
"For things like gears or cogs, it's how many teeth each wheel has, not a specific ratio. For other stuff it usually is. Do you have a specific example?",
"Because 21:9 makes it easier to compare to 16:9 so that consumers have an idea of what they are getting (an extra wide screen) without having to understand math or ratios that well. The actual ratio is 64:27 (2560x1080 = 64x120 x 27x120) or about 21.3:9 in order to follow 16:9 and 4:3 (4^2 : 3^2 = 16:9, 16^2 : 9^2 = 64:27)"
],
"score": [
22,
6,
5
],
"text_urls": [
[],
[],
[]
]
} | [
"url"
] | [
"url"
] |
7fbgpb | How come nuclear waste storage facilities need to possibly last longer than civilization? | Physics | explainlikeimfive | {
"a_id": [
"dqapffm"
],
"text": [
"> I understand that it stays radioactive for thousands of years but what warrants the construction of storage facilities that need to last longer that civilization on Earth? We don't really plan for civilization to end. If you know how long civilization is going to last then by all means let the rest of us know, because that is very much an open question. But nuclear waste storage facilities are planned around how long the waste will remain dangerous. Even if a future civilization forgets it is there and doesn't know what to do in order to contain it, it would be a dirty trick to leave such a deadly trap. It isn't going to kill all life on Earth but it can certainly taint a large area for a very long time."
],
"score": [
3
],
"text_urls": [
[]
]
} | [
"url"
] | [
"url"
] |
|
7fbtfg | Why does television have so much bandwidth compared to Internet? | Technology | explainlikeimfive | {
"a_id": [
"dqarwzc",
"dqasfrj"
],
"text": [
"The advantage television has here is that one signal is sent out by the transmitter, and everyone receives the same signal, and no return signal is needed, and different channels are using different frequencies. With an internet line, every end user is receiving an unique signal. (Also, 1080p is rarely used OTA, it's usually 1080i or 720p.)",
"When you watch a youtube video, YouTube opens up an individual connection specifically for you so that you can watch the specific video you want to watch. TV just blasts whatever they are broadcasting and anyone can pick it up. The benefit of the first option is that you can specifically choose what you want to watch."
],
"score": [
6,
3
],
"text_urls": [
[],
[]
]
} | [
"url"
] | [
"url"
] |
|
7fc211 | Why do we jerk forward when we sneeze? If we're expelling mass forward, shouldn't the jerk be in the opposite direction? | Biology | explainlikeimfive | {
"a_id": [
"dqatlac",
"dqawday"
],
"text": [
"You're also contracting your muscles specifically the ones near your diaphragm. Specifically, you clench your abs/core when you sneeze. The mass of air leaving your lungs is negligible.",
"Sneezing is like squeezing a near-empty ketchup bottle. You lurch forward to give the mass some initial forward momentum. This is followed by the actual expelling air, which drives the mass even more."
],
"score": [
15,
3
],
"text_urls": [
[],
[]
]
} | [
"url"
] | [
"url"
] |
|
7fcdmh | What makes a person allergic to something? | Is this determined from birth or is it developed over time? I myself am allergic to dust mites, pollen and animal fur | Biology | explainlikeimfive | {
"a_id": [
"dqb19h7",
"dqbfcvm"
],
"text": [
"IIRC its because of a single wbc misinterpreting something as a pathogen and urges other cells to fight it, and after that it's encrypted in our body to fight it",
"Because of the composition of the protein in the allergen. Antibodies interpret it as a threatening thing therefore releasing histamine (allergies)"
],
"score": [
5,
3
],
"text_urls": [
[],
[]
]
} | [
"url"
] | [
"url"
] |
7fcg3w | Why is it when a woman gets an epidural, there's a chance she'll always have some sort of pain that can't be treated for the rest of her life? | Biology | explainlikeimfive | {
"a_id": [
"dqb0b2w"
],
"text": [
"An epidural works by injecting medication directly into the space around the spinal chord. That means if anything goes wrong, it can directly damage the nerves of the spinal chord. That can lead to all kinds of complications."
],
"score": [
10
],
"text_urls": [
[]
]
} | [
"url"
] | [
"url"
] |
|
7fcha6 | What is the simplest explanation for how aenasthia works during operations? | Biology | explainlikeimfive | {
"a_id": [
"dqay0vz"
],
"text": [
"Local Anesthesia: Imagine each of your nerves is a person, and they form a crowd some distance away from you. If one of them yells \"Ouch!\" it'll get your attention, but you won't do anything because nobody else yelled, and they're all very close together. If a hundred of them yell \"Ouch!\" and a hundred more yell \"Impact!\" then you'll start responding because you're pretty sure there was a hit of some sort from that direction. When the anesthesia hits, *everyone* starts yelling, and it gets enormously confusing. Sure, some of them are yelling \"Ouch!\" and others are yelling \"Warm!\" and others are yelling \"Cold!\" and others are yelling \"Wet!\" and others are yelling \"That tickles!\" and you have **no clue** who to pay attention to. The brain stops trying to sort it out and it waits for the confusion to stop. The other nerves are trying to get the brain's attention and the small voices yelling \"Ouch! Knife!! Bleeding!! Burning!!\" are effectively drowned out in the shouting. That shouting is the numbness of anesthesia. Your brain can't make any sense of the signals coming from there, so it stops trying. General Anesthesia: You're unconscious, and typically a general anesthetic messes with your ability to form memories, so even though the nerves were yelling the whole time, your brain wasn't awake to understand and there was no memory made of that information. You wake up afterwards."
],
"score": [
6
],
"text_urls": [
[]
]
} | [
"url"
] | [
"url"
] |
|
7fcirv | Do flightless birds still have hollow bones? | And if they don't, which came first? The inability to fly or the inclusion of solid bones? | Biology | explainlikeimfive | {
"a_id": [
"dqaykx9",
"dqaxbwu"
],
"text": [
"It depends on the bird in question! Hollow bones are the ancestral characteristic in all modern birds, but more interestingly they go back *much* further than the evolution of avian flight, right through to [theropod dinosaurs]( URL_1 ) and even [sauropods]( URL_3 ) (which helps explain why *Brachiosaurus* and friends had such long necks; [source]( URL_2 )). Having evolved for reasons other than flight, there's no immediate reason to therefore suspect a loss of flight should necessary also result in a loss of this trait. Which perhaps is why most modern flightless birds still retain theirs - particularly all those recently flightless from isolation on islands; flightless cormorants, rails and the like. Some groups have lost this trait (or at least partially) for reasons other than flight too; say, to reduce buoyancy and aid diving. Penguins have solid bones and don't fly, but related grebes, loons and other aquatic birds have solid bones yet still fly ([source]( URL_0 )). This perhaps answers your question at least with respect to penguins; they evolved more solidified bones first, to aid with diving, and lost flight thereafter as a consequence of both this and reduction in wing size, rendering adventures in the sky too energetically costly ([source #1]( URL_6 ), [source #2]( URL_4 )). Ostriches and other ratites have a mix of the two. Most of their bones are hollow, but many found in their legs are are solidified, filled with a thick cortex to help support their great bulk ([source]( URL_5 ), indicating adaptation post-flightlessness. So yup, it depends! In any case, it seems more solidified bones come about for reasons largely independent of flightlessness *per se* though.",
"Some flightless birds do not have hollow bones, but it isn't likely their loss of flight and change in bone structure came about in sequence. Rather they probably gradually transitioned over a similar time period."
],
"score": [
10,
3
],
"text_urls": [
[
"http://onlinelibrary.wiley.com/doi/10.1111/j.1558-5646.2011.01494.x/abstract",
"https://en.wikipedia.org/wiki/Theropoda",
"https://peerj.com/articles/36/",
"https://en.wikipedia.org/wiki/Sauropoda",
"http://www.pnas.org/content/110/23/9380",
"http://journals.plos.org/plosone/article?id=10.1371/journal.pone.0149708",
"https://academic.oup.com/mbe/article/23/6/1144/1055321"
],
[]
]
} | [
"url"
] | [
"url"
] |
7fckc7 | What does it mean when economists speak of "stagnant wages relative to inflation"? | Economics | explainlikeimfive | {
"a_id": [
"dqaxovu",
"dqazgcq"
],
"text": [
"Say inflation is 2% a year and you made $100 this year. Then you make $102 next year, a 2% raise. Well because of inflation despite your raise, your income isn't any higher. If it was under 2% you would have more money, but less wealth. In addition say your company grew in value by 5%, you wouldn't be seeing any of that extra 3% growth on top of inflation. Over the last few decades wages have barely kept up with inflation (stagnated) while our economy has grown enormously. That new wealth that was created didn't trickle down to people, although we do have more goods and services and a higher quality of living. Just more debt and less wealth/savings.",
"Think of what you can buy with a dollar. Say, a bag of chips. So a dollar is worth a bag of chips. Let's say, you make 5 dollars or 5 bags of chips in an hour. All workers in your company - including you - get a raise to 6 dollars per hour. Price of chips rises to $1.20 - local grocery noticed that people are buying more chips lately - or gave their workers raise too and needed for extra income, so they adjusted the price. So even though you got a raise, your workhour is still worth only 5 bags of chips. Thus your wage raise didn't really change anything. Economists can't deny there's a wage raise, but they need to point out it's just an illusion in terms of buying power."
],
"score": [
8,
8
],
"text_urls": [
[],
[]
]
} | [
"url"
] | [
"url"
] |
|
7fckxr | ; How is our voice determined for ourselves and is there a way to permanently change it? | Biology | explainlikeimfive | {
"a_id": [
"dqb2zdo"
],
"text": [
"genetics play a role here. how a child's voice develops owes something to mimicking of their parents. people from the same family will often sound alike because their anatomy is linked to their ancestral DNA -- just like every other physical trait. you can change the hoarseness of your voice by smoking, exhausting it (such as making high pitched noises for long periods of time), or damaging it (using any material -- basically stretching the vocal cords, that is, if you can reach them without gagging). a good example of a voice change would be lindsay lohan. also, you can adjust your vocal pitch (as well as timbre and inflection, thanks Hoihe!) by doing specific exercises. many people who consider changing their voices when they transition their gender do these."
],
"score": [
8
],
"text_urls": [
[]
]
} | [
"url"
] | [
"url"
] |
|
7fcl30 | Most (but not all) male mammals are larger than females, but most (but not all) female insects, arachnids and fish are larger than males. Why does female-male sexual dimorphism vary by biological class? | Biology | explainlikeimfive | {
"a_id": [
"dqayucr"
],
"text": [
"Arthropods and fish lay masses of eggs which are large in comparison to the size of their bodies; that is their reproductive strategy. Mammals in comparison do not lay eggs but just produce tiny ova which, if fertilized, will then gradually grow into a baby. The biological requirements for these different reproductive strategies necessitate different body sizes. In mammals, the primary evolutionary pressure has been for larger, stronger males who can successfully compete with other males for access to females. In fish, the primary evolutionary pressure has been for large females who can produce large quantities of eggs."
],
"score": [
7
],
"text_urls": [
[]
]
} | [
"url"
] | [
"url"
] |
|
7fcpqj | Why does increasing the time before stopping reduce the force of an impact? | Physics | explainlikeimfive | {
"a_id": [
"dqaztf7",
"dqb6vj7"
],
"text": [
"> In something like a car crash, why does increasing the amount of time it takes a person to come to a stop reduce the force they experience? Because force is defined as mass multiplied by acceleration, and acceleration is defined as distance divided by time squared. Or, to put that in equation form: f = m*a a = d/t^2 So combining the two, you get: f = (m * d) / t^2 Since time is in the denominator, making it larger makes the force smaller.",
"You can look at this physics problem from different angles. One of the easiest (I think) is to look at the Energy. Before the crash, the car has a certain amount of kinetic energy due to its speed, and after the crash that will be gone, so during the crash that energy has to be dissipated - it has to go somewhere. The rate at which this happens (power) is the variable here. There's a simple equation for this: energy = force x distance. It explains gears and pulleys, and why it's easier to walk up a slope than to climb straight up the same height: by spreading the work over a longer distance, you require less force for the same result (change in potential energy). So, if you can increase the car's stopping *distance*, less force is required to stop it (dissipate the energy). That also translates to more time (because distance = speed * time). Less force on the car = less force on the passengers."
],
"score": [
20,
3
],
"text_urls": [
[],
[]
]
} | [
"url"
] | [
"url"
] |
|
7fcqyi | why do colors fade over time? Where does the pigment go? | Chemistry | explainlikeimfive | {
"a_id": [
"dqaz6ap"
],
"text": [
"In most cases it is exposure to sunlight which causes colors to fade. Sunlight includes ultraviolet (UV) light which carries more energy than the lower frequencies. What happens to pigments is that they break up into smaller molecules which usually do not have the same color. So the pigments have not actually gone anywhere, but they have been damaged by UV."
],
"score": [
10
],
"text_urls": [
[]
]
} | [
"url"
] | [
"url"
] |
|
7fcqzu | Why do warmer alcoholic beverages get absorbed into the system quicker? | Lately when my drinking buddy and I drink we have had the beer as it's been sitting out. We feel immensely more buzzed, or intoxicated when the beer is warm. We've reasoned it out to our bodies having a tougher time absorbing when we drink something ice cold. What's happening? Also, we drink the warm beer slower, because it's gross. (Had to repost cause I forgot the tag, and knew mods would delete) | Biology | explainlikeimfive | {
"a_id": [
"dqb0t4x",
"dqb008s",
"dqbm1c8"
],
"text": [
"I can't find any literature linking the temperature of a drink to it's absorption rate. And as far as I'm aware, the temperature of alcohol doesn't affect the rate of absorption. Things like how full your stomache is, weight, gender, do. And because how \"buzzed\" you feel is a \"feeling\" vs. an objective measure like blood alcohol content, the placebo effect is significant. If you believe the temperature of a drink affects absorption, it'll definitely feel like it. If you have a home breathalyzer you can experimentally check. One day get drunk on cold beer and measure your BAC periodically. The next day get drunk on warm beer. Be sure to eat the same amount of food before hand and consume at the same rate. Please get drunk for us in the name of science and report back your results. Edit: abortion doesn't have anything to do with absorption",
"Because your body absorbs any liquid only once it reaches body temperature, and warm beer has less to go to get to body temperature.",
"It seems like I've read before that warmer temperature promotes gastric motility? Like Warmer food/liquid is transferred from stomach into intestines quicker than colder temp stuff. Is alcohol absorbed in the stomach or more so in the intestines? Would this have any bearing on answering OPs question?"
],
"score": [
5,
4,
3
],
"text_urls": [
[],
[],
[]
]
} | [
"url"
] | [
"url"
] |
7fd55t | What contributes to a room or space becoming "stuffy" and how can our bodies tell? | Chemistry | explainlikeimfive | {
"a_id": [
"dqb229y"
],
"text": [
"Primarily it is a lack of air movement. Your bodies tell by the pocket of warm air around your body warmed by your body heat stops being disrupted thus hindering your body cooling properly. You tell by the odors around you (and from you) not moving about and becoming stale. And there are many other smaller cues."
],
"score": [
6
],
"text_urls": [
[]
]
} | [
"url"
] | [
"url"
] |
|
7fd6ci | How do TV shows that post videos on Youtube earn enough revenue to continue existing? | I'm talking about shows like Last Week Tonight with John Oliver, which basically post the bulk of their episodes on YouTube | Technology | explainlikeimfive | {
"a_id": [
"dqb236b",
"dqb26ly",
"dqb3pdi"
],
"text": [
"Ads. Plus if you like it enough you might actually tune in. If not & you remain on Youtube; ads. Otherwise you wouldn't have begun & they wouldn't have made cash on you in the 1st place.",
"John Oliver is made by HBO. They get their money from investors and from those that pay to watch HBO. The show also gets ad revenue from Youtube and because it is the channel of an established TV network will rarely be demonetized.",
"1) Ads! these work as you think, someone watches ad and you get paid. People as big as HBO may be able to cut special revenue sharing deals with Google and Facebook. 2) Free advertisment. You like a clip and give your friend the youtube, he watches it and may like it and tune in on TV. Bam new viewer. Also if it just happens to come up on the next auto playlist. 3) More free advertisement. You can show up on someone's facebook and twitter feed. 4) Figure out which clips people like. TV kind of sucks at user metrics. Computers are way better, so good it is scary sometimes. They can then adjust future shows."
],
"score": [
12,
5,
4
],
"text_urls": [
[],
[],
[]
]
} | [
"url"
] | [
"url"
] |
7fda0m | Is eating your daily caloric intake in one meal the same on your body as the normal 3 meals to do the same? | Biology | explainlikeimfive | {
"a_id": [
"dqb305e",
"dqbclj6"
],
"text": [
"Some fitness guys do intermittent fasting, which is highly customisable. Most intense which i have seen is, not eating for 23 hours, then last 1 hour, you fill your body with required daily calories intake, but that goes with good metabolism, good routine and practice.",
"It definitely is not the same. There is a limit to how many nutrients your GI tract can absorb in a pass. So if you eat a very large meal lets say about 15000 kJ in one sitting, you might not absorb nutrients as effectively as when you space this out over 3-4 meals."
],
"score": [
5,
5
],
"text_urls": [
[],
[]
]
} | [
"url"
] | [
"url"
] |
|
7fdb5i | How do computers generate colours without reflection? | Physics | explainlikeimfive | {
"a_id": [
"dqb4cvu"
],
"text": [
"> How do computers generate colours without reflection? The standard computer screen these days is the LCD, or Liquid Crystal Diode. These screens use tiny crystals suspended in a somewhat fluid matrix which allows the crystals to be oriented using an electric field. In one orientation they allow light to pass through them while in another orientation they block light. You can observe this behavior with the classic digital watch or calculator on a sort of greyish green background. Those are simply liquid crystal cells which are made opaque to display numbers over a matte background. A modern LCD screen uses a white backlight which shines through a very fine grid of individual liquid crystal cells. Three cells are grouped together into a \"pixel\" with each cell being tinted the colors red, green, and blue. By varying how much the liquid crystals blocks light from each of the colored cells the combined color of the pixel unit can be adjusted. Combining many of the pixel units together allows an image to be formed. An older display technology was the CRT or cathode ray tubes. Instead of a white back light the red, green, and blue components of a pixel were activated by shining an electron beam into them which would cause them to fluoresce. Scanning this beam back and forth across the screen would build the image from the same kind of pixel groups. A newer display technology is OLED or organic light emitting diodes. These displays have the red, green, and blue components of the pixel groups composed of individually activated LEDs, a semiconductor light source using electroluminescence. In principle though they form an image in a similar way as the other displays."
],
"score": [
4
],
"text_urls": [
[]
]
} | [
"url"
] | [
"url"
] |
|
7fdgrm | Why does audio rapidly repeat itself when a computer crashes? | Technology | explainlikeimfive | {
"a_id": [
"dqb54m0"
],
"text": [
"At a high level, sound cards playback sound by reading digital data from a buffer and converting it into an analog signal to transmit to the speaker. When a normal stream of audio is being played back, its data is written into the buffer as a stream so there's no hops or skips - as the digital audio converter scans back and forth over the buffer, the buffer data is overwritten as its being played. If the audio controller crashes but the hardware is still going strong, it begins to simply replay what happened to be in the buffer at the point of the crash, causing the effect you describe. The audio will fully stop if the OS can catch the program going unresponsive and eject it from memory, which frees the audio controller."
],
"score": [
29
],
"text_urls": [
[]
]
} | [
"url"
] | [
"url"
] |
|
7fdk7y | why does beer make us pee so often. | Biology | explainlikeimfive | {
"a_id": [
"dqb5ivk"
],
"text": [
"Alcohol reduces the production of a hormone called vasopressin which tells the kidneys to reabsorb water as opposed to allowing it to pass into the bladder. Alcohol strongly increases the production of urine to the point that for every unit of alcohol consumed urine production will be increased ten times that amount. Beer also contains a large amount of water anyway so you would already expect increased urination, but alcohol tells your kidneys to dump even more water than usual."
],
"score": [
3
],
"text_urls": [
[]
]
} | [
"url"
] | [
"url"
] |
|
7fdm4s | why does every website including Reddit want me to use an app instead of their damn website these days? | Technology | explainlikeimfive | {
"a_id": [
"dqb53k1",
"dqb57gq"
],
"text": [
"Hmm those apps sit in the background and silently collect user data. All those permissions you give them? Full contact, internet, storage, location access? They dont need all of that to work. They may need some, but they're collecting data silently. And you wonder why there's so much battery drain. After all you've signed your privacy away when you agreed to the permission access.",
"Apps have a lot more permissions and device access than mobile web. For example, your web browser typically will not have camera access, which is why places that want to scan br or QR codes will need to have an app. Apps also can usually access more memory than mobile browser tabs, useful for high memory consumption sites. Spying is a big part of it though"
],
"score": [
3,
3
],
"text_urls": [
[],
[]
]
} | [
"url"
] | [
"url"
] |
|
7fdmdk | how do tv commercials work? | Is there a guy in a room somewhere picking them? Why do some only last a split second? Why are there sometimes 2 or three in the same break? How is the length normally set? Who picks them ? Etc | Technology | explainlikeimfive | {
"a_id": [
"dqb5icc"
],
"text": [
"TV commercials are bought and placed into \"slots\" during regular programming. For instance, Doritos or Pepsi or whoever can choose to buy a slot that's open in the middle of a broadcast of CSI or whatever show. Typically companies do a lot of demographic research to see what their target consumer watches (sugary cereals usually slot their ads into kids TV shows, that's an easy example). Likewise, length varies, but ads can be a few seconds up to 15 or 30, typically. The \"split second\" ads that only blink on your screen are probably just glitches, bits and pieces that didn't quite get slotted in correctly OR it's interference from another channel. EDIT: regular network TV shows are generally a half hour or a full hour - a \"half hour\" show is typically 21-23 minutes while a \"full hour\" is roughly 48 minutes. This is standardized so networks can consistently produce their shows. Whatever time is left, that 7 or 9 or 12 minutes, is broken into 3 or 4 ad breaks, and those breaks can be split into segments of 15, 30, however many seconds and then sold to advertisers."
],
"score": [
4
],
"text_urls": [
[]
]
} | [
"url"
] | [
"url"
] |
7fdscl | how does being vegetarian change your body? What happens to your body if you started to eat meat after 20 years of being veggie? | Biology | explainlikeimfive | {
"a_id": [
"dqb6g98",
"dqbd1xn",
"dqbckfr"
],
"text": [
"If someone stops eating meat for a significant amount of time, it’s possible that the amount of enzymes dedicated to animal-protein digestion might reduce a little to compensate for the increase of other food groups in the system. This isn't permanent, it'll just take the person's body more time to digest and may cause an upset stomach. They will eventually adjust to an omnivore diet.",
"As far as it goes, your intestinal flora is geared to adapt very quickly to a meat-based diet (we are talking about weeks). Bacteroides are short-lived, but very quick to reproduce, whereas the vegetarian-orientated flora (ruminococcus) are longer lived and slower to reproduce. Approximately 70% of your gut flora changes to suit the meat-based diet within 4-7 days of eating meat. To go from meat-based to plant-based takes much longer - around 4-6 months. Evolutionarily speaking, this makes sense. Early humans lived primarily on plants but if they could get their hands on meat, would likely have eaten nothing but meat for a few days (to stop it from being wasted through rotting). This would have been a time prior to hunting and preserving meat. Having the ability to quickly switch to meat and then go back to nothing but plants would have been hugely advantageous to humans.",
"I was vegetarian for 12 years when I went back to meat. I had some intestinal distress with red meats for a while but it only lasted a couple months."
],
"score": [
29,
11,
5
],
"text_urls": [
[],
[],
[]
]
} | [
"url"
] | [
"url"
] |
|
7fdu5q | What is the life cycle of ringworm? | Biology | explainlikeimfive | {
"a_id": [
"dqb6le0"
],
"text": [
"Ringworm is a fungus, so its lifecycle is similar to that of other fungal skin infections: * human encounters spore on infected linen, clothing, or by bodily contact * spore begins to germinate and mature fungal infection occurs * fungus generates new spores which distribute themselves as part of the usual constant skin detritus (dead skin cells etc)"
],
"score": [
3
],
"text_urls": [
[]
]
} | [
"url"
] | [
"url"
] |
|
7fdvup | - Why does extended exposure to water dry your hands rather than moisturize it? | Biology | explainlikeimfive | {
"a_id": [
"dqbfct3"
],
"text": [
"Osmosis is the diffusion of water. When you overflow your hands or any body parts or almost any tissue/organism with water, the net flow of water will be wherever there is a higher concentration of solute. When you put water on your hands, it flows in because there is more solute like salt in your blood and inside than out. This is why you soak lettuce and vegetables in water before serving to make them crisp, and in the same fashion, if you soak vegetables in a bucket of salt water, they will wilt."
],
"score": [
3
],
"text_urls": [
[]
]
} | [
"url"
] | [
"url"
] |
|
7fe9s5 | How is it that we can't smell our own breath, but are able to smell the unique "smell" that comes from other peoples' breath? | Biology | explainlikeimfive | {
"a_id": [
"dqb8up8"
],
"text": [
"You do smell your own breath, and see your own nose, and hear the blood in your ears etc. Your brain adapts to ignore constant stimuli."
],
"score": [
17
],
"text_urls": [
[]
]
} | [
"url"
] | [
"url"
] |
|
7fepmz | Why is chicken pox relatively harmless in children but potentially fatal in adults? | Biology | explainlikeimfive | {
"a_id": [
"dqbcf48",
"dqbcgl1",
"dqbch5k",
"dqbw0ll"
],
"text": [
"They're not exactly sure why, but adults are much more likely to get dangerous side effects from chicken pox than children. They are more likely to end up in the hospital with complications like pneumonia and meningitis which is what can kill them. [ URL_0 ]( URL_1 ) has one of the theories which is that \"Kids' immune systems are dominated by phagocytes, which are big cells that \"eat\" any foreign material, while adult immune systems employ more antibodies, which attack microbial invaders like X-Wings attack TIE Fighters. It might be that the hungry, hungry hippo style of immune system is just more effective against certain viruses.\"",
"We don't actually know why, but the child immune system and the adult immune system react differently to the varicella-zoster virus and that means that the adult infection can come with rather fatal complications as a result of infection. The reasoning can be due to how our antibodies react to infections (adults have been infected more so their antibodies have greater memory of more viruses) and perhaps the composition of different white blood cells in our body (they have very complex interactions). But it can cause greater levels of fluid trapped in the lungs, known as pneumonia which can be incredibly uncomfortable and feel like you can't breathe. It can also cause infection and inflammation within the brain (encephalitis) which is very lethal. You can also die from your immune response having a huge body-wide reaction to the virus (sepsis). Because of how infectious it is, you can catch it from your child, or any child, as well as contact with people who have re-emerged virus which is known as Shingles. If you've never been vaccinated or infected, its strongly suggested that you do get vaccinated ASAP.",
"The science on this isn't really well understood. It is speculated that this occurs due to the difference between the immune systems of adults and children. Adults are more likely to get complications (e.g. pneumonia - a lung infection) from chickenpox, whereas children are not.",
"Since no one knows why, it might just have to do with how the younger you are, the better your immune system is. For instance, if a baby breaks a bone, that shit heals up in a much smaller window than it would take for an adult to recover."
],
"score": [
1409,
52,
7,
6
],
"text_urls": [
[
"Curiosity.com",
"https://curiosity.com/topics/why-are-the-chickenpox-so-much-worse-for-adults-curiosity/"
],
[],
[],
[]
]
} | [
"url"
] | [
"url"
] |
|
7feq4d | Why are rhyming and cadence so pleasant? | Biology | explainlikeimfive | {
"a_id": [
"dqbbbx2"
],
"text": [
"The human brain automatically tried to find patterns in everything, to make it easier to understand the world. Rhyming and cadence already form patterns, so you use less energy to process it. That makes it so pleasant."
],
"score": [
11
],
"text_urls": [
[]
]
} | [
"url"
] | [
"url"
] |
|
7ff1mf | How do international credit ratings work? Italy has never defaulted on its sovereign debt, Germany has defaulted over 5 times. Why does Germany have a better rating than Italy? | Economics | explainlikeimfive | {
"a_id": [
"dqbd48i"
],
"text": [
"well, they are issued by companies that all have their own unique blend of reasons to issue them. but considering at least 4 of those 5 times \"Germany\" defaulted it was a different country, it is pretty obvious they will pay more attention to the current economic situation than how the country (or whatever country was there in 1500) handled things several centuries ago as stated in the link you provide, that graph is incredibly missleading and just for fun, not for serious contemplation"
],
"score": [
7
],
"text_urls": [
[]
]
} | [
"url"
] | [
"url"
] |
|
7ffj4s | What is project treble and what does it mean for Android? | Technology | explainlikeimfive | {
"a_id": [
"dqbhvww"
],
"text": [
"Treble separates the vendor specific part of the OS from the Android specific part of the OS. Because there are two separate parts now, the vendor can focus on \"their side\" of the house when working on getting their devices for the major android updates. While before, a manufacturer/vendor (HTC/Samsung vs Verizon/Sprint) would have to rework the entire android OS in many different areas to make it fit their device. Now they'll only have to worry about the driver side, instead of customizing android as a whole. What it means is when a large upgrade comes out (like Oreo), the vendors will be able to get their phones upgraded to the best and the brightest OS faster, only having to do about 1/3rd of the work from before."
],
"score": [
3
],
"text_urls": [
[]
]
} | [
"url"
] | [
"url"
] |
|
7ffkio | Why is the sky never green, besides the aurora borealis-northern lights? | Chemistry | explainlikeimfive | {
"a_id": [
"dqbj2r9",
"dqbj3lp",
"dqbjbnt"
],
"text": [
"It can look green, especially prior to a tornado. I believe sometimes in hurricanes it can also look green.",
"The sky will sometimes turn to a very strange and eerie green in the calm before a tornado. I believe it has something to do with the sun reflecting off at a different angle due to the ice crystals in the clouds.",
"This is actually more of a physics question than chemistry. When the light from the sun reaches the sky, it begins to bounce off of the molecules that make up the air (nitrogen, oxygen, etc). It's easiest for the molecules to scatter the blue light around because it has the shortest wavelength. (Red has the longest wavelength, and that's why our sky isn't red.) So when we look up, we're picking up light from the sun, and a disproportionately large amount of that is blue because more of it has been scattered around and has a greater chance of getting in our eyes."
],
"score": [
13,
7,
7
],
"text_urls": [
[],
[],
[]
]
} | [
"url"
] | [
"url"
] |
|
7fg18d | Why do certain websites load several times in your browser history, so that when you click the back button it doesn't do anything? | Technology | explainlikeimfive | {
"a_id": [
"dqbl3nu"
],
"text": [
"Because they are assholes, and don't want you to leave the website by hitting the back button. BTW you can right click the back button, and choose a location from the history that pops up."
],
"score": [
3
],
"text_urls": [
[]
]
} | [
"url"
] | [
"url"
] |
|
7fg9ur | I’ve stood every single day of my life, so how are my legs and back still sore after a day of work when they should be used to the strain? | Biology | explainlikeimfive | {
"a_id": [
"dqblfi4",
"dqbm1hl"
],
"text": [
"Your body doesn't handle standing all day well . It didn't evolve that way. Standing and moving takes a lot of muscle effort for us to maintain and is very hard on our joints.",
"You can only get used to it to a certain extent and then it starts to strain. It'll take evolution over generations doing the same thing to get that \"used to strain\" feeling."
],
"score": [
9,
3
],
"text_urls": [
[],
[]
]
} | [
"url"
] | [
"url"
] |
|
7fgkbr | Without animal testing, how do cosmetics and skin care companies determine that their products are safe? | I'm a biologist by training and work on mouse models for drug testing. With medicine, every single approved drug was first extensively tested in animal models. My question is, without animal testing, how do cosmetic and skin care companies know that their products won't have adverse effects on humans? Do they test solely on humans? That sounds very dangerous... | Chemistry | explainlikeimfive | {
"a_id": [
"dqbuy3n",
"dqbx509",
"dqbojtt",
"dqc0j99",
"dqbnx99"
],
"text": [
"They test them on unsuspecting sub-Saharan African people who have very limited understanding of informed consent. Sadly, I'm not kidding.",
"Some companies say \"This product not tested on animals\" but in some cases the ingredients are tested individually on animals. Sometimes products are tested on humans, typically poor folks in other countries, or the developers test on themselves. Testing cosmetics is somewhat safer than testing a drug that has to be taken internally, but of course we also need to realize that some things which are toxic to other animals are safe for humans, and visa versa.",
"There are several viable alternatives to animal testing. - ***In vitro* experimentation:** *In vitro* experiments are performed on live cell or tissue samples that mimic human reaction to different drugs or cosmetics. Some *in vitro* models are already replacing rabbits, guinea pigs, and mice for research on corrosive substances and allergic reactions, due to their actions more accurately replicating those of humans. - **Microdosing:** Microdosing involves testing small, less-than-harmful samples on a live human volunteer. This type of testing is safe and is typically more effective for research about humans than animal testing. - ***In silico* testing:** *In silico* testing involves testing on computer-generated models. These models are often based around predictive programs and are being promoted as replacements for animal testing on a global scale. - **Human patient simulators:** Human-patient simulators are lifelike dummies that can perform actions such as talking, breathing, and bleeding. They have been shown to be more effective in learning environments than experiments on animals such as rabbits.",
"They can make products out of GRAS (generally recognized as safe) ingredients and ingredients that have already been tested on animals (in the past, not necessarily by that company or for that purpose). Some products say that the \"Finished Product\" has not been tested on animals, without having to say that some of the ingredients were in the past. The biggest difference is that new medicines might be completely new chemicals, whereas new cosmetics are often just mixtures of existing ingredients.",
"I used to know some people who got paid to be human guinea pigs for new drugs, so I'm guessing that there's going to be similar things for skin care stuff. There used to be similar testing for fertilizers, pesticides and such. Have to know what the effects will be."
],
"score": [
35,
15,
13,
10,
6
],
"text_urls": [
[],
[],
[],
[],
[]
]
} | [
"url"
] | [
"url"
] |
7fgnv4 | Why does smoking the same amount of pot from the same batch affect you so differently from day to day? I.e. sometimes it’ll barely affect you and sometimes it’ll knock you on your butt. | Biology | explainlikeimfive | {
"a_id": [
"dqbpgvi"
],
"text": [
"TL;DR: the less stuff your body has going on, the more you will feel it. & nbsp; Okay so, this is all anecdotal and based off of my experience and base knowledge of the body. You ever notice you feel way more high when you smoke on an empty stomach? Basically, your bloodstream has a ton of stuff it carries around your body. When you have very little being transferred around and you smoke, it'll flood your bloodstream and it feels more potent. But when your bloodstream is carrying things around, the THC is diffused and therefore you feel it less. Hope that makes sense. As a rule, I never smoke on an empty stomach, it leads to binge eating and me getting far higher than I planned to."
],
"score": [
7
],
"text_urls": [
[]
]
} | [
"url"
] | [
"url"
] |
|
7fgomy | Why do pipes in the shower sing when certain temperatures of water goes through them? | Physics | explainlikeimfive | {
"a_id": [
"dqbs4x9",
"dqbxq24",
"dqc6ajg",
"dqcbf8x",
"dqc4k5x",
"dqcs702"
],
"text": [
"It has to do with the vibrations caused by the water flowing through the valve. As you turn it to hot, the cold valve starts to close off more until it's barely passing water through and causes it to whistle, just like whistling with your lips. You have to restrict the airflow by closing off your lips to create the whistle sound and as you change the speed of the air and size of opening in your lips, the sound changes with it. This is what's happening with the water and the valves in your shower. The temperature doesn't matter to the sound, it's just that when you turn it up hotter you're closing off the cold valve more and more.",
"If it's a really loud noise it is likely caused by the valve you have, I saw this covered on an episode of this old house long ago. Your sink or bathtub or toilet have shut off valves in the line before the water reaches the valve at the sink or bathtub, this is so you can replace the main valve without having to shut off the water main. The older style valves have a rubber seat that is loose when it is in the open position, The rubber seat picks up a vibration as the water flows by. When it hits the right frequency it becomes extremely loud. To fix this they replaced the old valve with a new ball valve, it doesn't have any loose components that can start to vibrate.",
"Wait .. is this common? I don't think I've ever experienced this or at least not properly noticed it.",
"This can be caused by a few things. By putting your ear to the various areas of the shower you can tell pretty easy which one it is. 1) if the noise is coming from the shower head area, simply buy some lime-a-way and put it in a sand which bag and dip the head in it or hold it over the head. 2) if the noise is coming from the area of the handle where you turn it from cold to hot, you will need to replace your shower cartridge. You tube it it pretty simple to do. 3) if it’s coming from the downspout area where you lift the little handle to send it to the shower head, I would just replace that. It’s about 15-$20 at Home Depot or Lowe’s. You can buy a universal one and it’s pretty easy to install as well. I know this because I literally just fixed to showers in my sisters house. One was fixed by #2 and one was fixed don’t #3. Pretty straightforward and I hope this helps!!!",
"Have you received any tips on how to fix this issue? My shower sings constantly",
"Plumbing systems can make some horrific noises. As a plumber I am called to many noisy plumbing jobs. There can be grinding sounds, groaning, sudden bangs, whistles and whines. Most of the time the cause is high water velocity and faulty valves or taps. The loose jumpers (the moving part with the washer attached in stopvalves) in stopcocks can make a lot of vibration or humming sounds if the water velocity is too high. Unclipped pipes can jump and bang when taps are shut quickly. Float valves are the most common cause of vibration noise in homes. Just as they are lifted to fully close, a splash of water disturbs the surface inside the tank and sets the float valve bouncing, opening and closing the valve in quick succession. I like fixing these problems and have even managed to prove to people they don't have a poltergeist, just bad plumbing. In the case of your shower the top comment has the right answer although if you have hard water, scale buildup in your shower mixer could be causing restriction of flow and that can make a whistling sound too. Or the valve may simply be faulty and a replacement cartridge will fix it."
],
"score": [
3019,
92,
58,
15,
14,
3
],
"text_urls": [
[],
[],
[],
[],
[],
[]
]
} | [
"url"
] | [
"url"
] |
|
7fh92g | virtual particles please. | I understand the basic concept behind them but would like to know more. | Physics | explainlikeimfive | {
"a_id": [
"dqbwmcn"
],
"text": [
"Virtual particles are particles that *cannot* be measured but *must* exist. Take, for example, two electrons interacting with each other. Because they have the same charge, they will repel each other. How do they \"know\" they have the same charge? How do they \"know\" that there's another electron nearby repelling them? They share a photon. The photon carries the electromagnetic force between the two electrons, transferring momentum between them and sharing the information to each of them that they exist. That photon has to be there. That photon is how the electrons communicate - it's how any charged particles communicate. That photon is also undetectable. You detect photons by having them interact with charged particles. But the photon is already interacting with two charged particles. It can't make a pitstop through your detector. If it gets detected, it's absorbed, and the information it was carrying between the two electrons is gone. It's not like you \"aren't allowed\" to detect that photon, you just *can't*. As far as anything other than the two electrons is concerned, the photon doesn't exist. And in a shaky kind of way, it really doesn't exist. Does something exist if you can't measure it? The math that describes the interactions of particles says that the virtual particle exists. It has to. But it only exists long enough for the math to work. They can be visualized by [Feynman Diagrams]( URL_0 ), which show the interaction of particles. This one shows two electrons coming near each other, exchanging a virtual photon, and then leaving the interaction. The squiggly line is the virtual photon. Notice that the photon doesn't leave the diagram. It goes from one electron to the other, but it doesn't go in or out. It can't. If it did, it could be absorbed and detected somewhere else. Anything in the middle of a Feynman Diagram like that is a virtual particle. Also worth noting slash just kind of neat: virtual particles don't just go from one place to another or \"exist\" in a continuous, rational kind of way. That virtual photon might spontaneously become an electron-positron pair, and then those will annihilate each other again to become the photon. The virtual photon can take literally any possible path through space to get from one electron to another. And an electron can spontaneously emit a virtual photon and then reabsorb it again. Any of those things can happen any number of times, and it doesn't change the outcome of the interaction between the original two electrons which are the real particles. Anything in-between is virtual."
],
"score": [
39
],
"text_urls": [
[
"https://sciencevspseudoscience.files.wordpress.com/2011/12/moller_feynman_tree.png"
]
]
} | [
"url"
] | [
"url"
] |
7fhlz7 | Why is using a PC in a darkroom bad for your eyes even though it feels nicer than a fully light room at night? | Biology | explainlikeimfive | {
"a_id": [
"dqbwyvm",
"dqbx9q7",
"dqby5f9",
"dqbydui",
"dqbx9ll",
"dqc159j"
],
"text": [
"It's bad for your eyes in that the difference in brightness levels from the monitor to the rest of the scene can result in eyestrain. Monitors can also contribute to eye strain in general by forcing the muscles of your eyes to do a lot of work focusing and moving. Note that this is bad for your eyes in the sense that it is uncomfortable, it is not bad for your eyes in the sense of causing any sort of permanent damage or worsening your vision.",
"A solution for this is a program called flux, it changed the hard blue of the monitor to a much better orange which is much easier on your eyes. I work on my pc at night and its amazing the difference.",
"It isn’t. The idea that using a TV or computer screen in a dark room is bad for your eyes dates back further than computers, to the early days of television. It was a myth fabricated by...wait for it... A lamp manufacturer.",
"Note: a darkroom and a dark room are two different things. A PC in a dark room is bad for your eyes. A PC in a darkroom is bad for the film and photographic paper you are processing.",
"You don't need the whole room to be lit, and you don't need it to be overly bright, but ideally, you want the area around your monitor to be a similar brightness to reduce eye strain. This is why a lot of people put a small light behind their monitor. Also \"darkroom\" - > \"dark room\".",
"Looking at the shitstorm further up, I don’t want to add to it, but I am curious if any long term studies were done...not on computer monitors specifically but on the high contrast fixed distance thing. With TV, booklights, flashlights under the sheet, etc. having been around, we should have plenty of case material. The idea that forcing the eye muscles to work repeatedly on the same difficult task will damage them seems counter-intuitive to me because that same process in almost (if not) all other muscles in the body strengthens them. How do we know whether we’re damaging our eyes or exercising them?"
],
"score": [
286,
57,
30,
16,
10,
3
],
"text_urls": [
[],
[],
[],
[],
[],
[]
]
} | [
"url"
] | [
"url"
] |
|
7fhnlt | How does our brain create a mind? | Other | explainlikeimfive | {
"a_id": [
"dqbvtpx",
"dqbyuha",
"dqc1n4u",
"dqbwayk",
"dqbz2d3",
"dqc0fsw"
],
"text": [
"This is a question no one knows the answer to, there are plenty of theories about what it could be though.",
"I have a degree in Cognitive Science, and I can assure you that nobody knows. Not even close. It's often debated whether it is even possible for us to know.",
"One theory is that there are tiny magnetic fields around each one of the brain's ~100 billion cells (aka neurons, which themselves are very highly interconnected). As the neurons activate (as information flows through them) these little magnetic fields interact and add up with one another as well as subtract. It is theorised that in this interaction, the mind, consciousness and many other interesting things exist. If you wish to know more about this, the topic is Holonomic brain theory.",
"Your brain is like a big jar of jelly with a lightening storm inside it. These little wire-like things live in the jelly and kinda keep the lightening going in the same general shapes. The bit that's *you* isn't the jelly, isn't the wires, it's the storm and how it rumbles around inside. Now, who wants a PBJ?",
"There's no guarantee that the brain creates the mind. It's also possible that the mind (conciousness) is what creates reality as we know it for each of us - including the brain. Whatever actual objective reality might be like has no reason to be the same three dimensional space as we experience it. Here's an interesting presentation about all of this: URL_0",
"I don't doubt there is an answer to this, the problem arises when the confines of all currently used languages are employed when attempting an explanation. All known language today is highly interpretive (it's how politicians make a living essentially), until we create a language where we mean precisely what we say (with no room for interpretation or pondering) these sorts of questions are rigged for failure essentially. The \"mind\" itself is just a word for something we barely have an explanation for. I doubt the brain can be easily surmised into a four letter word. Also, the fact we don't fully understand all of the brain's workings; makes it impossible to make satisfactory commentary on \"the mind\"."
],
"score": [
156,
113,
9,
6,
4,
3
],
"text_urls": [
[],
[],
[],
[],
[
"https://www.ted.com/talks/donald_hoffman_do_we_see_reality_as_it_is/transcript"
],
[]
]
} | [
"url"
] | [
"url"
] |
|
7fhsz7 | Why is it such a difficult task to locate and rescue a malfunctioning submarine at sea and why can't all the sailors escape safely via the torpedo tubes in pressure suits? | These questions came to my mind in light of the recent San Juan disaster. | Technology | explainlikeimfive | {
"a_id": [
"dqbxjdj",
"dqbxfs8",
"dqbykif"
],
"text": [
"The ocean is *big*. Incredibly big. And huge swaths of the sea floor haven't been mapped. You're talking thousands upon thousands of square miles to look through, except you can't just look. You have to use sonar instead. Is that roundish bump that showed up on the sonar the nose of a submarine? Or is it just a roundish rocky bump on the bottom of the sea floor? Is the sub not in this area, or was it just in the shadow of a rocky underwater ledge so your sonar couldn't hit it? Is the submarine even still in one piece, or is it in pieces? How many pieces? Did the pieces settle on the bottom together, or did an ocean current drag different sections miles apart before they hit the bottom? Did the submarine continue on a straight course, or did it get caught in a current? Did the engines or props or rudder malfunction, so that it veered off course? When? By how far? You're basically looking for a needle in a haystack after a storm blew your haystack all over the place and also you're not allowed to look for it, you just have to poke around with your finger until you find it, and also it could just as easily be in your neighbor's haystack. There aren't pressure suits on board. You can't carry enough for every sailor, and it would be impractical and expensive to carry the right kinds, especially since at some of the depths a sunken sub would end up in, a suit wouldn't help you. There are hatches and small oxygen tanks and flotation devices to get you out, but you have to get to those. There's no guarantee that the sub isn't already flooded in the corridors between you and any of those things. Sure, you could open up the torpedo tubes, *if* you are close enough to them, *if* that room isn't already flooded, *if* you can get the tubes open, *if* the sub hasn't already sunk too deep for you to escape without help...",
"The ocean is incredibly large. Subs are designed *not* to be heard/found. There are too many crew members. Torpedo tubes aren't designed as escape hatches. There are no \"pressure suits\" to combat the pressure at depth, which is to say nothing of the cold, dark of the water and sheer length of time it would take to reach the surface only to get \"the bends\" (nitrogen narcosis) without anyone, or anything their to rescue them at the surface.",
"Pressure suits aren't carried, but there are escape suits that can be used. The submarine I went to sea in (Oberon Class) was equipped with two escape towers(also known as trunks). These allow one person at a time to escape the sub. It takes time to cycle them, if a boat is sinking in very deep water, there will not be time for anyone to get out before it reaches crush depth. If you are lucky enough to end up on the continental shelf, It is a different matter altogether. The preference of course is to wait for DSRV(Deep Submergence Rescue Vehicle) rescue. If the boat becomes pressurized, or is too deep, then there is a risk of getting the bends. As /r/Geetarzkool has stated, the world's oceans are a very big place, and if something catastrophic has occurred, the beacon a Sub carries may be damaged or rendered inoperative. In a perfect world an EPIRB (Emergency Position Indicator Radio Beacon) is released and will transmit on radio. I do not know if the Argentine sub was equipped with such a device, but we had one, and it was set on a timer that had to be reset every few hours, or it would automatically launch. When things go bad on a submarine, they can go very bad very quickly."
],
"score": [
37,
8,
8
],
"text_urls": [
[],
[],
[]
]
} | [
"url"
] | [
"url"
] |
7fi0zq | What determines how hard a fighter punches is it down to bone density or do muscles and frequent practice help | Physics | explainlikeimfive | {
"a_id": [
"dqbzivg"
],
"text": [
"As with all force, it’ll come down to mass and speed. The mass of the punch isn’t just the fist or arm, but all of the fighter in motion, from their anchor point. That is, the whole of mass behind the punch. If the fighter truly just moves their arm, it’s mostly the mass of their arm, for example. A fighter punching through their torso, as in by swiveling their hips, gets the mass of their moving upper body, too. This isn’t all that goes into it. The speed of the moving arm contributes to the force, too. A faster movement gives more punch to the punch. That still isn’t all. Once there’s contact, then the resistance of what the fighter has hit, and the fighter’s ability to hold against the punch factors in, too. This, as a simple example, is the force you see when you simply push against something without hitting it; how much it moves versus how much you move as you push with your arms. The strength of the fighter goes into this a lot. Stronger fighters can have faster punches and provide that post-impact resistance. Practice goes into this in a lot of ways, including conditioning for strength, endurance, accuracy, and more."
],
"score": [
8
],
"text_urls": [
[]
]
} | [
"url"
] | [
"url"
] |
|
7fi6fy | What's happening to your taste buds when you eat a really hot pepper? | Biology | explainlikeimfive | {
"a_id": [
"dqc7qlz"
],
"text": [
"The main ingredient that makes chili hot is capsaicin. It activates a receptor called TRPV1 which also gets activated by heat and physical damage to the cells. This means that your brain interprets it as if your mouth is being scalded."
],
"score": [
4
],
"text_urls": [
[]
]
} | [
"url"
] | [
"url"
] |
|
7fi8em | What is a Hilbert Space? | One of the strikes (read: dungeons) in Destiny 2 involves storming a Hilbert Space populated by time-travelling robots, but I've no idea what a Hilbert Space even is. | Mathematics | explainlikeimfive | {
"a_id": [
"dqc4qyn"
],
"text": [
"Never played Destiny 2, but if it has Hilbert space reference, I now kinda want to. Anyhow, to describe Hilbert space, but omitting mathematical details, you kinda can just take your intuition about what a space even is(assuming you aren't mathematician. If you are, then you're thinking too broadly), and consider for example sheet of paper as 2d space. Or our world we live in as 3d space. Or piece of string as 1d space. Hilbert space is a catch-all name for these spaces, and some more. You can have 4d Hilbert space, or 5d Hilbert space, but also the thing that really makes it a bit weird is that even infinite-dimensional spaces are allowed. If one speaks of **the** Hilbert space, you refer to the infinite-dimensional case. The cool bit about Hilbert spaces is that infinitely many dimensions breaks surprisingly few of our intuitions. There's still concept of distance between points, you can still do sorta geometry in this space, and you can even do calculus in infinite dimensions. How you arrive at them is basically, imagine infinite dimensions. Then try to figure out how to calculate distances between points without everything being infinite(for comparison, distance on a straight line is |x1 - y1|. Distance on a plane is sqrt((x1 - y1)^2 + (x2 - y2)^2 ).) And boom, you're more or less done. Technical details left as an exercise for the reader."
],
"score": [
7
],
"text_urls": [
[]
]
} | [
"url"
] | [
"url"
] |
7fib7w | Why are social values and economic policies conflated in American politics? | Other | explainlikeimfive | {
"a_id": [
"dqc0w1m",
"dqc2ztf"
],
"text": [
"America was founded by Calvinist theocrats, Protestants (some of whom were theocrats), and Catholics (who founded Maryland specifically as a haven for Catholics). Personal values have always been a facet of American politics.",
"Unlike nations that have a long history, that have matured through all the events that old nations/societies do. The US is just breaking through the infantile stage. Culture comparatively is nonexistent (as culture is intrinsically linked with the passage of much time). America has only seen very few conflict (the harsh, but common growing pains of a nation that fought for autonomy and eventual independence), but aside from that, there are no \"life lessons\" applied unto the American public. Sheer determination and intellect is what got America bootstrapped into becoming a world power in almost no time at all. This is in part thanks to the vast amounts of lands that were ripe for the taking by profiteers across the ocean and at home at the time. The general population on the other hand has barely walked out of the swamps/forests they used to build their homes almost 200 years ago. Where tradition and religion ruled back then, it essentially still does today. One thing most Americans resonate with is, not losing their heritage(and freedom to practice whatever they want unbothered), so the same beliefs and customs/religious rituals survive still today in the parts outside of cities. Thus politics, and day to day life was always linked, (as you can see the heavy Christian presence in rallies and speeches, even though technically, the founding of this nation had many people implore the separation of church and state to no avail). The problem with distancing yourself away from 'American Values' in politics, is you're essentially distancing yourself from the people. Keep in mind, the qualities of American culture/society as I said is not a fine wine like old nations of Europe/East Asia for instance. Now going back to distancing yourself from those values: that is basically distancing yourself from the very little common ground you DO have as an American, and basically becoming an outsider. The most ardent Americans for instance if you were to strip away their tradition and culture; suddenly feel like aliens, belonging nowhere specifically speaking. They need a place to call their own one way or another, so they carry on with whatever the generations of the past have done and believed. As for the economic policies. That is even simpler, as the \"American Dream\" and \"independence\" and \"freedom\" are all essentially economic undertones of the same message: Economic freedom. The vast majority of people in America have been prey to the economic revolutions of the past generations of business practices. When you have a nation where you can \"make a life of your own\" and you had places called the \"Wild West\", you inevitably have a subset of people willing to do anything to \"make it\", and American business is plagued with instances of abuse of some level in every decade of American history. The whole dream is derived from their examples (Vanderbilt/Rockefeller etc..), and most hold them as heros of industry and history in America. Thus economic policy is then married with social values like so: No one in America wants their social and civil freedoms infringed upon, and their path for striving for the American Dream must never be blocked otherwise they see that as an affront to their self-worth as an American. So with one stone, you now hit two birds, socially placate the majority of the population - while at the same time reassuring potential businessmen and investors in and out of America, that America is a great place to invest and generate success for yourself. Never has this been more apparent than now with business essentially creating a religion of superficiality and value based on spending power. Meaning: If you can buy more than the other person next to you; you then have a life more valuable and more fulfilling that that other person (according to the ruling paradigm of today's current generation of business marketing conglomerates). Many people take issue with criticisms of saying \"America little history/social/cultural wealth. They forget this is only comparatively speaking with nations in the same period. It's not an insult, it's just the way things were/are. There's not much to argue over while we here in America were hunting bison on the great plains/playing the banjo on the backyard porch, Mozart at the same time in Austria was composing some of the greatest works of music. To end this rabbit hole.. There is nothing wrong with American progress in terms of how far we've come, this was only side commentary the came as a result of trying to explain this topic."
],
"score": [
9,
5
],
"text_urls": [
[],
[]
]
} | [
"url"
] | [
"url"
] |
|
7fj7ci | Why do humans have temperature sensors in our stomach? | Biology | explainlikeimfive | {
"a_id": [
"dqc94o9"
],
"text": [
"Human beings sense the temperature of food with their mouths, not with their stomachs. If you have a sensation of heat in your stomach, what you are sensing is acidity, not temperature. Excess stomach acidity causes a burning sensation."
],
"score": [
3
],
"text_urls": [
[]
]
} | [
"url"
] | [
"url"
] |
|
7fjb5y | Why do people lose their voice? | Biology | explainlikeimfive | {
"a_id": [
"dqc99gk"
],
"text": [
"Voice is the result of moving air past muscles and tissues that restrict and interact with the air. Losing your voice is because these muscles and tissues are not entirely working. They may be fatigued, stretched, inflamed, stiff, or otherwise impaired. If you can whistle, you can reproduce this by trying to whistle with your lips too loose or tight or dry or impaired with fingers or tape or something..."
],
"score": [
5
],
"text_urls": [
[]
]
} | [
"url"
] | [
"url"
] |
|
7fje5p | Can countries do the opposite of a state seceding? For instance, could the US "kick out" one of its' states and force it to become its own country? | Couldn't find anything about this upon searching. Thanks in advance! | Other | explainlikeimfive | {
"a_id": [
"dqc9wws"
],
"text": [
"Yes. In fact there have been nations that have been formed because they were kicked out. Singapore is an example - they got kicked out of Malaysia. In the context of the US, there is no way in the US constitution for a state to be expelled from the union. Any attempt to do so would require an amendment of constitution. Actually, if the circumstances were ever such that a state needed to be kicked out for some hypothetical reason, it's likely that there would be a constitutional crisis."
],
"score": [
31
],
"text_urls": [
[]
]
} | [
"url"
] | [
"url"
] |
7fjfcj | When you bring a magnet near a ferrofluid, why does it spike up like it does? | Physics | explainlikeimfive | {
"a_id": [
"dqcayzf"
],
"text": [
"The ferrofluid is basically iron filings in oil. The iron filings are trying to fit themselves into the field of the magnet but are limited by the surface tension of the oil so they form large spikes instead. They can’t get away from each other enough to form the intricate patterns of the polar arcs."
],
"score": [
3
],
"text_urls": [
[]
]
} | [
"url"
] | [
"url"
] |
|
7fjhxg | what does the US national debt actually mean to the average American? | The US national debt is already the largest of any country in the world. What are some scenarios that could occur if the debt is not paid down or continues to rise, and how will the average American be affected? | Economics | explainlikeimfive | {
"a_id": [
"dqcadmu",
"dqccdhr"
],
"text": [
"Next to nothing. Having a large debt does not matter if you can make the payments on said debt. The US has never missed a payment and if the economy was tanking hard enough for it to miss a payment there would be far greater concerns for the average American.",
"It means a tremendous amount to the average working American, actually. Out of every tax dollar paid 6% goes into interest payments. Not rebuilding infrastructure, not the military, not to short up Social Security, medicare, etc. It's blown on nothing but interest on the debt. The government needs $X plus 6% just to run. Unhappy with your taxes? Just think - if we did not have this massive debt, you could be paying 6% less in taxes. Never, ever let anyone tell you the debt doesn't affect you. It does, every single paycheck. EDIT: in 2015 it was 6%. No idea where I got 25. Changed to match those figures."
],
"score": [
8,
3
],
"text_urls": [
[],
[]
]
} | [
"url"
] | [
"url"
] |
7fji4t | What is the difference between a psychopath, a narcissist, a sociopath, and a sadist? | Biology | explainlikeimfive | {
"a_id": [
"dqcatnd",
"dqcawg3"
],
"text": [
"Psychopath and sociopath are coloquial terms for what is currently the same diagnosis: antisocial personality disorder. This is most notably characterized by an extreme lack of empathy and manipulative behaviors. Narcissism is an inflated sense of self-worth and self-importance. Sadism is taking pleasure in causing pain or suffering in others.",
"There can be similar behavior resulting from all of these conditions, therefore it is not always obvious what the correct diagnosis is. However, the conditions themselves have clear definitions. A psychopath is an insane person who is not in touch with the real world, suffers from serious delusions and has a limited or damaged capacity for logical reasoning. A narcissist is a person who is obsessed with himself or herself and sees all other people as tremendously less important. A sociopath does not have the ability to empathize with other people - in practice, this closely resembles narcissism. A sadist is a person who takes pleasure from the pain and suffering of others, often in a sexual context. Note that there is what might be described as a complementary condition known as masochism. Masochists derive sexual excitement from being abused in various ways (the particular abuse that they want varies a lot by individual). As a result, a sadist and a masochist have the potential of forming a sexual partnership, and of making each other happy by doing exactly what they want to do. So even though sadism seems like an inherently destructive state of mind, it is possible to practice sadism in a way that is socially responsible. Not all sadists are socially responsible, but some are. These conditions can also be combined with each other. The more of these conditions someone has, the more destructive their actions are likely to become."
],
"score": [
10,
5
],
"text_urls": [
[],
[]
]
} | [
"url"
] | [
"url"
] |
|
7fjif1 | Why are diseases like yellow fever not curable? | Biology | explainlikeimfive | {
"a_id": [
"dqcaoqm",
"dqcaoeu"
],
"text": [
"TIL that yellow fever is a real disease and not just an attraction to Asians. They are not curable simply because no one has found a cure for them yet.",
"Every disease that infects you is able to do so because it has some way of evading your immune system. A lot of the time, your immune system will learn to deal with it, and you get better. But sometimes the disease is too good, or for some reason your immune system isn't as well equipped to deal with that particular illness (having antibodies to some types of flu virus make you more vulnerable to different types of flu, for example), and you don't get better. Cures are generally drugs that target the disease so thoroughly that it is all gotten rid of. Antibiotics stop metabolic processes that bacteria do, but our own human cells do not, and this is how they effectively cure bacterial illnesses. Viruses like yellow fever, on the other hand, do not have any metabolic processes, so we need to use different drugs that target things like viral proteins that our own cells don't make. But for some diseases, we haven't managed to formulate any medicines that do this. A surprising number of diseases are treated by dealing with symptoms, rather than the disease itself. For example, there is no cure for the common cold, and every \"treatment\" is really just soothing the symptoms while your immune system learns how to deal with the cold virus,"
],
"score": [
5,
3
],
"text_urls": [
[],
[]
]
} | [
"url"
] | [
"url"
] |
|
7fjm2c | Why does the US Federal Reserve want to raise intrest rates if unemployment falls below 4%? | Economics | explainlikeimfive | {
"a_id": [
"dqcbhho",
"dqcemcl"
],
"text": [
"The Fed has a dual-mandate: keep unemployment low and keep inflation low. Generally economists think that the US is at full employment if the unemployment rate is around 4%. This is because you figure that at any point in time you have about that many people \"frictionally\" unemployed. Meaning they are moving from one part of the country to another, want to change careers, just caught a bad break, etc. They are no unemployed because of it being systematically hard to find a job. Once the economy hits full-employment, the Fed gets very worried about inflation taking hold in wages. If the economy continues to grow, employers will start bidding up wages even though there are no more people to hire. In essence, wages would increase without an increase in productivity, and thus inflation would be transmitted through out the rest of the economy. (This is essentially what happened in the 1970's and was a huge problem.) So they start raising rates to slow growth and prevent wage inflation.",
"Moderate inflation is good for the economy as it results in more money to employees = > increased consumer spending = > increased production = > increase in GDP."
],
"score": [
10,
4
],
"text_urls": [
[],
[]
]
} | [
"url"
] | [
"url"
] |
|
7fjoli | How come most (or all) TV remotes are black? | I just realised I’ve probably never seen a tv remote in any colour other than black (and I sold TVs for a year). How come? Are they easier to find around the house that way? | Technology | explainlikeimfive | {
"a_id": [
"dqch6zo",
"dqcbr84"
],
"text": [
"TV remotes are colored to match the TV they go with. Recently, consumer electronics (such as TVs, stereos, etc.) have all been black. Black is a great color, because it doesn't clash with most home decors. Black has been the most fashionable color for a while. In the 80's the color of choice was silver/grey. In the 70's it was fake wood paneling. (And I've seen remotes with fake wood paneling stickers. Really.)",
"It's only older television sets/VCRs I had that were lighter. Usually grey. I once had a silver TV/VCR combi in silver and it had a silver remote. I'd say when lcds came on the scene was when most started being black. Not sure of the reason, maybe to stop them looking dirty as easily? Stop discoloration (see also: nintendo snes yellowing)"
],
"score": [
15,
3
],
"text_urls": [
[],
[]
]
} | [
"url"
] | [
"url"
] |
7fk0x5 | How do we know the Earth is fluid inside and why do we think we know the temperature of the core as well as the kind of metal it consists of? | Other | explainlikeimfive | {
"a_id": [
"dqcf7nt"
],
"text": [
"Seismic waves travel through rock in much the same way that sound waves travel through air. By measuring seismic waves, scientists can identify the composition of Earth's subsurface layers. Because the layers are made up of different materials that vary in thickness, they are able to analyze the ways in which seismic waves bounce off the boundaries between various layers. As for temp, scientists are making an educated guess. They know the material (iron mostly) the state (molten or solid) and the amount of pressure the material is under. So the equation is what temp would iron under that amount of pressure be?"
],
"score": [
4
],
"text_urls": [
[]
]
} | [
"url"
] | [
"url"
] |
|
7fkabb | How is binary read? Especially the numbers. How is 10010 the number 18? Is there an algorithm or is it more complex like learning a language with letters? | Technology | explainlikeimfive | {
"a_id": [
"dqcgapk",
"dqci86y"
],
"text": [
"its very simply read in 'columns'. each column is worth a value. you add the values together anywhere there is a '1'. example; 10010 is actually like 16 | 8 | 4 | 2 | 1 so there is a '1' in column 16, and a '1' in column 2. what is 16+2 = 18. that's literally all it is.",
"The fastest way to learn binary is to *really* learn base 10 (\"normal\" counting). When you count you go 1, 2, 3, 4, 5, 6, 7, 8, 9, *what*? What happens when you run out of digits for one-digit numbers? You wrap around to 0 and put a 1 in the next place, giving 10. Then you go back to incrementing the lowest place value: 11, 12, 13, 14, 15, 16, 17, 18, 19, *what*? You reset the last digit to 0 and increment the next digit again, giving 20. That pattern continues when you run out of digits in the next place value: when you try to count past 99 you need to reset the ones place to 0 and increment the 10s place, but the 10s place is already 9 so you reset that to 0 and increment the next digit, giving 100. When you look at a big number, say 8,675,309 you can recognize that as 8\\*1,000,000 + 6\\*100,000 + 7\\*10,000 + 5\\*1,000 + 3\\*100 + 0\\*10 + 9\\*1. Each place value is worth 10 times the one before, since we're in base *10*. For binary just forget that the numbers 2-9 exist. You start counting and you only get to 1 before you're out of digits. You have to reset to 0 and increment the next place value (the 2s place now). That gives you 10, then you count one more to get to 11 and you're out of digits again. Counting to 8 in binary looks like 1, 10, 11, 100, 101, 110, 111, 1000. With each step you increment the last digit by either turning a 0 into a 1 or rolling a 1 back into a 0 and incrementing next digit (following those same rules). Also, like with base 10, you can find the value of a number by counting up the contribution from the individual digits. The number 10010 is 1\\*16 + 0\\*8 + 0\\*4 + 1\\*2 + 0\\*1 = 16+2 = 18."
],
"score": [
13,
3
],
"text_urls": [
[],
[]
]
} | [
"url"
] | [
"url"
] |
|
7fkarf | why do our recorded voices sound different to us but normal to everyone else? | Or am I just weird? | Biology | explainlikeimfive | {
"a_id": [
"dqcqxnj"
],
"text": [
"Imagine your eardrum inside your ear to be a small trampoline. Every time you sound reaches it, it vibrates just the way a trampoline does when you jump on it, and then it sends a signal based on the vibration, to your brain, to tell you what the sound was. Now imagine every time you jumped on a trampoline, there's some vibrating thing underneath the trampoline, or your dad hit the trampoline from the bottom. That's what the bones and the reflecting vibrations inside your ear do. Remember that sound also reflects (as echo over mountains, for example). The trampoline now doesn't know whether the signal that it should send to the brain should be about you jumping or your dad hitting the trampoline. So it sends both and the brain merges them. This makes you hear a combination of two sounds now, both at the same time. The combination is obviously different from the sound you make that your friends will hear."
],
"score": [
4
],
"text_urls": [
[]
]
} | [
"url"
] | [
"url"
] |
7fkbb2 | Why is it that blowing on a lit candle causes it to flicker but not go out, but a single puff of air is more effective at extinguishing the flame? | Chemistry | explainlikeimfive | {
"a_id": [
"dqcgu9o"
],
"text": [
"Because unlike a campfire that uses a solid object (wood), a candle actually only burns the wax while it is in the gas state. When you blow out a candle, immediately after it is extinguished you’ll see a small trail of ‘smoke’. This tiny trail is not actually smoke, it’s wax vapour. This vapour is also the reason why a candle can be relit using a lit match that doesn’t touch the wick. (Seriously, go try it) When you blow a puff, you remove the vapour (fuel) flowing up into the flame. A soft blow still allows the wax vapour to feed the flame, hence it flickers or dances in a breeze."
],
"score": [
12
],
"text_urls": [
[]
]
} | [
"url"
] | [
"url"
] |
|
7fkgde | What part of our brain controls our internal clocks and what is happening when it seems to be “out of sync” for some people on long holiday weekends? | Biology | explainlikeimfive | {
"a_id": [
"dqcjxf9"
],
"text": [
"Our internal clocks are controlled by the Hypothalamus region of the brain, and they help control our circadian rhythm, but this rhythm is also affected by environmental cues, the most significant of which is daylight. The circadian rhythm controls your bodies release of hormones and helps regulate sleep cycles, as well as other habitual factors. Holiday \"out of sync\" feelings, are similar to Jet Lag, you are experiencing environmental cues that aren't lining up with your internal clock's release of hormones, your inner clock can and will adjust eventually but it's not an instant process and takes time and repetition. So imagine if you are normally most active in the mornings, your body is regulated to increase your overall energy during this time period, and around evening it released hormones like melatonin to help you relax and prepare for sleep. During long weekends, this tends to reverse, and your periods of high activity are generally more towards the latter half of the day rather than the beginning, so even if you try to \"conserve energy\" by relaxing or sleeping in early in the day, your body clock is thrown off and it's still releasing hormones telling you that you need to be winding down when you are trying to be the most active and sociable. URL_0"
],
"score": [
8
],
"text_urls": [
[
"https://www.nigms.nih.gov/education/pages/Factsheet_CircadianRhythms.aspx"
]
]
} | [
"url"
] | [
"url"
] |
|
7fkp3j | How can you be below sea level and not underwater? | Sorry if this is a dumb question; I know this is a thing but the terminology confuses me. Thank you!! | Other | explainlikeimfive | {
"a_id": [
"dqcjmf0",
"dqcjj5m",
"dqckluk",
"dqcknbz"
],
"text": [
"Go somewhere that is 100m above sea level. Dig 200m straight down. Congratulations, you are now 100m below sea level! That's how places that are below sea level work, except that most of them are valleys that formed naturally.",
"Dams, natural or man made block water. Thats it really. The nederlands for example has huge dikes surrounding the sea area.",
"Good example is Death Valley. It's landlocked and in a desert and below sea level. There's no water to flood and fill the basin.",
"Drive to the city of New Orleans. It’s between 5 and 15 feet below sea level for the most part. Levees that were built and are maintained by the Army Core of Engineers keep back water in the Mississippi River and in Lake Pontchartrain. I should note that New Orleans has its own problems with drainage and pumping. Foundations usually require pylons to be driven into the ground to stabilize the building, and graves must be above ground, because water will fill any holes that are dug."
],
"score": [
16,
6,
6,
3
],
"text_urls": [
[],
[],
[],
[]
]
} | [
"url"
] | [
"url"
] |
7fkvy5 | Why are the pockets on brand new suits and some other types of clothing sewn shut? | Other | explainlikeimfive | {
"a_id": [
"dqcneu7"
],
"text": [
"For several reasons. It helps make sure that the suit keeps it's correct shape during the final steps of manufacturing and the pressing (ironing). Also it is done to help the suit look better while it is on display in the store. And it keeps everyone else's grimy booger hooks out of the pockets until the proud new owner cuts open the pockets for the first time."
],
"score": [
5
],
"text_urls": [
[]
]
} | [
"url"
] | [
"url"
] |
|
7fm5ku | How do they make 100 year old pictures look like they were taken yesterday, also, old movies, how do they look 1080p | Technology | explainlikeimfive | {
"a_id": [
"dqcstlu"
],
"text": [
"Old movies (most movies in fact) are shot on film, which is analogue and therefore doesn't have a resolution as such. The resolution is only restricted by what you transfer it to (Video, DVD, Blu Ray etc). Therefore if the original film master exists, you could create a new version in pretty much whatever resolution you want."
],
"score": [
21
],
"text_urls": [
[]
]
} | [
"url"
] | [
"url"
] |
|
7fm8eh | Europes AC electricity has a frequency of 50hz instead of 60hz. Is it still possible to get 60fps on televisions and monitors? | My father keeps telling me that it is impossible to get a monitor refresh rate of 60 in europe, telling me that because our AC has 50hz the standard for fps is also 50fps. I believe his knowlegde may be out of date. So my question is: How does the frequency of alternative current correlate with the refresh rate of monitors? | Technology | explainlikeimfive | {
"a_id": [
"dqctdad",
"dqctrf1",
"dqctzv5",
"dqctbnj"
],
"text": [
"Back in the days of analogue TV, refresh rates were tied to the frequency of AC power. This is why PAL televisions were based around 25/50 Hz instead of NTSC's 30/60. These days, it's not relevant. Wall current is converted to DC before it feeds into the monitor where it drives a frequency-generating crystal to figure out how everything else works. The adapter on my laptop will run on anything 50-60Hz and 100-240 Volts and still provide a constant 19V output.",
"In the days of the CRT monitor, (those massive boxes that flickered and were always staticy), the refresh rate was directly controlled by the AC frequency it was supplied with. So in Europe, your lightbulbs flicker at 100hz, and your CRT's flicker at 50hz. And in North America, our lights flicker at 120hz and CRT's at 60hz. In digital monitors and TV's, the AC electricity coming from the wall is converted to DC before anything happens. For digital, the refresh rates are usually locked to what the manufacturer specified. The frame rate of your computer has no connection to the AC frequency so there is no need to worry about that, your computer can output any frame rate it can handle. *(Sometimes it is converted outside the monitor, on those you'll see a black box on the line that looks like a laptop charger. Other times the converter is placed just inside the device so for \"neatness\")",
"Your father is thinking of older CRT monitors. Essentially, these work by firing a single ray at the screen. Electromagnets deflect this ray so that it scans in horizontal lines from top to bottom, while the ray itself is switched on and off rapidly (colour monitors had three guns, one for each primary colour, but the basic principle was the same). Each frame is therefore scanned from top to bottom, and this is timed using the mains frequency, which is 50 Hz in Europe but 60 Hz in North America. But because of the fact that high frame rates weren't easily possible in those days coupled with the way human vision works, each frame was scanned twice, alternate lines each time, so you actually got 25 fps in Europe and 30 fps in North America. (Actually, because of bandwidth problems with the NTSC system used in North America, when colour was introduced they had to slightly slow the frame rate to 29.97 fps -- the reason for this is highly technical and not easily ELI5-able.) This isn't relevant at all these days, because monitors and TVs work on completely different principles. Instead of using mains frequency to time everything, monitors have their own internal clocks, and the cathode ray tube monitor is now rarely seen outside of a museum -- thankfully: those things were massive, weighed a ton, and if they broke would send shards of glass flying about the room.",
"The frequency of your AC electricity has nothing to do with how fast your monitor can refresh. 120+ Hz monitors exist after all."
],
"score": [
14,
5,
4,
3
],
"text_urls": [
[],
[],
[],
[]
]
} | [
"url"
] | [
"url"
] |
Subsets and Splits
No community queries yet
The top public SQL queries from the community will appear here once available.