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j21c7x
|
Why are headlights on automobiles pointing more upwards and towards other drivers than towards the road?
|
Technology
|
explainlikeimfive
|
{
"a_id": [
"g72ilny",
"g72j77l"
],
"text": [
"You need them pointed high enough to illuminate road signs at night. All those road sign paints are \"retroreflective\", they send light back the same direction it came in from, but you need some illumination on them to see them. A properly aimed headlight should be aimed slightly down to illuminate the road for several hundred feet in front of the vehicle, but you need side and up lobes bright enough to illuminate parked cars, other cars, signs, etc. The brightest part shouldn't be aimed at other drivers...that's why high beams look so much brighter, they \\*are\\* aimed way closer to other drivers.",
"They're not? A properly adjusted headlight beam should actually aim slightly away from oncoming drivers. Park with the nose of your car facing toward a wall and you should see this."
],
"score": [
8,
3
],
"text_urls": [
[],
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|
[
"url"
] |
[
"url"
] |
|
j21emv
|
Why are horses still so sound-sensitive, even though they were used in wars years ago? How could they have been used in wars?
|
Biology
|
explainlikeimfive
|
{
"a_id": [
"g72j10t",
"g72no6h"
],
"text": [
"They were trained. Horses aren't natural soldiers any more than people are. They had to be exposed gradually to the sights and sounds of battle, and taught what to do. There's a video on YouTube of a guy who demonstrates this; I'll see if I can find it. Here's one and I think he has a few more. URL_0",
"Desensitized training is what is commonly used for both horse s dogs and humans in regards to war combat violence etc etc"
],
"score": [
19,
3
],
"text_urls": [
[
"https://youtu.be/xKi8GQSnvaU"
],
[]
]
}
|
[
"url"
] |
[
"url"
] |
|
j21ix3
|
How does a Perm actually work?
|
I always wondered how the hair is able to stay curled for so long. What do they use and why does it work??
|
Chemistry
|
explainlikeimfive
|
{
"a_id": [
"g72o5xu"
],
"text": [
"Hair is basically a big structure of tangled up proteins (long thin molecules). Imagine you take a bowl of cooked spaghettti, toss it all with some jello, arrange it in a big rope shape, and let it dry...that's kind of like hair. If you let it dry straight, it'll stay straight-ish, if you let it dry in a circle it'll stay curled-ish. A perm is basically dissolving the glue, reshaping the hair in a different shape, then re-gluing it in the new shape. You're literally reshaping the hair fibers from straight to curly. First, add a chemical to break down the bonds between hair proteins. Wrap the hair in curlers so it's the shape you want. Add chemicals to rebuilt the bonds between hair proteins, still in the curled state. Let it all set. Remove curlers. Tah dah...curled hair. It will stay that way \"forever\". BUT...the hair follicles don't know you did that. They continue growing whatever hair they always did, so the perm will grow out, that's why you have to redo it periodically, to recurl the new hair (and reset the already curled hair to match)."
],
"score": [
5
],
"text_urls": [
[]
]
}
|
[
"url"
] |
[
"url"
] |
j21zek
|
why is it hard to keep the eyes open when you’re so sleepy? Does keeping the eyes open requires that much effort?
|
Biology
|
explainlikeimfive
|
{
"a_id": [
"g730a0f"
],
"text": [
"Your eyelids are controlled by muscles, and like any muscle in your body they can get tired. Your whole body was more or less designed to stay awake a certain amount of time. So your eye lids have enough strength in them to stay open for that amount of time. Your arms and legs should also feel pretty heavy by the very end of the day. Most of your brain is turning down the power to various parts of it, making it more of a conscious effort to work to do things that were usually more automatic or subconscious."
],
"score": [
7
],
"text_urls": [
[]
]
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|
[
"url"
] |
[
"url"
] |
|
j229t4
|
Why the taxes aren’t included in the final price in the US?
|
Economics
|
explainlikeimfive
|
{
"a_id": [
"g72pq31",
"g72rc4c",
"g72p2yj"
],
"text": [
"It's simpler to just show the base price and everybody knows that taxes will be charged on top of that... How do you advertise the price when it's different in every city/county/state? How does an electronics store advertise a TV that's $599 (plus tax) when it's $637 in one town, and $640 in another, and $628 in another that all get/see the same ad?",
"Shops do not want to include the sales tax in the prices they announce. This is so that the products look cheaper then they are. People who have decided to buy a product after seeing the price tag is less inclined to change their minds when they get the final price at the checkout, if they even notice the sales tax at all. So by not including the sales tax in the price tag the stores increase their sales. The more politically correct argument is that a lot of chain stores use common marketing material across all shops in the chain which includes the price. Altering the marketing material for each legislation would cause some complications. Especially for television and Internet advertisements that may not be able to have custom advertisements for each tax legislation region.",
"I think the taxes are different in different states. That's why the taxes are not included in the price of product."
],
"score": [
10,
7,
3
],
"text_urls": [
[],
[],
[]
]
}
|
[
"url"
] |
[
"url"
] |
|
j22hy2
|
What’s the difference between reincarnation and rebirth?
|
Other
|
explainlikeimfive
|
{
"a_id": [
"g72vs7z"
],
"text": [
"Rebirth is thought of as a sort of spiritual renewal that happens during one's lifetime, typically when converting to, or reaffirming faith in, a religion (e.g. Born-again Christians). My understanding is that this is mostly symbolic, and will often be followed by the traditional induction into the faith usually applied to babies or children, such as a baptism. Reincarnation is the idea that the soul, after death, will transfer to a new being; either as a new person, or a different animal entirely."
],
"score": [
4
],
"text_urls": [
[]
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|
[
"url"
] |
[
"url"
] |
|
j22zig
|
How do places like the NYSE trading floor work? How do they get anything when all you ever see is people shouting at each other?
|
Other
|
explainlikeimfive
|
{
"a_id": [
"g72x0rq",
"g737j4v"
],
"text": [
"Modern stock trading is done almost exclusively by bots. The NYSE floor is a leftover from a bygone era. Even when stock trading was actually done on the NYSE floor it was not generally as frantic as movies portray it to have been.",
"If you go to the actual NYSE today, the space is all taken up by servers and desks for people to sit at their computers. The most action you see on the main floor area is tour groups, not traders doing anything."
],
"score": [
11,
6
],
"text_urls": [
[],
[]
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|
[
"url"
] |
[
"url"
] |
|
j23bb6
|
Why did so many animated shows during the early to mid 2000's have exactly 13 episodes per episodes per season?
|
i mean what's so special about about the number 13?
|
Other
|
explainlikeimfive
|
{
"a_id": [
"g72xvuj",
"g732tj3"
],
"text": [
"13 episodes a season was seen as ideal, because after 4 seasons you will have 52 episodes, enough to show one episode a week for an entire year. So 13 and 26 episode seasons, being 1/4 and 1/2 of the weeks in a year are common.",
"This is basically a standard in the TV industry, not just for animated series, but also for non-animated series. It was based on a TV \"season\" that ran from September to April or May, combined with how making episodes fit into a production schedule. Producers found that 26 episodes worked to fit into this pattern, back in the 1960s. Sometimes, when networks ordered a series to be produced, they would purchase a full season of 26 episodes, and sometimes they would purchase only a half of a season, which was 13 episodes. They'd choose the 13 episodes to produce if it was a mid-season replacement (starting January rather than September) or if they didn't have the budget for a full 26, or if they didn't feel confident enough about the show to do 26, and wanted to see how the early episodes did before committing the budget to 26. Then as production values went up over the decades, particularly in the 1990s, it became more difficult to do 26 episodes in the allotted time so this gradually shortened until 22 episodes per season became the norm. But the half seasons just stayed at 13 episodes. So ordering 13 episodes of a given animated show fit this pattern of 13 episodes being a standard low episode order to see how a show did before making a larger commitment."
],
"score": [
24,
5
],
"text_urls": [
[],
[]
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|
[
"url"
] |
[
"url"
] |
j23o7l
|
why does a rotating wheel or propeller spinning at high speed look like its spinning the other way sometimes?
|
Other
|
explainlikeimfive
|
{
"a_id": [
"g730i2y"
],
"text": [
"That is usually seen on recorded images, and it is because the rotation rate of the blade, is different to the frame rate of the film. So each new image has the blade in a new position, often near the last recorded image, but rarely the same, so the image appears to show a slow, sometimes reversed rotation. When in fact it is moving a great distance between images."
],
"score": [
4
],
"text_urls": [
[]
]
}
|
[
"url"
] |
[
"url"
] |
|
j25jtc
|
Why does it feel different to be under a warm blanket in a cold room than it does to just be in a warm room?
|
Physics
|
explainlikeimfive
|
{
"a_id": [
"g73dql1",
"g73brcr"
],
"text": [
"I'm thinking it might have to do with cold air on skin and cool air breathed in while the rest of the body is warm under the covers. So, the contrast in temperature is what feels so good? Edit: The body controls temperature through sweating (warm blood inside sent to the skin to cool). Under the covers the skin is warm with cool breathing brings cooling to the inside without moving blood. Maybe the body temp control system is operated differently and that's refreshing. Just thinking out loud.",
"Because the blanket holds the warm air (warmed by your own body) directly at your skin or at least very near to you. In the warm room the temperature must be at least body temperature to feel equally warm. Also, the feeling of a blanket on your body is calming to most people."
],
"score": [
5,
4
],
"text_urls": [
[],
[]
]
}
|
[
"url"
] |
[
"url"
] |
|
j25n88
|
How come meat on grocery store shelves are okay until the sell-by date, which can be 10-14 days away but refrigerated meat is said to go bad in 2-3 days?
|
Other
|
explainlikeimfive
|
{
"a_id": [
"g73gwfm",
"g73si6e"
],
"text": [
"Meat sold on shelves should also be refrigerated, so I have to assume you mean stuff you’ve already cook, that has then been refrigerated afterward, yes? If there’s somewhere selling unrefrigerated meat on shelves, you have a whole bunch of other more pressing issues.",
"A lot of assumptions and opinions. It’s entirely different. If you the consumer can ensure proper transport from store to home there is no three days. Follow the Best Buy date or better yet vacuum seal once it hits your home and your fine. Cooking it however changes the molecular structure. Virtually stripping the meat of the ammonia they wash meat in or whatever wet brine has been removed due to heating. Your now left with cooked meat which decomposes differently and at different rates compared to raw. FDA guidelines are exactly that guidelines. If you have a steak that you cooked at 2:00PM and only get to putting it in the fridge at 8:00. Your going to get diarrhea. It’s trash. If you have a steak that you cooked at 2:00PM and you put it in the fridge recently quick after eating. Apply the three day suggestion."
],
"score": [
5,
3
],
"text_urls": [
[],
[]
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|
[
"url"
] |
[
"url"
] |
|
j25qj3
|
Why do software updates (such as notable examples iTunes and iOS) now download the entire software every time, rather than just a small patch for the portion updated?
|
I miss the days of software patches. The program might be 5 gb, but the update patch might be just a fraction of that, and it would apply itself to the installed files. Nowadays it seems more common (or at least increasingly) that the provider just makes you download the entire program in the latest version. So ELI5: why is this done? It seems like a massive waste of bandwidth.
|
Technology
|
explainlikeimfive
|
{
"a_id": [
"g73gu3u",
"g73es40",
"g73z33l"
],
"text": [
"There are two issues with patches. Either you need a patch from every old version to the current version and every time you release and update to need to regenerate all these patches. Or you just create a patch from the previous version to the next version. If the user is out of date by several versions, then they need to download several patches and apply them all in order. Neither is particularly difficult, it's just one more thing to manage. Bandwidth is fast and cheap now, so it's just easier to make the user download the whole thing again.",
"> It seems like a massive waste of bandwidth. Because bandwidth and size are relatively negligible things these days. If a download is 5 gigs, what does it matter, that'll only take a few minutes to download on most modern broadband that people have. But if you have to write software that does patches in bits and pieces that will increase the installation times, and greatly increase the complexity of the software itself.",
"for iOS and Mac apps, the entire app bundle is cryptographically signed, so that it's easy to verify that the app has not been tampered with. This increases security and protects against malware, but also makes it difficult to release patches every time Apple releases a new version of XCode - even a small delta change - I have to download the entire 6+ GB file to install it"
],
"score": [
9,
7,
3
],
"text_urls": [
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|
[
"url"
] |
[
"url"
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j25qjn
|
How do they film nuclear blasts showcasing the wreckage on a fake town & retrieve the footage?
|
Other
|
explainlikeimfive
|
{
"a_id": [
"g74cnjl"
],
"text": [
"For those particular shots, they used both interior (inside the houses) and exterior (outside the houses) footage. The exterior cameras were on steel towers that would stand above the dust, anchored in a lot of cement. They were heavily shielded so that the radiation did not fog the film, and used very small cameras with very wide angle lenses, very close to the houses being destroyed. If your only goal is to make basically a pole that can survive a nuclear attack, you can do this — a nuclear blast will not destroy _everything_ at that distance (it tends to destroy things that humans live in, but not necessarily bunkers and steel and things specially constructed to survive the amount of blast and heat). The interior cameras could not be as shielded from radiation so they used radiation-insensitive films. They had some shielding but it was assumed that if the house got destroyed they'd just pick through the wreckage to find the camera. Presumably they put it in some kind of steel box or something so it would have a high chance of survival. In terms of retrieving the footage, the radiation from a nuclear explosion drops pretty quickly. This can be monitored of course with radiation detectors. Once it was safe to go get the footage, they went and got the footage. Nothing special about that. [This report]( URL_0 ) describes the camera setup used in these kinds of tests."
],
"score": [
3
],
"text_urls": [
[
"https://apps.dtic.mil/sti/pdfs/ADA995330.pdf"
]
]
}
|
[
"url"
] |
[
"url"
] |
|
j25rhq
|
How does it make sense to intentionally tank your resort businesses in order to avoid paying taxes?
|
Let's say I'm a struggling, but very well off, businessman in the resort and hospitality industry. I have golf resorts around the world, but all of them are losing millions of dollars every year, such that it almost seems intentional. On the bright side, I don't have to pay much (or anything) in taxes, since I'm losing money every year. Why not run a profitable resort? Is the tax penalty for running a successful business really that much worse than the millions of dollars in losses? How am I enriching myself here? Am I actually just laundering money? How does this stuff work? **Edit:** Ok, this is making a lot more sense after just a few responses. Followup question, what kind of criminal charges might be brought against me, if it turns out I am actually lying about my business's profitability and, my tax liability, and have been doing so for years?
|
Economics
|
explainlikeimfive
|
{
"a_id": [
"g73e0w6",
"g73eaby"
],
"text": [
"*Why not run a profitable resort?* Because that's actually *hard* to do. It takes skill, courage and the willingness to risk it all. *How am I enriching myself here?* Because you're **lying** about how much you're making. Example: Let's say the rich businessman employs a family member. Say it's his daughter. But his daughter also runs a totally separate consulting business. The rich man pays his daughter a fee for \"consulting\" on his project. This fee is tax deductible. But remember, his daughter works for *both* companies. To do this, he will literally take money *out* of one of his daughter's bank accounts and put it in *another* of his daughter's bank accounts, and then claim he \"lost\" the money because it was paid as a \"fee.\" And his tax bill went down. And there's nothing stopping the daughter from giving the money back to her father -- possibly in the form of another \"fee\" paid *to* the rich person from the \"consulting business.\" And then the daughter will claim *that* as a tax deductible expense. Lather, rinse, repeat.",
"I think we need to be clear that there is a difference between running an unprofitable business and making it LOOK like you are running an unprofitable business. Does it make sense to intentionally run an unprofitable business? No. Does it make sense to make it LOOK like you run an unprofitable business? Oh yes, absolutely. The tax savings are tremendous. Now, its terribly immoral and unpatriotic, but...certain people...certainly have the capacity to run such a scheme."
],
"score": [
9,
6
],
"text_urls": [
[],
[]
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|
[
"url"
] |
[
"url"
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j2600k
|
How does eating less result in less body fat and cause your veins to “pop out”
|
Currently cutting weight and curious how this works, also how/why is cardio so important during this process?
|
Biology
|
explainlikeimfive
|
{
"a_id": [
"g73fmh3",
"g73f8z2"
],
"text": [
"Fat is stored energy. When you eat less you’re consuming less energy. Your body makes up for this “lost” energy by using your fat stores. When your body fat gets low enough, your veins start to become more visible. Think of a lake with a submerged log. In this analogy the log is your vein and the lake is the body fat. The log has always been there, but as the water levels (your fat) go down, the log (your veins) become more visible. Cardio just helps you lose weight faster by stimulating muscle and burning additional energy.",
"Your body needs a certain amount of energy (calories) to run itself, plus more to do any activities. On any given day this may or may not match the calories you actually eat, so your body has a couple of ways to buffer energy (stored sugar, stored fat). Stored sugar can be used quickly, stored fat more slowly, but if your calorie intake is lower than your body needs for more than a short time, your body will start using the fat to fuel you. That's why eating less causes fat loss, your body is \"eating\" the fat to make up for the energy you're not eating with your mouth. Cardio isn't actually that important purely for the weight loss process, although it helps by driving up your calorie requirements. Fat burn is, to first order, just going to be the difference between what you ate and what you burned. Anything that drives the burn up will accelerate fat burn. There are lots of other very important health reasons that cardio is important though, so don't not do it."
],
"score": [
9,
4
],
"text_urls": [
[],
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|
[
"url"
] |
[
"url"
] |
j266ni
|
How does the Mandela effect work?
|
Psychology
|
explainlikeimfive
|
{
"a_id": [
"g73gi1s",
"g73h2e4"
],
"text": [
"As far as the likelihood of certain things being affected, I’m not quite sure. As far as to why it happens though, it’s because memory is a fickle thing, frequently prone to failure. Additionally, there are cultural misconceptions that can help spread it to a wide group of people. The origin of the name is of course referring to the South African leader Nelson Mandela, who many believed to have died in prison sometime in the 1980s. This was simply not true and someone started catalogue instances of things like that. A common pop culture instance would be “Luke, I am your father.” from Star Wars. Lots of people think that’s the line, when in reality, it is “No, I AM your father.” in response to Luke saying Vader killed his father. This is similar to why eye witness testimony is often not really reliable. We are really bad at remembering things perfectly accurately, and even worse, are really prone to outside suggestion, leading us to trick ourselves into “remembering” things that are untrue or inaccurate. There are tons of really small things you can likely attribute it to, that I am actually fairly certain I know why it happened though. A lot of this stuff would be what you’d describe as “Old Wives’ Tales” sort of things. Stuff that has been told through generations to help keep people safe or in line that has been like that for SO long, people don’t realize it is inaccurate. Taking band-aids off cuts so they can “Breathe” is a personal one in my family. I’m not really sure why my mom thinks that, but as far as I am aware, it gets all the oxygen it needs from blood flow. However there could be arguments on either side. Keeping it on traps moisture for things to grow, but also keeps debris out for instance.",
"The Mandela Effect is not a real thing. It's just a name we give to instances of common misremembering by the general public. Do you remember the Berenstain Bears books? Yes? Well, you and lots of other people think that they remember it being spelled \"Berenstein\". The fact of the matter is that you remember it that way because you just always assumed it when you heard the title, and glossed over reading it. And so did everyone else. And everyone is wrong because of it. It's always been spelled Berenstain. It's just people not paying close enough attention to details and then reinforcing each others bad memories."
],
"score": [
5,
3
],
"text_urls": [
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}
|
[
"url"
] |
[
"url"
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|
j26xrr
|
Why does rubbing/cleaning your belly button produce a lasting uncomfortable feeling there and your brain?
|
Biology
|
explainlikeimfive
|
{
"a_id": [
"g73pt61"
],
"text": [
"I'd like to know more. This is not something that happens to me when I clean my belly button. Ever."
],
"score": [
4
],
"text_urls": [
[]
]
}
|
[
"url"
] |
[
"url"
] |
|
j26yib
|
Why do people often shake their head when they're listening to music?
|
Other
|
explainlikeimfive
|
{
"a_id": [
"g73l4x1"
],
"text": [
"Internal metronome Essentially the brain is keeping timing by following along with the body. Also makes the person feel more engaged to the song"
],
"score": [
5
],
"text_urls": [
[]
]
}
|
[
"url"
] |
[
"url"
] |
|
j2717r
|
Why are sweet fruits so inconsistent in quality?
|
Biology
|
explainlikeimfive
|
{
"a_id": [
"g73un7e",
"g73nkst"
],
"text": [
"Sugars often take a longer time to form in a plant meaning it is important to let them ripen properly. Unfortunatley the realities of distribution and fruit spoilage means that fruits are picked early or stored in coolrooms for large periods of time before reaching us. This can have a large impact on flavour and texture. There would certainly be other factors too. Its hard to completley standardise nature.",
"things that grow on trees and bushes are harder to detect faults in over root and other ground foods. basically, you look at a carrot that's all mushy on the inside, you're gonna see it right away. you look at an apple all mushy inside, the only way to tell is to bite into it because the skin is hiding what the \"meat\" looks like"
],
"score": [
7,
4
],
"text_urls": [
[],
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|
[
"url"
] |
[
"url"
] |
|
j271u3
|
why are we taught to eat until we’re full instead of eating until we’re satisfied?
|
Other
|
explainlikeimfive
|
{
"a_id": [
"g73nbl7",
"g73ow3r",
"g73xu8y",
"g73mt91"
],
"text": [
"Our instincts don't line up with our current reality. Lots of people are hardwired to eat all the food they can stuff in because in nature you never know where your next meal is going to come from. We also have a number of cultural biases that you don't want to waste food, or that not cleaning your plate is rude, etc which are leftover from times when we didn't have a supermarket around the corner. For us in the Western world you never have to worry about your next meal, it's just a drive through away. So people eat far too much and get fat. It takes a fair amount of discipline to control your eating habits and make sure you calorie count etc, and that can be difficult even for professional athletes to keep under control. Obviously there's a lot more to the obesity epidemic than just that, but it's one factor.",
"If you live in the US, you had an entire generation of people who didn't have enough food to eat. Between the Great Depression, and food rationing during WWII, a lot of people grew up hungry. When the economy recovered after the War, they made sure their kids were never hungry. Their kids, meanwhile, grew up in a culture of \"clean your plate\". They taught that to their kids, who passed it down to theirs. Only in the last couple decades, with obesity becoming a hot topic, have parents started to slow down on the making their kids eat all their food thing. That, and a lot of people who grow up poor may prioritize making sure their kids have plenty of food over pretty much anything else. Hungry kids are a sign of failure for a lot of people.",
"I don't know how you are classifying eating until you are full versus eating until you are satisfied. Like others have stated, the biggest issue is to \"finish your food\" rather than eating until your body tells you to stop. Eating until you are over full is a bad idea, but eating until you are full isn't necessarily a bad thing. If you stop eating too early, and you end up hungry an hour after your meal you are more likely to snack, and people tend to eat worse when they are snacking than when they sit down to a full meal.",
"There was a study linked recently that explained why this is bad. I can try to find it. But it’s because we don’t want to waste, whether that be food or the financial toll your parents/guardians have to buy us food. It can also be a sign of disrespect if you don’t eat a lot of what someone cooked, at least in my experiences. Edit: kind of this URL_0"
],
"score": [
20,
11,
5,
3
],
"text_urls": [
[],
[],
[],
[
"https://www.google.com/amp/s/www.dailymail.co.uk/femail/article-2549590/amp/Forcing-child-clean-plate-cause-obese-later-life.html"
]
]
}
|
[
"url"
] |
[
"url"
] |
|
j274fe
|
Why can't we feel the earth rotating ?
|
Physics
|
explainlikeimfive
|
{
"a_id": [
"g73nbgs",
"g73m7pa",
"g73nnxt"
],
"text": [
"The Earth is very large. So even though it's rotating at a thousand miles an hour at the equator if you think of it as linear velocity It takes an entire day to go around once. If you were on a merry-go-round that went around once a day you wouldn't feel it rotating either. So it's very big but it moves at the speed of a clock, and not a normal clock but a 24-hour clock instead of a 12-hour clock. Technically you weigh ever so slightly less at the equator than you do at the North Pole because of ~~centripetal~~ centrifugal force. but because the Earth is so huge the total angle you change in direction is so tiny that it's less than a percent difference. Finally the Earth's movement is very smooth and continuous. if you're in an airplane you don't feel like you're moving 500 miles an hour because the airplane is moving 500 miles an hour continuously. The car you don't feel like you're doing 60 unless you're turning or going over bumps or something. I mean you do feel it when the car speeds up and slows down but the Earth doesn't do that. So the Earth never changes direction, and the Earth never changes velocity, and your sensation of movement is based entirely on changes in direction and velocity It's not impossible for an organism to feel these forces in theory, but in practice any organism that evolved to feel the motion of the Earth would go crazy. Such a sense would do you no good. EDIT: and before the pea dance descend, you on the surface of the Earth undergo a continuous change in velocity as the Earth rotates, abet a tiny and slow one. The earth itself does not undergo a change in velocity. It's angular momentum is conserved and it's total velocity as annular consistency. And for simplicity's sake I am ignoring the continuous change in direction caused by the motion of the earth around the sun, and the motion of the sun around the galaxy center. All-motion being relative, some vectors are unimportant in some discussions.",
"Because it is rotating at a constant rate. You cannot feel speed, only acceleration, and the Earths rotation is not changing and you are not accelerating, so you feel nothing.",
"Because the centrifugal force from the rotation is quite small and constant for a single location. On the equator where is largest, it is only 0.3% of gravity and on the poles the force it zero. It and the difference in earth radius that change gravity have a measurable effect because the weight differs by 0.5% between the poles and equator. In any location in between it changes the direction of down slightly. A human would not feel the difference if your travel between the equator and poles but even a cheap precision scale would detect it. the centrifugal force is the same as if you drive a car in a circle with 50 meters (164 feet) radius and each lap takes 4 minutes. So the forces from the rotation is quite a small constant ins strange and direction so it is is like a slight change in gravity."
],
"score": [
5,
4,
3
],
"text_urls": [
[],
[],
[]
]
}
|
[
"url"
] |
[
"url"
] |
|
j27i50
|
Is an 1100 lumen LED bulb on 73% brightness equal to an 800 lumen bulb on 100%?
|
If not, what would it be and why?
|
Technology
|
explainlikeimfive
|
{
"a_id": [
"g745mpa"
],
"text": [
"I would say, by definition, if the 1100 lumen bulb is outputting 800 lumens, then it is *set* to ~73.5% **brightness**. Theoretically, if you are setting brightness, you are adjusting the light level, not necessarily the power coming in. Thus, you're not concerned with the linearity."
],
"score": [
3
],
"text_urls": [
[]
]
}
|
[
"url"
] |
[
"url"
] |
j27jkn
|
why when something is very clean, it can be “squeaky” clean? Why is it squeaky?
|
A bit weird but I’m a house cleaner and I’ve wondered this for the longest time. Thanks in advance if anyone knows!
|
Chemistry
|
explainlikeimfive
|
{
"a_id": [
"g73tbzc"
],
"text": [
"The phrase dates back to the 1930s when hair shampoo that was much more harsh and less moisturizing than shampoos are today. That shampoo effectively stripped all the natural oils out of the hair, and when it was completely rinsed the hair would actually make squeaking sounds when rubbed between the fingers. This was erroneously thought to be an indication that the hair was appropriately clean, and in advertisements and high school health and hygiene classes, people were encouraged to wash and rinse until they achieved the “squeaky clean” result. Shampoos today are better balanced, and it’s understood that the natural oils are important and shouldn’t ever be stripped, but the phenomenon can still be experienced by people with normal or dry hair if they erroneously use a shampoo for oily hair."
],
"score": [
9
],
"text_urls": [
[]
]
}
|
[
"url"
] |
[
"url"
] |
j27jsj
|
How come blowing fire makes the flame stronger but blowing candles makes it die?
|
I actually wanna know because fires at camps and stuff grow when you blow\* but blowing at a candle puts it out. Imagine it's the same size as a campfire, so you can't just say because it's small.
|
Chemistry
|
explainlikeimfive
|
{
"a_id": [
"g73pwq2",
"g73sq4p",
"g73wg4h"
],
"text": [
"To make a fire you need three things; fuel, oxygen, heat or ignition source. When you blow out a candle you are cooling it off, thus the paraffin vapors don't ignite. When you blow on a campfire, you're adding extra oxygen.",
"It is just because it's small. When you blow air at a candle, the air you are blowing is much colder than the candle's flame. Because the candle is small, it doesn't take much cold air to make it too cool to continue burning. A little bit of cold air isn't enough to cool down a much bigger campfire, so it doesn't go out. So, it stays hot, and benefits from the extra oxygen it gets from the incoming air, and burns hotter. If you have a very small campfire, like just a single twig with the tip on fire, the flame goes out if you blow on it.",
"Some of the answers here are right, but one thing not mentioned. When you blow on a campfire, you're likely blowing the flame, heat, air and fuel TOWARD other fuel. You're making one part cooler but another part hotter. When you blow on a candle ... it's just the wick. Nothing else is there to benefit from getting additional flame, heat and fuel. If the wick cools down, there's nothing else there to support the fire reaction."
],
"score": [
19,
7,
6
],
"text_urls": [
[],
[],
[]
]
}
|
[
"url"
] |
[
"url"
] |
j27mw3
|
If you bump a part of your body do microbes fall off?
|
Just wanna know what happens to those little guys hanging out on my skin.
|
Biology
|
explainlikeimfive
|
{
"a_id": [
"g73vwqd"
],
"text": [
"One is generally wearing clothing, so I imagine the transference will probably happen between your skin and clothing. But yes, there will be a partial transference of anything on your skin; dead skin cells, oils, sweat, dust, and yes some bacteria. Its like bumping/pressing your forehead against a glass pain, a lot of what's on you will stick to it, easier to see too. But unfortunately a lot of them little guys will lose a home. One of my favourite factoids from biology, \" you're made up of more foreign cells that what are biological your own...\"! Heard it around a lot, sincerely hope its true. Hope this helps"
],
"score": [
19
],
"text_urls": [
[]
]
}
|
[
"url"
] |
[
"url"
] |
j27uyv
|
What is GitHub?
|
Technology
|
explainlikeimfive
|
{
"a_id": [
"g73s98d",
"g73scuc",
"g743fjo",
"g73v7rs"
],
"text": [
"It's a place where people can share code. A repository holds the code and GitHub let's people create many repositories.",
"So it is a place for people to share their work and be able to keep control of different versions of their work. The work is usually code. You can also share your work with lots of people and then control what edits people make to it.",
"**GitHub** is a part of Git which was made by Linus Torvalds(creator of Linux kernel). He wanted to create a collaborative platform to share projects. Most programs I use today came from GitHub. **Fun fact**: Linus wanted to create both Linux and Git for his personal use, but when he shared it, people liked the idea and started joining. **Why use GitHub**: Because it's open source and free. You can make your own projects like an app, a browser extension, a simple computer tool etc. and make the code publicly available to let others download and suggest you changes. Most tech companies mandate you to link your GitHub profile (which contains your project) with your resume. Also, since its open source and the code can be seen by everyone means that it's safe. Programmers may show off their work and skills by linking their GitHub profiles as boost about their projects openly. **What is a GitHub repository**: Repository is an English word which means storage. Your code(project) goes into a storage where you can store your data(code). But why even bring the concept of repositories? To make money. If you want to keep your project private (hide from public) i.e. your own private storage (private repository) then you need to pay a monthly subscription.",
"Let's start with the term \"Source Control\" or \"Version Control\". When you write a computer program you're constantly making changes to the source code files. Once you save those changes, you can't easily go back in case your new changes broke something. Source Control is a tool that lets you save different versions so if you mess something up, you can go back to an older version. A second very important part of this is more often than not, programmers work in teams. You and Me may work on the same file of source code on the same day. You add features, I fix a bug and add a different feature. Trying to manage that manually is nearly impossible. Modern source control tools can determine what lines changed in two different files and \"merge\" them together so both programmer's efforts are changed. It's not perfect but works well enough that it really helps a team work together better. One of the most popular source control tools is the open-source tool \"git\". GitHub is an online tool that uses \"git\" under the hood and provides a web-based interface to the \"git\" toolset. Now \"Repository\" or \"Repo\". For you to be able to work on the same project I'm working on, we both have to store our source code in a common location. It's not unusual to have many different projects. These projects are known as \"Repositories\" or \"repo\" for short. If you want to work on the same project I'm using, you will \"check out\" or \"clone\" the repo so that you have a local working copy. The server holds the main version. I check it out. We make our edits locally using the text editor or IDE of our choice. You could work in one tool, I could work in the other since the result is just a text file. Then when done with your edits and you're happy to share them back with the team you will check the changes back in with a \"commit\" action followed by a push of all your changed files back to the server. The next time I want to work on the project, I'll pull down all the changes made since I last worked on it and I end up with the latest code. One of the things that makes GitHub special is that many people like to work on open-source projects, even if they are the only one maintaining it. By posting your code to a public repository anyone else can download it and use it. They can always clone the latest version to get the updates to the project. They can also make changes and send them back for you look at and decide if you want to add their changes to your code. Hope this helps."
],
"score": [
6,
5,
4,
4
],
"text_urls": [
[],
[],
[],
[]
]
}
|
[
"url"
] |
[
"url"
] |
|
j282qq
|
Why do men sometimes see two streams of pee coming out when there's just one hole?
|
Biology
|
explainlikeimfive
|
{
"a_id": [
"g73tpms"
],
"text": [
"Ever squeeze a hose without a metal end? Pinching the middle makes 2 holes on the outside. Something keeps the center of the hole closed (“dried” fluids from intercourse or masturbation) and allows the urine to pass on either side. As a guy I do not once remember experiencing this if it’s happened to me, but find it incredible possible. Maybe there’s a better explanation out there, if so go nuts Reddit."
],
"score": [
4
],
"text_urls": [
[]
]
}
|
[
"url"
] |
[
"url"
] |
|
j28ewu
|
- what is the point of the wounded warrior project (USA) they have TV commercials asking for donations to help veterans who were injured in combat. Shouldn’t the military/government/insurance/some government organization be helping these poor soldiers?
|
Economics
|
explainlikeimfive
|
{
"a_id": [
"g73vjxk",
"g73xj3h",
"g7429rq"
],
"text": [
"the government does. but only to a minimum amount. not exactly \"enough\" to give them a \"good quality of life\". any public support the government provides, is a minimum amount of support, it'll keep you alive, yes. but not exactly provide a good quality of life.",
"If you want to know about the quality of are the VA provides allow me to tell you my one and only experience: I went to register and was told someone would get me shortly. 45 minutes later, after I found him,, the attendant said they lost track of me.... I was the only one there.",
"Wounded warrior *supposedly* supplements the government’s support where it is slow and lacking, but they barely offer a fraction of donations to veterans."
],
"score": [
26,
7,
4
],
"text_urls": [
[],
[],
[]
]
}
|
[
"url"
] |
[
"url"
] |
|
j28i7d
|
How come they still haven’t come up with a proper on demand subscription-based movie solution yet, along the lines of Spotify?
|
Other
|
explainlikeimfive
|
{
"a_id": [
"g73zahn",
"g73xxpx"
],
"text": [
"I think people are misunderstanding your question. Here's some info that may help. The music industry is very different than Hollywood in terms of \"ownership\". There are 6 major movie studios. They make most of the movies and own all the little studios too. They retain the rights to nearly everything that they make. So the intellectual property of Toy Story belongs to Disney, not the director, writer, or actors. Music is different. There are still major music labels. But there are a lot of small ones. But more importantly, music artists retain some of the ownership since it's their songwriting and recording. Musicians share ownership of their stuff with the labels. I believe this difference in ownership may contribute to why there isn't a single movie streaming platform. Each movie studio wants to make money directly with their movies. If the music industry did that, it would be too divided and the whole thing would flop.",
"My bad, I could have been a lot clearer. What I meant was, pretty much every song ever recorded is available on demand on Spotify. Why can’t the same be said of ever movie and TV programme?"
],
"score": [
4,
3
],
"text_urls": [
[],
[]
]
}
|
[
"url"
] |
[
"url"
] |
|
j28nnf
|
Do children actually have more energy than adults?
|
Biology
|
explainlikeimfive
|
{
"a_id": [
"g73y27q"
],
"text": [
"Very generally in the physics and biological sense, probably not. But kids do tend to have more enthusiasm and less ability to self monitor. So they will sometimes engage in something to the point of exhaustion. Kids (especially very young) quite commonly take short naps to recover (which they do rather quickly!) So overall they sometimes do appear like bundles of unending energy."
],
"score": [
5
],
"text_urls": [
[]
]
}
|
[
"url"
] |
[
"url"
] |
|
j28s16
|
How come cement gets dry on both cold and hot temperatures asap?
|
Chemistry
|
explainlikeimfive
|
{
"a_id": [
"g73yp3i",
"g73yzch"
],
"text": [
"Because it’s not “drying”, it’s setting. Concrete doesn’t harden by water evaporating, it hardens by the water causing the cement to form crystals that bond everything together. If you’re pouring concrete on a hot, dry day you need to cover it with plastic so it doesn’t dry out before setting. And you can’t pour it in cold winter times because the water will freeze before the concrete sets.",
"Because concrete does not “dry” Concrete “sets” What is going on is the water is actually chemically reacting with the cement mixture, not drying out of it. The speed of this chemical reaction is actually effected by temperature, concrete on average takes longer to set when it is colder out, (and if it’s gets below freezing any water that hadn’t reacted yet turns to ice, ruining the concrete, which is why concrete isn’t poured in winter)"
],
"score": [
13,
5
],
"text_urls": [
[],
[]
]
}
|
[
"url"
] |
[
"url"
] |
|
j28ya9
|
How do we know that particles are entangled and not just behaving the way they are because of random chance?
|
I’ve sifted through results explaining what entanglement is and I kind of understand what it means, but I can’t find a satisfying answer to this question.
|
Physics
|
explainlikeimfive
|
{
"a_id": [
"g73z5gk"
],
"text": [
"I you flip 2 coins and one lands heads and the other lands tails, do you think they are connected or dependent on each other in some way? No. It happens all the time. What if you do it again, and it happens again? Seems pretty normal still. It can happen. What about 3 times in a row? 4 times? Starts getting suspicious... How about 5000 times in a row, landing opposite of each other? How likely do you think it is now that they are dependent on each other? Do you think this is random chance? Could be. What do you think?"
],
"score": [
3
],
"text_urls": [
[]
]
}
|
[
"url"
] |
[
"url"
] |
j29ag2
|
How did pilots discover or who discovered ways for pilots to properly handle G-Force? For example the breathing techniques.
|
Biology
|
explainlikeimfive
|
{
"a_id": [
"g741omy",
"g745b9h",
"g7464xh"
],
"text": [
"I have no first-hand knowledge, but the reason for fainting under G forces is pretty easily determined -- drop in blood pressure to the brain (assuming the blood is properly oxygenated). All you would need is a blood pressure cuff to determine that. Then the next question is, well, what *increases* blood pressure to the brain, and can a pilot do that in the cockpit? And then it's trial-and-error.",
"They have giant centrifuges that they put teat subjects into, and then spin them to produce g-forces to measure the effects and to test equipment. It's basically a long rod, with a test capsule or cockpit mockup at the end.",
"Lots of experimentation. Pilots and other subjects strapped into [centrifuges]( URL_1 ) while wired for vital sign readings for testing different techniques and equipment to help survive high G-forces. [Rocket sleds]( URL_2 ) were also used a lot to determine the effects of acceleration and deceleration on pilots. Fun fact; Centrifuges [are still used]( URL_0 ) to train pilots on high G-Force coping techniques."
],
"score": [
5,
3,
3
],
"text_urls": [
[],
[],
[
"https://youtu.be/xJyBIUNlY2M",
"https://medicine.utoronto.ca/sites/default/files/humancentrifuge.jpg",
"https://youtu.be/omtISQp5bKg"
]
]
}
|
[
"url"
] |
[
"url"
] |
|
j29g73
|
Why does the sleepiness sometimes "go away" if you don't sleep as soon as you feel tired?
|
Biology
|
explainlikeimfive
|
{
"a_id": [
"g742i2a"
],
"text": [
"Because your brain is programmed to assume that if you’re staying awake and being active beyond when you’re supposed to that there must be an emergency. It’s a fight-or-flight response."
],
"score": [
9
],
"text_urls": [
[]
]
}
|
[
"url"
] |
[
"url"
] |
|
j29hq7
|
Why apple cider generally costs more than apple juice, even though it is supposedly less refined
|
EDIT: Sorry for the confusion -I wasn't referring to hard cider, as many people assumed. Let's take alcohol out of the mix for this one, though the cost of hard vs non-alcohilic would be a interesting conversation to have separately.
|
Economics
|
explainlikeimfive
|
{
"a_id": [
"g7429yh",
"g74amg5"
],
"text": [
"Apple juice has a much longer shelf life, so manufacturers generally don't have to worry about it spoiling. They can process it in gargantuan quantities whenever apples are cheap and store it until the market wants it. Apple cider goes bad more quickly, the manufacturer has to be more careful about when to process it and how to sell it, and may not be able to sell it before it goes bad. They also can't process at the same volumes because they need to stay \"closer\" to their market, or else pay more in transportation to move it further faster. And, most importantly...we're willing to pay more for cider than juice, so they charge more.",
"Because it is processed less it spoils much faster. That spoiling means they have to keep smaller stocks and it is produced in smaller batches which increases costs."
],
"score": [
27,
6
],
"text_urls": [
[],
[]
]
}
|
[
"url"
] |
[
"url"
] |
j29nlm
|
At night my voice goes a lot croakier and deeper and then returns to normal the moment i drink water. Why is this?
|
Biology
|
explainlikeimfive
|
{
"a_id": [
"g747q5g"
],
"text": [
"At night or when you lay down? If it's when you lay down, it could be post nasal drip that's settling in your throat instead of continuing down to your stomach (or getting coughed into your mouth). It could also be heartburn/acid reflux/GERD. Look into 'silent heartburn'."
],
"score": [
3
],
"text_urls": [
[]
]
}
|
[
"url"
] |
[
"url"
] |
|
j29te7
|
What exactly 'noir' and 'neo-noir' meant in films/books?
|
What do they mean? What I found is they are some fancy name for mystery/thriller stories happening in past. Means, I haven't seen a neo-noir film that's of romantic genre. So what exactly does this work mean?
|
Other
|
explainlikeimfive
|
{
"a_id": [
"g74a5zo"
],
"text": [
"*I haven't seen a neo-noir film that's of romantic genre.* Oh, I bet you've seen many, many of them, but not all of them would've been described that way. [Here's a list of ones from the last 10 years.]( URL_0 ) Enjoy. John Wick, The Dark Knight Rises and Inception are all on this list. I'm not sure I'd call them neo-noir, and perhaps not romances. But they're still being made, and Wikipedia editors seem to agree on this list, so..."
],
"score": [
3
],
"text_urls": [
[
"https://en.wikipedia.org/wiki/List_of_neo-noir_films#List_of_films:_2010–2019"
]
]
}
|
[
"url"
] |
[
"url"
] |
j2aaab
|
What is cloud computing and why is becoming more popular?
|
Technology
|
explainlikeimfive
|
{
"a_id": [
"g747388"
],
"text": [
"Cloud computing is simply storing data on a shared server that you don’t physically own. Instead of having a server at your company hold your business files, you pay Microsoft money to do it. On one hand it’s often more cost effective and there’s less risk of destroying data if damage or theft on an office or personal location happens. But there is always a risk of data loss or theft as someone else is holding onto your data for you."
],
"score": [
4
],
"text_urls": [
[]
]
}
|
[
"url"
] |
[
"url"
] |
|
j2azxd
|
When your favorite teacher yells at you and you try not to cry, why does your throat "do that thing"?
|
Biology
|
explainlikeimfive
|
{
"a_id": [
"g74ft2j"
],
"text": [
"That lump in your throat that you get when you try and force down the tears of shame is the result of muscle tension. It’s how our nervous system deals with stress! To combat stress, we breathe faster, which expands our glottis. When we try to swallow, the glottis is forced to close, and pushes the muscles that opened the glottis when we cry. This is referred to as the globus sensation. For more context, the glottis is a little flap of skin in your throat that keeps you from breathing in food and swallowing air (when it works properly)."
],
"score": [
14
],
"text_urls": [
[]
]
}
|
[
"url"
] |
[
"url"
] |
|
j2bies
|
How can there be different sizes of infinity sets if all of the sets are endless?
|
Maybe Eli4?
|
Mathematics
|
explainlikeimfive
|
{
"a_id": [
"g74fg05"
],
"text": [
"Imagine you wrote down every whole number starting from 1 and went on forever. That's an infinity. Now imagine you wrote down every whole *Even* number, starting at 2, then 4, then 6, etc. You can see that for every number in your second list, you can match it with a number in your first list just by dividing it by two. So 2 maps to 1 in the first list, 4 maps to 2 in the first list, 6 maps to 3 in the first list, and you can do this infinitely. This means that the second list is also infinite, but its the same size infinity as the first list. Now imagine you need to make a list of every decimal between 1 and 2. Where do you start? What's the first number in your list? 1.001? But that's bigger than 1.0001, which is bigger than 1.000000001. You can't find a starting point, and so you can't list the decimals all out, you can't count how many there are. This is also an infinity, but you can't link it to your first list. It is a \"bigger\" infinity than the first infinity."
],
"score": [
12
],
"text_urls": [
[]
]
}
|
[
"url"
] |
[
"url"
] |
j2bq64
|
what happens when you call a radio station?
|
Other
|
explainlikeimfive
|
{
"a_id": [
"g74g3cv"
],
"text": [
"When you call a radio station it's not like they put you directly on the air. A producer will answer the phone and ask how they can help you, and you can just tell them you'd like something played. They will say OK and that's the end of it. They aren't kidnapping you and putting you on the air against your will or anything like that."
],
"score": [
3
],
"text_urls": [
[]
]
}
|
[
"url"
] |
[
"url"
] |
|
j2brqi
|
How does a Software Update improve a Tesla's Acceleration/Top speed?
|
Technology
|
explainlikeimfive
|
{
"a_id": [
"g74guiq",
"g74h82t"
],
"text": [
"Acceleration, top speed and range are all somewhat determined by the amount of current being drawn from the batteries in the car. This amount is controlled by software and the hardware already on the vehicle. Tesla will, very likely, only allow initial settings that are fairly conservative until they have data that shows that the system can withstand higher current draws without reliability issues and long term damage. Once enough data is collected from enough vehicles, they might allow for less restrictive settings with more confidence that it will not have bad consequences. A software update can do this. In other words, the potential performance would already have been there all along, and it is just that the manufacturer did not want to risk it without sufficient data.",
"Battery temperature is the answer, more you demand from your battery hotter it gets. Tesla set their standards pretty high on 1st run, your battery reaches 70 F, it doesn't generate more power till it drops down to 65 F. Then they watched their cars, 10 million miles at 70F and no Tesla spontaneously combust, software update, push it to 75 F. Another 10 million miles at 75F and no spontaneous combustion, push the limit to throttle to 80F, and so on so forth."
],
"score": [
8,
3
],
"text_urls": [
[],
[]
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}
|
[
"url"
] |
[
"url"
] |
|
j2cgn4
|
Why does dancing around make it easier to hold in your pee?
|
Biology
|
explainlikeimfive
|
{
"a_id": [
"g74lfbb",
"g74p8zd",
"g751nwk"
],
"text": [
"You're focusing on something else. Just like when you're in an exciting movie alot of the time you won't realize how bad you need the bathroom until the movie is over.",
"Your body tightens those muscles in response. It’s not time to go yet. But if you relax too much, your body thinks it’s time to let go. That’s why when you get closer and closer to the toilet, it becomes more of an emergency. You start to relax those muscles in preparation",
"A distraction. I held my pee from a hour and a half road trip when I got my 1st tattoo. If I focused on not pissing myself, any pain I thought I would feel wouldn't be as bad."
],
"score": [
27,
14,
4
],
"text_urls": [
[],
[],
[]
]
}
|
[
"url"
] |
[
"url"
] |
|
j2ckux
|
Why do you get a headache when you have slept only a few hours the night before?
|
Biology
|
explainlikeimfive
|
{
"a_id": [
"g75oksl",
"g755uvl"
],
"text": [
"I don’t know that I understand it well enough to ELI5, but the brain filters cerebrospinal fluid CSF during sleep and it drains out of the ventricles of the brain. Less sleep = less time for drainage = a buildup of pressure and inflammation. I got these migraines daily since I never got enough sleep. A lot was related to a vitamin B2 deficiency. Vitamin B2 helps mitigate inflammation in the brain. Try taking a daily vitamin B complex supplement and see if that reduces the occurrences of the migraines.",
"There are 3 cycles/stages of sleep in humans. 1st cycle is just a normal phase where your body movements like breathing rate, heartbeat etcetera slows down to save energy for the next cycle cycle. In 2nd cycle lot of energy is consumed since crucial process like digestion, storing memory on brain etcetera take place. In the 3rd cycle aka Rem phase rapid eye movements takes place so that we can dream. If you wake in middle of any cycle then it will lead to headache. It doesn't matter if you sleep less but at least one cycle must be completed. In short if you woke in middle of any cycle then you will get headache and sleeping less is not the reason for your headache"
],
"score": [
44,
6
],
"text_urls": [
[],
[]
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}
|
[
"url"
] |
[
"url"
] |
|
j2cny6
|
why are wine glasses shaped the way they are instead of a normal glass cup?
|
Does it make it taste better or something?
|
Chemistry
|
explainlikeimfive
|
{
"a_id": [
"g74ns6z"
],
"text": [
"One reason why wine glasses are narrower at the top than the bottom is to concentrate the aroma (smell) of the wine as this is a major component in the experience of wine tasting. The wide bottom of the glass also helps increase oxygen exposure of the wine by increasing surface area. Oxygenating wine can help develop flavors and may help get rid off off flavors that can develop from the wine making process There are also different glasses for different types of wine. As a general rule I use stemmed glasses for white wines and stemless for reds. This is because white wines are typically served chilled so having a stem keeps your hands off of the glass thus preventing the heat from your hand from warming the wine. Red wines on the other hand are typically served at room temperature so keeping them cold is not an issue."
],
"score": [
10
],
"text_urls": [
[]
]
}
|
[
"url"
] |
[
"url"
] |
j2cpmq
|
Why is it a reaction to "shake off" our hands after we slam or jam our fingers?
|
Biology
|
explainlikeimfive
|
{
"a_id": [
"g74yot9",
"g74plb0"
],
"text": [
"One: Distraction - adding stimuli and movement helps to reduce the feeling of pain. Two: Protection - the cause of the pain isn't exactly understood by your brain, so it starts an immediate reaction to deal with it. Some painful stimuli (hot liquids, acids, biting insects) can be flung away. Three: Adrenaline - pain stimulates adrenaline, which gets your body wanting to move. Four: Blood flow - Injuries can cause blood to pool, shaking your hands will help with blood flow and stop some of the pooling which can cause secondary damage.",
"Like rubbing other injuries and other physical stimuli, creating other nerve impulses \"drowns out\" the pain signals on their way to the brain."
],
"score": [
354,
78
],
"text_urls": [
[],
[]
]
}
|
[
"url"
] |
[
"url"
] |
|
j2cwvr
|
How does a fat worm turn into a butterfly?
|
Biology
|
explainlikeimfive
|
{
"a_id": [
"g74ok7l",
"g74pcnj"
],
"text": [
"Worms do not turn into butterflies. Caterpillars do. But how they do it is a process I believe is called metamorphosis. There are some good youtube videos of how it looks. I suggest watching one. But essentially they convert their bodies from the caterpillar into a flying insect. It's pretty cool.",
"What ntengineer said is definitely true, but I think what goes on inside the cocoon is even cooler. I’m not sure if all butterflies do this, but at least some liquefy completely inside the cocoon as their cells move to completely different places and change purpose. It’s presented some challenges for researchers studying how the brain records memory, because butterflies somehow remember things from before, even though their brains disintegrate completely in between."
],
"score": [
6,
4
],
"text_urls": [
[],
[]
]
}
|
[
"url"
] |
[
"url"
] |
|
j2daen
|
What does “based” mean
|
Other
|
explainlikeimfive
|
{
"a_id": [
"g74uggt",
"g74sz9s"
],
"text": [
"It started out meaning cracked out, as in freebase cocaine. It was sort of reclaimed by a handful of rappers such as Lil B to mean unconcerned with the approval of others. In more recent times it came to mean unconcerned with political correctness or societal norms, and was quickly adopted by places like 4chan, Reddit and on discord to describe people who express racist or sexist views in public. However it spread out a lot and some people use it to just show approval of anything, hence memes like \"Based Monke\", accompanying pictures of apes. As with all such things, it means whatever the poster feels like in the moment, they may not even be aware of the meaning themselves. Redpilled was a term originally used a lot in incel spaces for people who had \"seen the truth\" that all women are shallow users of men and that they, the incels, would never find happiness through pursuit of sex or romance. It again warped on imageboards and social media, and now refers to someone who \"sees through\" the lies of liberal media and recognises the world for what it is (which can vary from a capitalist clown world, to a Jewish controlled globalist megastate, pizzgate conspiracy stuff, take your pick). It is also used widely as a general term of approval. E.g. \"Joe Rogan used to be based and redpilled, but he got woke and now he's a puppet of the liberal media.\" They're both pretty unpleasant terms but I imagine your friends are either using them innocently enough or trying to be edgy. Either way tell them that spouting 4chan memes in real life is cringey as hell.",
"It just conveys that something is agreeable to you, but is used in stupid contexts, from what I gather. Like “word” or “right on” but tongue in cheek instead of genuinely. So not actually agreeable to you in reality. I’m almost 30; I’m old so I don’t know shit. That’s just what I’ve gleaned for myself"
],
"score": [
15,
3
],
"text_urls": [
[],
[]
]
}
|
[
"url"
] |
[
"url"
] |
|
j2dy2d
|
We have a lot of liquids in our bodies. Why can we never feel them sloshing around?
|
Biology
|
explainlikeimfive
|
{
"a_id": [
"g74wx5m",
"g74ztm3",
"g751f9l",
"g75it0p",
"g753mtq",
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"g756yle",
"g75g01u",
"g75gskg",
"g755b76",
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],
"text": [
"Fill a water bottle all the way to the top so it’s pretty much spilling over and put the lid on, it might slosh a little bit it’s a lot harder to tell than if it’s half full. Your body doesn’t have much air mixed in with the liquids and your blood vessels have valves and can tighten to prevent blood from draining to other parts of your body when you move around.",
"Drink a pint of water in one go, then spin around on a swivel chair a few times, then quickly stop! ... and see if you can feel anything sloshing.",
"I mean to a degree you can. If you swallow a lot of air and water you can hear it slosh. That said most often you won’t be taking in enough air to have this effect and having air is very needed to hear sloshing. This is why urine can’t slosh inside you as there won’t ever be air inside the bladder. Same for the brain though the brain does have connective tissue as well. Fun fact when fighter pilots pull high G forced their blood can pool in their legs. This is kinds like you sloshing idea somewhat and is why fighter pilots pass out in maneuvers sometimes.",
"Wait... I can move my stomach and make it slosh around. It sounds like a water bed. Is there something wrong with me?",
"Feels like a good time to remind everyone - your bones are wet. (ELI5 answer, just to play by the rules: you don't feel it for a few reasons, depending where the fluid is. Some of it is because it's always there so you're used to it, others areas the space the fluid is in is completely full, so it doesnt \"slosh\". In other areas, bodies don't have the type of receptors that notice that kind of motion, and in still some others, like your stomach, as others have noted - you actually DO feel it sometimes. Your bones are always wet though...)",
"Watermelon contains a lot of water. It doesn’t slosh. If you soak a sponge it doesn’t slosh. High water content can mean something is saturated. Doesn’t mean it is still in a liquid state.",
"You don't have the same type of nerve endings in your stomach and intestines.There is a ton of stuff happening down there all the time and you simply don't have the ability to feel it (most of the time).",
"A lot of the time you do, but your brain tunes it out because its normal. Its like how you don't notice that you can see the tip of your nose, or the smell of your own home. I had a friend who had brain surgery, which among other things, allowed spinal fluid to get into a space it was never able to before. When she woke up she tilted her head and asked \"What's that sloshing feeling?\" Presumably we all feel that every day, we just ignore it.",
"If you try Psilocybin mushrooms you will feel all those liquids sloshing around. It’s pretty trippy!",
"Have you ever been on a roller coaster? That feeling you get in your stomach is the acid sloshing around.",
"Most of this liquid is on the inside of cells, locked inside the cell membranes, which act like a type of scaffold.",
"If you chug a whole bunch of liquid and then roll around, sometimes you’ll feel that sloshing. I know I’ve felt it after draining a couple bottles of water.",
"Once I got really sick. Stuff coming out both ends almost simultaneously. Went on for a qood while. I never felt emptier. Drank a half glass of water. I could literally feel and hear it in my guts sloshing around. Weird feeling. Would NOT recommend. P"
],
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3537,
762,
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3,
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|
[
"url"
] |
[
"url"
] |
|
j2e7n4
|
why didn’t Chris Wallace mute the mics so there’d be less interruptions?
|
Other
|
explainlikeimfive
|
{
"a_id": [
"g74zntx"
],
"text": [
"They have agreed upon rules for the debates and muting the mics was not included in those rules."
],
"score": [
19
],
"text_urls": [
[]
]
}
|
[
"url"
] |
[
"url"
] |
|
j2ekaw
|
Why it is hard to breathe when we are about to cry /or crying?
|
Biology
|
explainlikeimfive
|
{
"a_id": [
"g755web"
],
"text": [
"Both use your diaphragm. That's a single muscle that can physically only be doing one thing at a time. If it's doing crying motions it can't be doing the breathing motions. That's like \"why is it hard to knit when you're playing piano?\""
],
"score": [
13
],
"text_urls": [
[]
]
}
|
[
"url"
] |
[
"url"
] |
|
j2eyzy
|
Why do solar plants emit CO2?
|
URL_0 I was watching the video above and at around 6:42 the video explains how much less carbon a solar plant emits than a coal plant (45 gCO2eq/kWh versus 820 gCO2eq/kWh). I was wondering why a solar plant emits any carbon at all?
|
Earth Science
|
explainlikeimfive
|
{
"a_id": [
"g7530ne",
"g7532dg"
],
"text": [
"It almost definitely has to do with the manufacturing of solar panels. Precious metals are used in solar panels and the mining for these metals isn't exactly free. Still a great alternative",
"It is produced from materials mined and transported, then processed and turned into a solar panel, then delivered to where it needs to go and set up. The environmental impact of these steps could be reduced if we had cleaner electricity to manufacture them, and electric vehicles to transport them. But with our current infrastructure it’s far from zero impact."
],
"score": [
16,
7
],
"text_urls": [
[],
[]
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}
|
[
"url"
] |
[
"url"
] |
j2fhkf
|
what happens if someone drops to the ground while on a platform?
|
Excuse me if this is basic physics but I've been wondering about this for awhile. So more specifically, say someone is on some kind of platform and they're suspended in the air. The platform is dropped and they're falling to the ground. If the person were to stay standing on that platform and managed to jump up from the platform just before it hit the ground and then land on the platform after it hit the ground what would happen? Would the platform absorb all the impact of the drop and the person be okay? Would there be some kind of built up force on the person that would cause them to be injured? I feel like this could be somehow related to jumping in an elevator at the right moment and you get that weird feeling when you land just right, but I have no idea. ELI5!! Disclaimer: I will not test these theories in real life no matter how curious I am.
|
Physics
|
explainlikeimfive
|
{
"a_id": [
"g756jhc",
"g756bvf",
"g7579nn",
"g756p5o",
"g758782"
],
"text": [
"All you’re doing is accelerating the platform just before impact, and slightly reducing the speed at which you’re falling. It would be extremely slight however unless the drop was very small. In order for this to work you’d need to be able to spring off a falling super heavy platform. With a drop of a few feet you could probably get away with it and be fine. Higher though and you’re falling faster than you can overcome just by jumping. You can decrease your speed like you’re suggesting, but you’re still gonna hit the ground pretty hard.",
"Both the platform and the person will hit the ground in the same way. Hard and fast. If you're suggesting the person is bound to the platform in someway, it's weight simply adds to the persons weight when deciding how much energy it has gained from falling. If the person is separated from the platform but falling with it, he will have his own energy from falling but it will not be something he can overcome on his own. At the very best, either the platform or his own legs could crumple and spread the force of his fall out over a longer period of time to cause less injury.",
"I forgot this sub's mods hate smart jokes. I wanted to make a joke about the phrase \"Terminal velocity\" but jokes get deleted here. To answer your question: Basically you're still falling at a speed greater than your legs could possibly propel you upwards at. The force with which you hit the ground minus the force you propel yourself from the platform with would still probably be enough to kill you depending on the height of the platform.",
"The longer you fall, regardless of you're on a platform or in an elevator, the faster you fall, up to a certain maximum \"terminal velocity\". Jumping up will only slow you down as much as that your body is able to, which would be difficult as is on a falling platform. As an example, say that when you jump, you can generate enough energy to move 5km/h up. This is the same if you're moving down at 10km/h or 50km/h. Jumping will technically result in a slightly less harsh landing... But nearly impossible and marginally effective. Better brace yourself and get enough dampening material between you and the ground, that'll work way better.",
"There would be a small difference. If you can jump two feet while standing on solid ground, and the platform was dropped from 10 feet, it would be similar to falling from somewhere between 8 and 10 feet. Full calculation would depend on relative mass and air resistance."
],
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12,
5,
4,
4,
3
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"text_urls": [
[],
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|
[
"url"
] |
[
"url"
] |
j2fksh
|
Do sports teams that share a home stadium (MetLife Stadium, SoFi Stadium, etc) have separate home team locker rooms or do they just convert them before each game?
|
Other
|
explainlikeimfive
|
{
"a_id": [
"g757es5"
],
"text": [
"Most major stadiums have somewhere between 6 and 8 locker rooms. It allows them to easily be used for extra events without worry. This was actually a thing during the NHL playoffs this year. With 14 teams starting in each stadium, they had to use the same locker room for different teams. After the first couple rounds they finally got to go down to permanent rooms for each team."
],
"score": [
10
],
"text_urls": [
[]
]
}
|
[
"url"
] |
[
"url"
] |
|
j2g1rm
|
What is the difference between being asleep and being under anesthesia?
|
Biology
|
explainlikeimfive
|
{
"a_id": [
"g75a2z0",
"g75a66c"
],
"text": [
"You know how when you sleep you have dreams and even if you don't have any dreams (or don't remember them), when you wake up you still have a sense of having been a sleep for the last X hours. Being under anesthesia isn't like that. It's like blinking. Every time I've had it (twilight or general), they give you some meds through your IV and then you wake up in the recovery room. There's no in between.",
"Anesthesia is medically induced unconsciousness, so it's more like a coma than sleep. When you are asleep, a part of your brain is still conscious and will alarm you if they notice any signs of danger: a loud noise, someone touching you, someone causing you pain etc. When you're under anesthesia, you're out. You're out until the medication wears off. That's why anesthesiologists get paid A LOT, despite seemingly not doing much. They carry a lot of responsibility and need to be very knowledgeable in different anesthesia and their effects, all possible complications etc."
],
"score": [
9,
6
],
"text_urls": [
[],
[]
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}
|
[
"url"
] |
[
"url"
] |
|
j2gax5
|
Why do we sometimes hear random sounds in our head
|
It sounds so real that even sometimes match with you surrounding... so if you are in a tunnel the sound you will hear will echo...
|
Other
|
explainlikeimfive
|
{
"a_id": [
"g75kdup"
],
"text": [
"Your mind is doing a TON of things at once. Human brains have this dope structure in the middle of our brains that can pass info to the other side. It just really really sucks at it’s job sometimes and one part of your brain winds up “guessing” what the message is or it will make one up as best it can. When this happens your mind is filling in whatever info is not being passed properly"
],
"score": [
4
],
"text_urls": [
[]
]
}
|
[
"url"
] |
[
"url"
] |
j2gc7q
|
What exactly is a muscle knot? What causes them and why do massages relieve them?
|
[verwijderd]
|
Biology
|
explainlikeimfive
|
{
"a_id": [
"g75h8lg",
"g75flnm",
"g75jhn0",
"g75ezuc",
"g75px6q",
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"g76uzyj",
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],
"text": [
"Knots are actually caused by the fascia, basically a lining of fibers over all your muscles and organs etc. When you have a knot the fibers can get kinda bunched up on themselves, which is what you feel when you touch one. Massaging serves to relax and stretch out those bunches and flatten the fascia again, which also means it won't be pulling on your muscles in a funny way and will help your muscles feel better.",
"Why do I have permanent knots? Nothing helps (physio, heat, massage, muscle relaxants)",
"Muscles can change in many ways (lengthen, shorten, contract, relax, grow, atrophy) according to Davis' Law of Soft Tissue Adaption, which states that muscles change based on what happens to them. If you use a muscle too much, it can get \"stuck\" in a partially contracted state all the time and refuse to let go. Muscles are kind of weird as far as having knots versus the entire muscle. For instance, some muscles cross multiple joints and therefore have multiple actions (biceps crosses both the shoulder and elbow joint) and because of that, contracting across the shoulder and elbow will affect those different parts of the muscle differently. Knots happen when only a small part of the muscle gets stuck instead of the whole thing. Massage is a very specific and localized stretch for the muscle. By stretching the muscle (or knotty part of the muscle) long enough, the muscle adapts to the tension placed on it (Davis' Law) and stops contracting.",
"Basically a part of your muscle wants to contract really tight and won't relax and stretch back out. Massaging helps loosen it.",
"A knot often is a bunched up area but consider also that when it is bunched up the other end will be stretched thin. Often the massage therapist will work the other areas causing the bunched up area to unbunch.",
"A lot of comments in here suggest temporary remedies such as dry needling, cupping, massage therapy, and even chiropractors. These can be helpful in reliving your knots and pains, but don't address the root cause of your pain. Your posture AND your activation of muscular/fascia system to create tension. Your tension propels you forward through space and work together to lengthen your spine. I've only found effective remedies from a \"training\" method from Functional Patterns. They look at the body objectively and have began developing methods to relieve pain. I put \"training\" in quotations because it's not your typical pump iron, throw weight around, run cardio til you can't breathe. Some corrective exercises have you move inches while retensioning your muscles, bone, and fascia to properly realign and have structural integrity.",
"I'm sorry that this is not a \"like you're 5\" explanation, but this issue (like most things having to do with pain, injury, or physiology) is complicated and I can't give that simple of an explanation personally. But I'm seeing lots of people produce answers that are blatantly incorrect. Instead of going and asking them for evidence about fascia, or muscle tightness, or whatever this week's unproven explanation that's used as justification for unvalidated physical therapy interventions (like acupuncture, massage therapy, foam rolling, myofascial release etc. ), I thought I'd just provide an article that gives some insight into this issue from an expert. You may find his experience interesting, or it may be more than you care to read, which would be fair. Not everyone cares about this stuff as much as I do. But suffice it to say, the human body is very complicated and there is not always a clear physiological or biological explanation for phenomena that are influenced by psychology and environment. This is why the current research has embraced the \"Bio-psycho-social\" perspective on pain, and has all but abandoned a pure biomedical approach. Here's the article: URL_0 This website has lots of good articles about many things having to do with pain and injury. If you find yourself intrigued I'd recommend browsing it when you have a question about something in particular.",
"I'd recommend this video: [What are \"muscle knots\"? (for massage therapists and clients)]( URL_0 ) He says there's no such thing as a muscle knot and there's no corresponding medical term. He then goes on to describe things that might be called knots in common usage. 1. Tight postural muscles 2. Unidentified lumpy anatomy, like a big twangy tendon 3. Trigger points. Trigger point theory says that certain areas of your body can refer pain, which means you feel it elsewhere. But there is no medical research confirming the existence of trigger points with bundles of tightness or nodules, and when different massage therapists try to identify trigger point \"knots\" they often don't even select the same locations. (Note that it seems this is controversial and many people believe firmly in trigger point \"knots\" despite the available evidence. See [this]( URL_1 ) for more detail.)"
],
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"https://www.painscience.com/articles/trigger-point-doubts.php"
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[
"https://www.youtube.com/watch?v=NMhIw4yr5s8",
"https://www.painscience.com/articles/trigger-point-doubts.php"
]
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}
|
[
"url"
] |
[
"url"
] |
j2gdgi
|
Why does inbreeding cause children to have mutations?
|
Biology
|
explainlikeimfive
|
{
"a_id": [
"g75caz4",
"g75jaz6",
"g75cqzr"
],
"text": [
"Let say Person A has a bad gene that they could potentially pass on to an offspring. They meet person B, marry person B, but person B’s likelihood of passing on a bad version of that gene is slim to none. Person A and Person B get married, and their child doesn’t have that disease. Through chance, variation and probability they’ve dodged a bullet. Let’s say Person A reproduced with their sister, call the sister Person AA. Because they’re siblings, the likelihood of them carrying the same predisposition for the same bad genes are high. If you combine those those two similar genomes to create offspring you’ll realize there is a lack of variation which increases the probability of passing on those mutant genes to their child. TL;DR- inbred mutations stem from a lack of variation in a genome.",
"Think of the genes in your DNA like a huge page of text. That page generally has a scattering of holes in it - broken copies of genes that don't work properly. Luckily, you have a spare copy, one page from either parent. If you've got a hole in one page, you just read the text from the other, and you're fine. Of course, if those holes line up, you've got *zero* working copies of that gene, and you're shit out of luck. Whatever that gene did, you don't get. Luckily, this is really really rare; the chances of both pages having holes in the exact same place are minute. Unless... unless both pages come from very closely-related individuals - because the closer you're related, the more identical the pages, and the more those holes will be in the same places. And the more that happens, the more you are fucked.",
"Mutations are not caused by inbreeding. Mutations are just accidents that happen in your DNA and it's not caught by proofreaders. Now, the answer to the question I Think you're asking is that inbreeding increases the risk of two parents having a gene that is considered bad. If two people who are both carriers for a 'bad' gene have children, their child has ~25% of having two copies of the gene and having the 'mutation', as you called it. It more likely that both parents will be carriers if they come from the same family."
],
"score": [
19,
9,
3
],
"text_urls": [
[],
[],
[]
]
}
|
[
"url"
] |
[
"url"
] |
|
j2ggzg
|
Why do they put those packets of "lethal if consumed" things in stuff?
|
Example: I got some clothes delivered & they had a packet labeled, "BENTONITE: DO NOT EAT" inside of the bag, so why do they put packets of things like that in clothes (or any package, really), what purpose do they serve?
|
Chemistry
|
explainlikeimfive
|
{
"a_id": [
"g75bn24",
"g75bpps"
],
"text": [
"Usually it's Silica Gel and it's use to avoid humidity building up in your package/clothes/shoes. Basically it works by effecticely soaking up most of the humidity in the packaging",
"It's just silica desiccant; it's not LETHAL if you eat it. It's there to keep things dry while being shipped in case there's a leak in the packaging and it's humid out. It's just not edible so they make sure that idiots don't eat it: URL_0 It's no more lethal than eating some pillow stuffing."
],
"score": [
15,
8
],
"text_urls": [
[],
[
"https://en.wikipedia.org/wiki/Silica_gel"
]
]
}
|
[
"url"
] |
[
"url"
] |
j2gko3
|
Is there a major difference (less etymology, more sociopolitics) between ‘equity,’ ‘equality,’ and ‘parity,’ and what are the implications?
|
Other
|
explainlikeimfive
|
{
"a_id": [
"g75g036",
"g75o981"
],
"text": [
"I'm not going to try and say that \"equity means A and equality means B\", because I've seen a few of those and I don't think they're well supported by etymology or by common usage. (There's a slightly-famous one with three kids of different heights trying to see over a fence.) The basic distinction is something like this: imagine we have Population A, a million people who average $45,000 a year, and Population B, also a million people, who average $49,000 a year, and we've got four billion dollars to distribute. One way to be fair to both groups is to treat everyone the same because they're all human beings. 4 billion divided by 2 million = $2000 so we give that amount to each person, paying no attention to which population they're from. This takes A to $47,000 for the year, and B to $51,000. I'd call this something like 'equality of treatment'. Another approach is we could try to erase the difference between the populations. 4 billion divided by 1 million = $4000, so that's perfect. We give $4000 to each person in Population A, nothing to Population B, and when we're done everybody got $49,000 this year. This one, I believe, is called 'equality of outcome'. And, of course, you could do a mix where first you give money to the poorer population until they get to some cutoff ($46,000 or whatever) and after that's done, you divvy up the remaining money among all people. You can make a case for each of those as being the most 'fair', and each of those cases will infuriate some people. It's an interesting topic and I think the best answer will depend on particulars of the case.",
"[This image]( URL_0 ) illustrates the difference simply and well."
],
"score": [
5,
3
],
"text_urls": [
[],
[
"http://croftw.chem.utoronto.ca/wp/womeninchemto/wp-content/uploads/sites/17/2020/07/Equality-equity-justice-lores.png"
]
]
}
|
[
"url"
] |
[
"url"
] |
|
j2go5d
|
Why hasn't supply caught up with demand with regards to international air freight shipping delays?
|
We are told that pilots are losing their jobs as thousands of aircraft remain on the ground because there is no demand yet typical shipping times for air freight has increased by a factor of 3 since March 2020.
|
Economics
|
explainlikeimfive
|
{
"a_id": [
"g75dsyi",
"g75dfaz",
"g75efeb"
],
"text": [
"Because a lot of air cargo goes in the passenger plans in the cargo hold. No passenger planes means way less cargo delivered. There are far fewer cargo planes than passenger planes. The cost to change the the planes from passengers to cargo has not been worth the cost by many airlines.",
"Because air freight requires aircraft. Nobody is going to buy extra aircraft for a short term change in freight demand, even if the planes could be built and delivered quickly.",
"A lack of passenger flights means that cargo capacity from the spare luggage capacity has been cut back significantly. Jets are expensive and can't be produced instantly, so cargo airlines can't just start flying more jets to meet demand, and it's expensive and impractical to convert passenger jets to makeshift freighters. Also pilots are trained to specific types of aircraft, so even if you somehow had a bunch of one type of freighter aircraft laying around, chances are it would be difficult to find extra pilots that happen to be trained on that type of aircraft."
],
"score": [
8,
3,
3
],
"text_urls": [
[],
[],
[]
]
}
|
[
"url"
] |
[
"url"
] |
j2h03x
|
Why are most democratic elections relatively close to 50/50 and never a landslide victory for one party?
|
Other
|
explainlikeimfive
|
{
"a_id": [
"g75guxr",
"g75es61",
"g75fh8b"
],
"text": [
"That is not true. The 50/50 thing happens a lot in democratic system that have only two real parties. Of course those type of systems are bad systems and most democracies don't use anything like that and therefore have different outcomes. What happens if you only have two real choices is that both parties will try to compete for the voters in the middle. Each side tries to gain as many voters as they can without losing more voters in the process. With better voting systems you have parties and candidates that stand for certain things and get voted on based on those issues. In a two party winner takes it all system the choices morph to reflect what half the voters want. This is no hard and fast rule. Often the truth is somewhere in between and in some cases the whole thing breaks down like it currently seems to have in the US.",
"First, a close to 50/50 outcome only occurs in a two party system. If there was a 90/10 outcome, that would be more indicative of a one party system with a small portion party. There are plenty of elections that don't end up 50/50 in countries with many parties, but those aren't landslides either.",
"Politicians and political parties tries to adjust their political platform so they will still win but also do as much radical changes as they can get away with. This is because if an opponent can promise more changes but still win then voters will prefer them. It is a constant balancing act of being liked just enough by the opposite side to win the election but still be liked by your own side. And the optimal balance will give a 50/50 outcome of the election. Even in multi-party systems there is often a 50/50 split between the parties of the winning coalition and the losing coalition."
],
"score": [
8,
3,
3
],
"text_urls": [
[],
[],
[]
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}
|
[
"url"
] |
[
"url"
] |
|
j2h7ym
|
how winning in court is actually deserved with the lawyer/prosecutor system?
|
Other
|
explainlikeimfive
|
{
"a_id": [
"g75fyrr",
"g75g45u"
],
"text": [
"Criminal courts in many developed nations do not determine who is right, they determine if the state/crown has proved beyond reasonable doubt that a person is guilty of the crime. I don't know what you mean by deserved. Deserved implies satisfying some type of objective morality, but criminal courts are not designed for that purpose. It doesn't matter if the outcome of a case is deserved or not, only that it remains internally consistent with the rules we create for ourselves.",
"I'm a criminal defense attorney. The skill of lawyers matters a lot when it's a close call one way or the other, and a really bad lawyer can lose a case that should have been won even if it wasn't that close. But, when both attorneys are competent, their skill doesn't matter as much as the facts do. The best defense lawyers in the world lose cases against competent prosecutors all the time. Hernandez, Cosby, Weinstein, Stone, Manafort, all those guys had great lawyers and they all lost. Whitey Bulger had one of the best attorneys there is and he lost. When the prosecutor is competent and there's plenty of evidence, you're only going to win on a total fluke. Sometimes my clients are like \"let's take it to trial, I believe in you\" because I won their last trial, or because I won three trials in a row over the last two months, or whatever else, and I have to tell them \"I don't believe I can beat video of you doing it, two independent witnesses, and the incriminating statements you made,\" and I can't. No one can. So, long story short, I can win close calls that worse attorneys can't. I can beat a stupid prosecutor or a lazy prosecutor.or a lazy, stupid prosecutor even if it shouldn't have been a close call. But, when there's plenty of evidence, no realistic way to get it excluded or suppressed, and the prosecutor is competent, the facts matter a whole hell of a lot more than your attorney."
],
"score": [
8,
8
],
"text_urls": [
[],
[]
]
}
|
[
"url"
] |
[
"url"
] |
|
j2hh6n
|
What is the brain “deciding” when it goes into a coma?
|
Basically, what is the brain doing when it goes “okay, we’re gonna go into a coma?” Sorry if this is vague.
|
Biology
|
explainlikeimfive
|
{
"a_id": [
"g75h4du",
"g75qf90"
],
"text": [
"Lets say you drop your phone and it stops working. The phone didn't decide to break. Something happened to it that made it unable to do what it is supposed to. The same idea applies to our brains. If part of our brain is injured or otherwise incapable of doing what it supposed to happen, but not so injured that we die, we get a coma instead.",
"Firstly there is a really big question as to what the brain is doing when you are awake. How the brain moves from a conscious awake state into unconsciousness is something that a lot of neuroscientists are studying. Its also important to differentiate a 'coma' from other unconscious states like sleep. In general however the brain goes into coma when something - injury, or drugs like anaesthetics, or illness - disrupts the ability to maintain the sorts of activity that we think of as awake consciousness. This could be because a large part of the brain is affected or because one or more of the much smaller deep structures in the brain that are very important for maintaining an awake state are affected. People wake up from coma's because whatever was causing that disruption has now been removed and activity can carry on as normal. This might be because the body has recovered from an injury enough or because the aneasthetic drug has been cleared. If the damage is severe enough it may be permanent in which case the brain is never able to return to normal function and will remain in a coma indefinitely. This is very different from sleep in which although the brain is not 'awake' there is still important ongoing structured activity happening."
],
"score": [
18,
4
],
"text_urls": [
[],
[]
]
}
|
[
"url"
] |
[
"url"
] |
j2hilc
|
Why can’t robots tick a box to get through a recaptcha test?
|
Technology
|
explainlikeimfive
|
{
"a_id": [
"g75hood",
"g75jvqt",
"g75kn2h",
"g75k2um",
"g75kuqm"
],
"text": [
"The point there is not clicking the box. It's about how you click the box. A robot will do it perfectly, a perfect straight line, in less than a second, without doubts, without having to correct the mouse movement. You have to click it moving the mouse, so you'll need to think about how you are doing it, losing some time, then move the mouse but your hand will never do a perfect straight line. You'll also probably need to correct the trajectory and move it slower near the end because neither the mouse, the table or your hand are perfect mechanical systems. Edit: [According to this]( URL_1 ) Google knows how you interact with the captcha even after clicking on it. Probably even knows how you interacted with past captchas?. The algorithm seems like a secret, but probably based on IA. They can even know if the mobile device has detected a tactile response so they know it's not a bot with touchscreens. Edit 2: [Here you can found another response with an interesting vid]( URL_0 )",
"The not a robot check is usually served to the more reliable people. Reliability is based on items such as IP address (a unique identifier for your current internet session), your internet provider, history within similar IP addresses, and more. Once it's shown, this challenge usually relies on user input and data such as mouse pointer movement, or detecting a touch event if on mobile). Suspicious IPs usually encounter the image challenges. Google uses user input to build its AI for detecting stop signs, bikes, etc.. When Google can't reliably identify these yet with 100% accuracy, most bot makers don't stand a chance.",
"It's not the box. Behind the box is an AI that tries to guess if you're a robot. If it thinks you're a robot, you get a normal CAPTCHA (e.g. \"click the traffic lights\"). So it's no use.",
"Most of the times it doesn't really matter if you're a bot or not. It's repeated interactions that are a problem, and in those cases the button turns into a proper captcha",
"Real check is not how you click captcha. Scripts run in the background that fingerprints you and verifies that the browser and the activity is normal. If you have privacy oriented configuration like things to block fingerprinting, recaptcha will annoy you to hell by repeatedly asking to identity objects even after you do it right. Mouse interaction can be faked as you asked as reply to another comment. Also, it'll set cookies once you complete a captcha a the ticking process is just it verifying that this is a normal browser with normal human browsing activity."
],
"score": [
133,
18,
6,
5,
5
],
"text_urls": [
[
"https://www.reddit.com/r/explainlikeimfive/comments/j2hilc/eli5_why_cant_robots_tick_a_box_to_get_through_a/g75jf8r?utm_source=share&utm_medium=web2x&context=3",
"https://security.googleblog.com/2014/12/are-you-robot-introducing-no-captcha.html"
],
[],
[],
[],
[]
]
}
|
[
"url"
] |
[
"url"
] |
|
j2hmnd
|
When you say a word over and over why does it start sounding like a fake word? Like unrealistic mumbjo jumbo mixing of random letters?
|
Other
|
explainlikeimfive
|
{
"a_id": [
"g75kk44",
"g75jqok"
],
"text": [
"This is called semantic satiation ( URL_0 ). Basically you build up a tolerance to the word triggering the normal parts of your brain because you've triggered them so much. It goes back to normal eventually.",
"Your brain is good at ignoring repetitive stimuli and doing things without thinking after practice. You’re literally tuning yourself out"
],
"score": [
28,
3
],
"text_urls": [
[
"https://en.m.wikipedia.org/wiki/Semantic_satiation"
],
[]
]
}
|
[
"url"
] |
[
"url"
] |
|
j2hn48
|
What are Stocks
|
Economics
|
explainlikeimfive
|
{
"a_id": [
"g75i6lq",
"g75iis5"
],
"text": [
"> What are they? Stocks are, in essence, equal portions of a company. When you buy a stock, you're buying a part of that company. If a company has 1,000,000 shares in existence and you buy 1 share, you own 1/1,000,000 of the company. Usually shares come with rights, such as voting rights, as well as the right to receive dividends, which are payments made to people who owns shares from the company. > Also, how do you invest in something that’s not yours? Well, once you buy shares, they are yours. It's exactly the same as when you buy something at the store. Once you buy it, you own it. > Why are they so valuable? If a company is really successful, it'll make a lot of money. This means the value of the company will go up because people will be willing to pay lots of money for shares in that company. Not all shares are valuable, though. They can go up and down in value. > What are stock brokers and traders? Stock brokers are the people who buy the shares on your behalf. You give them a call, ask them to buy X number of shares in XYZ company, and they do it for you in return for a small fee. The nature of brokers, however, is rapidly changing. Stock traders are people who buy and sell shares. Some buy them with a view to sell them soon afterwards for a profit, while others buy them and then hold onto them for years, maybe decades. > Is it easier to get into them then you think? I have no idea how easy you think it is, and am therefore unable to answer this question.",
"Stocks are a little piece of (figurative) paper that says that you own a (very) small share of the company that issued it. They sold this to you so they can use that money to invest back in to the company and continue to grow. They, in turn, are responsible for making decisions (by law) that are in the interests of the stockholders. They can't just sell you the stock and then spend it all on gummy bears and chocolate milk. They will do things that hopefully will make that stock you bought worth more as the services they provide become more desirable or they expand their share of whatever industry they are in. Now to answer the specific questions. > Why are they so valuable? A lot of them aren't. You'll hear lots of news about Amazon and Tesla and Nvidia going from a smaller price per share to crazy prices over a small time. If you bought one share of telsa in like 2011 for $35. It's now worth over $400. Selling it today would make you $365 for doing nothing but holding on to the stock. For every one you hear about, there are thousands that stay the same price year over year or decline. Some go out of business and you lose all the money you bought the stocks for. The value is over time, the average price of all stocks in a particular index (aggregate of companies listed) tend to increase 7% per year. This is where compound interest comes in. If on year one you have $1000 in an index fund (a bunch of stocks from various companies across variations industries), on year two, the average of those will be $1070. Year 3 you will have (on average) $1144. After 20 years it'll be over $4000. 300% more than your initial investment. This is what people mean by \"putting your money to work\". You didn't lift a finger but you made money. This is with out adding any additional contributions. You want to invest early and don't touch it until you retire. The more you add the faster it grows. This is another reason you'll hear \"it takes money to make money\". And \"Turing $100 into $110 is work. Turing $10 million into $11 million is inevitable\". It's slow progress at first, but it gets way easier later on > What are stock brokers Basically middlemen that connect companies selling stocks and people wanting to buy them. They take a percentage of the transactions for their services. > Is it easy to get into Yup. If you are young and have the forethought to start saving for retirement, you can open an Individual Retirement Account (IRA) and toss your extra money in there. There are lots of rules surrounding these accounts, but the gist is just toss your extra money in there and forget about it into you're 67. Your future self will thank you. Remember the compound interest thing. I might suggest one of those \"robo\" advisor services that auto diversify the funds to have the best luck at growing over time, like Betterment. I'm sure you can look them and their competitors up easily enough. They don't take as much for their fee because the work is done by computers instead of people, so their cost of doing business is lower. A \"normal\" management fee would 2% (which eats in to the targeted 7% you want). The robo ones can be 0.25% or lower Others ways are that most big companies that you may get a job at have retirement plans through them (401k). You can take money you earn and before you pay taxes on that money, you can put it in the 401k tax free. You really can't avoid the taxman forever, so you'll pay taxes on the money you take out of this fund when you retire. Now this is the most financially sound way of getting in to stocks. There's a whole other world of \"day trading\" where you buy and sell stocks daily. Hoping that you are buying it for a low number and selling it for a high number. There's even more beyond that with options, puts, calls, derivatives, etc (the stuff that goes on in /r/wallstreetbets)... But from what I gather it's not much better than gambling (it's right there in the name of the subreddit)"
],
"score": [
53,
5
],
"text_urls": [
[],
[]
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}
|
[
"url"
] |
[
"url"
] |
|
j2hn7g
|
why do most cameras have higher framerates in low light, but lower framerates in bright lights?
|
Other
|
explainlikeimfive
|
{
"a_id": [
"g75l7ol",
"g75iasf"
],
"text": [
"Its actually the other way around. Bright lights allow you to use higher framerates as you can have shorter exposure times. /u/precision1998 comment is correct.",
"There's a minimum amount of light that needs to reach the camera sensor for you to be able to see the image. Now, when it gets darker, there are multiple methods of increasing image brightness: A. Increase the sensor's light sensitivity This is commonly known as \"ISO\", and you've probably seen that setting before. The issue with just raising ISO ever higher is, that the image will become more grainy. This is like if you turn a Vinyl player's volume to 1%, but crank the speakers to 100%. You will be able to hear the music, but there will also be a lot of noise and humming from your Amp. B. Increase the aperture size The aperture is like a mechanical iris that controls how much light falls onto the sensor. The more open it is the more light reaches the sensor. This would be your go-to setting on something like a DSLR camera, because it does not affect the grainyness. The issue with smartphone cameras for example is, that there's only so much space available in the camera module, and you can't really change your aperture all that much. So in extreme low light conditions, this is compensated by A or C. C. **Increase the exposure time** So to reach a sort of middle ground between *not-so-large-apertures* and *low-iso-means-low-noise*, you can also just wait for more light to reach the sensor per frame. This is what you are referring to. Because there's less light per unit of time hitting your sensor, it needs to compensate by \"developing\" the frames longer. That requires you to hold the camera more still than usual, because more exposure time per frame also means more time for you to make the image shaky."
],
"score": [
13,
3
],
"text_urls": [
[],
[]
]
}
|
[
"url"
] |
[
"url"
] |
|
j2hvc7
|
Is a psychopath created or natural?
|
Biology
|
explainlikeimfive
|
{
"a_id": [
"g75j30p",
"g75nedd",
"g75iuxm"
],
"text": [
"They can learn things and be influenced just like everybody else, but there are some pretty specific things that are different about their brains. When they do functional-MRI scans on psychopaths, the brain regions that handle empathy are mostly dark. Because of that, they're hard to teach. Arguments like \"hurting people is bad because they experience pain the same way you do\" don't resonate with a psychopath.",
"From what I understand psychopathy is the result of a birth defect whilst sociopathy is a result of conditioning. Both have similar symptoms, and show reduced connectivity to / activity in the amygdala (I think). Funnily enough addictions tend to cause the same form of brain damage.",
"Psychopathy is generally believed to form in very early childhood and even before birth. So it's likely a mix of genetic and epigenetic factors. Your upbringing doesn't matter much, at the time that starts the brain is already different from other people. (The part responsible for social learning is smaller) How exactly it manifests can possibly be influenced though."
],
"score": [
8,
6,
4
],
"text_urls": [
[],
[],
[]
]
}
|
[
"url"
] |
[
"url"
] |
|
j2imjb
|
Why isn't there a software that can reverse the blur of an image to get the original?
|
Title.
|
Technology
|
explainlikeimfive
|
{
"a_id": [
"g75my1q",
"g75mshw"
],
"text": [
"Digital images are made up of a bunch of numbers that the computer turns into colors on your monitor. When an image is scrambled, it is making unknown changes to those numbers. If you don't know what changes were made you'll never know what the original image was. For example, if I start with the number 163: 163, flip the digits 361, add 10 371, multiply by 2 742 If I just showed you the final number, 742, and asked what the original number was there no way you'd know it was 163.",
"You can to some degree. E.g. URL_0 You can’t do it perfectly because blurring loses information, which you can’t get back."
],
"score": [
12,
5
],
"text_urls": [
[],
[
"https://venturebeat.com/2020/01/22/researchers-use-ai-to-deblur-human-faces-in-photos/"
]
]
}
|
[
"url"
] |
[
"url"
] |
j2in9o
|
How do they create huge rectangular wooden planks from tree trunks when almost all tree trunks are circular?
|
I recently got some construction work done at home and noticed that the huge wooden planks used for making doors or other parts, could not be obtained from cutting any tree I have seen in my life from any angle. How do they make them?
|
Technology
|
explainlikeimfive
|
{
"a_id": [
"g75mia4",
"g75mgz1",
"g75n3wh",
"g75oacf"
],
"text": [
"There are patterns of horizontal and vertical cuts along a log which leave you with planks, beams and very little waste overall. The bigger the log the bigger the planks you can cut out of it- and then there's book-matching whereby you put two planks which have been cut vertically side by side ( ll ) flat next to each other ( _ _ )- sometimes if the grain is subtle and matches well enough it can be hard to tell that you have two \"book-matched\" pieces together and not one large flat piece. Also there are definitely trees six feet or more wide.",
"Draw a circle, now draw the biggest square you can inside it. Sometimes it's more complicated, you see charts of a log divvied up like a beef carcass.",
"Do you mean plywood? Usually the boards are 3/8inch to 3/4inch thick and 4ft by 8ft. Google image it if you're unsure. A plywood board is made of a bunch of thin sheets of wood glued together. It's like a stack of paper. Look at the edges of the plywood sheet and you'll see what I mean. They take a big log and turn/spin it in a machine and peel the outside layers of it into the thin sheets. [Like if you held a pencil in each hand and turned it using your teeth to grind it except these blades are calibrated to make very very fine even sheets]. Then they glue the sheets together till the board is between 3/8inch and 3/4inch thick. Then they sand then cut them into the 4ft by 8ft rectangles.",
"Boards are cut the long dimension of the tree trunk in a computerized saw mill . Before boards are cut often bark is stripped off and sold for landscaping projects. The logs are then turned on a type of lathe to make wood veneer for plywood and furniture. The remaining wood is cut into boards . Most of the sawdust is collected and pressed board of different types are made including large particle OSB sheeting for roofs and exterior walls , medium density particle board for floor underlayment and shelving. and fine particle MDF for furniture and mouldings ."
],
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14,
12,
7,
3
],
"text_urls": [
[],
[],
[],
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|
[
"url"
] |
[
"url"
] |
j2ineb
|
What is wrong with hover hands?
|
Other
|
explainlikeimfive
|
{
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"Nothing. Back in the early days it was mostly poking fun at guys who who got nervous taking pictures with girls and couldn't bring themselves to actually put their hand on a shoulder/waist. Now it is mostly a strategy to avoid sexual harassment charges..."
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6
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j2io8h
|
Why didn’t the first US presidential debate include muting of the candidate that wasn’t asked a question?
|
Other
|
explainlikeimfive
|
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"Because, in my opinion, this Presidential debate is not actually about political discourse. I would make the assertion that this is more akin to a sporting event: what happens and how the participants behave is less important than how many people are watching. If the candidates couldn't cut one another off, it would make for a less dramatic experience for the audience. High drama, particularly this year, is important -- on the whole it raises awareness and gets people who might not ordinarily care roped into a narrative, which, in turn, might get them out to the polls. Drama is particularly in the interest of Trump, his supporters speak no other language. So. While I agree that mic muting would likely be nice, in some form, my belief is that it cannot happen because this presidential debate is not actually about its content. It is about the drama and the narrative and the presentation. It's a performance, not a debate.",
"Usually they let each other speak so there would be no need to mute anyone. Please vote guys, this cannot become the new normal.",
"As far as I understand it, the campaigns agree to terms with each other and the stations. If the station or the other campaign demands something they don’t want to do they just won’t do the debate. So the stations adding a mic mute button could essentially lead to both campaigns not participating in the debate at all. After tonight we might have been better off without one, though.",
"Because we still hope, against hope, that the president can be presidential rather than act like a toddler?",
"Muting of a mic means the direct sound is lost BUT with the number of other mics nearby you could still hear something. What it could encourage is more shouting/yelling to get your answer heard and it also encourages partisan voters/fans to claim bias against their candidate for restricting speech - anything not clearly audible could be made up/twisted. It's better to hear everything and use facts to counter conjecture. I think everyone also hopes that a presidential candidate could act with decorum and the need to have a talking stick isn't necessary... buuuut, here we are.",
"> Is this a network decision or do the candidates have to agree to elements of the debate set up like this? Both, but the candidates have the most leverage for conditions of the debate. There's a strong incentive for networks to not be too picky. > should really be what the process is for it to be changed for the second debate? It would be a join negotiation between the network hosting it, and the two campaigns. I doubt the networks are willing to try to fight for it. They're fairly agnostic as long as it still brings in views.",
"Do you have examples of US presidential debate where a candidate got his mic muted while he talks when his time is up ? Would they notice if their mic is muted (they don't have a device to hear themselves, do they ?) ? I don't think anyone thought it would be needed. Minimal standards of manners were expected.",
"Because it's likely the one of the candidates wouldn't agree to the debate if they didn't explicitly agree to disallow muting.",
"I was wondering that, myself. I'd support mute buttons for ALL debates, though it would mandate greater scrutiny in choice of moderators -- Basically, more like Wallace. I'm not saying he's perfect, but he's one of the better ones. Someone who was afraid to question one candidate but not the other, or someone who has some other form of clear bias, would absolutely abuse the privilege. Perhaps one partial solution would be to set it up so that giving control/speaking time to one candidate for X number of minutes would mute the other for exactly that amount of time, and then mute both as soon as the time ends; i.e., force them to stay within the time limits. The sad thing is, I'm fairly certain that, once Donny Boy realized he was being muted, he'd probably try to rush Biden and steal his mic or something else idiotic like that. He's used to being a bully, and I don't think he'd hesitate to do something that childish.",
"Because you shouldn't have to treat POTUS like a toddler. Apparently it is necessary though."
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j2ix1t
|
Why do we sometimes think of the worst scenario?
|
Like if I just turn left a little I’ll ruin my car and get in a bad accident. Edit: I’ve even heard of comedians speaking about this, like why does our brain sometimes tell us if we just lean over too far on a cliff what would happen.
|
Other
|
explainlikeimfive
|
{
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"text": [
"This is called the [call of the void]( URL_0 ). Check it out it is quite normal. We don't fully understand why it happens but your exact scenario was described in the article.",
"It's actually evolution thing. Imagine 40000 years ago You and Your Neanderthal friend were walking through a savannah and there was some movement in the grass. Your friend went \"Uhghg rabbit, me pet rabbit\". You on the other hand thought \"ughgh lion! Me run!\" So you ran, and it came out to be rabbit, so your friend played with it (probably ate it later) and everyone was fine. Next day same situation happened \"Ughgh rabbit\" vs \"Ughghgh lion\". And it was lion indeed, and it ate your friend.And you survived. You came back to your cave, went to sleep with the rest of the tribe. But there was some weird noise when you were sleeping, some of you thought it was just a wind, some of you thought it was a bear. And it was a bear, and it killed all the \"wind belivers\", while the rest ran for their lifes. and things like this were happening all the time, so in the end only people who assumed the worst survived, but with time (but not that long ago) there was fewer and fewer threats, but our brain was still programmed to assume the worst case scenario, and here we are in 2020 having the same mindset to assume the worst, in extreme scanerions (like mine, but i will get to that) it causes anxiety and depression. What's worth noticing is that some thought are automatic but they not always have to be real, like assuming the worst, or if i think that a pink elephant will walk into my room. Source: My Anxiety and Depression CBT"
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[
"https://www.healthline.com/health/call-of-the-void"
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|
[
"url"
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[
"url"
] |
j2jimj
|
Why does a phone screen "dim" out when exposed to sunlight but the screens of Game Boys and calculators brighten up when exposed to said sunlight?
|
Pretty dumb question aside, yes I know very well sunlight is much brighter than a phone screen even in its highest brightness setting, but what exactly is happening in **both** cases?
|
Technology
|
explainlikeimfive
|
{
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"text": [
"Screens of calculators have no internal lighting. You can see numbers because external light is reflected from the mirror layer of the screen. Screens of smartphones and computers have internal backlight and no reflective layer.",
"Most phones, game boys and calculators are using liquid crystal displays. They bend and filter light. On a phone, they have big white lamp behind the screen and shine light though. In calculators and game boys, they have a reflecty bit behind the screen that reflects the light. The sun is a lot brighter than the lamp in the phone, so it seems darker. But the sun reflects off the reflecty bit on the game boy/calculator, so it seems really bright."
],
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6,
4
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[
"url"
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[
"url"
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j2jx6p
|
- How does the body fall asleep / go into an unconscious state?
|
When we are trying to fall asleep, what suddenly happens to cause us to tap out for a few hours?
|
Biology
|
explainlikeimfive
|
{
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"text": [
"I hope I got your question right. There is no agreed upon definition of how people fall asleep exactly. However researchers know this for sure: When we are awake we get lots of different inputs (visuals, sound, taste, smell and touch) and our brains are processing these all the time. When we turn off the sound (or hear a monotonous/relaxing sound which doesn't give a lot of stimuli) and close our eyes the brain slowly starts shutting down. Imagine you are constanty stomping in a water puddle and by that you constantly produce lots of waves. Then you start stomping less hard and less frequent. Now we're in stage 1 of falling asleep. The brain produces so called \"alpha waves\" which means we are yet in a wake state but in deep relaxation. If you gradually stomp less hard and less frequent you enter stage 2: The brain mainly produces so called \"theta waves\" which means it already shut off all surroundings, but is interrupted by short bursts of activity (the alpha waves) which quickly cool down again. There's only little waves produced by wind and you frequently stomp a little again from time to time. Think of a time you dozed off while watching a movie: You remember bits and pieces of scenes before you finally fall asleep completely . These activity \"beats\" beat further and further apart until they completely stop. This is the moment we drift into Stages 3 and 4 (which is when we start Dreaming) - the deep wave phase. The surroundings are completely shut off. Now you've completely stopped giving it input and the only little waves produced are by the wind. The rest of the night we cycle between stages 2, 3 and 4. I hope this is not too confusing. Cheers!",
"In English, \"unconscious\" means two different things. It can either mean \"lacking conscious thought\" or \"lacking conscious thought and unable to be returned to conscious thought through stimulus.\" When we sleep not in REM sleep we lack conscious thought, but we can be returned to consciousness through stimulus. When we are unconscious due to drugs or trauma we cannot be returned to consciousness via stimulus. To put it simply, unconsciousness through trauma or drugs, the brain is \"off\" disconnected from stimulus and inactive. Unconsciousness through sleeping is more about the muscles being off and the brain in low power mode, with stimulus being able to switch it on. And the brain doesn't remain in unconscious mode while sleeping, as dreams (almost a fake consciousness) fill the mind periodically while we sleep. The neocortex, which controls high brain function, is quiet during non-rem sleep, called deep sleep or slow wave sleep with relatively low conscious brain activity. Studies have shown that interrupting this phase of sleep harms memory and learning consolidation. What quiets the neocortex to enter low conscious sleep mode? (Well the neocortex doesn't go completely quiet... It's patterns just change to be rhythmic while in deep sleep, while it is less rhythmic and more active during conscious wakefulness or \"conscious\" REM sleep.) Other neurons and chemical release, seem to put the neocortex into the rhythmic unconscious state. It should be noted that neurons and chemical release control almost all bodily functions so what matters are which neurons and which chemicals are released that put the mind to sleep. To understand that is to leave the ELI5 world and enter neural biology and chemistry: URL_0 But it's a specific combination. TLDR: Other parts of your brain signal the parts the brain that do conscious thought, via nerve signals and chemicals, to fire rhythmically in an \"unconscious\" pattern while you are in deep wave sleep.",
"Your body releases a chemical called melatonin to help you fall asleep. The chemical is produced in the brain(I think) and goes into the bloodstream. Not sure if it causes you to sleep, or helps to get to that point. Someone else can add to this."
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[
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j2kcwk
|
Why can’t a candidate be muted during a debate once it’s another candidate’s turn to speak?
|
Other
|
explainlikeimfive
|
{
"a_id": [
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"text": [
"Great question...I hope someone in the millions that watched America embarrass itself last night can answer.",
"Assuming here, but I don’t think they thought it would ACTUALLY be a necessity. It’ll be interesting to see if they implement anything new in the next debates since this one was a shitshow. I also think another reason they don’t do it is that I don’t see it being a deterrent. I feel like they’d still shout across the stage and we’d all be trying to read their lips. It would probably just cause more confusion. And my last thought would be that they want us to see the candidates as they are, so we can judge them for their behavior. And I’m hoping everyone is."
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|
j2kt3d
|
How do fitness trackers know that you actually sleeping but not just laying there resting, being awake ?
|
Edit: Thanks for all the answers and the awards, I’m shook
|
Technology
|
explainlikeimfive
|
{
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"text": [
"Your heart beats slows down when you sleep, they will use a mixture of heart rate and how long you haven't moved to determine how you've slept",
"> How do fitness trackers know that you actually sleeping They don't. They just estimate based on heart rate and movement. It can be pretty far off sometimes.",
"I work in a sleep lab, and honestly they're not as accurate as they make out. They give a good indication but they shouldn't be taken too seriously.",
"I’m not sure they actually do know. “Sleep” is more objectively determined by brain wave activity (it can be measured). Intuitively, I’d guess this is correlated with activity and HR to some degree, but I haven’t seen convincing evidence of this. I’ve switched tracker brands and had substantial differences in steps that are measured, so I’d speculate they’re only loosely accurate in sleep tracking. What’s probably more important is the day-to-day fluctuations.",
"Chronobiologist who studies sleep in a military population here: Most consumer sleep trackers use proprietary algorithms to determine sleep/wake using heart rate variability, activity (typically a piezoelectric accelerometer), user input (sleep marker), and a light sensor. We do not know if their algorithms are similar to what is used in medical/clinical sleep devices. For example Fitbit uses heart rate variability and activity recorded in epochs of 30 seconds. Raw unscored data is unavailable to consumers. For consumer purposes they are accurate enough, but I would advise against putting too much trust in \"sleep stages\", they typically do not hold up against PSG which is the gold standard. Clinically speaking, we do not use them. Our devices cost between $600-2,000, and the software requires training to score sleep (we score by hand after running through our algorithm).",
"They don’t. This is really just a gimmic. [This article in the New York Times]( URL_0 ) looked at this issue and found wild inaccuracies.",
"Also they they don’t. They can guess, but they don’t. I do rn know from heart rate, but just because your heart rate is up does not mean you’re exercising. Similarly, your heart rate being lower doesn’t mean you are asleep. My migraine app on my phone can’t distinguish between “laying on a table because user is not using phone right now” and “user is not using phone and therefore sleeping. They can guess, and ask us, and then use our responses as another piece of data to make better guesses, but they don’t “know”.",
"I need background noise to sleep. My tracker decided that I was awake all night because the tv was on. I slept like a rock. Next night I turned the tv off, slept really badly and my tracker was like, that’s better! Uninstalled, lol.",
"They don't, they just make educated guesses. When you sleep, you heartbeat slows down and your body is more still than when you are awake. Even if you do move around when sleeping, you will be in one set location while when you are awake, you are more likely to be moving around the area. So what they do is see how still you are, how far you have moved and how much your heartbeat has slowed down compared to your regular heartbeat. I quite often spend my evenings in bed just watching movies or YouTube videos. My tracker will estimate that I was sleeping from 8-9pm while in reality, I didn't actually go to sleep until midnight. But that's because I settle in and don't move much which also slows my heartbeat.",
"Mine tracks light/deep/REM sleep. About twice a week I pull all-nighters (insomnia) and my watch says I slept 9+ hours. What a liar.",
"My fitbit often doesn't know the difference. If I lie down and meditate, it will count it as a light sleep. Same with if I wake up but keep lying in bed. It will tell me I'm sleeping while I'm lying there scrolling through the app. I wonder if it's maybe because I have a low resting heart rate it's harder for it to tell? or do they do that for everyone?",
"Short answer: They don't. Shallow answer: They can tell the difference between active vs. inactive, but \"resting awake\" vs. \"asleep\" is gonna be a crap shoot. Generally they'll see a \"low activity\" block of time and then if it's long enough they call it \"sleep\". ELI20: They use a few things to try to guess - mostly motion sensors and heart rate - but they aren't actually very accurate. For very \"normal\" people they work, but not very many people are all that \"normal\". This is especially problematic because the people that are most interested in the data are usually people with disordered sleep - the same people the trackers have the most trouble with. Source: I worked on validating activity prediction algorithms for wrist-worn heart rate sensors for a number of years.",
"Isn't that what the two cameras are for?",
"They don't. Once my Fitbit registered a nap, but I was just being a lazy fuck laying in bed watching shows. I guess I didn't move for a really long time",
"They don't. Garmin, fitbit, apple, if I'm laying in bed at midnight scrolling through reddit threads until 2am, they have all shown me as falling asleep at midnight. Even with me hittin the backlight every 30 mins and look at the screen to see what time it is.",
"They don't. My samsung watch makes false sleep logs all the time when I read a book, meditate, watch a movie, etc.",
"It doesn't *know*, it makes an educated guess. If you somehow managed to lie as still as you do while sleeping for 7 hours, the fitness tracker would very likely assume you were sleeping. And so would a human observer too, probably.",
"When I wake up in the morning and lie in bed scrolling Reddit or talking to people for an hour, my Fitbit has no idea I'm awake. It monitors heartbeat. I honestly think movement is a big component as well as heart rate that others have mentioned",
"They're not 100% accurate. I heard that when monks wear them they only register as sleeping.",
"I don’t think they do. I was reading and it registered as sleep and when I thought I was asleep it said I was awake (I fidget really badly when I am asleep)",
"Some times they dont. I typically sit in bed and watch tv for a bit before i go to bed and my old fitbit always thought that i was asleep during this time so my sleep stats were always a little off",
"Many of them do not, depending on how you sleep. As someone who spends hours laying awake at night, if I am relatively still, it thinks I'm sleeping. For accurate sleep tracking, it requires more than simply heart rate and movement tracking.",
"As people have mentioned, these stats are just a guess. I knew most of these HR+Step+Sleep+Workout monitor watches were gimmicks. And after trying both a high end and medium end watches, Im convinced. Even the simple step counter gives incorrect measurements some days (but it's still good enough to get a rough estimates of how many steps you took overall)."
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j2l4t0
|
When something burns down and turns into ashes, it takes up significantly less space... where does all the stuff go?
|
I don't know if I am phrasing this to be understandable, but when you burn down something the resulting ash has a significant smaller volume than the object you burned. Why? Where does all the matter go?
|
Physics
|
explainlikeimfive
|
{
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"text": [
"The air. The carbon and hydrogen in the fuel combine with oxygen to create CO2 and H2O (water). These just go up in the air (CO2 is gas in room temperature, water from fire is still hot so it's steam). Other particles float away on the hot air as smoke.",
"[Photosynthesis]( URL_0 ) is when plants take 6 carbon dioxides and 6 water molecules, to form a sugar and release oxygen. The plants then chain together the sugar molecules to form [cellulose]( URL_1 ), which forms the trunk / body of the plant. So, by weight, a big tree that may weigh a few tons, those are tons of carbon dioxide and water that formed the body of that tree. When wood and other materials burn, the carbon atoms in them combine with oxygen from the air, to form carbon dioxide. And the hydrogen atoms combine with oxygen from the air to form water. The tons of weight from the tree that burned down, go back into the air. Also when you breathe, each cell in your body combines the sugars you eat from food, with the oxygen from the lungs, to form carbon dioxide and water. The carbon dioxide is transported by blood back to the lungs and exhaled, and the water is retained, used if necessary, and/or peed or sweated out if it's a surplus. All these atoms and molecules, carbon, hydrogen, oxygen, water, carbon dioxide, they get cycled around the Earth, basically, by people, animals, and plants."
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|
[
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[
"url"
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j2ljzx
|
Why are mouthwashes acidic when toothpastes are alkaline?
|
Chemistry
|
explainlikeimfive
|
{
"a_id": [
"g7659sa"
],
"text": [
"They have different functions. Toothpaste is there to mechanically remove plaque, so that bacteria has nowhere to grow in your teeth and gums. Mouthwash is an antiseptic. It kills bacteria in the mouth, especially the ones that cause gingivitis and halitosis (bad breath). It’s like soap versus hand sanitizer. One removes food sources for bacteria, the other kills the bacteria."
],
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[
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|
j2lovv
|
why the new Sparc fusion reactor is supposed to work better than current designs.
|
The [New York Times]( URL_0 ) doesn't shed much light on how it will be different. It talks about better magnets, but that doesn't seem like the kind of thing to warrant explanation in 7 scientific articles.
|
Physics
|
explainlikeimfive
|
{
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"text": [
"There's lots of big challenges to build a practical fusion reactor, SPARC goes after three of them: 1) You have to confine the plasma so that it doesn't escape, which takes really powerful magnets. To get enough plasma to fuse and be stable, you need a lot. The combination means fusion reactors tend to be really large...the magnets are huge and powerful. SPARC uses a different magnet technology that is much more powerful. Fusion is really sensitive to the magnetic field strength, so a twice as powerful field (what SPARC offers) gives you about four times as much power in the plasma. This means you can build smaller. This is simpler and cheaper, although the magnets themselves are relatively even more expensive. 2) You need a vacuum for the plasma to live in, and the magnets need to surround that. Since the magnets are huge and need to wrap the vacuum bottle, it's really hard to change anything once it's built, the chamber is basically \"wrapped\" in enormous magnets. SPARC leverages some of the magnet properties to allow them to \"open up\" the magnets in a practical way so you can maintain or swap out the vacuum vessel relatively easily. 3) You need a way to capture the heat from the reaction (so you can generate power) contain escaping radiation. This is called the \"blanket\" in a fusion reactor and it's a difficult component. SPARC uses a molten salt (very hot liquid mineral) instead of a solid blanket. This simplifies the power side and mechanical complexity, and is easy to replace/maintain. All in theory.",
"Well they use better superconductive coils to generate the magnetic field. And the potential energy production from fusion is linked to the strength of the magnetic field to the power of 4. So doubling the field strength would increase the yield by factor 16. I'm not an expert on this, but superconductors are a pretty complicated science. There are different types, and they have different limits when it comes to field strength and temperature requirements. And somehow we have much to discover because the best ones we have are super complicated ceramic mixtures and we don't really know how much better we can make them. SPARC will likely be the first experimental reactor that actually produces more energy than it consumes.",
"The seven papers lay out the “physics basis” for SPARC. Publishing the physics basis is an important step for any big experiment, and gives a lot of credibility to a project like this. They basically say, “here’s exactly what we plan to do, here’s all the math and analysis that says why we believe it will work,” and then the rest of the scientific community gets to read through it in detail. The reason there is more than one paper is because they need to show that each different system in SPARC will work. For example, there’s a paper on how they calculate the strength of the magnets they need, and a separate paper on how they need to build the machine to withstand the high temperatures and forces of fusion reactions."
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j2lye0
|
why are US schools funded by property taxes?
|
Economics
|
explainlikeimfive
|
{
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],
"text": [
"Cynically: So that wealthier people don’t have to fund schools in poor school districts. With a giant dose of race related politics in the US thrown in. You can see this play out in the post-segregation era where a lot of predominantly white suburban areas split off from the cities they surrounded to form their own school districts. This kept the mostly poor black kids out of the mostly white middle class schools, and also dried up funding for the schools in poorer areas to achieve the same result as segregation."
],
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|
[
"url"
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[
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|
j2m9fp
|
Why do all of our planets orbit on the same plane, unlike electrons in an atom?
|
Physics
|
explainlikeimfive
|
{
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"text": [
"The planets started out as clumps of matter inside an accretion disk, which spun alongside the growing Sun. Like all spinning bodies, the weight of that disk tends to be pulled outward toward the middle, flattening it out substantially, like pizza dough when the chef throws it up. Because of this, the vast majority of the planetary bodies are going to fall within the same general plane of motion, with only some exceptions.",
"Well, I'll start off by saying that electrons don't actually \"orbit\" the way that physical objects do. An electron orbital is a region around the nucleus where the electron has a high probability of existing, but until it interacts with something, the electron kind of exists in all locations in the orbital at the same time. Quantum mechanics is weird. As for planets, imagine that you have an asteroid belt that is orbiting the sun in all different directions. As planets start to form, they end up moving in the average direction and velocity as all of the parts that made them up. And if you have a bunch of stuff orbiting a center of mass in 3D space, the average motion will always end up being rotation on some plane.",
"Electrons experience a mutually repulsive force that pushes them into goofy “orbitals” that maximize their distance from eachother while minimizing their distance from the attractive force from the nucleus. There’s also more complex spin pairing and waveform behavior that’s not really ELI5 material - electrons have a number of internal and external forces acting on them to create some truly bizarre behavior. They don’t actually circle the nucleus like little planets. Planets and stars don’t have any repulsive force or quantum spin pairing, just the attractive force of gravity. This force flattens out the debris clouds around young stars into a colossal ring system like what you see around Saturn. The spinning motion of the star itself starts to create a flat disk (think spinning a pizza crust) near the center, and then the gravity of the disk itself starts further flattening the entire solar system. If your orbit *isn’t* in the disk, you’re constantly being pulled “up” or “down” while at the edges of the orbit by the gravity of the disk. Over time, this flattens the orbit of almost every major object in the solar system into a flat plane. The planets eventually form out of this debris disk and maintain their flat orbits.",
"Because all of the planets were formed from the same disc of rotating material, so they inherited their rotation about this center from that disc. Why was it a disc instead of a sphere? Well, rotating things tend to \"bulge out\" along the plane of rotation. This is why the spinning earth bulges out along the equator. Only slightly because the Earth is mostly solid. For a cloud of basically dust and small rocks, there isn't really much that would keep it together so it bulges and spreads out a lot, forming a disc. Why did it start rotating to begin with? Well, a cloud of dust and small rocks has an overall center of gravity. Everything would be trying to reach that point. But that is a single point and there is a lot of dust and rocks, so they all can't get there at the same time. Also, as they try all move toward that point, they crowd together and begin bumping into each other. The end result is that most of this material misses that center of gravity and instead goes around it. While they all won't miss it in the same direction, some direction will have more particles missing it than other directions which creates a kind of imbalance and imparts a slight rotation in that direction to the overall cloud. This causes future \"misses\" to miss in that direction, increasing the rotation in that direction until everything is rotating in that direction."
],
"score": [
15,
12,
5,
5
],
"text_urls": [
[],
[],
[],
[]
]
}
|
[
"url"
] |
[
"url"
] |
|
j2mkfi
|
How do seedless grapes carry on their species?
|
My English sucks, sorry. Hope you understand my question.
|
Biology
|
explainlikeimfive
|
{
"a_id": [
"g7670ll",
"g767f03"
],
"text": [
"They don't. Seedless grapes, like many domesticated plants, require human intervention to spread. New seedless grape vines are grown by cutting a piece from an existing vine and planting it in the ground.",
"Grafting. The plants don't reproduce, because they have no seeds and are therefore sterile. So botanists and gardeners cut parts off of plants that produce the desired fruit and attach it to other plants. They continue to grow on the new plant, and the process is repeated indefinitely. [Check this out for more info.]( URL_0 .)"
],
"score": [
70,
8
],
"text_urls": [
[],
[
"https://wonderopolis.org/wonder/how-are-seedless-fruits-made#:~:text=For%20example%2C%20to%20make%20seedless,are%20made%20from%20existing%20plants.&text=The%20cut%20ends%20are%20then,that%20they%20produce%20seedless%20fruit"
]
]
}
|
[
"url"
] |
[
"url"
] |
j2mz71
|
Are young kids actually attracted by the bright colors generally used for their toys? If so, why is that?
|
Other
|
explainlikeimfive
|
{
"a_id": [
"g769wmc"
],
"text": [
"Yes, and it's because babies [learn to see]( URL_0 ). Their brain needs to learn how to control the muscles that focus the lenses inside the eyes and the muscles that move the eyes, and also how to interpret the patterns of brightness and colors into actual images. Having brightly-colored toys they can reach and touch helps their brains form a correlation between depth perception and how to move their hands to actually reach the objects."
],
"score": [
12
],
"text_urls": [
[
"https://www.aoa.org/healthy-eyes/eye-health-for-life/infant-vision?sso=y"
]
]
}
|
[
"url"
] |
[
"url"
] |
|
j2nor1
|
how the body has developed to not have an upper limit of the fat it can or wants to store
|
The question came up when thinking about phones stopping to charge when the reaching 100% battery. It appears the body keeps accumulating fat even when it's excessive.
|
Biology
|
explainlikeimfive
|
{
"a_id": [
"g76duwa",
"g76dv0v",
"g77j1q0",
"g773ele"
],
"text": [
"Because, historically, it hasn't been a problem. Evolution doesn't have a goal or an end state it is after - it simply 'rewards' traits that grant increased reproductive fitness. Up until the last ~50 years or so, having _too much_ food has not been a problem, so it was rare for people to get so fat that it caused health issues. Since it wasn't a common problem, we never evolved to avoid it.",
"Evolution is a very slow process and obesity wasn't an issue until relatively recently. Its simply too short of a time span for us to to have evolved something like that",
"The body views fat the same way you view money - you can never have enough. We just didn't evolve in an environment where food was freely available and if you one day walked into a place that was just filled with free cash that you could take you would behave exactly like average people at a buffet - even if you were fine for money.",
"In order for evolution to weed out a certain trait or effect, a lot of people have to die from it before they have a chance to procreate. Let’s think about cancer as an example. Some people do have a genetic disposition to get cancer more likely than other people. Why? Wouldn’t evolution weed that out? Well, it did weed it out. People who had a genetic disposition to get cancer before age 16 did probably die of it before procreating often enough that those genes are functionally gone from the pool. However, if you have a gene that says “I get cancer at age 50” then evolution doesn’t really have a chance to operate upon that, because most people who will procreate have done so by age 50. This is why a lot of people in their upper years still get cancer, but younger people much more rarely so. I guess you could say that some men procreate after 50. And maybe some villages have a lower chance of surviving as a whole if their age 50+ people all die and aren’t there to lead them. But those are much more indirect effects and seem to have been overwhelmed by other factors in our evolution. So why do people get obese without limit? Because not enough people did so and died from it before the age of procreation. Food wasn’t so plentiful throughout our evolution. And while we know today that being obese has long term health impacts and can even lead to your early death, how many of those deaths are before age 16 or so? Not enough to drive evolution."
],
"score": [
43,
11,
3,
3
],
"text_urls": [
[],
[],
[],
[]
]
}
|
[
"url"
] |
[
"url"
] |
j2nr8j
|
Why is it that species like parrots can mimic or talk like human phrases but species like monkeys/apes can't even though they're closely related to us genetically?
|
Biology
|
explainlikeimfive
|
{
"a_id": [
"g76eszq"
],
"text": [
"The great apes don’t have the skull/vocal structure or command to make the complex sounds humans make. They’ve evolved down a different path that emphasized sound volume and jaw strength. Parrots have evolved a highly complex vocalizing system that can reproduce the sounds, although their method of doing so is very different."
],
"score": [
8
],
"text_urls": [
[]
]
}
|
[
"url"
] |
[
"url"
] |
|
j2nsg8
|
Can someone explain how a leak on the International Space Station is not a huge deal (no decompression)? Also, how are they making air fast enough where this isn't an issue? How is the air replaced?
|
Just read an article how they have been looking for a leak for some time, but it doesn't sound like a big deal.
|
Other
|
explainlikeimfive
|
{
"a_id": [
"g76e6op",
"g76i9bi"
],
"text": [
"Two reasons. 1. The flow rate of air into space is proportional to the size of the hole. A very small hole leaks air very slowly. 2. The ISS has atmosphere reserves to add more air into the system as needed, since they inevitably lose some every time they open any exterior hatch.",
"It must be a very very small leak. Any leak larger than that they would find quickly. Leaks of that size allow very few molecules through them and at a very slow rate; they leak out in a quantity much smaller than the amount of air and reserve air on the space station."
],
"score": [
12,
3
],
"text_urls": [
[],
[]
]
}
|
[
"url"
] |
[
"url"
] |
j2nwg6
|
Why do wheels look like they slow down when they’re going fast?
|
Physics
|
explainlikeimfive
|
{
"a_id": [
"g76h45d"
],
"text": [
"In tv and movies it has to do with the frame rate. If the wheel makes one full rotation between each frame it looks like the wheel is standing still. So from a stop it looks like the wheel accelerates, then as the rotation gets closer to the frame rate it appears to slow down until it stops, if acceleration continues it will appear to go backwards. In real life is tricker. Our brains do the best they can to interpret a scene. When theres ambiguity our brain makes its best guess. sometimes its wrong. When a wheel is moving slowly its easy to track. The faster its goes the harder it is to pick out the elements needed to determine direction and speed. Think of the spinning dancer illusion. With no details our brain will switch back and forth on the direction making its best guess at any given time. At least that's the best hypothesis I've read."
],
"score": [
3
],
"text_urls": [
[]
]
}
|
[
"url"
] |
[
"url"
] |
|
j2o8v2
|
Do green screens have to be green? Can't they be blue or any other color? What makes the green very usedul and different in video editing?
|
Technology
|
explainlikeimfive
|
{
"a_id": [
"g76hptv",
"g76j4h1"
],
"text": [
"No. It can be any color. Often it's blue. The most important part is that nothing else on the screen has the same color. That is easiest to avoid by using green screens. But you'll just as often see blue really. Essentially you have a computer say \"everything with < color > will be transparent and behind that is something else which can be anything. Cgi or a clip from say inside the star wars spaceships.",
"Green screens use the colour green because modern digital cameras have a lot more green receptors in them. This is similar to the human eye which evolved to see more green (Nature) This is all from memory but I remember watching an interesting documentary on how the technology has developed over time. I think that the colour blue was used in the past, not sure why. I do however know that green is used today due to the way cameras pick up green light, which leads to higher resolution images and a clearer \"green screen\" effect. Sorry for the half assed explanation, it's past my bedtime."
],
"score": [
6,
3
],
"text_urls": [
[],
[]
]
}
|
[
"url"
] |
[
"url"
] |
|
j2o951
|
When two people are talking at the same time, ears can detect the separate voices. Why can't microphones/speakers do the same?
|
Technology
|
explainlikeimfive
|
{
"a_id": [
"g76hwn0",
"g76lfei",
"g76i3e6"
],
"text": [
"You have the most complex device in the known universe in your head, and a large portion of it is tasked with deciphering human speech. A microphone just picks up ambient noise and converts it to an electric signal. There’s really no comparison. Your brain is a biological supercomputer that can dedicate enormous processing power to signal analysis. You can write software to try and pick apart the two voices and isolate the two signals, but doing it in real time requires a lot of processing power.",
"Your ears only detect vibrations, same as a microphone. Your brain is what separates out voices using beamforming, frequency analysis, and natural language recognition. We *can* have an electronic computer do all of those things to an array of microphones. Beamforming is simple trigonometry, frequency analysis is slightly more complex math but nothing a computer can't do, but natural language recognition is still some way off from being perfected - just look at the automatic closed captions on YouTube.",
"Microphones and speakers don't have brains. The ears are picking up everything just the same. Its the brain that does the filtering. And not everyone can do it. One reason I do not like large gatherings is my difficulty filtering out all the voices. It can get overwhelming."
],
"score": [
18,
7,
6
],
"text_urls": [
[],
[],
[]
]
}
|
[
"url"
] |
[
"url"
] |
|
j2ocp1
|
How are wild animals able to drink unfiltered water and not get sick?
|
Biology
|
explainlikeimfive
|
{
"a_id": [
"g76ic77",
"g76i9nj"
],
"text": [
"They get sick all the time, and either die or recover. We just don't see the sick ones. Waterborne parasites don't necessarily make their host sick- it's not evolutionarily favorable to kill the host. So many animals carry parasites relatively asymptomatically.",
"They do get sick. Humans purify the water to reduce our risk of tapeworm bullshit to effectively zero. An animal doesn’t have the capacity to do that, and is risking infection with each drink. They do understand that cold, flowing water is safer than a stagnant pond though. You won’t see many animals take a drink from a nasty sludge pool."
],
"score": [
6,
5
],
"text_urls": [
[],
[]
]
}
|
[
"url"
] |
[
"url"
] |
|
j2oo4k
|
Why do middle-aged women often have a distinct short hairstyle?
|
Other
|
explainlikeimfive
|
{
"a_id": [
"g76l66s",
"g76lywj",
"g77cjej",
"g76lllt",
"g76ogmj",
"g76z27f"
],
"text": [
"I can’t speak directly to middle age women, however in general, older women tend to have sorter hair because often shorter hair is easier to take care of. And little old ladies tend to have perms or similar, again for ease of care, and like with men, as women age, hair does tend to thin out a bit, so perms give added volume to thin hair. So there isn’t a super specific reason, aside from shorter hair often requires less overall time and effort to maintain than long hair.",
"I'm a 42 year old woman and I can absolutely say I chopped off my mid-back locks for a shaved head (more drastic than the op is asking about but thats me) cause I don't have time for that shit anymore. I have extremely thick hair and it would literally take a day (24 hours) to fully dry. I would end up wearing a ponytail all the time and so I decided to chop it all of for a more carefree hairdo. Also? I love the freedom of the shaved head, but hate how it looks. So im growing it back out. But middle aged ladies mileage may vary.",
"Because when you hit 40, you realise that long hair is a pain in goddam arse. It costs too much to maintain and who are we trying to impress anyway? Other women? Men? Or just trying to conform. We realise that we have no more fucks left to give and we become happy little swamp witches. The end.",
"Long hair is a symbol of good health and status in humans and other animals. You have to be healthy enough to grow it out and have the means to take care of it. This is important when younger so you can attract a mate. Once settled down, long hair is a disadvantage once people have grabby babies that like to yank hair. In addition, having short hair is easier to maintain when you are sleep deprived from children. Once people are used to the benefits of taking care of short hair, they often don't want to go back to long hair.",
"A lot of women cut their hair after pregnancy because while your hair pretty much stops falling out during pregnancy it falls out in a big bunch after a few weeks (which is the hair follicles returning to normal after their growth cycle having been disturbed by pregnancy hormones). A lot of women cut it because they can’t be faffed to take care of long hair. It’s time-consuming and, depending on the hair and if/how you style/colour it, can be VERY expensive. A lot of women have long hair for most of their lives and feel the need to change when they enter the 35+ zone. You generally find yourself around that time and can decide what YOU want as opposed to what society is expecting of you.",
"When you get older, your hair may get thinner (women can lose hair with age, just like men, but instead of \"male pattern baldness\", women tend to lose it all over the head so there's just less hair all over), so it has less body and it may be more obvious that you have less hair. If you cut it short, then the hair tends to poof out more as it's not being weighted down by longer, heavier strands. This makes it look fuller and conceals that you have fewer hair follicles overall. For this same reason, many women start to get perms when they get older as the perm adds bounce and volume to the hair. Also, as you get older, you may be less interested in attracting men. So you're getting your hair done for yourself, not for someone else. A lot of guys like longer hair in women but it takes time to care for so when you're doing it just for yourself, you go for the easier hair care situation. After menopause, your hair may be drier and so it starts lacking the shine that youthful hair has, and it becomes more brittle. Shorter hair makes this less of a problem. Many older women dye their hair as they get older, which can damage hair, and shorter hair becomes easier to care for in this context."
],
"score": [
12,
9,
3,
3,
3,
3
],
"text_urls": [
[],
[],
[],
[],
[],
[]
]
}
|
[
"url"
] |
[
"url"
] |
|
j2ov41
|
Why do coyotes usually look so scraggly and unhealthy, while other common predators don't?
|
Other
|
explainlikeimfive
|
{
"a_id": [
"g76snb1"
],
"text": [
"Mainly because an urban/suburban environment isn't a great one for coyotes but due to habitat destruction, they may or may not have a ton of choice to live in or near areas where humans live. You typically don't see any other larger carnivores in these areas and for good reason. They're also more likely to eat stuff like garbage in cities. Combine all of these together, and they're going to look a lot more rough than [a wild coyote]( URL_0 ) likely would."
],
"score": [
9
],
"text_urls": [
[
"https://cdn.cms.prod.nypr.digital/images/2018_12_coyote.2e16d0ba.fill-661x496.jpg"
]
]
}
|
[
"url"
] |
[
"url"
] |
|
j2pm51
|
why does it take human babies so long to be able to walk/do things on their own when other mammals can do it within hours after birth?
|
Biology
|
explainlikeimfive
|
{
"a_id": [
"g76u3b6"
],
"text": [
"Humans are born developmentally early, relative to many other animals, so that we don't get stuck inside. The problem is brains...humans have huge brains relative to our body size, and that brain has to get through mom's pelvis. This means you \\*have\\* to get the baby out at about 9 months or it's not coming out at all. But at 9 months we haven't developed enough to walk or do things so we remain almost totally dependent on mom for locomotion for another 6 months or so. In an ideal world (for baby, anyway), gestation would be more like 16 months and babies would come out ready to crawl, or 24 months and they'd come out ready to walk, but pelvises didn't keep up with brain size and our current system works well enough that evolution doesn't really care."
],
"score": [
24
],
"text_urls": [
[]
]
}
|
[
"url"
] |
[
"url"
] |
|
j2ppiz
|
Why is it called the human race and not the human species?
|
Biology
|
explainlikeimfive
|
{
"a_id": [
"g76t0it"
],
"text": [
"The word \"race\" existed long before the modern scientific concept of species. \"Race\" in the way it's used in the phrase \"human race\" dates back to the 1500s, and comes from the Italian \"razza\" which meant \"race, breed, lineage, family\"."
],
"score": [
24
],
"text_urls": [
[]
]
}
|
[
"url"
] |
[
"url"
] |
|
j2q87r
|
What are those white semi-circles under your finger nails?
|
They are by the cuticle and are on all the fingers but most noticeable on the thumbs.
|
Biology
|
explainlikeimfive
|
{
"a_id": [
"g76ylix"
],
"text": [
"It's the **Lunula**, structurally involved in creating new nail material and pushing it outward as the nail grows."
],
"score": [
5
],
"text_urls": [
[]
]
}
|
[
"url"
] |
[
"url"
] |
j2qfcr
|
How is that animals instinctively know about parenting while humans need to learn handling babies?
|
Biology
|
explainlikeimfive
|
{
"a_id": [
"g7702ww",
"g772to2"
],
"text": [
"Not sure I can answer the question but you might need to clarify what you mean by animals instinctively *knowing* how to parent and humans needing to \"learn handling babies\". Most humans are capable of caring for their babies pretty well without being taught. Some of it is instinctual (well I know I need to eat every now and then so maybe this tiny me needs to eat too), some of it's learned (okay, my baby cries when I do *this* so maybe I won't do it anymore). Additionally, animals tend to have larger litters because offspring have a higher chance of dying. This has a dual benefit that we normally only see the offspring that were taken care of properly, and the animal parent gets more experience at raising young. Humans normally only have a few chances to get it right, and often only one chance per birth event. That is going to make us a little more careful and desire to learn more from others before the child is born, to increase the chance the one child we're likely to have survives.",
"> animals instinctively know about parenting Factually not true. My cat was the only one to survive in a litter, more or less because his mum was too young or perhaps too reckless to care about her young ones. Just as there are those in our own species who has no clue how to care for the tiny type of humans, there are those mums in the animal world too."
],
"score": [
9,
5
],
"text_urls": [
[],
[]
]
}
|
[
"url"
] |
[
"url"
] |
|
j2rrfz
|
Why does a dry dishcloth seem to absorb fluids very poorly, whereas an already moist one absorbs it much easier and quicker?
|
I have two (Yeah you read that right, I'm lucky enough to own two) dishcloths in my home I use regularly. The one in the kitchen I use multiple times a day and absorbs any kind of liquid easy and simple everytime I use it. The other one I use a couple of times a week so it dries out more between uses, and for this reason I seem to have to "help it get going" by first wetting it under the tap before I can dry up anything with it. This doesn't make any sense to me at all, a drier cloth should be able to hold more liquid and be more efficient? Please help me understand!
|
Chemistry
|
explainlikeimfive
|
{
"a_id": [
"g77f64m"
],
"text": [
"It is related to the surface tension of the liquid youre trying to mop up. Its the same reason you can alightly overfill a water glass. The dry cloth pushes against the surface of the liquid and has to break the surface tension before wicking and capilary action allows the cloth to absorb the liquid, but a damp cloth breaks the surface tension more readily because the water in the cloth draws the spill into the cloth."
],
"score": [
9
],
"text_urls": [
[]
]
}
|
[
"url"
] |
[
"url"
] |
j2rs6s
|
How does a treadmill machine calculate the calories burned in a session?
|
Other
|
explainlikeimfive
|
{
"a_id": [
"g77auvy"
],
"text": [
"It probably uses the formula MET \\* Weight \\* Time. Weight is your weight in kilograms, which it can measure since you are standing on it. MET is the estimated amount of calories burned while doing a given activity. Time is the time in hours that you have done the activity. The MET values were calculated about a decade ago and are rough estimates though some have very good empirically derived values. While not 100% accurate, it is a good estimate of the number of calories you burned. The inaccuracies come from variance in a person's resting metabolic rate, gender, race, age, ethnic origin, etc. Walking on level ground is between 2.3 and 2.9 METs depending on speed. Running on level ground is around 8 METs, once again depending on speed."
],
"score": [
5
],
"text_urls": [
[]
]
}
|
[
"url"
] |
[
"url"
] |
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