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5vlcmt | Why do humans instinctively look away when we get caught staring at someone? | Biology | explainlikeimfive | {
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"It's not instinctive, it's learned. We all stared as kids, all got told not to stare repeatedly. Now we're adults, we know we can get away with it, right up until they notice.",
"It's a natural response that has been well documented in this [Wikipedia]( URL_0 ) article",
"Primates use staring at another primate as a signal of dominance, with the most dominant animal causing the lesser animal to look away as a submissive gesture. This has been shown in zoos, where they give customers special glasses with printed eyes looking away on the front, so when people look at the dominant silverback gorilla in a cage, he doesn't see this staring as a challenge to his dominance and attack you, smash the glass etc. We are also primates so I would suggest this applies at least to some extent, for example if you were in the club and a massive 6'10\" guy glares at you, you'd probably look away. Think of boxers and mma fighters too squaring off to see who blinks first.",
"It is mainly due to instinctive discomfort either the person is naturally or temporarily shy or feeling shame (terrible haircut, acne that day etc) or the other person is very good looking or the opposite or just makes them feel uncomfortable for another reason hence making them feel discomfort."
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5vldnj | The Pumping Lemma for Regular Languages | I simply don't understand what it is saying. | Mathematics | explainlikeimfive | {
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"A given regular language can be represented as a finite state machine. This machine will only have so many states. However, you can have words in this language that are longer than the number of states. When that's the case, there *must* be a section of the FSM that is repeated. And if a section is repeated once, it can be repeated again (or \"pumped\") to make another string that is also accepted by the language. This is often used in proofs by contradiction. If a language doesn't possess a \"pump\", then it isn't a regular language."
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5vle6l | If in the vacuum of space there are no exterior forces acing on a spacecraft, why can't we continuously speed up the craft to light speed with constant thrust? | Physics | explainlikeimfive | {
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"It takes more and more energy to constantly accelerate a spacecraft. This means that as you approach C the amount of energy that you need to go faster approaches infinity. Sadly humans do not have access to infinite energy so we can never actually reach C.",
"Because of relativity, from your point of view on the ship it may seem like you are always accelerating but from the point of view of someone back on Earth, you will never reach the speed of light. From their perspective, the closer you get to the speed of light the more slowly you would seem to age, the more your length would contract in the direction you are moving and the more your mass would increase. Theoretically, your mass would become infinite if you could reach the speed of light. Since the amount of energy needed accelerate an object is proportional to its mass, you would need an infinite amount of energy to accelerate up to the speed of light."
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5vlhke | What exactly does Pty Ltd mean? | Economics | explainlikeimfive | {
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"Pty = Proprietary = shares are privately held, not publicly traded. Ltd = Limited Liability = the shareholders are not personally liable for the company's finances. The general term for this is [private limited company] ( URL_0 ). In the USA the closest match would be a LLC."
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5vljpt | What is happening when you hold your leg or press your foot a certain way and it begins to tap rapidly for as long as you hold it there? Does that exercise the surrounding muscles? | Biology | explainlikeimfive | {
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"You have muscles that pull in opposite directions so you can move your limbs in both directions. When you hold your foot at the balance point between two opposite muscle groups it shakes because both side are pulling equally. Like a really quick tug-of-war with part of your leg."
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5vlokh | Why is it that words that are incoherent in songs seem so easy to understand after you look up the lyrics? | There are parts in a song which I cant understand and therefore look it up. But after I look it up it seems so clear to me and I don't understand how I couldn't get it the first time. | Other | explainlikeimfive | {
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"Two Words: Confirmation Bias. Basically: When you hear a song and you can't quite catch the lyrics, your brain doesn't know what to listen for, so it can't easily distinguish lyrics; especially if the song is badly mixed (the vocals are too quiet relative to the instruments), or just a background noise. However, once you know the lyrics it becomes much easier for your brain to pick them out of all the other noise, and you hear them clearly. this is because your brain now knows what to listen for. (This was an explanation based on my understanding, having done little research. If you'd like a more 'true' explanation, look at the other comments)"
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5vlpon | Is it just a coincidence that 'Who', 'What', 'When', 'Where', and 'Why' all start with 'Wh' or is there a reason? | Other | explainlikeimfive | {
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"There is a reason. Specifically the grammar of PIE (the earliest ancestor language of modern English that we have a fair working knowledge of) marked interrogatives (words like who, what, when etc) with a prefix that sounded like 'kw'. (I'm no linguist, but I suppose this is kind of like the way English marks questions with a rising final intonation). As PIE morphed into English (via German) the 'kw' prefix became 'hw'. Say both sounds together and notice how similar they are to actually say. Over time the order of the hw got swapped around, and the pronunciation simplified to 'w' in most cases and 'h' in a few words eg. 'how'. Interestingly, PIE also developed along parallel lines into other languages like Latin. And in Latin, interrogatives mostly all start with the letter 'q', another obvious descendant from the 'kw' sound. (For example English 'what' and Latin 'quod')."
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5vltu8 | Why is a healing wound itchy? | Biology | explainlikeimfive | {
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"When you have an open wound, the response is to inflame the area, which means to increase blood flow and heat it up to prevent bacterial growth. The signal we use (inflammatory cytokines) to do this is the same as the signal that we use when parasites latch onto us, so it comes with itching to scratch the non-existent parasite off."
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5vlxbk | How do we think and act as a whole, a single unit(organism), even though we are made up of other, smaller, cells that "think" and act individually? | Biology | explainlikeimfive | {
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"The short answer is that your cells are \"talking\" to each other. Your cells communicate with each other in a number of ways including endocrine and paracrine signals, but thinking and acting are really easy ones to talk about because this just relies on your brain. Your brain is made up of a bunch of nerve cells or neurons that are specialized for sending fast signals. You could say that they operate at the speed of thought if you wanted to get cute about it. Neurons in your brain are connected to your muscles, and neurons in your muscles are connected to your brain. If you want to wave your hand at someone, the idea originates in your brain, and then the brain sends out a coordinated group of signals to the muscles in your shoulder, arm and hand to contract or relax in the correct way to accomplish this action, while monitoring feedback from nerves in the limb and integrating information about its position from your eyes to ensure that things are going right.",
"An interesting analogy here is liquidity. No single H2O molecule is liquid, yet several of them together can be liquid in the right circumstances. In short, if you abstract away from basic building blocks, you will get different types of properties. In a different-but-similar sense, this holds for further abstraction levels, too. E.g. \"How do we think and act as a sports team?\", or further, \"How do we think and act as a culture type?\". Here, too, you could say a team is made up of other, smaller parts (players), and still a team shows properties like aggression levels, tactics, and so on. It's also possible to go into the other direction (compared to your original question), i.e. lower levels of abstraction. Cells are made up of molecules: how can cells duplicate when molecules cannot? Here, too, we see that a level of abstraction showcases properties that different levels do not necessarily show."
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5vly5l | Why would a government want to invest in coal powered power plants as opposed to wind/solar? | Technology | explainlikeimfive | {
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"It shouldn't. There is no economic reason to be investing in coal at this point, as coal is more expensive, more dangerous, more damaging to the environment (and thus to your taxpayers), and less efficient, than more modern forms of energy production. The reason Trump wants to invest in this outmoded technology is because we in the United States have a whole belt of states whose economies have collapsed over the past several decades as coal companies steadily went out of business or got into other fields. Coal - producing states have been left behind by US economic policy. Trump promised to bring coal back to get those states' votes, and it worked. Those states gave him the election. The problem, of course, is that he can't make good on that promise. Coal company execs are on record saying their industry is doomed, it's not going to magically come back just because the president promised it would. Even if we removed all regulation on coal burning plants, it would still be more expensive than wind and solar in most areas of the country at this point due to massive advances in those fields. What needs to happen is an effort to reinvest in former coal producing areas so they can be part of the new energy economy. Factories producing solar panels could be encouraged to move there with the right federal encouragment, and that would provide new economic boosts which would actually survive into the modern era. Coal is an economic dead end.",
"The amount of power that coal plan produces can be easily controlled by the people running the plant. Need more power, burn more coal. Need less power, burn less coal. Wind and Solar on the other hand depend on nature. It's easy to scale down (cover your panels), but you can't make wind power if the wind isn't blowing. So, this brings us to the question of power storage. While I'm sure you've heard that wind / solar is cheaper than coal, that's only when the wind is blowing or the sun is shining. Once you factor in power storage (compressed air, gravity storage, battery, etc...) to power your city when on a calm windless night, it becomes a lot more expensive. So, until we solve the storage problem, coal / oil / gas plants will always have a place. Then, you have to bring in geography. A train / truck will move coal from one place to another easily. You can't move sunshine up to Alaska for example. You get what you get. *edit: typo",
"Because they're trying to prop up a failing industry to save jobs. Because that's easier than finding real solutions to help the people working in those outdated jobs get retrained to do something else.",
"Unlike solar or wind, you can make a crap-load of power with coal. I've worked in coal fired plants that can easily pump out 350 to 600+ MW of power. I think the largest planned solar site might make a 100MW on a good day. Coal is dirty and dangerous, but it will put the lights on at night.",
"Wind and Solar is not stable production. You generate no power when there is no wind with wind turbines. You generate no power when there is no sun with solar. And there is not an efficient way to store the power they generate for future use at the scale needed for the power grid yet. As such solar and wind power is great supplemental power but you still need a primary power source that is more controllable and reliable. Those are currently nuclear, coal, diesel, hydro-electric, and natural gas. Edit(And Geothermal if you are near a volcano).",
"Right now, the best bang for the buck is natural gas, as we are producing more than we ever have in history (byproduct of fracking for oil) and so all new power plants probably will use this technology. Power companies will use whatever is the cheapest and most reliable. Wind and solar are neither of those... yet. Plus as other posters have mentioned, there are storage, weather and geography problems with both wind and solar. Plus there is the environmental impact. What, you didn't think there was any environmental impact from wind or solar? Think again: URL_0 So no matter what technology, someone, somewhere is gonna be screaming about something.",
"Corruption and populism. Modern US politics is largely about getting re-elected. Anyone trying to get elected in coal country had better be selling hope. To a people whose fathers and grandfathers made good union money with a pension, nice house and two cars, hope looks a lot like a return to the past. So that's what he peddles: he tells the voter that unions are the reason coal is gone. He tells her that he's been working to bring coal back but it's hard work and he needs another term. He tells her that, if she works hard and cheap, prays every night and, mostly, votes his slate, coal *will* be back."
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5vly7z | How would an interplanetary civilization measure time? | Physics | explainlikeimfive | {
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"If they have FTL travel without timey-wimey effects, they'd probably use the standard time on the home planet. If multi-racial, they would probably decide which species' system is used through war or diplomacy. If their FTL travel DOES come with time dilation, then they would probably not be traveling to and from frequently enough for them to use a standard system. Any communication would take years just to send a message and get a reply. Any dealings between colonies would probably work on an \"It'll get there when it gets there\" system."
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5vlz8m | How does radiotherapy treat cancer? | What is different at a molecular level about cancer cells that results in radiotherapy being effective? I guess cancer cells, compared to normal healthy cells, are either more easily damaged or less able to recover. Or is something else going on? | Biology | explainlikeimfive | {
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"A common strategy is to fire the beam through the body at differing angles, centered upon the tumor. That way, while the radiation is certainly not good for healthy cells, any one 'path' of healthy cells gets a much more limited dosage than do the tumor cells themselves.",
"Radiation breaks DNA. Cells have the means to fix these breaks, but the system isn't perfect and it doesn't always work. The thing about broken DNA is that you need your DNA to be not broken in order to replicate properly. Depending on where the break is, it could cause the entire cell to die in the process, or to just fail to replicate at all and die of old age. Radiation can break other things about cells as well, but the biggest thing they break is, therefore, the ability to replicate. Cancer cells are cells which are replicating out of control, pretty much as fast as they possibly can. The rest of the cells in the body replicate more slowly, so radiation doesn't damage them as badly. Cancer cells, on the other hand, will be negatively impacted the next time they go to replicate. Which is right now."
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5vlzvo | Why do we need to sleep? Can't we recover whilst being awake and just laying still? | Biology | explainlikeimfive | {
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"The truth is, no one truly knows why we need sleep; we just know that we do. While we understand that we *must* sleep, and we understand at least some of the role sleep plays, medical science still hasn't been able to nail down the why of it all. The biggest hurdle to understanding why we sleep has been that the brain activity that occurs during sleep is largely hidden from researchers. New methods, still in their infancy, are beginning to help researchers understand the purpose of sleep, though. We know that it must be vital to us as a species, because it remained part of our evolution despite the fact that we are most vulnerable during sleep. We know that there are serious health consequences, up to and including death, if we don't sleep. We know that sleep allows our brains to \"consolidate\" our memories, converting short term memories to long term memories. Sleep also provides the brain an opportunity to 'take out the trash', as it were...cerebral spinal fluid is pushed around the brain during sleep to clear waste chemicals produced as part of a cell's natural activity. There are a lot of theories, but even with all we know, we still are not sure exactly why we sleep."
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5vlzx2 | With the new finding of the seven earth sized planets, how will humans determine whether there is life on them and how long would it take to do? | Technology | explainlikeimfive | {
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"The planets are 39 light years away, so getting a probe or something over there would take quite hundreds of years or more with our current tech at it's best. Fortunately, we don't have to do that. The best thing we can do is to look for signs of the kinds of gases life makes: oxygen, carbon dioxide, methane. When Trappist-1's light shines through the atmosphere of one of the planets, we can watch for which spectrums of light are and aren't filtered out by the atmosphere, which tell us what types of gases are in it. This is of course not SUPER conclusive, but we'll be able to get proper answers on it within the decade. And there's plenty of other exoplanets out there to try the same tricks on. We've been discovering exoplanets at an enormous rate lately, which is amazing since it took until 1992 to fundamentally find and prove the existence of planets around other stars, and now we've got bucketfuls of data about 'em to sort through and start oogling."
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5vm4gw | Why does it seem that the geniuses of the world, be it mathematical, technological or even artful, seem to be either extremely reclusive in nature or extremely overconfident? | Other | explainlikeimfive | {
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"If you are a genius, you have a clear reason to be confident: you are smarter than most of the people around you. If you are genius, you have a clear reason to be reclusive: the people around you are probably rather boring compared to your own ideas, and don't even understand what you're talking about much of the time.",
"Showing genius means rocking the boat, so a certain amount of willingness to buck social norms is kind of a must."
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5vmcia | How does Google know that you get the letters correct in a captcha! if they were designed so that computers can't read them? | Technology | explainlikeimfive | {
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"There are two(ish) main types of captcha: 1) Computer generated word images. In this case, it's obvious why the computer can know if you've typed it in correctly. 2) Not computer generated captcha. This is the kind that comes with two word-images. Only one of these words is actually the human test. The other one is there so that the computer learns what most people write it out as. Once enough people have written an identical answer for that word, it can become one of the testing word-images. So during a particular captcha entry, you are simultaneously proving you're a human, and teaching the computer what a particular word-image says. Interestingly, some captchas incorporate words from scanned books that the google intelligence can't decipher. These are the non-test words. When answering these captchas, you are both helping create a new test word-image, and helping digitize books!",
"The same capatcha is often given to many users, and for Google's two-word recapatcha, one of the words is a known by the computer, the other is unknown"
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5vmera | Can SETI listen to radio activity from TRAPPIST-1? | Technology | explainlikeimfive | {
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"They can. May not be worthwhile, though, as from what I recall the system is pretty young (possibly less than a billion years old). We can also send a signal at them directly, although it'd take 40 years for the signal to reach them, and another 40 years for their response (if any) to get back. Interestingly enough, on the (**highly** unlikely) chance that they managed to hear the Berlin Olympic broadcast and figure out it was coming from our system, their response could be coming any day now.",
"Sure. But keep in mind that system is 40 light years away. You'd need a pretty substantial amount of power to transmit a signal over that distance. If you are sending an omnidirectional signal, it'll attenuate (not sure if that's the right word) at the same rate as gravity, a-la the inverse square law due to the spherical expansion of the signal. They might be able to use a directional or focused signal if they knew we were here. If they can do those things with the right amount of power, yeah, we'd be able to hear them. But what we're hearing is 40 years old."
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5vmh6w | Why can you see your legs if you stand really close to a mirror only covering the face/chest. | The shoes are way under the level of the mirror, and their image is reflected if you look at the bottom of the mirror. | Physics | explainlikeimfive | {
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"A mirror doesn't reflect only those things directly in front of it. You're seeing your shoes because of the angle you're looking into the mirror. Think like your eyes are taking a banking billiards shot against the mirror and your shoes are the corner pocket."
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5vmsfi | What is the biological purpose, if any, of male humans developing slowly than females? Is this seen anywhere else in the animal kingdom? | Biology | explainlikeimfive | {
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"Physically, male humans develop slower because they are larger and more massive (mass wise) than females. Growing takes time, and growing too fast isn't good for the body. Emotionally/intellectually this is more challenging. But it is a fact that women(girls) mature faster than men. Girls learn to \"prune\" information and generate more effective brain connections at an earlier age than boys. This means perhaps boys have longer to learn and form views and ideas on the world, but they take longer to do so. Why is this? We're now onto a bit more speculation. In the wild, back when evolution was being selective, it was beneficial for girls to mature quickly so they can start reproducing (girls are the limiting resource in a populations growth rate much more than boys are, because men can have sex with multiple women) and in general the downsides for this (being smaller, perhaps being less creative or forming faster world-views) were acceptable. However, men take the role of \"hunting\" or \"fighting\" (size needed for both). There was also probably typically more pressure on men to be innovative and different (in good and bad ways) due to the likely nature of early-human societies where women predominantly were suited to child care, and men were worth taking a \"risk\" on, due to them being more expendable. If you have 50 men and 50 women, and 30 of the men die because they experimented with something stupid, or because they were killed by an animal/other tribe, the tribe is still okay because the number of women determine how good the future is. But conversely, it is a bad evolutionary idea if you design women to all be a bit nuts and reckless. ** - I sincerely hope I haven't offended anyone with the above, I am trying to be impartial. In answer to your last question - in species were males are larger than females, yes males will grow slower.",
"I've heard it explained that men mature slower so that they aren't killed by the dominant male or invading males. They rely on a growth spurt after which they may have a chance against a mature male. Think of male lions killing Cubs of previous males as a similar pattern.",
"If females mature faster, then there are more females in the breeding population. In theory, a species only needs one breeding-age male to propagate, but more breeding females means more babies."
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5vn13h | How does your skin deal with body size changes and is there any possibility for a person to go from a very large size to a small size without any excess skin (and the reverse; to gain a large amount of weight, without getting stretch marks)? | When people lose/gain weight or muscle mass, so the surface area of the body is either reduced or increased, does your body kill/create skin cells to keep up with the size change or does it only stretch (or maybe a combination of both)? Is there a rate of weight loss or gain that is shown to be slow enough to allow the skin to keep up with the change to avoid stretch marks or excess skin? And with the size change, is there any change in the amount of hair follicles on the surface of the skin (if you gain more surface area, are the hair follicles just more dispersed, or are new ones being created as you gain surface area of the skin)? | Biology | explainlikeimfive | {
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"I went from 160 to 215 last summer when I worked the pasture at my grandparents house. My grandma fed me too well (first world problems, amiright) and now I have stretch marks everywhere. I would love to know how to get rid of them and keep away excess skin while losing weight.",
"Can't speak for what happens to the cells and follicles, but lots of people gain and lose weight without any signs on their skin. Some even gain or lose very little weight but still get stretch marks or loose skin. I've read that people suggest it's genetics that determines how your skin reacts. But I imagine as a general rule, slower is better."
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5vn2j4 | What exactly causes the explosion to be so large when a nuclear bomb is detonated? | Can splitting an atom really cause an explosion to be that large? | Physics | explainlikeimfive | {
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"The simple answer is yes. Modern bombs run on fusion energy, but the principle of converting rest mass into energy remains the same. Other bomb methods are converting chemical bond energy into energy, and on the scale of nuclear physics chemical bonds are weak. Really weak. How powerful? Well a modern hydrogen nuke gives out over 1 megaton of energy, or 1 billion tons of TNT. It is difficult to even explain how insanely powerful that is. If you want to be scared then the largest one ever test was a 50 megaton nuke. This is a great little app to show you the effects these bombs would have URL_0",
"Yes, it can, but it's not just splitting one atom; it's the chain reaction of all of the atoms. The nucleus of an atom is held together by what's called binding energy. When it gets split, you now have 2 or more nuclei, but the total binding energy of the parts is lower than the binding energy of the initial single nucleus. That extra energy is the explosion. The fission of one atom of Plutonium 239 generates 3.318 ×10^-11 Joules, which is tiny, but single kilogram of plutonium contains 2.46x10^24 atoms. Bonus trivia: Most modern nuclear weapons use fusion as their primary energy source. A small fission primary sets of a chain reaction where lighter elements are fused together to make heavier ones, releasing even more energy that fission can."
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5vn3pb | Why do toddlers walk with their hands near their chest, rather than at their sides like a person usually walks? Is this in any way beneficial for them? | Other | explainlikeimfive | {
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"Toddlers fall over a lot. Having the hands closer to the face puts them in a good position to catch their relatively massive head."
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5vn4py | How did Denmark become such a large pork exporter? | Although it trails USA, Germany and Spain in pork export today, but still seems remarkable since: * population < 6 million * very high average income, high education level (so wages are high) * high standard for animal welfare (so cost of raising pigs must be high) | Economics | explainlikeimfive | {
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"Only a guess but i know Denmark from a lot of visits. In the rural areas you often see massive Pig Farms. 1) Geographically very flat, lots of farmland 2) Pretty stable weather, not too hot in the summer and not too cold in the Winter 3) Property value in central Denmark is quite low so big industrial farming is possible 4) Connects to Germany and has a lot of Ports so Export is relatively easy 5) Pig farming has a lot of tradition there i think Edit: Formatting on the phone is shit From what i can remember theres also economical factors. Small farms couldnt survive because of low prices so a lot of small farms got eaten up by larger ones who could more easily get deals with export firms because its easier to deal with one big supplier than with a lot of smaller ones.",
"it largely comes down to historical and geographical reasons. geographically Denmark is very flat, and at some point in the last 1000 years, i cant remember exactly when, Denmark was \"manually overhauled\" from having loads of non-farmed land like bogs and plains, to becoming largely fields. because of this happening fairly early, farms have been the backbone of the danish economy for centuries. because of denmark being a seafairing nation, and the generally fortunate location, trade has always been abundant, which made the country rich. then, in the first world war, denmark declared itself neutral. at the same time, a lot of food was needed at the relativly close fronts of the war, so pig farmers made insane amount of money selling goulash and other pig products to armies. in denmark, these people are reffered to as \"goulash barons\", as they had money to live lavishly. TL;DR easy land to farm, lucky incidents throughout history."
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5vn7y3 | Which type of poison was used to kill Kim Jong Nam by just rubbing if on his face? | Chemistry | explainlikeimfive | {
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"They probably used something like ricin, a biologically-generated poison kind of like boccilism... Even a tiny amount ingested will kill you, and an even tinier amount inhaled will kill you. The woman had it in a plastic bag or something and smeared it into his face, so he inhaled it. She then washed her hands so she wouldn't poison herself."
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5vnee9 | The discovery of 7 Earth-like planets. TRAPPIST-1 is a star 39 light years away. And scientists found 7 planets the size(ish) of Earth orbiting it? Or am I completely lost? What am I missing here? | Other | explainlikeimfive | {
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"You got it right. 7 planets roughly Earth-sized (+ or - about 25%), 3 of them in what they think would be the habitable zone for life like we have on Earth. The star is an ultra-cool red dwarf, which is about 8-11% the size of our Sun, and has a surface temperature about 41% that of the Sun. Because of how close they are to their star, the one furthest from the star has a year about as long as 20 of our days and the rest are shorter than that. Since they are so close, they expect all of them to be tidally locked, meaning the same side is always facing the star, similar to how our Moon always has the same side facing us.",
"The star is a relatively small star which means that it doesn't emit as much heat as our Sun, but this also means that it will last a lot longer than our Sun. Because the star is relatively dim it is easier to see when a planet passes between that star in an orbit since the light reaching us from the star dims a little, if you keep watching the star and notice a pattern to the diming you can plot where planets are. For more on this - URL_0"
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5vnhha | Why do we tend to remember exactly where we were when we learned bad news (that may not effect us personally, such as something on the news)? | For instance, when the 9/11 attacks hit, I can tell you that I was in high school, but home sick that day. It was my habit to sleep with the radio going so when I returned to bed, I had it on and normal stuff was happening. Then all of a sudden I wake up and there's nothing but talk of the attacks. I can also tell you that, a few years earlier, I was standing in front of the TV on my family's boat when news broke of Princess Diana's fatal crash. I understand this happens, not just me. Some tragic event takes place and years later one can recall where they were and/or what they were doing when they heard about it. Why is this/how does it happen? Is there a name for the phenomenon? | Biology | explainlikeimfive | {
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"Firstly, keep in mind that as humans, we learn from experience, and we must remember our experiences to retain this. Very negative experiences or anything else that will cause a significant emotional reaction (e.g. bad news) is something we, as humans, evolved to remember very well. The emotional network of the brain also has a part in memory, and it will enhance and reinforce \"bad\" memories. In particular, we best remember the \"relevant\" details. So, if you were mugged, you might remember exactly what the person and the gun looked like, but you may forget the name of the street. We remember bad events in an effort to avoid them. This isn't THAT relevant nowadays, but 20,000 years ago, a caveman might remember that a pink snake bite killed his best friend. Or a cavewoman might remember the location where her younger sister was killed. Such events are important to remember in an effort to see that history does not repeat itself."
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5vni9l | Why do people tend to behave more poorly on Facebook despite a complete lack of anonymity? | I know this is **extremely generalized**, but, why is it that people tend to behave worse on Facebook even though your real identity is literally on display? You'd think that that fact alone would cause people to act completely differently. Compare that to a site like Reddit; people here have the ability to be completely anonymous and have multiple accounts, and yet most seem to follow very particular expectations and social rules. Edit: Grammar | Technology | explainlikeimfive | {
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"Anonymity is a very powerful promoter of bad behavior, but it is not the only one. Two things that help promote good behavior is consequences and our natural empathy. On facebook there are somewhat limited consequences, especially when interacting with strangers. Tom Jones from Hawaii may be able to see that you are Cindy Feldman from Florida, but there may not be any meaningful way that he can retaliate against you being a jerk with that information. To the second point, when you interact face to face there are powerful factors that are at play in most people. Seeing actual other people in pain and suffering can cause mirrored emotions ourselves. This natural empathy is short circuited not by our own anonymity, but by the anonymity of our victim. They are a random avatar on the computer screen, not a breathing person whose mom is in the hospital, whose face is twisting in pain at an insult, who just stopped to help us jump our car, etc. Faceboom turns the wold into a giant game of Sims where others are just AI that we can interact with.",
"From my experience, I believe there are two very distinct clades of people on Facebook. You have those people who abstain from politics altogether (like myself) and then you have the rest who do the exact opposite and make Facebook their political soapbox. Why does clade B behave more poorly than you might otherwise think? It's because all of those friends who disagree with them politically or those friends who fall into clade A defriended them a long time ago and thus they know full well that they're talking to a tribal audience! This results in an echo chamber situation. URL_0 Rush Limbaugh, Sean Hannity etc aren't successful because they aim for inclusiveness, they are successful because they have a core audience whose beliefs chime with their own. And as their careers took off, they learned that more invective and more bombast meant more positive feedback from their headbanging crowds. This is exactly what happened with Donald Trump, whether you agree with him or not. Their careers are nothing but long positive feedback loops of frothy anger and rage aimed at one side of the political divide. Thus, you have Facebook and people acting like fools. My mom fits this bill to a T. She says the most vile things on Facebook sometimes and she no longer has any leftward leaning friends to smack her down a peg. So she's become conditioned to only say things which earn her \"RIGHT ON, BRO\"S and \"FUCK YEAH\"s from whatever friends she has left. So sad.",
"I thought it was just because Facebook was for everyone and Reddit attracted a less stupid/aggressive demographic."
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5vnn9b | The difference between a strait, sound, and a channel in geography | Other | explainlikeimfive | {
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"A strait is a narrow connection, usually between two \"distinct\" bodies of water. For example, the Strait of Gibraltar connects the Mediterranean Sea with the Atlantic. A channel is usually much wider, and is usually defined as a body of water in and of itself. Often, the two bodies of water it connects are not considered to be different; rather it is defined by the land masses it separates. E.g. the English Channel connects to the Atlantic on both sides, or the Mozambique Channel connects to the Indian ocean on both sides. A sound is normally an inlet or bay, but sometimes it's a strait. The word is used very inconsistently in English. edit: accidentally a word"
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5vnone | How come some people never lose their childlike curiosity? | Other | explainlikeimfive | {
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"I grew up very sheltered due to poverty, religion and remote location. I maintain a childlike curiosity because there are legitimately a lot of things in this world I have not seen and/or experienced- The latest fascinations have been with pneumatic tubes at the bank, hummus and air conditioning."
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5vnos5 | How do frogs just suddenly appear in areas that experience heavy rain where there wasn't any water before? | I'm from California, and we've obviously been in a drought lately. After the heavy rainstorms, I've been walking to a park near my house when the sun sets, and the croaking of what sounds like hundreds and hundreds of frogs can be heard all throughout the park. There are no bodies of water in the park, so how can the frogs just appear where there wasn't any water before? | Other | explainlikeimfive | {
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"On a mobile, so I apologize if this is choppy. This does happen in arid climates like the Southwest more than you might think. There are special native frogs and toads (like the New Mexico Spadefoot) that will sit underground for a long time, sometimes years*, until a heavy rain hits the area. They can stay underground for so long because they coat themselves in mucus and enter a torpor (very deep sleep) state. Once that perfect rain hits, they'll come up to mate and spawn. This whole process is very quick (on the order of a week or so!). They need to mate, spawn, and the tadpoles need to grow up quickly enough to be independent of standing water. After the mating-fest, the adults will dig back down several feet and wait again. EDIT: Decades might be a bit of an embellishment here...more likely just a few years.",
"While there are possible explanations such as meteorological events like waterspouts that could cause it to \"rain frogs\", the more likely answer is these frogs are actually toads. Toads typically don't live near bodies of water, however they still prefer darker/wet climates to prevent their skin from drying out, so post rainfall is the perfect opportunity for them to come out and eat/mate."
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5vnv2c | Why have we not build a space station on the moon to explore further? | Physics | explainlikeimfive | {
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"Short answer: money. It takes $10,000 to send 1lb of stuff to space. ISS weighs 925,000 lb and it only serves research purposes. If you would like to perform any kind of manufacturing or processing and house a reasonable amount of people (ISS currently houses 6) you can easily multiply that by 100x. And already we're getting close to trillion dollars. Add some money for food, water and other supplies and the cost is astronomical. An undertaking like that would require multiple governments to combine their powers and throw trillions of dollars in an very uncertain investment. Which will probably not happen in the near future because humans just don't play along nicely.",
"It comes down to money and politics. We're absolutely overwhelmed with terrestrial issues at home. Propositions to give NASA or the ESA billions of dollars to go back to a rock in outer space fall on deaf ears. Hell, we can't even fund road maintenance where I live.",
"Not sure but unless they have a fully fledged stockpile of resources to build with on the moon you still have to launch all those materials up to the moon and then build the base and then launch the constructed rocket again from the moon to wherever. You also have to send a bunch of people up there and pay them mucho $$$ and train them and do all the research to see what the effects of long term low gravity moon life would do to the body and bring them back for vacation etc etc. So yeah. A few things to work through I guess. Maybe there's something to it though.",
"Most answers center on money and politics and those are good answers, but there's another that gets ignored a lot: the moon is a seriously hostile environment for technology. Specifically, moon dust. The closest thing to it from all I've read is talcum powder, baby powder. And, if you disturb it, it gets EVERYWHERE and really gums up the works. It would be a huge technical challenge to deal with it in a permanent base. It might be okay once it was built and up and running, but getting to that point would be tough.",
"it's still a gravity well. materials will still need to be brought up from Earth until mining and refining is researched and tested. an asteroid mining station would be the best option",
"We dont need a moon base for further exploration. If we could start from the moon that would be great, but we have to start from earth anyway. Better to send ships into orbit and launch from there. Better because it takes less time, less energy, less fuel, fewer logistical issues. Best place to launch from is actually earth."
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5vo7dj | Why did so many American small fry car companies die in the late 40's-mid 50's? | Other | explainlikeimfive | {
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"Oh, something I can answer. The process you observed (\"consolidation\") happens in many mature industries. When an industry is new and growing, many different firms are founded and develop to exploit a new market, and new product or a new technology. Inevitably, the number of firms decreases through mergers, acquisitions, while the size of the remaining firms increase. A hundred years ago, when cars were a new thing and being adopted by people around the country, there were literally hundreds of car and truck manufacturers. Most did not survive more than a few years. They were too small and underfunded to develop the most competitive products and market position. The largest firms, such as Ford and General Motors out-competed them and put them out of business, or bought them up and integrated them into their own corporate structure. The specific time period to which you refer, the 1950's simply saw a continuation of this market trend. There was continued consolidation as the market matured and growth was more difficult to achieve. By then, there were very few new car buyers. Most buyers were repeat business so competition was fierce. The Big Three were simply more efficient at developing and manufacturing new competitive models at lower cost than the \"independent\" manufacturers (the accepted term for the \"small-fry\" makers you mention. ) In particular, 1953 saw a fierce sales battle between GM (via Chevrolet) and Ford for market share. Both makers flooded the markets with low priced, very competitive cars that were being sold cheaper than the independent makers could ever hope to achieve. Furthermore, some independents made serious management and marketing errors which consumed capital and eroded their competitiveness. For example, Hudson spent almost all their money developing a new small car (the Hudson Jet) and ignored their larger cars. The Jet failed in the marketplace and Hudson did not have enough money left to improve their products. They merged with Nash to form AMC. That firm did well when they specialized in boring, sensible basic cars. 15 year later they decided to expand their line of cars. They spread themselves too thin and has a full range of products they could not afford to develop, and were bought by Renault in 1980. AMC survived with Renault until finally being absorbed by Chrysler. Other independents did not fail, they simply changed strategies. Kaiser - Frazer stopped making cars in the US. They moved their operations to South America and did very well making cars for many years there. Other makers' strategy was to diversify away from auto making altogether. Studebaker and Packard merged. They diversified their operations into many different industries. They stopped making cars in 1966, but prospered in other areas. Over the years various Studebaker divisions were bought, sold and merged with other firms. They were not absorbed by the Big Three. They were absorbed by a wide range of different companies. However, part of Studebaker was never diversified, sold or absorbed. Studebaker still exists today as a [financial firm]( URL_0 )",
"as competition increased the prices fell. large manufacturers could produce more cars more cheaply and flood the market drowning out specialty competitors like Studebaker, URL_0 . then it became a cash-in market as the little guys got some decent buck for turning their company and designs over to one of the big three. it was better than going bankrupt."
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5voh37 | Why are humans the only species on Earth that have gained higher thought? | Biology | explainlikeimfive | {
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"Are we? Lots of animals communicate, build tools and domiciles and even exhibit self awareness when presented with a mirror. It's because we haven't figured out a way to communicate our higher thoughts with them, doesn't mean the don't have them... URL_0"
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5vok7v | Why are radios so complicated? Why can't someone just plug an antenna into a speaker or oscilloscope and catch a frequency? | Basically, I was wondering what all of the components and chips inside of a radio are for | Technology | explainlikeimfive | {
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"You very nearly can just plug an antenna into a speaker and catch a frequency. What you're describing is a 'crystal set' and operates purely on the radio waves without the need for it's own power source. Crystal sets were popular in the 'olden days' as kits for children/introducing people to electronics. In addition to the speaker and antenna you need a couple of extra pieces in order to adjust the frequency you want to listen to. Modern devices contain a lot of extra components that handle amplification of the signal, digital displays, and other additional features of the radio. URL_0",
"Just as you hear with your ears when you hear a noise, voice or music, a radio works on the same principle. In order for your ears to hear a sound the vibrations are transferred through a medium, in this case air. Sound you get out of a radio works in a similar fashion. In this case the 'medium' is a radio wave. What a radio will do is encode the 'information' to be transmitted onto a specific frequency of electromagnetic radiation. I'll leave out the fancy mathematics but essentially all the components of a modern radio will combine the specific frequency of the carrier medium with the 'information' (a song for example). This is then fed into a radio antenna that transmits that combined electromagnetic signal which a radio will pick up if it's tuned to the correct carrier frequency. There are 3 basic ways that you can encode the information you wish to transmit onto an electromagnetic wave. **Amplitude modulation**, **Frequency modulation** or **phase shift modulation**. There are more complicated variations of those but i'll stick with AM and FM as they are the easiest to convey. AM will 'modulate' the carrier frequency with the information by increasing or decreasing the amplitude, that is to say the maximum height the signal will be if you looked at it on oscilloscope. FM works by modulating the frequency instead which requires less power to transmit than AM and allows for more information to be encoded per channel than AM for reasons that get complicated. **TL;DR** AM is simple so a wire of sufficient length will pick up the frequency of a channel potentially transmitting information. FM is more complicated and also amplifying circuits make up the bulk of an FM receiver.",
"Radios have to two things: * latch on to a single frequency while eliminating all the others * amplify that very weak signal into something audible That's the part that is going on between antenna and speaker."
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5voqzh | How did sheep shed their wool before the emergence of humans? | Biology | explainlikeimfive | {
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"Humans have selectively bred a small number of species to help provide better for human needs at the expense of the animals natural survival. Sheep are one of those species. Prior to domestication sheep would have grown a much smaller amount of wool up to the point where it served their needs, like the hair on a bear or a wolf. It doesn't grow indefinitely. Then humans came along and found these relatively docile sheep sitting around and someone realised their wool was very useful to make things like clothing out of. Over many generations humans captured and bred these sheep to harvest their wool from. Humans also realised that by breeding the males and females with the most and best wool, the offspring would usually end up with even more wool than the parents. By repeating this process over time we ended up with the types of sheep we have today, who are completely reliant on humans to regularly shear them and remove the wool. This is domestication and selective breeding. Without us they would suffer many problems like overheating and being far too heavy.",
"Wild sheep do not grow excessive amounts of wool. Domestic sheep have been bred for thousands of years for maximum wool production, and are now dependent on humans.",
"Living on a farm that has a type of sheep that was never bred for wool production. Much like dogs sheep will have a different coat in summer and winter. They keep their top wool over summer for sun protection but they shed the side and stomach for heat reasons. Then in winter they will grow a thick coat all over. Sheep grown for wool production have been specifically bred to be genetic mutants that never shed their wool. Thus they rely on people. Look up shrek the sheep. Was a New Zealand sheep that went for many years without being shawn and had one of the biggest wool coats ever.",
"As others have suggested, the original \"wild\" sheep had shorter hair before selective breeding. With that said... There is an island near where I live that has a wild population of wool sheep. They were left there by the Spanish when they first discovered the island with the hopes that by the time they came back there would be a big herd of sheep. The plan succeeded, but the Spanish never came back, so now the island has a bunch of wooly sheep. They look [like this]( URL_0 ) and have long, nappy hair. As they run through the woods, bits of their dreds/hair get caught on branches and twigs and pull off in little tufts. The result is that their hair gets long, but never, like, crazy long. tl;dr: Even long-haired sheep in the wild don't have that long of hair. It dreds up a bit, and is \"trimmed\" over time by getting pulled off by trees/branches that sheep run into.",
"Same way chickens stood upright and cows survived without antibiotics. They didn't. Humans selectively breed these animals to have the excessive traits they have. Without humans, sheep wouldn't have the extreme amount of wool.",
"This is an example of selective breeding. Humans bred the sheep with the most wool over and over again through many generation. Just as wild cows would never look like what you know a cow as today. Another good example is dogs. We would never see the types of breed diversity we see today in dogs had we not selected traits we like and continuously bred for them.",
"The sheep that that have excess wool are only one type of sheep - the domesticated sheep. Other type of sheep don't grow wool beyond what they need to survive. As its name suggests, humans created this species by selective breeding, that is, mating males and females so that the result would be an animal *more beneficial to humans*. In the case of sheep that means more wool. It's worth noting that one of the requirements for domestication is that the resulting species be useful to humans. So the answer is that domesticated sheep did not exist before humans because humans made them. They would not survive in nature for the most part. All this is true also for other domesticated species, like the cow."
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5vp2dc | How does something like the James Webb Space Telescope cost $8 billion? | It's really hard to comprehend this amount of money and how it would be spent. Has any similar project released easy to understand details about how the money is spent? Even saying something like "$50 million to build the mirrors" doesn't help me understand. That's less than 0.7% of the total, but I still think "wow, why does it cost so much?" I'm not suggesting that it's too much money, it's just very difficult to comprehend where it is all going. | Economics | explainlikeimfive | {
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"Who made it? A huge team of NASA engineers working for years and years to develop technology never seen before. These are real smart dudes who don't work for chump change."
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5vp3v6 | Are 2 in 1 shampoo and conditioner just shampoo and conditioner mixed together or is it a different chemical? | Other | explainlikeimfive | {
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"ELI5 Quick n' Dirty Overview on Formulation Chemistry We've got a bottle of Type A Goo. We've got a bottle of Type B Goo. We want to make a product that contains A and B because the consumers find it convenient. Both A and B turn out to be soluble in water. Unfortunately, when *both* A and B get into the same water, you end up with two separate layers, and that's bad. It's because A and B aren't fully compatible. But the customer still wants the combination - what do you do? There's a variety of things you can try! * Use a surfactant. Surfactants get between the layers when they try to form and mess with the layer boundaries so that they can't separate. * Use a mutual solvent. A mutual solvent is attractive to both A and B. Use enough and they stop fighting over the water. * Reduce the ratios of A or B. Some of the time, this is really necessary. Maybe B interferes with A's function even when they are well-mixed. Maybe a certain level of A just will not work in a B mixture no matter how much mutual solvent or surfactant you use. Or maybe the higher ratios are just not cost-effective! Sometimes you need to compromise. * Play with the pH. There's a decent chance that A or B is an ionic compound, meaning it splits into positive and negative bits in water. Those bits can be chemically altered due to the pH (acidity or basicity) of the water. Fine-tuning the pH can allow for better solubility. * Substitute. Okay, so A and B didn't work together and getting them to play nice is like herding middle schoolers. Well, if C has many of the same properties as B but likes A better, why not use C? So which strategy would your \"2 in 1\" use? Unless you've got a company chemist to ask, you won't know. But my guess would be at least 2-3 techniques off of the above list, possibly along with some trade secret goodness that I'm not privy to. Is it possible that your \"2 in 1\" has the same active components (the ones that do the work) as a separate shampoo and conditioner? Yes. Is it also possible that it uses a different active component for compatibility? Yes again. It is possible that there is a difference in effectiveness in either/both parts when you make a combination product? Oh yes. But the fun part is that hygiene/cosmetic formulation is a *huge* industry, with lots of different combinations, methods, and trade secrets. Studying ingredient lists is going to give you a huge headache. If you're a consumer, my recommendation is... try the different products and see what works for you. If it works, use it. If it doesn't, use it for target practice. As a last note, I will say that all of the formulation techniques I mentioned above have a very strong limitation: toxicity. Since we're dealing with hygiene products, it has to be very safe for body contact and can't poison you if you accidentally ingest it. This is why despite the huge variety of things that *could* go into your product, you will often see similar ingredients or variants of similar ingredients in products from different brands. Ingredients that aren't health-friendly can be very good surfactants/mutual solvents/additives, and an industrial chemist like myself uses them daily - but a cosmetic chemist has to think about the human first.",
"ELI5 version: Chemist here TL;DR: 2-in-1 contain the same main ingredients as stand alone shampoo and conditioner but 2 in 1 products have to use a trick to get the oil to stick to the hair. Longer version: Shampoo cleans away the grease on your hair, including your natural oils that give it shine and keep it healthy. If your hair is stripped of its natural oil coating it looks dull and all fluzzy (tech term, sorry ELI5) Conditioners contain oils aimed at restoring the shine and condition. Stand alone conditioners also have a positively charged ingredient that helps the oil drops stick to the negative charges on hair, but we can't use this in a 2 in 1 as the shampoo molecules are negatively charged and you'd get a snotty gloop if you mix them, as the +ve and -ve molecules stick together. Try it. 2-in-1 products DO contain both the shampoo AND the oil. They work less well than stand alone conditioners because shampoo is designed to clean away oil, and yet you are at the same time trying to deposit new oil, but they do work. So how do you get conditioning oil to stick hair when the product you're using is designed to remove oil? 2-in-1 products achieve this with a trick. When the product is in the bottle the conditioning oil drops are very small; too small to stick to the hair efficiently. The trick is that when the 2 in 1 is diluted in the shower, the small drops stick to each other to make bigger drops. Bigger drops are much better at sticking to hair. That's how you get both REMOVAL of oil and DEPOSITION of oil at the same time. Source: I'm a scientist who works in this industry.",
"Hairstylist checking in: 2 in 1 is basically just a rich shampoo. If it leaves you with the softness/smoothness/healthy-feeling that you like in your hair, then go for it. (Hell my dad is happy using bar-soap... but he has next-to-no hair so he's not going to notice much issue.) Ideally? Shampoo, then condition. And don't rinse it all out. (Stop just as there's no more bubbles. Your hair should still feel 'conditioned') The two serve different purposes: Shampoo for cleansing. Conditioner for replenishing/replacing the oils etc. that you just washed away with the dirt. EDIT: To address many of the comments: * **Short hair** (think men's crew cuts... also applies to women of course!): Washing every day is fine. Your natural oils made in your scalp don't have far to go to coat/protect your hair. If your scalp acts up or your hair feels dry/crispy etc. (especially if bleached), then a conditioner used as above will do you some good. * **Medium length to long hair**: First off, washing every day can be a pain just for the dry-times involved. Second, you're stripping your natural oils each time, and while replacing those with conditioner will do the trick, you'll be using a lot of conditioner over time. Skip a day (or even two), and brush your hair thoroughly to move the oils down the shaft to keep your hair 'naturally' conditioned. BUT if you've got a lot of product, spent time in a smoky environment, swim daily etc. then by all means, wash as often as you need. Same if you tend to be greasy after a day. Brushing may sort that out, but build-up is build-up, so wash/condition as needed. * **Long hair** (and some medium length): The tips of your hair are the oldest. Read: Most damaged, from sun/styling/environment in general. If you're in a rush, or the rest of your hair feels fine, or your natural oils are doing the trick for most of your hair, then just condition the ends. Work it in. Wash the rest of your body. Rinse the ends of the hair, and off you go. (This can even be part of the \"skip shampoo for a day\" routine.) * **IMO**: I'm not terribly concerned with smooth hair coming from silicone ingredients or natural oils. It's the end result that counts. If you want to go the apple-cider vinegar \"natural\" washing care to avoid the chemical cocktails then go for it. My philosophy is that it's all chemicals (including your DNA). Keep an ear out for known carcinogens and the like, but silicone coatings on your hair won't give you autism. /s * **Swimmers**: Wash out the chlorine every time. It's a known damaging chemical. A long rinse in clean water will work but there are \"light\" shampoos for just that, they are gentle soaps/detergents that don't go crazy stripping your hair since you'll be using them a lot. Condition if needed. If you only need a little, try a \"leave-in\" spray conditioner to revitalize the washed-more-than-daily hair.",
"Really all you're getting with those is a moisturizing shampoo. It's pretty difficult to find a product marketed as a 2-in-1 in salon quality brands, which says something. (Consider high quality clothing lines that sell both well-made jeans, and also leggings. So a Walmart, or whatever, brand says, \"look, jeggings!' It is not really to your benefit to buy those jeggings instead of the separate, better quality items. ) However not everyone needs conditioner, and many/most people use it incorrectly. Hair, skin and nail needs vary by person, and also with time, changes in hormones or environment, etc. EDIT: Just woke up, I'm sorry for trash-talking jeggings. Someone else pointed out that the jarred pb & j combo would be a better analogy, so... that.",
"There are a lot of answers from a lot of different folks in this thread. I'm sure as soon as I'm done typing this someone will come in here and tell you I'm wrong. But I'm sitting in a factory that makes 100% of a very well known 2-in-1 line of hair products. The chemical engineer who works with all the formulations reports to the same guy I do, and he's a good friend. I work with these products every day. I've been doing this for almost 23 years now. 2-in-1 shampoo and conditioner is just the usual shampoo formula plus silicone. It contains no part of the usual conditioner formula except the things shampoo and conditioner already have in common. The silicone basically coats your hair and makes it slick, thereby less prone to tangles and it feels \"conditioned\". We are well aware of this because getting processing equipment clean after making a formula with silicone in it is a lot harder than the normal cleaning process. It's a huge pain.",
"Found this really good article from the huff post. As it shows, shampoo and conditioner chemically are incompatible. So 2 in 1 try to get around that by taking some elements of conditioner (eg softening), but you can't get the full effect, as in consecutive usage of shampoo, then conditioner. URL_0",
"2 in 1 shampoo and conditioner is the combination of surfactant to clean the hair and silicone to coat the hair. All mass retail hair cleaning systems basically are just different ratios of surfactant and silicone with various perfumes. 2 in 1 shampoos were probably the last big innovation in hair care. Today most shampoos are 2 in 1s even if they aren't labeled as such. The only real surfactant only products are clarifying shampoos. Source: worked at a major haircare product manufacturer.",
"what about 3 in 1 i like to get the Suave for men 3 in 1 cause its Shampoo , Conditioner and Body Wash. id probably get 4 in 1 if they added toothpaste to the mix.",
"How shampoo and conditioner work (am a hairstylist): So, think of a strand of hair as a tree. Inside there are all the parts that make it grow. This is the cortex layer. The outside is covered with shingle like bark, this is called the cuticle layer. It lays tight against the cortex for protection from brushing, heat styling, and so on. In very healthy, non-chemically treated hair, the cuticle makes the hair feel smooth. Chemical processes and other damage cause the cuticle to be ruffled or some of the shingles to break off. This causes dry, frizzy feeling. Shampoo by itself contains surfactants which are oil/dirt seeking. The molecules open the cuticle layer slightly and surround dirt and oil particles. The other side of the surfactant molecule is attracted to water. When you rise, the cleanser leaves, taking the dirt and oil particles with it. You should rinse completely to get it all out. Next, conditioner can be applied to smooth and close the cuticle. Some reconstructive conditioners also contain keratin, which will replace the broken protein bonds in the cortex and also build a temporary replacement shingle on the cuticle. This is why in decades past, women would do a final rinse with vinegar. The ph helps seal the cuticle shut and makes the bark lie tight against the tree. Conditioner should be applied in a small amount-About the size of a quarter. Start at the end and work to the scalp. By the time you get to the scalp area, the conditioner should be mostly diluted. This provides more help to older, more damaged areas while preventing dull, greasy scalp area. Shampoo and conditioner in one doesn't do a great job of cleaning or conditioning. It is gentle cleanser with a moisturizing agent and something like panthenol, which leaves a wax like coat on the strand, making the cuticle lie flat for a little while. Products like V05, leave in conditioners, and smoothing oils work in a similar manner by smoothing the shingles on the cuticle and coating them so they close. Use too much, the hair strand becomes dull, heavy, and greasy.",
"2 in 1 are a fancy shampoo. If you mix shampoo and conditioner you end up with a crappy substance. Shampoo is supossed to be soap soap works by linking to grease/fat/sebum and water and dragging or off your hair. Conditioner is just grease with perfume to replace the oils removed from tour hair when you used shampoo. Again if you mix them to get this broken down crap.",
"I find its better than just plain shampoo, but I need to leave it in for a few minutes to get the relaxing effect, but it doesn't compare to using actual conditioner and even cheap generic conditioner works better. If you've got naturally straight or very short hair it works quite well, but for curly or long hair you still need real conditioner every few days.",
"A bit of a spin-off question - what about salon conditioners that cost $40 for a small bottle? Do those actually work better?",
"Slightly off topic but I worked for a company back in the mid 80's on Long Island. They mixed and blended shampoo's, conditioners and body & hand moisturizers. One of the biggest farces I ever saw perpetrated on the public was the creation of shampoo's for specific hair colors. We would mix a giant vat of shampoo then drain 1/3 of it out and put in dye that made it look brown so that it could be marketed to brunettes. Then we repeated the process by draining the next third and adding yellow for blondes and the last third with red and orange dye for red heads. All the same shit in three different bottles. I guess women really believed this shit. Then the private labeling where we put the same shampoo in a Revlon bottle as we did a supermarket brand was hilarious.",
"Fun story I heard from a senior exec of a large cosmetics company who had several shampoo, conditioner and 2-in-1 products; Their R & D department worked for several months to produce the best 2-in-1 they could but in testing they discovered that the plain shampoo actually conditioned the hair better. They sold the new formula as a \"new and improved\" shampoo and released a 'new' 2-in-1 which was in fact, the old shampoo.",
"Here's to hoping my old friend Vince is a redditor. He worked on the product development team at P & G that developed Pert, the first 2-in-1. He told me a long time ago how it worked, but I can't remember.",
"My dad owned a shampoo/soap/cosmetics factory when I was a kid. If I remember correctly. 2-in-1 was exactly the same as normal shampoo, but with a higher ratio of the chemicals the act toward making your hair feel soft. Conditioner is a whole different deal.",
"Hmm interesting question since so many fraudulent labelling goes on. I always wonder (as someone who reads ingredients out of interest and bc of nursing school) why no one sues the toothpaste companies for using the exact same ingredients almost every time, not allowing America to have certain beneficial ingredients that every other first world country allows (like xylitol in most toothpastes unless you pay twenty five bucks or more to your dentist) and claiming these toothpastes are all different or better. Same ingredients equals same, I thought it was illegal. So....sorry to go on and on but it pisses me off. Yes, usually. Just less shampoo or sometimes watered down. Also those spray in conditioners are also mostly water, fragrance, dimethicone, and a bit of conditioner at the bottom. They cost twenty bucks and up sometimes. Ridiculous.",
"From /u/hobbitqueen 2 years ago in [this thread]( URL_0 ) > First of all, check out /r/haircarescience. As is mentioned above, shampoos and body washes are both surfactants. They clean the dirt and oil away. The main ingredient is usually SLS, sodium laurel sulfate, which is present in most soaps. Body washes are much harsher than shampoos, just as they are harsher than face washes, because the skin on your body can take much more of a beating than the skin on your face or your hair. Well, your hair can take it but it will become coarse and frizzy. Conditioners add moisture back to your hair when shampoo has stripped it all away. The main ingredient in most conditioners are silicones, usually dimethicone and any other ingredients ending in -cone. These ingredients coat the shaft of the hair, allowing the hairs to slip past each other and giving the hair shine. The problem with silicone is it is very difficult to remove, and is only removable by sulfates, making shampoo and conditioner a cycle whereby if you use a silicone based conditioner, you have to use a sulfate based shampoo to remove it. This why you now see sulfate free products, because there are large movements (such as no poo) against using these products in your hair. 2-in-1 or 3-in-1 products are not going to give you the same results as using separate products. They will definitely not be able to adequately condition your hair and may be too harsh of a cleanser for your hair."
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5vp4sv | How could scientists confirm life exists on another planet "very soon"? | Technology | explainlikeimfive | {
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"If they detect certain gases in significant amounts (specifically methane and oxygen) this would be **very** suggestive of organic chemistry. These gases don't tend to stick around before turning into something else so their presence would suggest an active process that is creating them. There are some non-organic processes that can create them but these would usually be short lived or only produce small amounts. Organic chemistry produces them in large amounts here on earth however so if we see that happening somewhere else then it would be suggestive of earth-like organic chemistry."
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5vp5fh | Why do human ears have crevices and folds? | Biology | explainlikeimfive | {
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"The shape of the ears is probably important in allowing us to perceive the direction of a sound. We don't hear a sound until it arrives at the eardrum. To get there, it has to bounce around the folds in our ears and down the ear hole. High frequency (higher pitch) sounds, including things like s, t, k etc in speech, bounce off the folds in the ears in different ways. The brain can process the tiny differences in the arrival time of the different pitches so, even with one ear, we can roughly locate the direction of a sound. Add to that, we have two ears, they are not identical and the differences from one ear to the other also help. The [Wikipedia article]( URL_0 ) is not exactly easy reading. In fact, some of the scientific research articles are easier to read. Some of the early research is here URL_1 and here URL_2 Note that this work has been critiqued and refined. URL_3"
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5vp6o4 | if any of 7 newly discovered planets turn out to be habitable by humans, how would it impact the future of earth based on the fact that it's 40 light years away? | Other | explainlikeimfive | {
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"It wouldn't. Even if we decided 40 light years was am acceptable distance for humans to attempt to colonize. Current spacecraft can travel 17,500mph, the light travels 671 000 000mph. This means that it wouldn't take us 40 years to reach the planet, it would take us 1 533 714.2857 years. Longer than homo sapiens have existed. If we wanted to reach those planets, we would have to create a ship that can travel several hundred times faster than our current ships, and rig the ship with either some sort of preservation or else create a biodome for people to survive in. None of which is currently possible.",
"It's a hard question to answer because there are a lot of possibilities. We wouldn't try to colonize it for a long time; probably centuries. We simply don't have the technology for that yet. We would almost certainly send an unmanned probe there as soon as we could. Within the next few decades we'll have the ability to send a small probes to other stars at a large percentage of the speed of light, so we could conceivably send one towards this system at say 50% the speed of light. Of course that would take ~80 years to get there, and then another ~40 years for the information to get back to Earth.",
"Well yes, 40 ly is quite far. So the near future probably won't change that much. But we would probably focus on trying to build better ways to travel there instead of focusing on finding more habitable planets.",
"Gives us something to aim for. The proverbial carrot. At least one with of those planets has to be a paradise. Well im hoping. Picture the rivers, the oceans, huge forests teeming with giant horned monkeys."
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5vpbto | Why is it required to take blood tests in the morning? Even for night shift workers who only have time in the afternoon? | I'm a nightshift worker and mostly asleep during the required hours to take the lab tests. Are there studies that say its bad to take a blood test at night or afternoon? | Biology | explainlikeimfive | {
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"Fasting before the blood test is necessary so they do them in the mornings as you aren't eating at night and don't have to fast during the day. I have about as much knowledge on this as the average Joe but I'm assuming this is the reason",
"Those tests are based on your personal clock. Tests right after you wake up(fasting or otherwise) is standard and it takes out all the factors of what you did throughout the day. It's easier to compare these test results to reference ranges for whichever condition they are being drawn for. Your primary care physician and whomever is drawing you should know that you work nonstandard hours and draw your baseline tests when it's \"the morning\" for you. How I know this: I am a phlebotomist(I draw blood) and am a lab technician (I perform these blood tests). I've had to remind physicians and nurses about this before, sometimes they don't care sometimes it's an \"aha\" moment."
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5vpfsq | Say we were to colonise one of these planets. How would communication back to Earth work. Is there any possibility of faster than light communication or would everything we send between colonies take 40 years to get to one another? | Physics | explainlikeimfive | {
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"Communication would be limited to 40 year lag. Speed of light is an absolute max speed given our current understanding of science. Some people think that doing really tricky things with entangled particles could allow for faster than light communication. You can put information \"in\" to entangled particles and this change will be reflected instantaneously anywhere in the galaxy which is pretty cool. However it's impossible to get information \"out\" of an entangled particle. (Note even calling this \"information\" is misleading since it's not information if you can't read). So short answer: no we're limited to speed of light. Long answer: no we're limited to speed of light and quantum entanglement doesn't solve this but it's really cool check it out."
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5vphu7 | When someone is considered to be a "slow" person. | Edit: Mentally slow | Other | explainlikeimfive | {
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"I do this thing where i say \"what\" as if i can't hear what someone had said but then a few seconds after i realise what they've said and laugh. One day someone asked me why i always did that and i explained truthfully. The person then responded saying \"ohhhh you're just slow\" i guess you can be physically slow in speed terms and mentally slow correlating with how fast you react to things.",
"Consider: if you assume the first thing that comes to your mind when somebody says something, you are considered fast? So you are slow if you think of multiple things and take longer? I doubt it has to do with intelligence or retardation ."
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5vpqtn | If light doesn't move through time, why does light take time to go anywhere? | From my understanding of it, light travels at light speed, the speed traveling through space at which it stops traveling into the future. If light doesn't travel into the future, then wouldn't that mean that it would reach a location at the same time that it started somewhere else? Shouldn't it take 0 time for light to reach a new location, meaning its speed is infinite? | Physics | explainlikeimfive | {
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"To tackle this question, let's assume that light isn't the universal speed limit. (The speed limit being infinite). #We Know: It takes an exponentially increasing amount of energy to accelerate an object of mass x. Think of this as a 100m long ramp that grows steeper (as a function of mass) until it's completely vertical. **Ramp of Heavy Mass:** > & nbsp; & nbsp; & nbsp; & nbsp;| > & nbsp; & nbsp; & nbsp; & nbsp;| > _/ **Ramp of Small Mass:** > & nbsp; & nbsp; & nbsp; & nbsp; & nbsp; & nbsp; & nbsp; & nbsp; & nbsp; & nbsp; & nbsp; & nbsp; & nbsp; & nbsp; & nbsp;| > & nbsp; & nbsp; & nbsp; & nbsp; & nbsp; & nbsp; & nbsp; & nbsp; & nbsp; & nbsp;/ > & nbsp;__/ **Ramp of No Mass:** > & nbsp;__________ #We Conclude: 1. We can travel fastest on the ramp that is level rather than one that's uphill. 2. It is impossible to travel faster than the level ramp allows as negative mass and thus a negative declination cannot exist. 3. Therefore, When we have no mass, we travel the fastest. #Tying It Together **Fun Fact:** Light has a mass of 0! Thus using the logic from above, it is the fastest any thing can move on our \"ramp.\" Let's scale it down to easier to manage numbers. The speed of light is 299,792,458 m/s. Let's Say instead that the speed of light is 100 m/s, traveling the ramp in 1 second. > From my understanding of it, light travels at light speed, the speed traveling through space at which it stops traveling into the future. ###Defining The Future: In the above scenario, on one end of the ramp I have a flashlight. You are on the other end. Light has a mass of 0, and our \"speed limit\" we defined for that mass is 100 m/s. When I turn it on, you should see the light 1 second later. For time t(seconds) from **My Perspective:** > **t(0)** - Present > & nbsp; & nbsp; & nbsp; & nbsp;I Turn on the light. It begins shining towards you, hitting you at: > **t(1)** - Future > & nbsp; & nbsp; & nbsp; & nbsp;The light hits you 100m away. **Your Perspective** > **t(0)** - Past > & nbsp; & nbsp; & nbsp; & nbsp;It's dark. No light. > **t(1)** - Present > & nbsp; & nbsp; & nbsp; & nbsp;You see my light. So our \"speed limit\" (light) caused: 1. T= 0 to be both the Present and Past simultaneously. 2. T= 1 to be both the Future and Present simultaneously. > If light doesn't travel into the future, then wouldn't that mean that it would reach a location at the same time that it started somewhere else? Shouldn't it take 0 time for light to reach a new location, meaning its speed is infinite? Simple Contradiction Proof: Assume: Light has infinite speed causing it to not travel to the future. That Means: * t(0) Present: I turn on the light. * t(0) Present: The light hits you. The fact both of our times are t = 0 contradicts the **law** we defined above saying the fastest light moves is 100 m/s. So we need another time reference point 1 second later at t = 1. That would mean we have a \"future\". TL-DR; I took a ton of adderall to study for a test and did this instead.",
"This is part of how time is experienced differently by different observers. If you accelerate close to the speed of light, you experience less time than an observer in your original reference frame. Light itself experiences no time. (Because of Lorentz contraction, the universe appears to have been flattened to a pancake. Anything it's going to hit is right in front of it.) To outside observers light is traveling, well, at the speed of light.",
"It's speed is not infinite. In the point of view of an observer, it travels in the fastest possible speed. So it does move \"through time\". On the other hand, in the point of view of the photon, time slows down to a halt. A photon \"sees\" the beginning and the ending of the universe simultaneously.",
"By Metaphor: If I freeze you, you _experience_ no time. When I ship your frozen body cross-country, the fact that _you_ experience no time doesn't mean that the truck you are in doesn't take time to get there nor does it prevent me from drawing crude sentiments on your frozen face. So the packets of light which we most simply call photons, do not _experience_ time. That is if they had little minds those minds would not have any experience of existing. But the packet itself, with its wavy-ness and its particle-ness is moving and moving happens over time. If a person were in a ship and they passed through the entire universe at the speed of light. The whole universe would come and go unnoticed because their sense of our time would be zero. They would be the ultimate frozen corpse, utterly untouchable by us. But if we had sensitive enough instruments we could note their passing as disruptions of gravity or whatever, and that disruption would go past us at the speed of light, so we'd know they'd passed, but we could never know they they were about to arrive because their passage and the signal of their passage are going the same speed. So the old question: what happens if I'm driving a car at the speed of light and I turn on the headlights? If you are going _almost_ the speed of light then everything looks normal about you and the car, but the universe looks like a tiny speck right in front of you. If you are going the actual speed of light you never turn on the lights because you have slowed infinitely. You don't even know you've frozen. If you ever slow down somehow you'd never know that you touched \"light speed\"... except for the fact that the universe is now gone from around you.",
"The frame of reference for a photon or other object traveling at the speed of light is *undefined.* We cannot talk about the experiences of a photon or other such object because that frame of reference simply does not exist, it would violate a fairly central tenet of relativity. If there exists a rest frame at c, then there exists a rest frame in which objects *which move at c in every rest frame* are stationary, which is contradictory. Saying photons 'do not experience time' is actually going too far. Photons *have no perspective* from which we could even make that claim, or its opposite. None of this, however, means that an external observer cannot observe a photon pass through a finite amount of space *in the external observer's frame of reference* during a finite amount of the *observer's* time."
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5vptw8 | Why aren't high energy photons more massive than low energy photons? | Given that m=E/c^2, and therefore objects with higher energy have more mass than ones with lower energy (but the same parts), it seems logical to assume that a photon closer to Gamma Rays would have more mass than one closer to Infrared for example. Despite this, ALL photons are massless. Are photon's just special? | Physics | explainlikeimfive | {
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"E = mc^2 is only a shortened version of the full equation. The full equation is E^2 = m^2 c^4 + p^2 c^2, where m is the rest mass of the particle. A photon, by definition, **has no rest mass** i.e. m = 0. So it's equation for energy is E = pc. This means that higher energy photons have more momentum. Note that in relativity, something doesn't have to have mass for it to have momentum. EDIT: to add a bit more to your ideas about relativistic mass, we normally don't really speak of that in physics. We talk instead of the momentum increase of a moving particle and normally use mass only to refer to the rest mass (the mass an object has in the reference frame where it is stationary), which is unchanged across reference frames. Energy can look like mass from far away, however, and this is how most of the mass in the Universe arises - the energy of the strong force which holds quarks inside protons and neutrons looks like mass when you look at them from the outside. This binding energy is how the vast majority of the masses of protons and neutrons arises."
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5vpvoj | What actually happens when we shut a website down with the "Reddit hug of death"? | Technology | explainlikeimfive | {
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"The server that the website is hosted on is bombarded with too many requests at the same time for that website. A great analogy for this is a mail room. A mail works fine when there aren't that many people sending mail. But when lots of people try to send their mail at the same time, the whole system begins to slow down. Increase the size of the mail room, and it takes more mail to slow it down. But people will sometimes link to websites that have a small server, or 'mail room', and so it can't deal with the large amount of traffic - or mail - that is coming it's way."
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5vpz05 | How can websites like aliexpress offer their products so cheap with free shipping all over the world? | Economics | explainlikeimfive | {
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"Chinese government actually subsidy cost of shipping to support exporters, so that's why they can send you item you bought for 0.1$ with free shipping. Longer explanation would be that they ship in bulk with pay per volume and not per item, so they don't care it's actually one small item for one customer, but anyway it's subsidised by Chinese government.",
"Because products are cheap. Take clothing. Manufacture of clothing is cheap. Any synthetic fabric used, was discovered as a new cheap plastic that could be turned to thread. The difference in price is because they ask and they receive. Any other plastic item, when mass produced will be worth marginally more than its weight in oil. So you're left with metal and wooden objects that might be Actually Expensive. So a lot can be saved there. The shipping is really the most costly part. Idk about your example in particular, but there is one online store in China, that the way their shipments come in, I think they put batches of their stuff on ships that are already sailing the same direction as their items, get a discounted rate for not taking up a lot of space, and for ensuring the owner of the boat that they (boat owner) will have maximised their freight this trip. Something like how online air fare sites were supposed to do until they obviously hand shaked once too many with the hotels and all"
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5vq0hg | If an American citizen shot a Mexican citizen from across the border fence, what would happen? | Other | explainlikeimfive | {
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"It's not an act of war if a private citizen kill another private citizen, regardless of where. It is a crime, and the criminal will be tried where they were at the time of doing it, regardless of the victim being over the border. The definition of \"murder\" in the USA requires no reference to the location of the victim.",
"This has happened before: URL_0 The guy was charged with 2nd degree murder in America and sentenced to prison in America."
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5vq11h | Why are other drinks not as effective in hydrating as water when they have water in them anyway? | Biology | explainlikeimfive | {
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"In fact most drinks are about as hydrating as water. But some drinks contain a *diuretic* ingredient -- something that causes your body to throw out a bit of water -- such as caffeine. So these are not quite as effective, though (contrary to myth) they still hydrate you.",
"Some contain caffeine which is a diuretic, makes you pee more so you lose water. But mostly they work pretty well for hydrating, some work better than water because if you're sweating a lot and losing water and salt taking in just water isn't as useful because the body has to maintain specific levels of electrolytes. By the same token if you have too much of those electrolytes because you don't have enough water to dilute them drinking things stuff with salts in it will be a bit less effective. Last of all a lot of sugars like in fruit juices and sodas can make diarrhea worse, and diarrhea is a thing that causes a lot of dehydration. So there are a lot of things at play, but for hydrating generally water just works best because you're not getting other stuff that may cause complications to keeping the water in and getting the benefits."
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5vq5l8 | How does a slot machine choose a winner? | Other | explainlikeimfive | {
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"Software developer here, I wrote Class III casino slot machine software for 5 years. These machines are, by law and by definition, truly random. They use a hardware random number generator (RNG) to produce values that determine the outcome. The RNG is a \"noisy diode\", an electrical component, a semi-conductor. Diodes consist of a PN junction, where each side is biased with a surplus or a deficit of electrons. The N side has lots of electrons and doesn't want to take on any more, the P side has the deficit and wants to fill the voids. So electricity prefers to flow in one direction and not the other, it's an electrical one way valve. By introducing a contaminant conductive metal in the middle, you get a circuit that when ran in reverse, resisting the flow of electricity, will spontaneously close the circuit and conduct, the circuit flickers. It's a relatively simple matter, then, to sample the circuit at some maximum rate - you have to give the circuit some time to transition between on and off, and it's at MHz speed so it's very fast, these things are integrated inside microprocessors. The first thing the game does is store the random number. The game is required to recover completely if interrupted, say, after power loss, and either pick up *exactly* where it left off or start the exact same sequence all over again. The whole sequence, from one \"spin\" to the next, including the bonus rounds and pickem mini-games, are all pre-determined. That's right, the bonus games? All entirely predetermined. > \"But mredding, that can't be true! What about the mini games where I get to pick a reveal?\" I hear you. Now hear me: this is called The Illusion of Choice. Whatever you pick we, reveal your predetermined result under that pick. It doesn't matter what you pick. The game is, by law, *NOT* a game of skill, and \"picking the pooper\" as we used to call it is considered a game of skill. It's a video game, there are no actual physical cups before you, one with a bean hidden under it. Hell, even if there were physical cups, any magician worth his salt could palm the outcome to any cup he wanted. Ever play 3 Card Monty? Same thing. There is some math involved. The reels are really a math table in a config file that describes a distribution - some results are more likely to come up than others. The casino can set the odds on the machine before hand. By law, they are not allowed to change the results without your knowledge, aka during play. So there's no mastermind behind the scenes pulling secret levers to skew the odds on you. They have to physically key the machine to access the configuration panel to choose the odds they want. So yes, some machines along a bank might have more favorable odds than others, just to attract people to the bank. They choose by percent payout, that statistically, for every dollar that goes in, the player gets X% back, between $0.98 and $0.84 back. Caesar's casinos are by far the worst. They run their games with the lowest odds. My previous employer didn't make such shitty odds even an option until Caesar's said they wouldn't buy our machines without that option. And here's the thing about odds, they're random, they're not gospel. The odds designed for one of our games suggested it would pay out its jackpot once every 6 months. They would win and lose all the time, that's normal gameplay, but the jackpot, the big win, one machine somewhere on Earth *should* hit every 6 months. We put that game into market, world wide, and two machines hit within the first month. There's no guarantee, nothing is fixed, nothing is promised, it really is random, just unlikely. Past events do not determine future outcomes. Unlikely things can and do happen all the time. There was a slot machine at the MGM, Lion's Share, that hadn't hit its jackpot for 20 years. There was absolutely nothing special about that machine, there were dozens of others like it, probably hundreds of others like it when it was first released, yet this one held out for 20 years. And Vegas law says a machine can't be pulled from the floor until it hits it's jackpot, which is why it was there the whole time. MGM had hated that machine and wanted it the fuck off their floor that whole time. Edit: And you can't influence the outcome. The machine doesn't care how you push the buttons or pull the lever or touch the screen or whether or not you use your player tracking card. If you can influence the machine, that's a game of skill, and that would be illegal. The regulators wouldn't come down on the casinos like a mother fucker, they would come down on the manufacturer for making their games illegally skill based. So pick your betting strategy and play the game, don't waste your time looking like an idiot trying to touch the screen in certain magical ways that you think is doing anything. Really, we who were or are in the manufacturing side of this business, and I suspect the casino operators as well, those of us who know, find you people *hilarious*. And the manufactures do surveys to try to understand this behavior better so *they can take advantage of it* in ways to influence you into *playing more*. These games are psychological warfare. They want you addicted, but they *say* they don't want you addicted.",
"I like slot machines. they're mindless fun, and I like the bright lights and noises and the fun bonuses. I knew they were random (I worked in the UK with fixed odds betting terminals and those are broadly the same) but it's hard if you're a player putting in $20 bills one after the other with no apparent chance of winning. I can see that at that point you could convince yourself that the machine is 'trying' to stiff you. *Slot machines don't choose a winner.* Each machine has a prefixed chance of selecting a winner. It does this by generating a random number, and it's that random number that determines your prize. So, let's say the number that's generated in 0.3495783171. Good News! That's a winning one! So then the on board computer renders that win for you - usually in a way to make it seem a bit more entertaining. The same thing applies for a bonus. You ever get a bonus game where you're *this* close to a huge prize? That's done after the RNG is selected. That's where the psychology comes in. Ok, you've already won $50, but the research shows that if you're convinced you **nearly** won $50,000, you're more likely to come back. There's a lot of really interesting psychology in slot machines - years ago you used to have 3 reels and one payline (very simple) but they figured out that if you have a $3 play and you get back $1 \"winnings\", that was more likely to encourage people to play than a $2 machine that you lost all of that stake the majority of the time - even though it's pretty much the same. I always go for the max bet (although generally sticking to machines that are no more than $4 a spin) just because I at least want to believe I have a chance, however small to win the progressive jackpot. [edit - as I say this I realise that /u/mredding covered the technical side of it really well. So I spent 10 minutes writing a post to essentially say \"herp de derp, I like slot machines\"]"
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5vq8j3 | What's in the space between gas particles | Prompted by me trying to explain to myself why wind is "invisible" - did a search and it says air is invisible because gas allow light to pass through it, because it's particles are so far apart. And then I got to the question above. Halp | Physics | explainlikeimfive | {
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"There is empty space between them. Except empty space is [not]( URL_0 ) empty. tl;dr There's a buch of quantum stuff in there. Now what is in between the quantum stuff?",
"Okay... So it's hard to wave your hand through solid rock because the rock is in the way. So it's easier to wave your hand through a liquid because the liquid is in the way but it can be forced out of the way. So it's easier still to wave your hand through a gas because the gas is in the way, but it can be _both_ moved out of the way _and_ crushed/compressed. The \"compressed\" thing is possible because the space between the molecules is effectively empty of everything except... Well, see, matter isn't just little bits of stuff. It's little bits of stuff that _claims_ the space around it using things like charge and gravity and stuff. So grab a couple magnets. Each magnet has a defined size. But the magnets \"claim\" space around them with their magnetic fields. If the space is claimed in some patterns the magnets will be drawn together. In other arrangements the magnets are pushed apart. Now... light is very, very small. The photons are good at just not hitting stuff. So the particles of gas are bouncing around and the light is going trough that same space. But most of the time the spot the light is more-or-less \"in\", doesn't happen to have \"stuff\" in it. And slightly less of the time does the space have the \"claim\" in it. So light passing through a gas gets mostly free passage. It scatters a little bit maybe because of very rare interractions with the stuff the gas is made of. Then there are some gasses, like chlorine gas, that have a unique color. They are good at messing wiht photons because their are made of fairly large molecules made of fairly large atoms. So chlorine gas is yellow because it tends to catch the low-end reds and blah blah blah. But when we go up to liquids they tend to be more densly packed. All the molecules are, at a minimum, touching eachother at least a little. So liquids are a harder thing for the light to get through. So liquids tend to scatter and absorb more light. So it's easy to see light a mile away in air, but not so much in water. Then we get to solids, like rock. Not only are the pieces touching, they are locked together. They are solid. It doesn't take much solid stuff to make sure that the photons have to interact with at least some of that \"stuff\". So something as thin as a sheet of paper can easily be assured of blocking \"most of\" most normal amounts of light. What is blocked becomes heat. So there are literally photographic flash devices for cameras that will instantly incinerate a sheet of newspaper just by brightness alone. So then we have glass and that sort of thing. Sold things that light _can_ pass through. See each chunk of light has properties like frequency and energy. And solid lumps of things also have properties like energy. So it happens that the energy of a solid thing can be compatible with letting light of some, or many, frequencies pass through. This is because of the way all the little bits of stuff claim their space. For instance if you have two magnets pushing against each other you can still pass a piece of paper through the gap between them because magnets don't affect paper. Same with a little piece of aluminum from like a can. I the frequencies and other claims that something make on a space don't _interfere_ with the claims that something else makes they are more-or-less immune to each other. Try to slip a steel paperclip between the magnets and it's probably gong to stick to one or the other. So lets go back to aluminium. As a metal it's opaque. Like if I just melt it into a blob and then cool it off it's shiny and you can't see through it. If I crush it while it's melted I can make a ruby that lets red light through. If I crush it harder it might be a blue or green sapphire. If I crush it really, really hard it becomes \"clear\" sapphire. In an almost criminal act of over-simplification -- This is because the aluminum atoms end up dealing with each other in a way that can just pass the photons on instead of stopping them and turning them into heat. Now there's a whole bunch of quantum mechanical stuff involved in solids passing light around. \"Photons\" become \"phonons\" and there's wave phases and all sorts of heavy math bullshit that I can't really describe well enough to satisfy the real science... But all that being said, some of that whole frequency, phonon, quantum stuff is _actually_ happening in the gas as well. So some of the gasses in the air, should they be hit by a photon, will pass that photon on unchanged. Like it's a weak hit. Like, the individual gas molecule is just like a larger solid that happens to be transparent. So \"the wind is invisible\" is a very, very simple explanation. And it's \"mostly true\", but with heat and pressure we can get \"heat distortion\" and \"mirage\" effects where it looks like there is water on the ground but it's just the air reflecting and refracting light. So the same \"nothing\" that's between the gas molecules here on earth is the same \"nothing\" that's between the random tidbits that are floating in space. It's literally nothing. \"no\" \"thing\". But we loop back to the somethings that claim spaces bigger than the thing itself. So now we contemplate \"nothing. If the proton in the center of a hydrogen atom were as big as a baseball, and I put it in the center of a football stadium, then the electon would be the size of a sweet pea and it would be \"somewhere in the cheap seats\". But the baseball-sized proton is \"claiming enough space\" to cover the stadium and it's parking lot. That's a lot of nothing. If I make the proton the size of a soccer ball (and the electron is the size of baseball now), then put one in the center of Century Link Field in Seattle, and another one in the center of Safeco Filed \"right next door\" that's a pretty good estimation of a single molecule of H2 (hydrogen gas) The next nerest molecule of H2 is on the other side of the city, on average. And a photon is, at this scale, the size of a grape, and all it has to do is not hit either soccer ball or ether baseball in the stands. That's a _lot_ of nothing by volume. But like any trip to the ball-filed on game day the grape may need to squeeze through the quantum uncertianty of all the people doing things because of the game. We cant guess where the people are going to be, we don't know if they are going to the game or just trying to park or whatever, so the grape needs to \"dodge\" whatever people might be around. The people are the momentary quantum effects and any one is easy to dodge but taken as a whole they aren't more than a minor hassle. So ... TL;DR :: There's nothing but the _chance_ of meeting something quantum in the space around the atoms of anything, and the more those atoms are bouncing around the smaller that chance becomes, and gasses bounce _a_ _lot_... so the light is virtually certain to get through with minimal inconvenience.",
"There are 2 different thing to consider: the density of the gas and the molecular composition of the gas. The density is measured by the number (and size, possibly) of molecules in a certain volume. The part of that volume which is not occupied by the gas molecules is vacuum, like in space. Barring quantum effects, which are unnoticeable to our eyes, vacuum lets light pass through it uninterrupted whatsoever (the speed of light is greatest in vacuum). So the less dense the gas the less you will see it (if you could see it at all, continue reading). The molecular composition determines what wavelengths of light (visible or not-visible) the gas will interact with. Remember that to see something, that something must reflect light, otherwise it's transparent. Oxygen and Nitrogen molecules, the main ingredients of air, do not interact with visible light, so we don't see them, no matter how dense they are. Iodine in gaseous form looks purple because its molecules interact with the purple wavelength. Just to cover more bases, glass, while transparent to visible light, can block ultraviolet light, but our eyes don't see this. There is no strict rule on what material reflects what wavelength. One very important application of this property of molecules is *spectroscopy*. We can study materials by shining them with various wavelengths and see which are reflected, absorbed, or transmitted. This allows a method of identification of materials."
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5vq9vo | How interruptive are the effects of Wireless and Electromagnetic waves on living organisms? | I recently had the wild realization that for the most part, the vast majority of the population lives in neighborhoods and houses surrounded to the brim with Power-lines and loads of gadgets inside. Are living organisms (such as forests or animals) affected by these waves and if so what exactly is happening? Have there been any experiments to show that Wi-Fi hampers plant growth? | Technology | explainlikeimfive | {
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"It's important to realize even without gadgets, powerlines, and wi-fi, you are *still* and *always* being bombarded by electromagnetic waves. Essentially every object in the universe is emitting electromagnetic radiation, including you, rocks, televisions, air molecules, toilets, corn (both harvested and unharvested), and Rex, your dog. 'Wireless' is simply a part of this spectrum, not some other thing. This radiation is the non-ionizing kind. It can cause heating when absorbed, and if an organism absorbs enough (like grabbing hold of a radar or putting yourself in a microwave) cause burn damage."
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5vqep2 | How does the brain decide what little stupid things to remember, like what someone said or a song you heard once? | Biology | explainlikeimfive | {
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"it's mostly based on the situation you're in. even if you just barely notice a balloon in the furthest corner of your view your brain could go like 'you member the time, you had that stupid little baby balloon? i member'"
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5vqm8a | How do they synchronize the sound so perfectly with images in complex musical movie scenes such as the last 11 minutes of whiplash ? | I mean, they must've shot so many takes of that scene, probably on several days, but after the final montage, the sound, the music, the images, all fit together near perfection. | Other | explainlikeimfive | {
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"It depends on the type of music and the level of synchronization needed. I assume you are talking about very accurate synchronization and not just background music that doesn't need to be aligned with specific events on screen. If the music is electronic, it's just a matter of aligning the music track with the video track. Electronic music can be altered or tailored to fit the visuals exactly. If the music requires live players and a conductor as in orchestral music, one technique is to screen the visuals to the conductor via a screen located behind the orchestra. This allows the conductor to react in real time to the visuals (and the players to the conductor). One of the hardest synchronizations is actually found mostly in cartoons, where the orchestra is tasked with sound effects or otherwise with direct reaction to what's on screen. Ever seen the Loony Toons \"musicals\" like \"Kill the Wabbit\"? The instruments need to react to the footsteps of the character, for example. Or \"Bugs Bunny Opera\" where the orchestra and conductor actually need to react to a mirror image of themselves. This kind of synchronization needs to be very precise because orchestral sound does not tolerate too much post manipulation.",
"It is possible to play back the video and music at different times to try to match them up. And you pick your cuts for the same effect. You can also subtly change the playback speed of the video to further make it match up to the music. And as you mentioned they have multiple takes and can take the take that best fits the rhythm of the music. They often play the music on the set to help the actors with the rhythm.",
"I don't know the movie you're talking about, and so I don't know how old or new it might be. But I am a musician who plays on the soundtracks for many video games and movie scores and can speak about the way it's done now. In scenes where the music is just \"background\" and doesn't have to match up with specific events you can be a bit more lax about the process, but if you need the music to match up exactly here's how they do it: Composer gets a final copy of the video. It's all timed and cut the exact way it'll appear in the film. The composer will make a note of important actions in the film and exactly how far apart they are (e.g.: the two swords hit each other at 1:42.556 and 1:45.637). Then they will come up with a musical idea or melody that would fit the action and they'll do some math to find out exactly how fast the music needs to be so that the two big orchestra hits happen exactly at those times. A lot of times this means that the music will be at an oddly specific tempo, like MM 135.8. Then they write the music at that tempo so the two big chords happen exactly in line with the film. Next they go into recording with the orchestra. The orchestra all have headsets on with a \"click track\" going. The click track is programmed to click at exactly 135.8 beats per minute so it will be the exact tempo needed to fit the action on screen. Then they record the piece and it's perfectly synced with the action due to the musicians all hearing the click in their ears and playing at the right tempo to match what's happening on screen."
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5vqrnl | How can I see the moon in day time while also countries in night time around the globe see it too? | Other | explainlikeimfive | {
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"half of the world can see the moon at any point in time. and half of the world can see the sun. Of course those 2 halves can overlap some, all (solar eclipse), or none (lunar eclipse). so at 10PM EST/6PMPST, if the moon is somewhere over north america, both coasts can see the moon, but only the west coast will still be able to see the sun."
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5vqsbv | What makes hot water so special that it "cooks" a lot of instant food? | Chemistry | explainlikeimfive | {
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"typically a lot of these types of food are already cooked and just need to be warmed, or more often re-hydrated. warm water is absorbed faster and thus it re-hydrates the food quicker. (as well as warming it)",
"In addition to what /u/Lokotor said, I'll add this: Hot water is a source of heat. In fact, boiling water in particular is a source of heat with a very specific temperature, which makes cooking times very predictable. Adding boiling water to instant foods serves the purpose of hydrating them, yes, but also of cooking them at a very specific temperature, which means that the directions can just be \"pour in boiling water and let sit X minutes.\""
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5vqtuk | Jesus saves, but only Buddha makes incremental backups. | I saw this on another reddit thread just now, amused me... and then I realized upon reflection that I really don't fully understand what it means. Upon googling, a handful of results popped up, so it's apparently a thing. Not an overly popular thing, but a thing. Anyone care to explain? I feel like it has something to do with reincarnation maybe but can't nail the analogy exactly. | Other | explainlikeimfive | {
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"> Anyone care to explain? I feel like it has something to do with reincarnation maybe but can't nail the analogy exactly. Saving is storing a file on a permanent storage medium such as the hard drive as opposed to active memory which goes away if the computer loses power. Jesus is supposed to give people eternal life with one pledge. Incremental backups store one record of everything at a given point in time, then later checks to see what has changed and stores only those things which have changed. Buddhists believe that people live many lives over and over, their position in later lives dependent upon how they lived their previous lives. The analogy is a little tortured but it is there enough to be funny.",
"There are more than a few \"Jesus Saves, _______\" jokes out there. They are more about using the format in a clever way than making profound statements, so don't try to read too much into it. In this cases, there is a vague analogy to reincarnation. In Buddhism, your spirit is reincarnated, learning in each life, until your reach enlightenment and enter a state of Nirvana. No matter what you do, you come back in the next life, which is kind of like an incremental backup. Contrast this with Christianity, where if you screw up once, you die and go to hell for all eternity. Very much like not having a backup."
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5vquep | What cause people to be introvert/extrovert? | Other | explainlikeimfive | {
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"One of the leading theories deals with whether or not someone \"prefers\" the dopamine-heavy sympathetic or the acetylcholine-heavy parasympathetic nervous system. Dopamine being the reward center seems to be focused on outward gratification, while it's widely accepted that acetylcholine is focused on looking inward and receiving serenity and pleasure from doing so. I'll update this in a bit with a link to the article I read, but I've gotta find it. edit: URL_2 URL_0 Here's a journal talking about sympathetic transmitters in guinea pigs: URL_1",
"I 100% agree that the introvert/extrovert meme is way out of proportion. I think part of the problem is that introversion has become a way to talk about shyness (normal in some situations, but perhaps an issue in regards to self-confidence and social skills at the more extreme end) to social anxiety disorder (a mental illness). Humans are fundamentally social. Some people need a lot of social engagement, some people need relatively less social engagement, but social support and social connections are *a determinant of health*. As in, people with fewer reliable sources of support generally have poorer health across many different dimensions. Netflix isn't a substitute for social support. All of the crap on Buzzfeed is not a substitute for social support. It annoys me to no end that it's \"trendy\" to be an \"introvert\" because it's not just based on shit pop science, it is legitimately harmful to normalize social isolation. End rant."
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5vqv8p | How is lying protected (or not) under the 1st Amendment of the U.S. Constitution? | Other | explainlikeimfive | {
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"It's unconstitutional to ban lying on its own and there was even a recent case about it. In 2005 Congress passed the Stolen Valor Act, which made it a crime to lie about receiving military honors. In 2007, a guy introduced himself at a meeting for his water district board by saying he had a medal of honor, which was false. He was charged under the act, but he Supreme Court held that the law was unconstitutional since it violated the First Amendment. That doesn't mean lying is always protected, though. It can be a crime to lie under oath in a court proceeding, to commit fraud, to lie to government officers, etc. The big difference between these lies and other lies is that with these lies you know someone is specifically relying on your information to undertake some action. The Court likes to draw the difference between you telling someone at the bar \"Oh yeah, I'm the biggest badass around\" and you falsely telling a potential consumer \"This car is great and has never been in a wreck.\" Lying can also get you sued civilly for fraud or defamation/libel, though you have to do more than just lie for those. For fraud, you once again have to know someone is relying on your lies. For defamation/libel, you have to tell a lie that damages someone's reputation (and often that the damage caused the monetary loss). As for fake news, it's hard to say how that would play out, but it's probably protected by the First Amendment. If it's bias, spin, or an innocent mistake in reporting, then it should be protected by the First Amendment. If a news station presents demonstrably false facts as true again and again, you could argue that they knew their viewers were relying on those facts or that they were trying to lure people in with lies presented as truth. That would be a very hard case to make, though, and would depend on the facts. Reporting something like \"drinking arsenic won't hurt you\" is clearly a little different than \"Trump inauguration is biggest ever.\"",
"Libel is a civil classification, not a criminal one. The Government will not punish you in any capacity for it with prison time, or any other penalty. A private citizen who you've damaged due to your lying actions can sue you in civil court, but their has to be some demonstration of monetary damage done to you. Criminally, you can't lie under oath. That is felony perjury."
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5vqye0 | How did old games and computers display large numbers? | For instance, the NES was 8-bit, and 8-bit integers can only be between 0-255. Yet the score (in say Super Mario Brothers) can be into the hundreds of thousands, something even a 16-bit integer can't handle. Pac-Man also let you score up to over 3 million even though the level counter would break at level 256. | Technology | explainlikeimfive | {
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"The same way you write and do math with numbers larger than 9 despite the fact the only digits you have to work with are 0-9, you chain them together. 8-bit microprocessors are designed with instructions that make doing operations with data made up of multiple bytes easy. So for example the \"add\" instruction included a 'carry' flag, so if you had two 16-bit numbers X2-X1 and Y2-Y1 (where X2, X1, Y2, Y1 all are 8-bit numbers) added X1+Y1 and got something larger than 255 it would set the carry flag. Then when you added X2+Y2 the processor would add +1 if the carry flag was set. This means you just need to iterate your add/subtract/whatever instruction through the 8-bit numbers that make up your 16-bit (or 32-bit, or whatever) number. Like I suggested at the beginning, this the same approach you probably take to doing most math. Do the 'ones digits', do the 'tens' digits, do the 'hundreds' digits...etc.",
"When a system is 8 bit that means that the processor can only handle 8 bits at a time. However it is possible to calculate with bigger number by breaking it into multiple smaller numbers. Just like an 8 bit computer can only deal with numbers between 0 and 255 humans can only deal with numbers between 0 and 10. However if I gave you 3890+4978 you would be able to calculate it by adding one digit from each number at a time. A processor have the same capability so it can in theory do maths on numbers as big as the machine have room for. However limiting the space available for each number to a fixed size makes the coding much simpler.",
"In the same way modern computers do it: by storing large numbers in several consecutive bytes in memory. The only difference is that modern CPUs have instructions to perform arithmetic with large numbers natively. Older CPUs didn't, so we have to perform those operations by running a short software routine. As an example, the Z80 CPU can add/subtract 16-bit numbers. If you need to, for example, add two 32-bit numbers you would start by adding the two low words using the ADD instruction. If the result doesn't fit in 16 bits then a 1-bit flag inside the CPU (called C for \"carry\") turns on. Next you add the two high words using the ADC instruction, which adds up two values and the C flag. If you have a larger number (56-bit, 64-bit, 4096-bit...) then you just keep adding each pair of words using ADC. Source: I grew up using MSX computers and still use them today. I've done my fair share of programming in Z80 assembler.",
"Just split it up into several bytes. 255 255 255 gives you quite a high score. Sometimes it's just that simple :)"
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5vr15v | How do Bluetooth IEMS/Headphones actually transmit sound without any physical connection between the IEM and device it is paired with? | Technology | explainlikeimfive | {
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"The sound is converted into a radio wave and broadcast to the receiver, which then receives the waves and converts them back into data. This data could be sound, or it could be any other kind of data you'd like to send. Anything and everything \"wireless\" works in this way. What makes Bluetooth different from FM radio is the frequency it uses, and the way it encodes data. Bluetooth uses a much higher frequency than your car radio, which means it has a much shorter effective range, but also means it can send more data at once."
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5vr4fb | Why does electricity heat things up? | Physics | explainlikeimfive | {
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"Due to the wires having electrical resistance, which means that they resist the motion of electrons, the electrons bump into atoms of the wire, and some of their kinetic energy is given to the atoms as thermal energy. This thermal energy causes the wire to heat up.",
"Things are made of atoms. Atoms have nuclei, positively charged clumps of protons and neutrons, and electrons which go around the outside. When electricity flows, electrons are actually moving from one atom to the next. As electrons flow, they can bump into the nuclei. Kind of like rubbing your hands together makes your hands warm from friction. Electrons rubbing along nuclei makes the nuclei warm. There is a much more accurate and in depth explanation, called Quantum Free Electron Theory. I won't go into it here, because it's a recent topic in my lectures and I don't fully understand it enough myself to explain it to someone else.",
"It would technically be more accurate to say *current* heats things up. Current refers to the *movement* of electrical charge carriers (electrons in most cases) however, this is probably what you meant when your said \"electricity\" anyway. So to answer your question: Friction. Like I said above, current is the movement of charged particles. Imagine a large vertical pipe filled with big rocks. Now imagine dumping a big bucket of sand through that pipe. Since the rocks are big and oddly shaped, there are a bunch of spaces between them that the sand can fall all the way through. Each grain of sand is like an electron flowing through a wire (pipe) while periodically bumping into copper atoms (rocks) along the way (although electrons typically move much slower than the sand would in this analogy, but I digress). This bumping is what's important. Each time an electron bumps into a copper atom, it loses a tiny fraction of its energy as heat due to friction. This is the same concept as why your hands heat up when you rub them together really fast. So if you imagine billions of these collisions happening every second in just a short section of wire, you can see how things would heat up pretty quickly. There are of course many other factors at play here, one of the most prevalent being resistivity. Certain materials heat up more than other because they have a higher resistance. Imagine the pipe from earlier filled with even more, smaller rocks so that the sand can't flow as easily (note: this is not a proper analogy for resistance. Materials with a higher resistance do not necessarily have smaller atoms than a material with a lower resistance). \"But wait!\" You might say. \"What about rubber? It has a really really high resistance, but it doesn't heat up at all when I put my 9V battery on it! Doesn't that go against what you just said?!\" Well, yes and no. Rubber is an insulator, meaning it's resistance is so high, it usually will not conduct a *current.* Remember when I said current was the movement of electrons? Well if electrons aren't moving, they won't bump into anything. If there's no bumping, there's no friction. If there's no friction, there's no heat. Now, theoretically, with a large enough voltage it would be possible to get a current flowing in a sample of rubber. However, this voltage would be astronomical and you would almost certainly hurt yourself and others around you, if not with electricity then with the ensuing fire you just started. Be careful! **TL;DR**: friction. Source: Computer engineering student."
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5vr4ko | Why do city lights appear to be twinkling when viewed from high up? | Was on a plane landing at night and all the lights appear to be twinkling slightly. I know they can't all be blinking, so why is this? | Physics | explainlikeimfive | {
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"Once you get a certain distance from those lights, they become so small they are essentially just points. When light from that point travels through air of a different temperature, it bends, causing it to twinkle. Also, some of those lights are shining through obstructions, like tree leaves. As the leaves move in the wind, they will hide and reveal the lights behind them.",
"It is for the same reasons that stars appear to twinkle. The Earth's atmosphere, other things in the atmosphere, obstructions etc.",
"Depending on how high up, it could be variations in the atmosphere that cause the light to appear to twinkle. The varying refraction can cause the direction of the light to vary, causing the apparent twinkling."
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5vr6s9 | If a paraplegic has no sense of feeling or temperature in their lower extremities, how is their internal body temp regulated on their lower half? | Biology | explainlikeimfive | {
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"It isn't. You need to be very careful about getting too warm or cold, and manually maintain temperature with adding or removing clothing, ice packs or heated blankets. This is more an issue for quadriplegics which might not be able to sweat very much at all."
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5vr6xm | How do headphones work? | Technology | explainlikeimfive | {
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"Pretty basic. The audio plug is called a TRS (or TRRS, it depends). The connector has three leads: \"left\" and \"right\" voltage signal and ground. You can see this for yourself by counting the number of sections on each audio plug (the sections are divided by bands). The two \"positive\" leads (the left and right signals) run to the left and right audio speakers, which are in your headphones. The speakers convert the electrical signal into vibration, which is sound. I have taken apart many audio cables before, but I can never recall the proper order of TRS plugs. I think that the first section, which is the tip of the plug, is the lead for the LEFT SPEAKER and the second section (the \"ring\") is the RIGHT SPEAKER lead, which leaves the final one (the \"sleeve\") as GROUND. See this diagram: URL_0 For TRRS audio plugs, there is an additional section to fit a microphone lead also.",
"In addition to what /u/lonesentinel19 said, a headphone works like a speaker. In a ridiculously simplified explanation: A fabric cone is glued onto a magnet, and a wire passes over the magnet. As electricity is passed through the wire, it generates a magnetic field which moves the magnet by attracting or repelling it, which moves the cone thats glued to it, which moves the air around your ear, which is what sound is. Microphones work in the reverse, you blow into a fabric cone attached to a magnet that moves up and down and generates electrical current in a wire, which travels through a cable to your speaker wire, which moves a magnet attached to your speaker cone which moves air around you generating sound. Electromagnetism is beautiful."
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5vr785 | What do soldiers of peaceful countries do in their average day? | Other | explainlikeimfive | {
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"The soldiers do whatever any soldier does when not deployed. Training, exercises, equipment checks, more training, guarding critical areas, more exercises, etc. However the service time is usually shorter then a more active military. Instead of having a big part of the able men in the nation on standby all the time people are sent though boot camp and training and then are discharged. If there is a need for a military you have a lot of young people who have completed military training that you just need to equip. You might even have a big part of the civilian population already assigned to units and be equipped (including assault rifles) in the event of a sudden attack. They will not be as good as a fully trained army but can do fairly decent, especially if they are given warning of a potential threat so they have time to get in shape.",
"> I'm talking like the Scandinavian countries that are peaceful as shit. URL_1 URL_0 Just because they're not fighting eachother doesn't mean the soldiers aren't doing anything. If a country isnt using its military and doesn't have a global network like the big spenders, most are generally on call/reserve and expected to keep up training incase they are needed. This is Esp. true for Switzerland."
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5vra5s | The game of cricket, and how/why can the games go on for days | As an American I've always been curious, but without any media coverage it's hard to understand both the rules and gameplay. Especially how games can have such huge scores and go on for such long times. | Other | explainlikeimfive | {
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"The basic idea is similar to baseball, softball, rounders, and so on. One team bats and tries to score runs, the other bowls and fields and tries to get the batters 'out'. Cricket games owe their length to one simple aspect of the rules: *the batsman doesn't have to run*. They can face ball after ball from the bowler, just defending and making sure they're not put out, and waiting for the opportunity to make a great shot. Combined with the batsman using a wide flat bat that gives them more control than the round bat used in baseball, a batsman can stay in for a long time. In the long form of cricket each team bats twice and they keep batting until all but one batsman is out and can take four or five days. (In fact if the team batting last still has two or more batsmen in when the last day finishes, the match is a draw no matter what the runs scored are.) 'Limited overs' cricket matches are shorter and have become popular, such as one-day (matches last, dur, one-day) and Twenty20 (matches last about 3 hours). These all work by limiting the number of balls bowled in an inning(s), rather than playing until all batsmen are out. (An 'over' is six balls bowled).",
"You are talking about \"test match\" cricket. Which is the longest kind. They have one day cricket and 20-20 cricket which is more like the length of a sport we are more familiar with. In test match cricket each batter stays up until the other team takes their wicket. That is a little piece of wood balanced on some sticks. If the batter is in his box they can't go after his wicket from the field. Kind of like how you have to strike out a batter in baseball and you can't just tag him out. In cricket the bowler (pitcher) throws the ball at the wicket and tries to knock it off. The batter primarily tries to protect his wicket and only goes for runs on favorable pitches/bowls. Just like in baseball it is a complex strategic battle between batter and bowler. Think of it like a batter in baseball fouling off pitches he doesn't like, but for much longer. That makes the game long.",
"To add to that - in the past, in England, a cricket match would be part of a social gathering as much as a sport, for example between villages in Yorkshire. Spectators wouldn't always sit and Watch the match non-stop as an event in its own right; they'd be doing other things, wandering in and out, getting drunk, and generally using it as an excuse to socialise.",
"You have two sides, one out in the field and one in. Each man that’s in the side that’s in goes out, and when he’s out he comes in and the next man goes in until he’s out. When they are all out, the side that’s out comes in and the side that’s been in goes out and tries to get those coming in, out. Sometimes you get men still in and not out. When a man goes out to go in, the men who are out try to get him out, and when he is out he goes in and the next man in goes out and goes in. There are two men called umpires who stay out all the time and they decide when the men who are in are out. When both sides have been in and all the men have out, and both sides have been out twice after all the men have been in, including those who are not out, that is the end of the game!",
"I think everyone else have explained the rules in general. I will try an explain the \"games go on for days\" part. So cricket unlike most sports has 3 different formats: First the Test format, the oldest form of the game, looked as the \"premier\" format by most players and hardcore fans, this is the format that goes on for days (5 days is the maximum, can end earlier). The reason people consider this the premier format is the skill level required to play this format is different to the other formats, each format having its own challenges, but time being also another factor it means it adds another dimension to your game and requires you to have more endurance as well as ability to play out some tough moments. The rules are a lot more balanced between bowlers and batsman. The typical game goes like this: Team A bats and Team B bowls. Team A scores 400 runs and lose all their wickets (each team gets 10 wickets, which is 11 batsman batting and 10 getting out). Team B comes back and tries to take down Team As score and build on it. So Team B scores 500 runs and get all out, they now have a lead of 100 runs. Team A comes back to bat with a deficit of 100, so initially they try to get over that and set a target for Team B to chase down. So they score 300 and Team B has 200 runs to chase down to win the game. Now Team B scores 201 and wins the game. The tricky part is the pitch used will detoriate over the days (Generally) and will be harder for the batsman to bat on as days go by. (They generally play around 6 hours a day). The team also has to consider if they will be able to chase down the target and win the game, in certain cases winning might be impossible situation and teams will opt to draw the game instead, which means they preserve their wickets and try to bat of whatever is remaining in the 5 days (this itself is a huge task at times). Next format is the 2nd format that came out, One day internationals (also called 50-over Limited Overs). So as the name suggests this is a one-day match, typically 8 hours long. Each team gets to bat 50 overs (or till their 10th wicket falls), (each over is 6 balls, unless theres foul balls bowled, so 300 balls per team per match). So the format is very simple for new cricket watchers to understand. Team A bats for 50 overs scoring 300 runs loosing 7 wickets. Team B comes to bat and they need to score 301 runs inside of 50 overs to win. Simple as that. If they loose 10 wickets or finish their 50 overs without scoring 301 they lose. This format was widely popular and still produces some of the most thrilling games, since it sort of brings elements of playing the long game as well as excitment of closer finishes and pressure moments. The latest, newest, flashiest format is the T20 format (Short for Twenty20). The rules are very similar to ODI format above. Each team though gets 20 overs to bat (so the format is shorter) games last less than 3 and half hours. So this format is generally a very good starting point for new people to get into the game, its a lot more batsman oriented, lots of action. Cricket haves 3 different formats catering for different tastes, and a lot of people are fans of T20 but not Tests. And there are people who love tests and hate T20. I love all three formats having watched the game from when i was a kid and generally find different challenges in each of the format very engaging. Hopefully i sort of gave a ELI5 answer to that, my first ELI5 answer and it had to be cricket related!"
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5vrbch | Impossible colors/forbidden colors | How this work i was trying to read wikipedia page but topic is to hard for me to understand in english and I could't find explanation in my native language. | Physics | explainlikeimfive | {
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"Some colors cannot be perceived by our eyes, but we can trick our brain into \"seeing\" them. An easy trick that work for most people is to rely on \"color fatigue\" (after watching the same color for a while, your brain will adapt to it and try to compensate by shifting your perception toward the complimentary). This can allow to see over-saturated colors when you then move your sight on something else, as the signals from your eyes gets further shifted by your temporary brain \"adjustment\" from color fatigue. Mixing separate inputs from each eye can also lead to seeing \"impossible\" color combinations. If your left eye is screaming \"red\" and your right one screams \"green\", your brain can understand \"reddish-green\".",
"It helps to distinguish colors -- what we feel -- from wavelengths, which (as far as we can tell from science) are the real things. Just like how \"smells and tastes\" are different from \"elements and chemicals\". They aren't one-to-one. Some colors we feel are actually the presence of one category of wavelength plus the *absence* of another. This means some colors cannot be added or blended the same as other colors. So it's a bit like: > \"With your left hand, feel a hard cold surface like this chunk of ice.\" > \"Brr! Okay.\" > \"With your right hand, feel a soft hot surface like this balloon of heated sand.\" > \"Squooshy. Got it.\" > \"OK, now it's really simple... I want you to imagine softhard coldhot thing.\" > \"Uhhhhh, like... a tennis-ball at room-temperature?\" > \"No! I mean all of it together.\"",
"We can only see so many colors, limited by our human eyes. Presumably, other animals like [the Mantis Shrimp]( URL_0 ) can see more colors. We'll never know until we learn how to comprehend them.",
"The color Magenta is actually \"made up\" by our brain. There isn't a wavelength that represents it (as it technically falls \"outside\" the visible color spectrum: it would both have to exist to the left of ultraviolet and to the right of infrared at the same time), so our brain just interprets \"absence of green signal\" as Magenta. Here is a more detailed explanation: URL_0"
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5vrbm6 | If coal turns to diamonds through pressure, could we dump a bunch of coal on the ocean floor to turn them into diamonds faster? | a quick roadmap for those just joining us: [actual answer 1]( URL_4 ) [actual answer 2]( URL_2 ) [one of the only off topic threads i approve of]( URL_5 ) [the plot thickens!]( URL_0 ) [a good way to honor your fallen loved one]( URL_1 ) [shameless plug to the mods]( URL_3 ) | Other | explainlikeimfive | {
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"Nope, it's nowhere near enough pressure. The pressure at the bottom of the mariana trench is nearly 16,000 psi. The pressure required to make diamonds the natural way? 750,000 psi. You'd have wet coal. *EDIT: The longer this post has been up the progressively weirder the replies have gotten. They moved from scientific inquiry to shitposting to dadaist art pieces, what is happening*",
"Despite being quite heavy, the ocean is WAY too little pressure to turn coal into diamonds. For diamonds, we're talking 237,000 to 1,300,000 atm. The bottom of the Mariana Trench, one of the deepest parts of the ocean, has about 1,070 atm. So we don't even need to get into the trouble of retrieving stuff from the deepest part of the ocean, because it's just gonna be wet coal. As something of an aside, most diamonds are not actually formed from coal. Much of the carbon that went on to form diamonds likely predates any of the living material that would form coal altogether.",
"So. In keeping with the spirit of the thread and not engaging in trollery, the followup question is: If on the bottom of the ocean, the carbon is just \"wet coal\", HOW DEEP of a (completely theoretical) ocean would be needed to provide the necessary pressure to form diamonds?",
"thanks for the answers! now i know what to do if i want wet coal next time james cameron invites me on an expedition Edit: a lot of people seem to think I'm commenting on the rarity of diamonds, and that I am hatching a grand scheme of deep diving to my diamond trench to live alone with my riches while you are left to fight amongst yourselves for your slowly disappearing supply of diamonds. I assure you I just had a random shower thought, and this is not a commentary on \"Big Diamond\"",
"Actually diamonds being formed from coal is a myth. Coal seams are sedimentary rocks that form in horizontal slabs. Diamonds are formed in vertical shafts full of igneous rocks. Source: URL_0",
"Diamonds, as found in diamond mines, are not now nor were they ever \"made of coal\". Coal is a complex hydrocarbon. It does have a lot of carbon in it, but it's got too much other stuff to ever simply be crushed into diamonds. Diamonds are what you get from nearly pure carbon subjected to almost irrational pressures and heat, and they _slowly_ crystallize. So pure graphite looks like a bunch of little hexagonal dinner plates. It's all flat. A large flat sheet is this \"graphine\" you hear of. Then you just keep squeezing a whole stack of that from all sides and the little connections that make the array of dinner plates shape become an array of cubes with cross members to make diamonds. That's a lot of pressure. A lot of heat. And a lot of time. Imagine trying to turn a stack of dinner plates into a brick just by finding something heavy to put on top of them. That's just not going to work. The plates just break. So then you need to push them from all sides. Then you need to melt them to basically lava. Then you need to keep the pressure on until the lava becomes rock. That's a lot of heat and pushing. The bottom of the sea is not as hot as lava. It's not enough pressure. And if it was, the water would go between the plates and you'd never get your brick. So coal is what happens if you burry a bunch of dead plants and get it sort-of hot under a bunch of pressure. Diamonds are what you get when you crush pure carbon with a signficant percentage of the earth's heat and weight without letting it get mixed around.",
"No. The pressure at the bottom of the ocean is 15,750 psi. The pressure required to make diamonds is around 510,000 psi. That's more than 10 times whats is needed. But could if we could created that kind of pressure, would that turn the coal into diamonds? No, we still need to heat them up. Could we heat them up and put them under that kind of pressure? Yes! Infact we regularly do this. [Synthetic diamonds are are regularly produced thing.]( URL_0 )",
"Not really no The sort of pressure required to form diamonds is well beyond anything found in the ocean And the amount of time it takes diamonds to form is in the millions of millions of years, so even if you could halve this amount of time it would still be completely pointless There are however other methods available to make synthetic diamonds URL_0",
"Diamonds largely form due to kimberlite pipes, am occurrence in which the material that will form the diamond shoots up from lower in the Earth's crust, causing the material to quickly cool. This quick cooling is what causes the formation of the diamond, not just pressure. Another comment pointing out vertical igneous formations is likely referring to this process. At least this is one way diamonds form, perhaps there are others.",
"Even if we could, we don't need to. Diamonds are not all that rare. The industry holds back supply intentionally to keep prices up.",
"It could be done on Jupiter, however. Jupiter is in fact, not massive enough to fuse hydrogen (as the sun) but if you dropped deuterium into Jupiter, it would begin fusing near the center and releasing fusion energy.",
"I heard an expert on diamonds on NRP the other day---and I'm an expert on pretty much nuthin' so take this for what it's worth---and he said all diamonds carbon date from something like 3.8 billion years in age to 4.1 billion. (I can't remember the exact figures.) Anyhoo, if you take into account the age of the earth, and that there aren't any diamonds say 5 billion years old or just a billion years old, wouldn't that indicate that there was probably something else geologically going on than simply pressure and time?",
"Diamonds do not ever come from coal! Ever ever ever! Ever never! lol This is one of the first things I teach my students. Diamonds come from igneous intrusions called kimberlites. These arise from the deep mantle and are very old. Coal is a sedimentary rock formed from lithified plant matter. Plants (usually deposited in swamp conditions) are layered on top of one another and slowly buried. There it is subjected to pressure and a bit of heat to form peat then lignite then bituminous coal. When bituminous coal is subjected to further heat and pressure it is then metamorphosed into anthracite coal. This is the nice shiny coal that burns relatively cleanly. It's found in the Appalachian region here in the US (among other places). If it's subjected to any other heat and pressure from tectonic forces then it'll most likely be destroyed and result in partial or complete melting and form a new non-diamondy rock.",
"Diamond is a very ordered form of carbon and it is created under both heat and pressure. The pressure on the ocean floor is a vacuum compared to the pressure in the mantle and earths crust. The weight of a few hundred miles of atmosphere and water pales compared to the weight of miles of rock, and the heat of mantle plumes. The pressure on the ocean floor is not enough to force carbon into the configuration necessary for diamond nor does it have the heat needed to make the carbon pliable enough to change form.",
"Nope. Coal is not the source of diamonds. Diamonds are actually formed from graphite melting and recrystallizing under intense heat and pressure.",
"As the top answer says nope. But you can grow a diamond...using graphite, heat, pressure and special equipment. URL_0 I am a GIA trained diamond grader, AMA :D"
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5vrc53 | Why does some scientists/countries still want to go on the moon ? | Physics | explainlikeimfive | {
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"The moon is the closest large object to earth in space, so going to the moon allows us to develop and test a lot of technology related to landing on and moving around on solid, non-earth objects. Mars would be better to colonize for several reasons (atmosphere, temperature, soil, similar hours in a day, etc.), but we don't have the technology to set up a space colony yet and the moon is a much closer place to do testing.",
"The single largest reason is that it has a lower \"Delta V\" than Earth. That's just a way of saying that since the escape velocity on Earth is about four times higher than the Moon, it costs a lot more fuel to lift the same load out of Earth's gravity well than the Moon's.* If we're serious about doing things in space, and not just LEO, we're going to need to address the high Dv required to leave Earth. Fuel is *expensive* in every sense, because the essential problem of rocketry is that you have to lift your own fuel. Therefore fuel savings become a massive proposition, defining what kind of loads you can affordably send into LEO or further. The reason why people look at the moon, is that it's a compromise between a pure space station, and a colony. You can reap the benefits of having a *little* gravity, while still having close access to freefall and vacuum. As with Mars, shielding from radiation would be accomplished by tunneling, and there might be something useful for fuel conversion there as well. It doesn't present all of the advantages of a space station or a bubble-formed asteroid colony, but it has the advantage of being something we actually could conceivably make soon. The problems are numerous though, and while the Moon has a much lower gravity than Earth, it's still a problem. *Actually Dv is just \"Change in velocity\" and is shorthand for all of the acceleration you'll need for the whole mission, most of which is going to be a result of escaping from Earth's gravity well. Obvious Dv is a function of the gravity well you're in, and obvious how much you need to accelerate defines your fuel budget."
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5vrdna | What is the difference between a bad headache and a migraine? | Biology | explainlikeimfive | {
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"I've had migranes since i started puberty. I'm an adult now and they have changed over time. I no longer get pain with my migranes in about 95% of cases. What i do get are some of the other effects of a migrane. [holes in my vision]( URL_1 ) disruption to [proprioception]( URL_0 ) which is the sense that keeps track of where our body is in space. I can get numbness and tingles in my limbs I get light and sound sensitivity. And a sort of nausea that is in your head rather than your stomach. Migranes are about disruption to your nervous system. All of the symptoms i describe are signals from my senses not being received or processed correctly by my brain. Migrane pain is the same sort of misfiring.",
"As a 17-year migraine sufferer, this sums it up pretty well: URL_0 The only thing I would add is that I've honestly never thought about taking my own life, but I've had a migraine so bad that I didn't want to live. I just wanted to stop breathing an cease to exist.",
"The other poster here is totally right. The noticeable practical difference between a normal headache and a migraine is intensity. It's akin to comparing a sore wrist to a broken wrist. The pain is absolutely flooring. My brother and I have unanimously decided that it feels like your skull is being pried apart at the tiny bone boundaries. They're real nasty"
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5vrh4h | Why in most computer calculations 1/(0.2-0.1-0.1) gives the correct result but 1/(0.3-0.1-0.1-0.1) doesn't? | In all programming languages that I've tested, in MS Excel, in Google Sheets, in Windows and MacOS caluculators, in Wolfram and so on, the calculation `1/(0.2-0.1-0.1)` give an error or "infinity", but the calculation `1/(0.3-0.1-0.1-0.1)` gives a number ~`-3.6E16` and `1/(0.4-0.1-0.1-0.1-0.1)` gives the same number only positive? Mathematically, they should all give the same result. Something in floating point calculation is "wrong". | Technology | explainlikeimfive | {
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"The problem is that it's doing the calculations in binary and can only store a limited number of digits. 0.1 can't be stored exactly in binary, in the same way as 1/3 can't stored exactly in decimal. You get rounding errors similar to the problem you'd have dealing with 1/3 in decimal: 1 - 0.333333 - 0.333333 - 0.333333 = 0.000001",
"When represented in binary, 1/10th does not have an exact representation, much like 1/3 in decimal. If you represented 1/3 as 0.333, 1 - (0.333 + 0.333 + 0.333) = 0.001, not 0. You are basically doing that, but in binary. > Mathematically, they should all give the same result. Something in floating point calculation is \"wrong\". Actually, no. Floating point was designed to represent approximate values, not exact ones. If you measure you drive to work, you might come up with 10.22 miles. But that doesn't mean *exactly* 10.22, it means 10.22 with a reasonable margin of error. That's the kind of value that float point is used for, and managing that error is your responsibility. In your case, 0.2 doesn't mean *exactly* 0.2, it means a measured value we are rounding to 0.2. If you need exact representation, you need to use a different data type than floating point, like integers or rationals.",
"rounding errors. Basically, when you store a decimal number in a computer, it is stored as a floating point number. That means that the computer stores a certain number of significant digits, and an exponent. If the number has more than a certain number of significant digits, then it truncates the number and they are lost. eg: if a computer stores 8 significant digits, then 1.2345678 is stored as 12345678 10e-7, but 1.23456789 would lose the 9 and *also* be stored as 12345678 10e-7 because it only stores 8 significant digits. The result you are getting is a very large number, but that is what one should expect from dividing something by a very small number Basically, however the math interpreter in the program parses that math problem you posed works, it is getting a number with more significant digits than its floating point variable stores, and truncating the number, which leads to a VERY small, non zero number- normally, this wouldn't be an issue at all because that error should be drowned out by the rest of the result, (who cares if the result is 1.2345678 or 1.23456789, either way it's close enough for most engineering purposes), but since you're trying to achieve a 1/0 calculation, you need to exactly return to 0 and that minor error is screwing up the results noticeably. That said, I pulled up windows calculator to see if I could reproduce the error there, and I could not, so I think it's more a bug with those programs. However, I could not reproduce the error in Wolfram alpha, all of the above produced infinity as their result"
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5vrjk2 | How do TV shows and films make actors/actresses appear decades younger so easily? | I was recently re-watching HBO's Westworld and there is a flashback scene where the character played by Sir Anthony Hopkins is pictured at least thirty years younger (I think this was episode 4 but I could be wrong). Is this make-up alone or is there computer software involved as well? | Other | explainlikeimfive | {
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"It was CGI and is, by no means, easy. There's a reason you didn't see much of young Ford. There's also a certain sci-if movie out that did this with an actor who was actually deceased. They hired someone who looked a bit similar and could do his voice, and then painted over his face to match the actor's face. But probably the most famous example of this would be TRON: Legacy, which had a deaged Jeff Bridges for half the film."
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5vrm6b | why are toilet doors push to enter, then pull to exit after you've just washed your hands. | Other | explainlikeimfive | {
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"Opening a door into a hallway when you can't see anyone coming is not very safe. Besides you just washed your hands so you shouldn't be leaving germs in the handle. Now think of all the other handles you touch that day. Lol",
"Fire code. If something falls in front of a push to open door, you cannot open the door. If something falls in front of a pull to open door, you can open the door. Because bathrooms tend to only have one door, in the event of a fire, something stopping the door from opening would be on the inside, where the occupant has an opportunity to move it, freeing the door, and allowing escape.",
"Generally bathroom doors are on high traffic walkways. You don't want doors opening outwards into someone.",
"If someone really has to go they need to be able to just barge in and keep their momentum going forward"
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5vrp2k | Why do bugs and other tiny insects not break a limb or die from falling a great height. | Physics | explainlikeimfive | {
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"You'd think that an ant falling from three feet is like a human falling off a skyscraper. But this isn't the case because of the square-cube law. As it relates to tiny things, the smaller something is, the more resilient it is to stresses. What the law means is that as an object's surface area increases by a power of 2, its volume (and mass) increase by a power of 3. So something that gets a little bit bigger will weigh a lot more. When a bug falls, it weighs so little with respect to its surface area that it has a really low terminal velocity, aka it will fall very slowly. Because of this in addition to how strong their little bodies are for their mass, they will land like nothing happened.",
"I actually asked my lab professor about this the other day. We were doing fin clips on these little fish and one flopped onto the floor but it was fine, and I asked him if they get brain damage from falling off the counter. He said that one of the interesting things about how organisms scale with size is that they're basically made of the same stuff as you or I (well, more so fish than insects) but because a 3-centimeter-long fish weighs much less than a human, the force it experiences when it hits the ground is much smaller. So it's much less damaging to a tiny organism, even though the equivalent for us would be falling off of a ten-story building. Insects have really strong exoskeletons as well, for their body size.",
"Small objects have a lower top speed when they're falling, and they don't weigh enough to get hurt."
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5vryas | iPhones regularly start to malfunction after 2-3 years of use. Why is this not considered a bad product at $700-800 MSRP? | Technology | explainlikeimfive | {
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"What sorts of malfunctions are people experiencing? I'm not trying to be snarky; I honestly didn't realize there were problems with the products. We (my family) bought 3 iphone 5s in December ~~2102~~ 2012 (thanks, /u/naf623, for pointing out my error!) and haven't have one bit of trouble with any of them. 4 years of constant daily use by all three and they're still all going strong. Have we just been lucky? Heh I hope I don't jinx us with this post!",
"Do you have any stats/articles/info to back up your claim that iPhones 'regularly' malfunction after 2-3 years? From what I can see, Apple does a great job supporting devices through software updates for years after release. You can have phones that are 3-5 years old that are not only functioning properly but updated to include new features and, perhaps more importantly, security protocols. It's my opinion they have a better build quality than most competitors as well. They also have an integrated support system so if your phone does start to malfunction you don't necessarily have to deal with a call centre or your carrier's sales staff, but can bring it into an Apple Store. If I'm spending 700-800$ (or more, a lot more) on my phone, do I want: **Google Pixel**, which I can't buy/return in person, comes with software/call centre support, and might only be eligible for Android updates for 18-24 months, or: **iPhone**, which I can buy/return in person, get support in person, and I know will be continuously updated for years to come?"
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5vs1wp | What's so special about the AMD Ryzen | Specifically why did it take so long to catch up to intel and how did they do it? | Technology | explainlikeimfive | {
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"Someone will probably come along and give you a longer more detailed explanation but the TLDR version is: Bulldozer cores were designed for high frequencies and multithreading at the sacrifice of ipc(instructions per cycle). Bulldozer's IPC was actually considerably lower than AMD's previous architecture. It's a common misconception that AMD couldn't afford to build a good cpu. That wasn't the case, they just designed the wrong cpu for the market. So, while AMD did improve upon Bulldozer as best they could, they, almost, immediately began working on Zen. So the thing with Intel is that they really haven't designed a new architecture since Ivy bridge (or maybe it was core 2), they've just been making minor improvements and node shrinks each year. That couldn't be done with bulldozer, it had to be redesigned from the ground up, and building a new cpu architecture takes years. Now, what's so different about Zen? Well, Bulldozer cores aren't really cores. You could more accurately describe them as \"ALU Clusters\" (as a friend of mine puts it). Zen cpu cores are actual cores. [this]( URL_0 ) will help visualize it. On the left, is a bulldozer module (2 bulldozer cores). On the right is a single Zen core."
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5vs21e | Why is it so challenging for developed nations to completely eliminate poverty? | Economics | explainlikeimfive | {
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"Poverty is a moving target. As a country's standard of living increases, the standard for what is considered poverty also increases. Poverty is often defined relative to national averages, which means mathematically it can never be eliminated.",
"Have you heard the expression \"give a man a fish, and you'll feed him for a day, but teach him how to fish and you'll feed him for a lifetime\"? Most anti-poverty programs are just giving people fish - in the form of money, donations, services, etc - but leave them incapable of fishing for themselves, so the next day there's even more people who need fish but still don't know how to get it. The ideal anti-poverty program would transform hungry people into fisherman - in put another way, economically productive citizens who could earn, save, invest, etc - so that they could take care of themselves and help others. But transferring skills and instilling a work ethic, values, etc is incredibly challenging in the best of circumstances. We all know kids from wealthy families who were given plenty of opportunities but never got their act together. Now add in all the chaos associated with poverty - crime, alcohol & drugs, poor transportation, poor health care, lack of education, unplanned pregnancy, etc and you start to wonder if its even possible to move large numbers of people off of welfare. Many people, and perhaps even the majority of people in developed countries, believe that it isn't, which makes them skeptical of any government program that attempts it. Personally, I'm more of an optimist, but I do think you get the best results by setting up things like first-time home buyer programs or child care tax credits that are designed to help people that are on the right path but still need a little extra help. People still have to learn how to fish for themselves, but you're making it a little easier for them to get started."
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5vs3qn | Why do humans primary only have 3 eye colors? | Biology | explainlikeimfive | {
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"they are the most dominant traits. there are some people with slightly different eye colors. (yellow and even purple have been found on occasion.) but primarily we have brown blue and green as the most common as they are the traits which \"overwrite\" other eye color genes. your eye color is determined by your parents genes. some combinations of eye color are more dominant than others. so brown eyecolor superceeds blue eye color. thus parents with one having blue and one having brown are more likely to have a brown eyed child. over many years eventually other colors get phased out due to being recessive (not dominant) so some colors like purple may have been common in an area long ago and got taken over by brown as new people showed up.",
"There aren't only three main eye colors; there's a whole spectrum. Your eyes can be pure pale blue, pure dark brown (so dark they look black), or anywhere in between. There are many names for the various steps along this \"in between\" spectrum: green, chestnut, hazel, etc. We think of eye color in terms of a few main colors, because our culture points out and categorizes people by these colors specifically. Nobody says \"my eyes are 30% towards the lighter side of the spectrum\"; they say \"I have green eyes\". It's the same thing we do with skin color. We call people \"white\", \"brown\", or \"black\" despite there being a continuous range of skin color from very pale to very dark. They're just easy categories."
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5vs3tl | Why does the U.S government own most of it debt? | Why does the government loan itself money. If program __x__ has a surplus and buys bonds to fund program __y__, why wouldn't they just balance the budget so both programs get what they need? | Economics | explainlikeimfive | {
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"This isn't a complete answer, but it might help. A big organizations isn't like a house hold. At home, you're in charge of your budget, and it's up to you to give money from eating budget to the home improvement budget if you need to buy a new lamp for example. You hold all the power, so you can take and give as you want (assuming you're not married that is). On the other hand, power in any big organization is distributed between different people. In the government, this separation is setup by law. They don't want any one part to become too strong. So, now you have a bunch of people with some power. And, money is simply another form of power. So, the guy running the FBI has power (and money), as does the guy running the EPA. **As far as I know, this isn't a real situation** Let's say the EPA needs money, and the FBI has money. Now, if the FBI just gives the EPA $100,000,000, they lose the Power that money brings. On the other hand, if they were to buy bonds from the EPA, they would just be loaning that power, with the promises of getting it back + more in interest. Now, that answers the reasons why someone doesn't transfer the money. But, since the FBI and EPA don't actually fund themselves this way, it doesn't say why the government owns bonds. As far as I know, it's mostly the Feds and the Social security administration who hold Treasury bonds. But, local government savings funds / wealth funds also hold bonds. And, they all do so for different reasons, each would take it's own ELI5."
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5vs78d | The first SHA1 collision by Google | Technology | explainlikeimfive | {
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"SHA1 is a hash algorithm. It takes some data, runs it through complicated math, and gets something like a fingerprint. You always get the same fingerprint for the same data, but you can't get the data from the fingerprint. SHA1 only produces a fingerprint of 160 bits (1's and 0's). That's like 40 hexadecimal numbers long. There are only so many combinations of 160 bits. That means sometimes different data will have the same fingerprint. Ideally, it's should be nearly impossible to get a specific fingerprint *on purpose*. If you see a fingerprint, you shouldn't be able to figure out what data you need to result in that fingerprint. The only way would be to keep trying random data over and over until it matches. The guys at Google have done math wizardry to come up with a shortcut. Now it takes less time to find a matching fingerprint. Why does this matter? Let's say your password is \"Dog123\" and the hash is \"ABCDF\". Computers usually store the hash of a password and just compare it to the hash of what you typed in. Instead of trying all possible passwords until they get \"Dog123\", they can cheat and find out \"ILikeDogs321\" has the same hash. It's not your password, but since your computer only compares the hash it still works. You might also use a hash to verify the software you downloaded is the software you wanted. This method potentially allows someone like the NSA to insert a virus into software, but make it appear as if it's not been tampered with since the hashes match."
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|
5vsaox | How the prices of foreign commodities/goods regulated in the USA? | I was recently at an Indian store in the US and was looking at the prices of some of the products and noticed that some of the prices were at least 5 or 6 times the MSRP prices in India. They even have the label for how much it costs in India. *For example, a set of three(+1 free) bar of [soaps]( URL_0 ) costs Rs. 117(approx $1.72). Yet at the Indian store they are selling the same soaps out of the boxes as separate units(some of them even have a label "Not to be sold separately") for $1.75 each. * On the other hand if you look at Amazon's prices. You can see that they are only slightly more than the MSRP found in India which is very reasonable. I could not find the same set of soaps(as above) in Amazon USA so I compared a different set of soaps. [Price in India]( URL_2 ) times 4 because there are only three bars in this package. [Price in USA]( URL_1 ) * This is just one of the examples. The prices of almost all the goods in Indian stores are jacked up to at least 5 or 6 times the MSRP in India. * So my question really is: Is there a governing body that specifies the prices of each of these products? Are there any regulations as to how these products need to be priced? The products basically contain a little label with the stores name and the price of each product. * Do stores of other countries in US see similar patterns too? | Other | explainlikeimfive | {
"a_id": [
"de4fqqp",
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"text": [
"> Is there a governing body that specifies the prices of each of these products? No > Are there any regulations as to how these products need to be priced? There's sales tax in some places. Couple things going on: 1. This is presumably shipped all the way from India to the US, that isn't free. 2. Wages are higher in the US, meaning for every person involved in selling you the product in the US, you're paying quite a lot more for their time than you would in India. 3. Stores charge what people are willing to pay, people in the US are much wealthier than those in India so stores will up the prices as high as they can before people stop buying.",
"For the overwhelming majority of products, no, prices are not regulated except by the market and the competition. Everything is worth what it's purchaser will pay for."
],
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6,
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| [
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5vsgyl | Will there be a point of video games graphics becoming so advanced that the technology will plateau and the human eye won't be able to perceive any further improvements? | Technology | explainlikeimfive | {
"a_id": [
"de4k46o"
],
"text": [
"Perhaps, but we are still far off from that point. Our brains are wired to notice all kinds of details about lighting, things that tend to be computationally intensive to simulate. Hair is still very hard to render believably in real time, for another good example."
],
"score": [
5
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"text_urls": [
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| [
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|
|
5vshi6 | How is the economy, treasury, and general flow of money affected by a massive lottery win? Where does it usually comes from are there any adjustments made or changes made to the fiscal system? | Economics | explainlikeimfive | {
"a_id": [
"de4gv0q"
],
"text": [
"[US] Lottery winnings are generally funded from the sales of tickets themselves. No new money is being created."
],
"score": [
3
],
"text_urls": [
[]
]
} | [
"url"
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| [
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|
|
5vsmdb | Why do we produce earwax and what benefit does/did it have? | Biology | explainlikeimfive | {
"a_id": [
"de4ijd2"
],
"text": [
"Earwax is a lubricant, just like beeswax or tallow, and it helps to keep nasty things out of the ears."
],
"score": [
3
],
"text_urls": [
[]
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| [
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|
|
5vsnqq | Why aren't computers and other electronic devices instant, why is there a 'loading' time? | Technology | explainlikeimfive | {
"a_id": [
"de4izxq",
"de4q5yv"
],
"text": [
"because of how electronics work at the basic level. everything is synced to a metronome called the processor clock. the entire orchestra of several billion transitors operates on the processor clock's conductor timing. when processor clock says your data's ready to read, then read, not before. at the electrical level, it's because electricity doesn't flow instantly. it takes time to charge a circuit until the voltage reads more than 1.5volts, reading as a 1. and time to discharge a circuits so the voltage is less than 0.5volts reading a 0.",
"All those electrons still need time to move and that stacks up. An instant is still a measure of time. Now stack that up. Instants become seconds- minutes - hours."
],
"score": [
7,
3
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| [
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5vsotl | How can anything POSSIBLY be random? Doesn't everything happen as a reaction of something else? | Physics | explainlikeimfive | {
"a_id": [
"de4k13g"
],
"text": [
"It depends on how you define random. If you define it based on someone's relative knowledge, then you can easily have things that are random because people don't know enough to predict them. For example, you may be able to know how a coin will land if you have all the information about how I'm flipping it. However, an average person has no way of knowing that so it is random to them. Random can also be defined as without method or conscious decision, which is pretty similar to the above. Based on that, I think your question really boils down to \"are the limits to our predictive models and/or our knowledge about the physical world?\" And that I can't answer because I don't think science has gotten that far yet. Quantum mechanics poses some issues with having complete knowledge of a system, but that's about as much as I know on that topic."
],
"score": [
3
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"text_urls": [
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| [
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|
|
5vst7l | What's the point of the "press any button to continue" screen in some video games, why not just boot to the main menu? | Technology | explainlikeimfive | {
"a_id": [
"de4k6fg",
"de4nces",
"de4o8zp"
],
"text": [
"Artistically maybe they wanted to show a \"clean\" screen without a bunch of menu options on it. But there's really no technical reason to have one. A bunch of games boot directly to the main menu. A better question is why are there unskippable splash screens? And the answer to that is that the game is loading in the background, sometimes the menu itself is loading in the background (ex: Just Cause 3, though for a cool reason, because there is no transition from menu to game when you're ready to play, the menu is created from your save file progress... look up a video of it, you'll understand)",
"[This is the thread]( URL_0 ) from when this was asked last month. I particularly like the answers from /u/PrionBacon and /u/white_nerdy",
"Some games use(d) it for deciding player order. The controller that first gave input would be player 1, for example, and could then navigate the menues w/o being bothered by anoying siblings."
],
"score": [
13,
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"https://www.reddit.com/r/explainlikeimfive/comments/5qaxex/eli5_why_does_some_games_and_programs_have_these/"
],
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| [
"url"
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|
|
5vswo7 | How come you get tired of eating the same dinner more than two days in a row but you can eat the same breakfast for years on end? | Other | explainlikeimfive | {
"a_id": [
"de4nfsh"
],
"text": [
"Back when the U.S. military was developing MREs, they were trying to figure out how to get troops to eat the same handful of meals over several weeks. They realized everyone loved heavily spiced food at first, but got burnt out on it quickly. Meanwhile, they had no problem eating bland foods day after day. Since breakfast foods tend to be bland, it's easier to eat the same thing over and over again than if you had the meals you normally eat for dinner, which are usually flavorful, every night."
],
"score": [
5
],
"text_urls": [
[]
]
} | [
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| [
"url"
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|
|
5vsy1p | Why do we perceive the Earth's rotation so slow? | If the Earth spins at 1,040 mph, how come we don't really feel like it's doing it so fast. | Physics | explainlikeimfive | {
"a_id": [
"de4l72d",
"de4m9rm"
],
"text": [
"You're moving along with it. So to you, it is stationary. It's not accelerating or decelerating (much) so there's very little change for you to feel, and the atmosphere is (mostly) rotating with it, so there's no 1000 mph headwind. The same way you don't 'feel fast' in a car moving at a high, but constant, velocity.",
"You don't ever feel velocity. You feel acceleration. When a car is stopped at a red light and the light turns green, you feel the car accelerate to a higher speed. But if you stay at a constant speed you don't feel any force, because there is no force. The famous equation is F=ma . F being force, m being mass, and a be acceleration. With no acceleration there is no force. Since the Earth is spinning at a very constant rate there is no acceleration so there is no force for you to feel."
],
"score": [
3,
3
],
"text_urls": [
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} | [
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| [
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|
5vt363 | Whats going on in our brains when we zone out and our vision splits into two? | Biology | explainlikeimfive | {
"a_id": [
"de4mhax"
],
"text": [
"it's more about your eye muscles disengaging and driftng out. Technically, I guess the brain in ignoring the double vision, which usually is a catalyst to respond by keeping the eyes focused"
],
"score": [
3
],
"text_urls": [
[]
]
} | [
"url"
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| [
"url"
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|
|
5vt6ni | Why would a 45g bar of chocolate cost 80p (cents) but a 300g cost £1 (dollar)? | Economics | explainlikeimfive | {
"a_id": [
"de4nhab"
],
"text": [
"Because more of their costs reside in the packaging and distribution than in the chocolate itself. Think about buying sand in giant 200 pound bags or individually wrapped grains, how do you think the price would change per pound?"
],
"score": [
8
],
"text_urls": [
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} | [
"url"
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| [
"url"
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|
|
5vtewc | What is the purpose of a credit score? | Watching all of the advertisements about "checking your credit score" has got me wondering: If someone is making a decent amount of money and is on good terms with a bank, why is a credit score necessary in any way? | Other | explainlikeimfive | {
"a_id": [
"de4pk40"
],
"text": [
"A score is just a numeric quantification of your credit worthiness, often provided as part of a paid service to consumers. Most lenders do not care about a score per se, they look at everything to determine exactly what terms of a loan they will offer. Being \"on good terms with banks\" isn't a precise statement. Banks also want to know how much credit you already have, how much credit have you been recently seeking or using, how often and how long have you held balances or missed payments, and so on."
],
"score": [
3
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"text_urls": [
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| [
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|
5vti8i | Why is Wednesday pronounced "wenzday" instead of "wed-nesday"? | Other | explainlikeimfive | {
"a_id": [
"de4qog3"
],
"text": [
"Originally it was Woden's day lots of the days are named after Norse gods Thor's day Freya's day or Moon day and Sun day."
],
"score": [
3
],
"text_urls": [
[]
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} | [
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| [
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|
|
5vtmdz | Information Tech professionals of Reddit... How can you tell what people are using their work computers for? | Someone in my office got fired today for unethical use of their work computer. How does IT know what is going on? Does clearing search history/browsing info/ cookies/ ect really do anything? What information can IT departments tell about computers and how? | Technology | explainlikeimfive | {
"a_id": [
"de4rf06",
"de4sfyu"
],
"text": [
"All your internet traffic is sent through a device called a router. That router keeps logs of what IP address (a unique identifier for each computer on the network) performs what actions and what traffic goes through it. If a known viral program is accessing the internet through your computer, we get alerts. If you're visiting websites that you shouldn't be, we get alerts. The history on your browser has nothing to do with it.",
"In my last job we had software which would scan the machine for any images which may have been porn. We also got a monthly report on the web monitoring software which would highlight questionable websites visited, time spent on youtube etc. ELI5 - IT departments can monitor everything you do on your computer, it just depends on the company policy how indepth the IT admins check it."
],
"score": [
10,
4
],
"text_urls": [
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| [
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|
5vtr1o | Why is Arnold Schwarzenegger celebrated as the greatest bodybuilder of all time, if all of them were using steroids at the time? | Other | explainlikeimfive | {
"a_id": [
"de4sr9k"
],
"text": [
"I think steroids they were using back then were legal in competition. I've seen interviews where he talks about using them quite openly. Also, back then was a bit of a 'Golden Generation' for bodybuilders. Arnold was a celebrity and he lifted (see what I did there) bodybuilding into the mainstream. Nowadays every man and his dog is a bodybuilder if they have an IG account."
],
"score": [
3
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| [
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|
5vty34 | In video games, why is it so difficult for developers to make it so objects do not pass through one another? | For example, in Ghost Recon: Wildlands my character's weapon passes through his tactical vest when in reality it should be in front. | Other | explainlikeimfive | {
"a_id": [
"de4y9z2",
"de4uzqd",
"de4u4wv"
],
"text": [
"100% accurate collision detection is extremely processing power intensive work for a computer so much so that it's not an option for real time video games. There would just be to many checks that would need to be made to see if things are colliding instead game so devs use extremely simplified collisions shapes ( like rectangles to approximate a human body) that are rarely accurate to the object in question. Many objects in the game world just simply won't have collision detection enabled period to reserve processing power. In the case your talking about it's likely that the clothing has no collision detection and the animations are likely mostly canned instead of procedural. Both would need to be true in order for the game to notice the clipping and to modify the character model to prevent it. It wouldn't be a problem if the game only had a static set of gear but since that game has a massive amount of customization it really stands out since they parent gonna enable collision or alter the animations for every single little piece of clothing as that would be a massive amount of work in itself. So answer to your question is the they cant because we don't have enough processing power to do it for a real time game. The same is true of many things when it comes to gaming so a lot of game development is fakery and optimization to create a just convincing enough world not necessarily a truly realistic one.",
"Imagine that you're in charge of creating the world around you. You have a pen that can draw anything in that space, and you have a rule book that creates all of the rules for that world. Let's say that you really want to see a sword fight in your world, so you draw two swords. After you're done drawing, you realize that they're just floating there, so you create a rule to have them swing at each other. So these swords start swinging, but you see that they just pass through each other. They don't stop and bounce off each other because your rulebook only says to swing, it says nothing about bouncing off of each other when they touch. So you have to create a rule that says that if the two swords touch, they have to stop their movement and bounce off each other. First you have to create a rule that determines what touching means. Then you create a rule about how to tell if the two things are touching. Then you create a rule about what to do when those two things touch. Not content with your clashing swords, you decide that you need create a much more elaborate fight. So you draw a couple of knights, some horses, a shield or two, and a fancy background. As you build more and more, you realize you have to create a lot more rules. Everything has to be defined. Suddenly there are a lot of rules and a lot of objects you have to keep track of. That's a lot of thinking you have to do! So you have an idea. You realize that you don't really care if the cloud you drew up in the sky bumps into a tree and bounces the right way, right? It's a waste of time to keep checking to make sure the cloud follows the rules about bouncing the right way, so you decide to take away the rule about clouds bouncing off objects. Now you don't have to worry about tracking the clouds, and you can focus on drawing other things and making sure everything else is following the rules you wrote. That's an oversimplification, but that's pretty much why hit detection isn't always done for all objects in games; devoting resources to hit detection takes computational resources and may not be worth it. A computer doesn't just \"know\" when two objects collide. If you've got a sword with very complex geometry, and another sword with complex geometry, it takes a lot of math to determine if any part of either sword is touching any other part of the other sword. In many instances, those kind of calculations have to be done for every object in every frame. In your example (the gun through the vest), it would take a lot of math to not only determine where your gun and vest were colliding, but also to calculate where the objects should be relative to each other. There is probably a hit box (the geometric shape that is tracked for hit detection) around the player and the gun, but it probably doesn't include all of the details of the vest, because that intricate geometry would be hard to track.",
"Particular objects in a character animation, such as the gun in a character's hands, hardly if ever have collision applied to them. The devs likely got that animation with motion capture. If the actor was not wearing a similarly-bulky vest when doing the movements, it won't translate perfectly in the character. All the game recognizes is the animation skeleton of invisible \"bones\" that move; everything else follows that. So yeah. It's possible to do better, but not really worth it to eliminate all clipping. You spend most of the time looking at the back of your character anyway."
],
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7,
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5vu33x | Why the Concorde was a problem to fly over land but military jets aren't? Why couldn't higher altitudes solve this problem? | `Preface:` So while I tried to look into sonic booms and how perhaps they could be better subdued, I found not much of an answer for this. Perhaps I need to do more reading. ******************************************** `Premise:` A concorde-type aircraft can reach supersonic speeds (peaking at mach 2), at an altitude of 60,000 feet. A military jet (F22 for example) can reach Mach 1.8 without afterburners, and above Mach 2 with afterburners. Military jets (I assume) fly over land and sea. Concorde was limited only to sea. The claim was that supersonic travel over land could shatter windows and cause noise issues. ******************************************** `Question 1:` Why was Concorde limited to overseas flights while Military jets are not? `Question 2:` Why would Concorde at 60,000 feet cause sonic boom noise and window shattering issues, and why wouldn't higher altitude solve this? | Physics | explainlikeimfive | {
"a_id": [
"de4vdfb",
"de4vxrj",
"de54xot"
],
"text": [
"Military jets generally aren't allowed to fly at supersonic speeds over the United States, outside specially designated \"High Altitude Supersonic Corridors.\" These jets are perfectly capable of flying slower than the speed of sound. (How else would they take off and land?)",
"The Concorde, as far as modern aircraft go, was an inefficient aircraft for airlines to run in terms of costs versus revenues. It was small and didn't hold many people or much cargo and burnt a lot of fuel (especially at supersonic speeds, but also at subsonic speeds), so passengers were basically paying first class prices to get between New York and London in half the time. Without the advantage of flying at supersonic speeds, the Concorde delivered all of the costs without any of the benefits of flying a normal plane. Military jets do not use the same cost/benefit ratio. The military isn't out there to make money off of their flights, they're out there to train their pilots in case of a war. They've got a budget to spend on fuel and they aren't looking to recoup those costs in other ways, so they'll fly wherever their commanders think it is important for them to fly. Regarding question 2, I can't answer that as authoritatively but I'm willing to speculate. I expect that 60,000 feet is the operational ceiling of the Concorde at which point the air becomes too thin for the engines to operate normally. For instance, a Bombadier CRJ-200 has a rated operational limit of around 40,000 feet above sea level, and [when pilots aren't careful flying above that limit bad things can happen.]( URL_0 ) It's not so much that the sonic boom would break windows below 60,000 feet as that the noise pollution was undesireable and being at higher altitudes dispersed the sonic booms across more area thus reducing the overall noise that reached the ground. [Mythbusters did an episode on sonic booms and were only able to break a window with a military jet's sonic boom when flying at 200' above the ground.]( URL_1 )",
"Additionally with what others have stated, the larger the aircraft the more energy it takes to push it faster and past the sound barrier. This translates to a larger shockwave. The Concorde was huge compared to modern supersonic military aircraft, larger even than the largest active supersonic bomber the B-1b Lancer. Higher altitudes do mitigate the effects of a sonic boom but there is a limit to how high planes can fly effectively. 60,000 feet is pretty high already. Not many aircraft make a habit of flying higher than that. Military reconnaissance aircraft like the U-2 and SR-71 could travel that high and higher but lots of design problems arise when you want to fly that high. As you go higher in altitude your wings become less effective and it becomes harder for the engines to breath. It requires special considerations and trade offs to design a plane that routinely flies that high. For example, the U-2 is not a particularly fast aircraft but its wings have an insane aspect ratio making it behave more like a glider than a plane in order to generate lift at those heights. Even with specially designed wings, the plane has to struggle to maintain enough speed to keep those wings working. The SR-71 flew much much faster and as a result didnt have to have as much consideration on basic wing design but since it flew amazingly fast other considerations like material expansion came up that was a whole different head ache. Also while sonic booms are mitigated by altitude, how effective is it really? A sonic boom doesnt have to shatter windows to be disruptive to society and annoying. A sound powerful enough to shatter windows at lower altitudes will still be stupidly loud at higher altitudes."
],
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"https://en.wikipedia.org/wiki/Pinnacle_Airlines_Flight_3701",
"https://military.id.me/aircraft/can-a-sonic-boom-break-glass/"
],
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| [
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5vu7hm | What makes instant noodles instant? | Why can they cook instantly in boiling water whereas my spaghetti needs to sit on the stove for more than 5 minutes before it's cooked? | Other | explainlikeimfive | {
"a_id": [
"de4whso"
],
"text": [
"They're already cooked and just need to be rehydrated. Think like a chicken breast...You can boil it and it'll take 20 minutes to cook, but if it's already cooked you just need to warm it through and it takes 5...Same concept different medium."
],
"score": [
4
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5vu9on | How possible is it with today's technology to cryogenically preserve and revive a human? | I've always been interested in being cryogenically frozen when I die. I'm wondering what the odds are if someone were to die and get frozen right now of them coming back later. I'm assuming not very good. Where are we predicted to be at in 10 years? Or 100? Is it fundamentally impossible to revive someone who has died by preserving them? Also, what needs to be improved more, the preservation process, or the resurrection process? | Biology | explainlikeimfive | {
"a_id": [
"de4wsjz"
],
"text": [
"Not at all possible. There is currently a 0% chance of a successful revival after being cryogenically frozen. The technology just doesn't exist yet, if it ever will. It's impossible to predict when it might. There are levels of science involved we still have no idea how to overcome, such as the formation of ice crystals in cells. There might be a breakthrough in 10 years, or never."
],
"score": [
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