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29ofup | why is spanish the only language that uses upside down exclamation and question marks? | explainlikeimfive | http://www.reddit.com/r/explainlikeimfive/comments/29ofup/eli5why_is_spanish_the_only_language_that_uses/ | {
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"Because....it just is. It wasn't all that long ago that it became \"official\" in spanish (it also used in catalan, I believe) - I've read old spanish text that does not use it from the early 1700s. \n\nI think it's pretty nice - knowing at the start of the sentence that you're reading a question is pretty handy.",
"In Spanish, unlike English, questions and statements are often worded identically. For example consider, \"You like apples\" versus \"Do you like apples\". Even without punctuation, you can tell the first sentence is a statement and the second sentence is a question. In Spanish, both the statement and question would be worded as \"Te gustan manzanas\".\n\nHaving the inverted question mark at the beginning alerts the reader that it is a question, whereas, in English, the reader is alerted by the word \"Do\" at the beginning. Obviously, in speech, you *could* ask the question \"You like apples?\", but this is rarer, and so isn't much of a problem.\n\nHowever, another difference is that Spain has the *Real Academia Española* (RAE). This is an official royal institution that oversees the Spanish language. That is, they actually decide what is and isn't proper Spanish. [In 1754](_URL_0_) the RAE recommended the use of the inverted question mark at the beginning of questions, and the use of the inverted exclamation point for exclamatory sentences. According to the Wikipedia page, short unambiguous questions often do not use the inverted question mark. \n\nEnglish, has no equivalent to the RAE. So even if some people thought the inverted question mark was useful for English, the only way it would become \"official\" is if it became fashionable/popular to do so.\n\nEdit: punctuation (ha)",
"When you're reading, you can tell long before the end of a sentence whether you're dealing with a question or an exclamation. "
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78h49w | how is autism treated? | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/78h49w/eli5_how_is_autism_treated/ | {
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"You don't treat autism.\n\n\nYou learn to live and function around it. It's not something that can be corrected. Less severe forms on the spectrum are easier to deal with than the forms that are more severe.",
"1. Autism is not a single disease. It is a name for a \"spectrum\" of disorders that present with a diverse but recognizably similar set of symptoms. But it's not what causes most of them, let alone if they have similar causes. \n\n2. Most disorders located on the \"autism spectrum\" aren't \"treated\" nearly so much as \"managed\". There isn't any real \"treatment\" for neurodevelopmental disorders the way there is for, say, bacterial infections, or even cancer. When the body doesn't develop the way it's supposed to, there's often not a lot that can be done about it beyond trying to mitigate the symptoms. \n\n3. Autism spectrum disorders are mostly managed with a combination of special education and behavioral/occupational therapy. The goal is less making the symptoms go away, and more helping the person live with and take charge of those symptoms. \n\n4. In this context, \"ABA\" probably refers to \"applied behavior analysis\". There's a detailed [Wikipedia article](_URL_0_) on the subject. TL;DR: it's a clinical way of trying to understand *what* a person is doing (it's not always as obvious as it sounds!), *why* they're doing it, and *how* to get them to replace a specific undesirable behavior with a desirable one. ",
"speaking as an autistic person, ABA is a cruel \"treatment\" method so-called professionals use that often causes distress to autistic individuals that they have to deal with for the rest of their lives. it discourages perfectly natural stimming behaviors because neurotypicals find them \"unacceptable\"-- doctors will often restrict childrens' hands to their sides for an extended period of time to keep them from flapping, for example, or force them to endure awful tastes to stop chewing. it's unnecessary and enforces the idea that we need to change to fit in to society rather than society doing the tiniest bit of legwork to accommodate us."
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2zssja | why do people get the urge to hurt young children out of affection? i.e. "he's so cute, i just want to bite/pinch/squeeze him" | explainlikeimfive | http://www.reddit.com/r/explainlikeimfive/comments/2zssja/eli5_why_do_people_get_the_urge_to_hurt_young/ | {
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"Does it go back to animalistic urges in regards to the care of our children that evolution tried to remove? ",
"I get this way about my cats sometimes, mom said she felt the same sometimes, so I've been wondering this same thing for a while :/",
"This is called \"cute aggression\". It seems to be a way of our brains regulating extreme emotions and restoring emotional equilibrium (similar to spontaneous laughter during a tragedy).\n\n_URL_0_"
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b55zcx | why do helicopters seem to make a rapid "popping" sound when flying overhead but a propeller airplane doesn't? | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/b55zcx/eli5_why_do_helicopters_seem_to_make_a_rapid/ | {
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"There are two main reason why helicopters make the popping noise. \n1) Unlike airplanes, helicopter blades often enter turbulent air that has been chopped by a blade before. \nThe blade entering this turbulent area causes a pop. \nAirplane propellers are pushed forward out of the area, helicopters tend to linger more in this area. Also planes that have two or more sets of propellers in front of each other tend to be really really loud, but don't sound like a pop pop noise because the propellers are spinning really fast (if they could afford to spin slower, they'd just make one prop and spin it fast). \n2) The second reason is that there's often a tail rotor. So that one has blades spinning into the turbulent air,this one coming down from main rotor down to it's side. It's chopping up the air stream coming down and making it go to the side. \nSeveral companies either surround the tail rotor with a cover from the top, or redirect air from other places and push it out the side. This reduces the noise greatly."
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e2gxmv | how are we able to see planets that are 100’s of lightyears away? by continually increasing the magnification of a telescope? how do we know anything about the planets atmosphere if it’s that far away? for example, the corot-7b, we are told it rains rocks there. | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/e2gxmv/eli5_how_are_we_able_to_see_planets_that_are_100s/ | {
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"We’re not able to see them.\nWe see them block the light from their star.\nOr we see their gravity tugging on their star.\n\nWe know about their atmosphere because when they block that star, some light pass through the atmosphere, which filters out some light but not others.",
"We don't actually see them. When the plant passes in front of its star, it blocks some of the sunlight. We see the sunlight dim in a very predictable way. By doing some calculation we can figure out the size of the planet and how far it is from its star. \n\nWe can tell the chemistry of the atmosphere by looking at the light. By using a prism, we can tell what the Star is made of. And then, when the planet first starts to pass in front of the star some of this light passes through its atmosphere. By using a prism and comparing the changes in the light we can tell what the planets atmosphere is made of. Imagine looking at a flashlight at night, and then looking at it when there is smoke in front of it. It changes right?",
"The most common method is by watching the host star's output for telltale signs of variation in it's brightness and position. A star that wobbles a small fraction tells you that there is some other body's gravity acting on it. This is done by watching a star's spectral lines as they change because a star and it's planet(s) will orbit a common center of mass. A star that moves away from you will have it's spectral lines shift red, and then blue as it comes toward you. \n\nAdditionally if a star dims a small fraction on a periodic basis, then that means an orbital body has moved across it from our perspective. \n\nThe size and mass of a star is determined first by watching binary stars. If you determine the size of their orbits around each other and the period (speed) of their orbits, then you can calculate their respective mass as well. Once you know the mass of a pair of binary stars you can apply that knowledge to similar stars not in binary systems. (And the more binary systems you study, the larger the range of single stars you can size)\n\nOnce you know the size of the individual star, you can calculate the mass of the orbital body and it's orbit by the parents star wobble and changes in luminosity. \n\nWhat the planet is made up of can be seen in general terms from watching the transmission spectrum coming from the system, and the spectral lines will tell you what materials are present.",
"A Prism is how we can see what something is made of \n\nSimply put, you shine light through a prism and it reveals a spectrum of light waves. Based on the wave, you can determine the element present\n\nELI5 version:\n\nYou send 118 people into a muddy room, all with different shoes. No matter how far the muddy room is from you, you can tell who has been in the room because evereyone has different shoes, and there are different shoeprints in the room.",
"We cannot see them, we can see a spot of light of unknown size. That spot could get dimmer and brighter, we can measure that, and calculate the size of a planet passing it, or if it's multiple planets, etc.\n\nWe can measure the star wobbling because it's relative velocity to us changes and we see a color change from that, we can calculate if a planet is causing this.\n\nAnd in some cases we can even measure light that came from a non-star and determine that it's a planet. The plant is lit up by the star, and bounces off the planet to us, we get the light, but we can't differentiate position of the planet from the star. What we can see is that the color of the planet is periodically added to the stars light and then not added, so we again see a change in color of the star, and we can determine that this is due to a planet, and the color of the planet (which we can use to tell if it has water on it or something)"
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6003mv | why is microwaving fish so stinky? | What is in fish that makes it so nasty and stinky to be microwaved? Does it have a different composition compared to other foods that cause such an awful odor when cooked in a microwave?
Edit: I'm not completely sure if this is a Biology or Chemistry question. Obviously, make up of fish is biology, but cooking is chemistry. I'll keep it at Biology with a probable Chemistry answer. | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/6003mv/eli5_why_is_microwaving_fish_so_stinky/ | {
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"Not a biology expert, but I don't think it's that the smell is \"bad\", necessarily, depending on what you're cooking. Fish smell just tends to stick even when it's freshly cooked. If you try some fish, the entire house will smell like fish for hours after. What's left behind isn't the tasty fried fish smell, but the actual \"fish\" smell, if that makes sense."
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3im8qo | how do people take videos without getting the "wind noise" in the background? | [deleted] | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/3im8qo/eli5how_do_people_take_videos_without_getting_the/ | {
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"They either spend time and money re-dubbing the sound afterwards in a studio or they simply use professional quality windshields on the microphones. The requirement is to create a region of still air around the mic, and that requires a large and cumbersome windshield and mount with space inside, rather than just a piece of foam that touches the mic itself.\n\nThe world leaders in the technology are a small British company called Rycote, who developed the large \"zeppelin\" shaped mounts and windshields and then further refined them with hairy covers to produce the well-known \"furry dog on a stick\" microphones you see being dangled over people. (Like these... _URL_0_)\n\nAll you could wish to know, here: _URL_1_\n\n(I have no connection with the company, just a satisfied customer)",
"That fluff or foam you see on professional microphones acts as a wind cover which can help break up the wind and prevent it from interfering with a recording. Later on residual noise can be removed using a software filter."
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8svjo9 | how farmers sell their crops | I've sold show steers to commercial butchers and stockyards. Is there some equivalent for produce and grain growers that isnt a farmers market? | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/8svjo9/eli5_how_farmers_sell_their_crops/ | {
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"There are grain brokers companies like ADM. Farmers bring their grain to a centralized silo and sell what they have. The broker company then sells it to... I’m not really sure who, but basically there are large commercial companies that own grain silos and will buy direct from farmers. "
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1v79g0 | how is it that so many people lacking teaching skills are hired as teachers/professors? | From my personal experience about 10% of my teachers are good at teaching.
And yet 99% of them know information applicable to that field.
You normally wouldn't hire a programmer that knows how to write code but can't write good code when it is needed. So why is it professors get away with it?
To expand, the professors bad at teaching couldn't explain fully why something was the way it was. Though if you asked them to solve a question/problem in their related field, they could do it effectively and efficiently. Their job isn't to solve the problems though, their job is to communicate the information in a memorable way so that their students aren't tempted to memorize information but rather think about it deeply and make connections.
So far my only fix for having a bad teacher is going on youtube and watching videos on the related section. Though this defeated the purpose of going to class and listening to a professor read directly out of the textbook for an hour or more.. If most teachers are simply read aloud text books, why don't school simply replace them with textbook reading software and a google/youtube search?
Does anyone know ways of getting through a class with a bad teacher/professor who is bad at teaching?
I can edit this if it isn't clear enough.
| explainlikeimfive | http://www.reddit.com/r/explainlikeimfive/comments/1v79g0/eli5_how_is_it_that_so_many_people_lacking/ | {
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"Professors aren't just teachers, but professional researchers.\n\nOnce you get far enough along in your field, the only people who know anything are those directly involved. They have not necessarily taken the time to make it digestible. They have two jobs, one of which is teaching. The other is staying on the cutting edge of your field by constant research and publishing papers from their University's press. So they may be one of the few people in the world even remotely capable of commentary on certain subjects; and there's no option to hire the 'better teacher'. So in their advanced level courses, they may be the only person for the job. But for the few intermediate level courses they've been stuck with this semester . . . yeah they're as excited about it as you are."
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bbwl4m | why do people have 'a drink' when having conversations? | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/bbwl4m/eli5_why_do_people_have_a_drink_when_having/ | {
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"Psychological analgesia. It makes one more comfortable and lowers the stress of small talk. Plus it opens the door to share a vice and bond over getting blind drunk together after business is settled.",
"You're talking about in the business setting?",
"It’s the same reason why you give or ask a guest in your home if they want coffee, water, soda. Some people like to give drinks."
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16ki44 | what is the difference between an lp and vinyl? and why are they considered to be better than a cd? | My Dad's giving me his old Sony HiFi system complete with record player, CD player, FM Radio and tape player/mixer (and external audio outputs that require adapters for my TV and Xbox). I'm considering investing in analogue formats for the record player if they're better value for money than CDs or MP3s. | explainlikeimfive | http://www.reddit.com/r/explainlikeimfive/comments/16ki44/eli5_what_is_the_difference_between_an_lp_and/ | {
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"Vinyl is the material that all records are made of. LP stands for \"Long Player,\" a hangover from the days when all records were on vinyl. What we now call albums were called LPs, because they had a long playing time. You also got singles (one track on each side) and EPs (Extended Plays, longer than a single, not as long as an LP).\n\nThey are considered to be better because of nostalgia, mainly. People like the pops and crackles that vinyl produces. But it's a *purely subjective* thing. There's no scientific reason why vinyl sounds better, and plenty of scientific reasons why CDs sound better. But people, including me, still buy vinyl.\n\nI haven't listened to a CD in about 7 years. Most of my digital music these days is on Spotify or iTunes. But I still buy vinyl. Why? Mostly for the artwork, and because I like how a big vinyl collection looks in my living room. But also, putting on a vinyl record feels more like an event than listening at the computer. When I put on vinyl, I'll sit and just listen to it. When I listen to Spotify, it's usually as background music to Reddit or whatever else I'm doing.\n\nAlso, it's much easier to skin up on an LP sleeve than on a CD tray ;)"
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8792fb | what is the difference between testosterone levels and libido levels in men? | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/8792fb/eli5_what_is_the_difference_between_testosterone/ | {
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"Testosterone is an actual hormone, libido is just a term for sex drive, not something actually quantifiable, and is a result of a number of factors, including but by no means only because of testosterone levels."
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39t1qd | how come people in rvs don't have to wear seat belts? | explainlikeimfive | http://www.reddit.com/r/explainlikeimfive/comments/39t1qd/eli5_how_come_people_in_rvs_dont_have_to_wear/ | {
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"In a crash, the thing that kills you rapid deceleration; the car stop moving but your body doesn't. This can worst-case scenario result in you getting thrown from the car, or at the very least smash into the console or seat in front of you. Seatbelts exist to hold you to your seat, so that, in the event of a rapid deceleration, you don't smash into something. \n\nRVs have a *ton* of mass. As such, they have a ton of inertia. In the event of a collision, the RV probably won't decelerate quickly enough to hurt you much (unless you literally crash into a wall of solid concrete or something). It's the same reason you don't need a seatbelt on buses. "
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2au1i8 | why don't we have people such as mozart or da vinci in modern times? | explainlikeimfive | http://www.reddit.com/r/explainlikeimfive/comments/2au1i8/eli5_why_dont_we_have_people_such_as_mozart_or_da/ | {
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"We do, they're called the Beatles :P\n\nKeep in mind that people like Mozart aren't just famous, they're remembered. We've probably already produced a few Mozarts, but we might only see them as such in retrospect. ",
"We may very well have. There are great composers, artists, actors, and such today, some of my favorites are still alive! \nHowever most of them don't get really famous until after they die (much in the case of Vincent Van Gogh). And between the examples you listed, Da Vinci and Mozart, there are a coupe hundred years from when they lived.\nGenerally to become \"History-book\" famous for the arts, or anywhere, you have to be a pioneer in your field. Mozart perfected and created many styles of music. Da Vinci created some of the most known pieces of art in the world, he even had ideas for an early version of a helicopter.",
"We don't??\n\nI am a learner of Indian Classical Music. Some of the maestros in this field have been practicing for more than 50 years. What they play is an intricate masterpiece of improvisation, knowledge of beat cycles, and awesome mathematical combinations of tunes and beats to create beautiful melodies. Even the percussionist modifies his playing in tune with the main performer often syncing with him perfectly, making it seem as a beautiful merger of two minds. People like Hariprasad Chaurasia, Shivkumar Sharma, Ravishankar, Zakir Hussain are considered as maestros in playing Flute, Santoor, Sitar, Tabla respectively. These folks are heavily popular and respected in India, both as musicians and as people. I have personally met 3 of them for taking their interviews, and they are very humble and down to earth, unlikely for a person who is among the most popular figures in your country. \n\nIndian music is not rigid, it is based on improvisation. One performance can last for hours and hours. The players never write down their creations, and often, one performance has many little bits of beautiful improvisations which can become individual symphonies in their own right, if written down. It is a vast arena, and seasoned players often say that one lifetime isn't enough to explore all the music there is. The fact that they are not as popular throughout the world doesn't reduce their skill and achievements in 'understanding' and creating music. Great people are defined less by their own skills, and more by the way their skills resonate with people's expectations and beliefs about them. On a test audience who is given to listen a track without being told it is composed by Mozart, less people will say they like it than people who knew it was by Mozart.\n\n**Tl;Dr: 'Greatness' of people is independent of their talent, it depends more on how much they impress us.**",
"I guess you could say that we have more people such as Mozart or Da Vinci nowadays contributing to each and every one of societal and scientific fields."
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64he1c | why do soap products create bubbles? do bubbles even do anything for you? | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/64he1c/eli5_why_do_soap_products_create_bubbles_do/ | {
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"Bubbles are a natural property of soapy water, but the bubbles don't do much for the actual cleaning.\n\nMany detergents do *not* naturally bubble (foam), but a foaming agent is added to the ingredients because consumers expect to see some foam to confirm that something is there.",
"normally oil and water hate eachother because the molecules that make them up are polarized oppositely. \n\nSurfactants, an \"anti-surface\", are things that align their polarity so that they attract. \n\nsoap is a surfactant: it stops water and oil from hating eachother, and also breaks down the surface tension of water- the way water molecules forms a \"skin\" because they attach so well to eachother.\n\nthe bubbles are an indicator that the surface tension's been broken down. Water can't bubble up normally until there's a surfactant present. Those bubbles are a nice indicator that now, that water can easily wash away bacteria, oil, and other gross shit. The better the surfactant, the better it can wash away oil and then you can rinse it all away.\n\nsometimes a surfactant is *so* strong and effective it'll strip all the oil from something, and if that is your hands and skin and hair, you'll have very dry hands/hair/etc, and if your skin is too dry for too long, it'll begin over-producing oil to compensate, and you get oily skin and hair.\n\nso to answer your question: The bubbles themselves don't do much but they indicate that what you're washing with is working and can get into little nooks and crannies and wash away dirt much better than non-soapy water."
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32qp57 | if someone with oral herpes opened a pack of cigarettes and spit and rubbed the contents of their mouth all over them and you smoked them a day later, can you get herpes? | explainlikeimfive | http://www.reddit.com/r/explainlikeimfive/comments/32qp57/eli5_if_someone_with_oral_herpes_opened_a_pack_of/ | {
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"No. Herpes dies really quickly outside the body. _URL_0_ has it at not much more than 10s. even under moist wet conditions."
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6fd3p9 | most ships have electricity onboard. do they have grounding cables? where does the electricity go? | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/6fd3p9/eli5_most_ships_have_electricity_onboard_do_they/ | {
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"Such boats either have a generator or batteries (for smaller ones). In either case it all works in a closed loop contained within the ship. There are no grounding cables much the same way there aren't any in cars or airplanes that have power outlets on board.",
"The concept of ground on a ship (or generically, marine use) is somewhat more complex than on land. First, the concept of *ground* is simply a common reference for zero volts. In the simple sense, it does not matter how this is established. In practice, especially on a marine vessel there are several things to consider. First, most large ships have both AC and DC circuits. All the DC circuits should have pos/neg directly connected, and never use a ground shared by AC. With AC, you will have a ground bus (a large wire) that all the AC gear must be bonded (connected) to. Again, the idea is to get everything to a common zero-volt reference. No need to actually get them to a real \"ground\" like on land. There is also a \"lightning plate\" that is used on some ships to connect tall masts too..this plate is mounted under the boat...in the water. In some cases (esp. military) there are a lot of radios and RF gear on board, so those will be grounded in a separate circuit on their own. This keeps things like engine and lighting noise out of the radio. "
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5ver7j | what happens in your body at concerts when it feels like your heart is about to vibrate out of your chest when they hit super low bass notes? | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/5ver7j/eli5what_happens_in_your_body_at_concerts_when_it/ | {
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"Sound is effectively just waves of air moving at different speeds and sizes. While most of them are so small you can really only sense them with your ears, as you start to get really low, the waves start to get a lot bigger, to the point you can actually feel them. That feeling is the air physically vibrating your body, usually with what's called a ground sub. Some Front of House Engineers do this on purpose to get that \"concert feel\", and the wavelengths that do it best are actually below your threshold of hearing, in terms of pitch, but can be powerful enough to knock even a grown person over.",
"Sound is, quite simply, a wave of pressure traveling through a medium (typically through air or water). What you're feeling are very large (low-pitch bass) pressure waves flowing through the air and through you. Your chest has a lot of mass, therefore, will absorb a lot of the wave as it hits you compared to your ligaments. The more you absorb, the more you feel. These waves are literally jostling your insides!",
"That is infrasonics which are frequencies that hit your body like percussion waves and they are low enough in frequency that you feel as much as hear. Although in a rock concert situation it's more about the power than simply being a low note. \n\nFor instance firing a pistol also kicks you in the chest with the sound wave but that isn't an infrasonic sound, but it has infrasonics in it as it's noise IE a range of different frequencies. The lower the pitch the more energy it takes in order to make the sound travel. \n\nTo put it another way, high frequency sound are like feathers. It doesn't take much to make them float through the air. Lower notes are like bricks, you can make them fly through the air but it needs a lot more power to do so, and if you catch one in the chest, you're going to feel it. \n\nOr to coin another analogy, when it comes to light you have infrared which are like the bass notes of light, and you have ultraviolet, which are like the high frequency sounds of light. While the high frequency can carry a lot of energy, like xrays and UV light, the lower frequencies can carry a lot of power, like getting burned from standing too close to a bon fire and the infrared radiation actually burns you from the light. ",
"There was a study on correlation between low frequencies and the growth of bacteria in bloodstream/colon. I'm trying to find the source. "
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2manpn | what is the distinctive "cold" smell that i get every winter? | explainlikeimfive | http://www.reddit.com/r/explainlikeimfive/comments/2manpn/eli5_what_is_the_distinctive_cold_smell_that_i/ | {
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"Living in the south, I know what smell you're talking about. I think it's actually a lack of humidity you're \"smelling.\" ",
"People can smell rain. Which is plants up wind opening up to the rain.\n\nWonder if cold is microbes or something.",
"I always thought it was fireplaces... but that could've been something my mom told me as a kid so I'd stop asking so many damn questions. ",
"Hmm this is interesting. It seems to be that the \"cold\" smell is caused by a combination of things. According to these articles posted below the \"cold smell\" isn't as much a smell in and of itself but the absence of smell since our noses are less active in cold weather. Also this smell may be connected to cold air and the way it reacts with our very warm nerves while the air is warmed up to our body temp.\nSources:\n_URL_2_\n\n_URL_0_\n\n_URL_1_\n",
"I've heard that your sense of smell is heightened in humid conditions. Which is why farting in the shower/bath is much, much worse. It's also why the smell of \"rain\" is so awesome. It's because you can smell a little bit of everything a little bit better. Maybe the \"cold smell\" is just an absence of smell?\n\nEdit: word",
"I've heard it's actually the smell of ozone.. It's denser at colder temperatures and stuff. But you can only smell it given certain conditions (humidity, temperature change, etc) which is why you don't smell it all the time",
"Are we sure that this is actually a real smell and not a response from the brain?; like when you think about lemons and your mouth gets flooded with saliva? What if your mind projects this 'smell' when the cold dry air hits your mucous membranes and lungs? Cold be a nifty response to enhance your awareness of the environment you're in.\n\nI got nothing to back this up, just a thought.",
"Hypothesis: through the rest of the year you smell things like humidity in the air, cut grass, and pollen.\n\nIn the winter you do not smell these.",
"I remember asking my dad this question when I was about 7, I always thought it smelled like burning - only for my mate who was present to pipe up stating there's always a wee man somewhere lighting a fire to stay warm. I laughed too hard at that.",
"Hey op, also ask, \"What is that weird sound you hear if you stand on the chilliest of days and listen carefully.\" I've come up with a word for it, \"Vorbid.\" I have no idea what it is though. Sometimes it sounds like electricity, sometimes it sounds like some low tone oscillation, but I hear it every winter.",
"People are missing the point and saying that it's due to your nose being cold. No, if I'm warm and cozy inside, I can smell a difference in someone who just came from outside.",
"This reminds me of an astronauts AMA where he talked about space having a distinctive metallic smell, in the airlocks."
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9cb8u6 | why are russians white? if its because of melanin and sun exposure, then why are indigenous siberians in the same geographic areas brown? | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/9cb8u6/eli5_why_are_russians_white_if_its_because_of/ | {
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"Russian Slavs, Finns, Germans (and many other people with European heritage) are white for the most part. There are many different nationalities within Russia. Chinese, Mongols, Koreans, Kazakhs, Armenians, Japanese, Georgians, Ossetins, Turks, Tatars, Circassians & Azerbaijani and many others are among them. Source: traveled Russia & served in Russian military (got to know many people from around the country, like A LOT).\n\nOr it could just be that people you mention lead a life that involves being outside a lot. Hence the tan.",
"In addition to the other answers it may be useful to know where the name Russians comes from. The Rus were a Viking tribe while some of their number moved west the Rus moved east and south and eventually formed the state that would eventually become Russia they then mixed with other groups like the mongols.",
"So, before more answers roll in, I'll expand on the question. A hobby of mine is studying anthropology and sociology and human migration through history. The topic of Russia still puzzles me. Is the answer simply that Russians are Europeans that immigrated? If that's the case, then who were the indigenous people of Russia and when did the whites get there? It's just interesting to me that Russians are indistinguishable from Western Europeans even though they live in a part of the world where everyone else looks Asian/Middle Eastern/mongoloid. ",
"Ethnic Russians are native to the western part of Russia. The part that is generally considered to be geographically in Europe. Over the centuries Russia has conquered and settled in the parts to the north, east and south of that.\n\nVarious different native groups inhabited those areas. Some light skinned, some darker skinned. Some of these native groups have their own \"republics\" within Russia, although in many of those they are outnumbered by ethnic Russians who have settled there over the last few centuries.\n\nBear in mind some of these \"native\" groups have migrated from elsewhere over a thousand or so years ago. ",
"This comes from the migration pattern of people. _URL_0_\n\nBasically Humans left Africa and kept to the coast; easier to live at the coast. At that time there was only black humans. \n\nThe first groups eastward went to India, China, and Siberia. They also cross into Alaska and went south. Those are the Asian and Native Americans.\n\nHumans also followed the Mediterranean coast and that's how humans got into Europe and Scandinavian. \n\nAt some point there was a mutation around the black sea area; that's when white people came into existence. Which largely speaking is where Russia is today. \n\nNote: This is one of the theories on the migration of homo sapiens. ",
"Russians came from the west (modern Ukraine). Mongols came from the east. After many years Russians pushed back the Mongols and took the modern Russian territory. The modern “white” Russian people are European and the Asian looking people are descendants of mongols. \n\nActually Russia has a huge diversity of ethnicities coming from all over the continent. \n\n[This ](_URL_0_) crash course video is a very good 10 minutes summary of the main points of the early Russian history. ",
"Ghengis Khan’s Mongol empire conquered much of Russia, along with most of the Eurasian continent. 1 in 200 asian men are direct descendants of his. ",
"The modern Russian ethnicity was built through a very long process of migration, conquests, assimilation, and so on. What is usually thought of as \"ethnically Russian\" developed in Eastern Europe, between the lowest parts of Volga (near the Caspian Sea) and the Baltic, almost reaching modern day Finland. \n\nAt the time, there was no difference, ethnically or otherwise, between what we now know as Russians and Ukrainians, Belorussians, Poles, and so on. It was, more or less, a simple eastern Slav ethnicity, with the same culture and language. The difference came when you went too far south-west, where you'd get to the Yugoslavs - the southern Slavs. Even so, the language was so close that people from Novgorod could understand a lot of what someone from Belgrade would be saying.\n\nThe eastern ethnicity later split, partially because of religion (Western and Eastern Christian churches), causing the appearance of western Slavs, those we know as Poles, Czechs, Slovaks, and so on. \n\nNow, as to the skin color.\n\nThe Slav ethnicity is a bit of a mystery. We know for certain that it emerged in the 5th century, and the only prior mentions of it are vague and hard to judge properly. However, they are Europeans, and were driven east by Germanic and Celtic tribes, eventually settling in the areas they inhabit now - Czechia, Slovakia, Poland, Belarus, Ukraine, and parts of eastern Russia. That's where the fair skin comes from - Europe. \n\n*(The rest is more about ethnicity and culture than skin color)* However, eastern Slavs, and Russians most of all, have been exposed to many different cultures and ethnicities over the course of history. There was a regular migration from south-east to north-west (Caspian to Baltic, as I described earlier), which already exposed them to cultures of Scandinavians, Balts, Indo-Aryans, Caucasians, and so on. The migration went back and forth, and that is the cause of appearance of modern day variants of eastern Slavic ethnicities. The migration didn't truly stop, even with the emergence of states and princedoms. Even Tolstoy, in the 19th century, noticed that the Russian peasants migrate back and forth once a generation. \n\nThen there was the influence of the Tatar-Mongol conquerors. The princes of Rus' became vassals of the Horde, and as such the culture and the language were significantly changed. Mongols weren't savages - they were the ones that brought the ideas of commerce and power into Rus', and it is still reflected in the language. \n\nThe European influence is also hard to underestimate - there were times when all of the Russian elite spoke Polish (which was already quite different from Russian, and carried with it western sciences and philosophy), and then all the court spoke French. Peter the Great brought in words and ideas from Netherlands and England. As such, the Russian language and culture was shaped by influences from both the east and the west. \n\nAnother thing worth noting, is that there are two different words for \"Russian\" within the actual Russian language. One, \"roosskiy\", refers to the ethnicity. The other, \"rossiyskiy\", refers to state. Russian Empire for example, isn't something that is ethnically Russian, it is a Russian state. As such, Russia has a less nationality centered view. As an empire, it had to treat the conquered territories equally to its own, else it would suffer the fate of the British Empire. As communists, ethnicity and nationality went out the window, at least on paper, and egalitarian view was promoted. And as of now, all that still has an influence. Russia is a very diverse country, with republics like Tatarstan, a whole different ethnicity, being part of the Federation. \n\n___\n\nMost of the historical and cultural facts are taken from V. O. Kluchevsky's lectures, the rest is my own experience as a Russian and a history enthusiast.",
"Russia is massive and incorporates many different kinds of people. Moscow itself was established as a Viking trading settlement. So most white Russians have Scandinavian genetic roots.\nThere are many redheads and blonde people in Russia\n\nPlaces like Crimea were conquered and settled by the Mongols centuries ago.\n\nSiberian’s came up from China fairly recently and are still darker in skin color"
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ka4em | why do we get goosebumps when we hear/feel styrofoam rubbing against more styrofoam and nails scratching chalkboards? | explainlikeimfive | http://www.reddit.com/r/explainlikeimfive/comments/ka4em/eli5_why_do_we_get_goosebumps_when_we_hearfeel/ | {
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"Read the title...got goosebumps....wanted to find out why....no definite explanation yet?!\n\nEdit: 'comments' to 'explanation'\n",
"Also: cheap markers on paper. Uuuuuuugh.",
"I forget where I saw this, but someone theorized that those sounds recreate high pitch frequencies that may have been used by early primates as warning/danger calls. ",
"When you get goosebumps, it's basically your body reacting to a fight or flight scenario. Your body will release a bunch of chemicals (including epinphrine and adrenaline) that cause your muscles attached to the hair follicles to tense, giving you goosebumps.\n\nWhen you hear styrofoam rubbing against styrofoam or nails on chalkboards it makes you feel uncomfortable. In a basic sense it triggers this sort of reaction in your body, even though there is no immediate danger. We haven't evolved to the point where we can ignore these types of triggers, and it is an involuntary reaction.",
"As far as I know, people don't actually know why this happens yet! At first that seems surprising, but really there are all kinds of things we don't know yet about the human body. It took millions of years of evolution to get us here, and we've only been studying it for maybe a couple thousand - there are still a lot of puzzles left to solve.\n\nThat said, people have made a few [guesses](_URL_0_), mostly by trying to find other things that make these kinds of sounds - such as crying babies, or even some kinds of monkeys. But scientists haven't come to a good agreement on these guesses yet though. People haven't spent much time working on answers to this question yet, so these guesses may be way off the mark. And in fact, most of this work was only done very recently - in the last five to ten years or so.\n\nPersonally, my favorite explanation has to do with [our teeth](_URL_1_) (I've marked the important bits in bold):\n\n > The answer came to me like a blinding flash. I was eating something at a picnic and I dropped it on the ground. I wiped it off and continued eating. (Oh, you do *SO* do it too!)\n > \n > As I was chewing, suddenly I heard SKKKKEEEEEERRRCH!!!!! ...as I bit down hard on a tiny stone. I think every single hair on my body stood on end, and my jaws froze instantly.\n > \n > THAT'S IT! Fingernails-on-blackboard: **It sounds exactly like the destruction of tooth enamel.** We're instinctively programmed to respond instantly. Of course! It's so sensible and obvious. Every little kid knows it. I remember many incidents from my own childhood. Why didn't we adults ever realize? The scraping of fingers on a blackboard is the classic, high-frequency violin-like waveform of hard dry surfaces moving with chaotic stick/slip motion. And that could very well be why our instincts are programmed to repond to it so strongly.\n > \n > **It's the sound of body damage; but it's a particular type of body damage for which there is no pain ...yet no healing.**\n > \n > We get no second chance with teeth. If we bite down on rocks, we wreck our enamel, and that could be why fingernails-on-blackboards makes everyone around us take drastic action to halt that noise. Why does nobody realize the origin of our response? We're too damned civilized, and we rarely have rocks in our food anymore. But whenever we bite down on something which is far harder than tooth enamel, our inborn programming instantly informs us about the problem in no uncertain terms. Sensible? Flesh can heal, but tooth surfaces do not.\n > \n > Skin is full of nerve endings, and pain normally teaches babies what not to do. The thick outer layer of our teeth lacks the pain sensors of other tissues. Won't animals need something besides pain to inform them that they're damaging themselves in a permanent way? Fingernails-on-blackboards could be entwined with evolution: Animals who respond strongly to that particular noise will guard their teeth carefully, and they won't ever bite down on rocks if they can possibly avoid it. **Animals who ignore that noise will die early from bad teeth.** We're the product of successful ancestors who CAN'T FREAKIN' STAND the loud internal sound of our own teeth scraping on rocks. And... hearing fingernails on chalkboard makes our teeth feel funny!\n\nThis guess hasn't really been properly tested out by scientists either though, but I think this makes a lot of sense - my teeth definitely tingle when I hear these sorts of sounds too. If we're lucky, we might know for sure in another five to ten years.\n\n_EDIT: So it turns out the author of the quoted text (written back in 2003) is also a redditor, and also subscribes to ELI5! It's such a small world. Reddit loves your theory [wbeaty](_URL_2_)! Please shower him liberally with upvotes._",
"I don't. It makes my teeth feel funny though.",
"I had no idea about the styrofoam thing, is that a commonly thought of nasty sound? I need to go try it now. I have never heard of this before.",
"One time I tried eating a salad out of a metal bowl. Everything was fine until I was nearly finished- I just couldn't stand to get the last bits with the fork scraping the edges of the metal. ARrrgG just thinking about it shrivels my face. Never again. ",
"Crumple up some aluminum foil, then brush it with a toothbrush.",
"I always thought that and silverware scraping on a plate is tied to visits to the dentist throughout my life. I figured I just react like a Pavlov dog to the sound. My mouth starts feeling weird and I get chills. ",
"Read the title...got goosebumps....wanted to find out why....no definite explanation yet?!\n\nEdit: 'comments' to 'explanation'\n",
"Also: cheap markers on paper. Uuuuuuugh.",
"I forget where I saw this, but someone theorized that those sounds recreate high pitch frequencies that may have been used by early primates as warning/danger calls. ",
"When you get goosebumps, it's basically your body reacting to a fight or flight scenario. Your body will release a bunch of chemicals (including epinphrine and adrenaline) that cause your muscles attached to the hair follicles to tense, giving you goosebumps.\n\nWhen you hear styrofoam rubbing against styrofoam or nails on chalkboards it makes you feel uncomfortable. In a basic sense it triggers this sort of reaction in your body, even though there is no immediate danger. We haven't evolved to the point where we can ignore these types of triggers, and it is an involuntary reaction.",
"As far as I know, people don't actually know why this happens yet! At first that seems surprising, but really there are all kinds of things we don't know yet about the human body. It took millions of years of evolution to get us here, and we've only been studying it for maybe a couple thousand - there are still a lot of puzzles left to solve.\n\nThat said, people have made a few [guesses](_URL_0_), mostly by trying to find other things that make these kinds of sounds - such as crying babies, or even some kinds of monkeys. But scientists haven't come to a good agreement on these guesses yet though. People haven't spent much time working on answers to this question yet, so these guesses may be way off the mark. And in fact, most of this work was only done very recently - in the last five to ten years or so.\n\nPersonally, my favorite explanation has to do with [our teeth](_URL_1_) (I've marked the important bits in bold):\n\n > The answer came to me like a blinding flash. I was eating something at a picnic and I dropped it on the ground. I wiped it off and continued eating. (Oh, you do *SO* do it too!)\n > \n > As I was chewing, suddenly I heard SKKKKEEEEEERRRCH!!!!! ...as I bit down hard on a tiny stone. I think every single hair on my body stood on end, and my jaws froze instantly.\n > \n > THAT'S IT! Fingernails-on-blackboard: **It sounds exactly like the destruction of tooth enamel.** We're instinctively programmed to respond instantly. Of course! It's so sensible and obvious. Every little kid knows it. I remember many incidents from my own childhood. Why didn't we adults ever realize? The scraping of fingers on a blackboard is the classic, high-frequency violin-like waveform of hard dry surfaces moving with chaotic stick/slip motion. And that could very well be why our instincts are programmed to repond to it so strongly.\n > \n > **It's the sound of body damage; but it's a particular type of body damage for which there is no pain ...yet no healing.**\n > \n > We get no second chance with teeth. If we bite down on rocks, we wreck our enamel, and that could be why fingernails-on-blackboards makes everyone around us take drastic action to halt that noise. Why does nobody realize the origin of our response? We're too damned civilized, and we rarely have rocks in our food anymore. But whenever we bite down on something which is far harder than tooth enamel, our inborn programming instantly informs us about the problem in no uncertain terms. Sensible? Flesh can heal, but tooth surfaces do not.\n > \n > Skin is full of nerve endings, and pain normally teaches babies what not to do. The thick outer layer of our teeth lacks the pain sensors of other tissues. Won't animals need something besides pain to inform them that they're damaging themselves in a permanent way? Fingernails-on-blackboards could be entwined with evolution: Animals who respond strongly to that particular noise will guard their teeth carefully, and they won't ever bite down on rocks if they can possibly avoid it. **Animals who ignore that noise will die early from bad teeth.** We're the product of successful ancestors who CAN'T FREAKIN' STAND the loud internal sound of our own teeth scraping on rocks. And... hearing fingernails on chalkboard makes our teeth feel funny!\n\nThis guess hasn't really been properly tested out by scientists either though, but I think this makes a lot of sense - my teeth definitely tingle when I hear these sorts of sounds too. If we're lucky, we might know for sure in another five to ten years.\n\n_EDIT: So it turns out the author of the quoted text (written back in 2003) is also a redditor, and also subscribes to ELI5! It's such a small world. Reddit loves your theory [wbeaty](_URL_2_)! Please shower him liberally with upvotes._",
"I don't. It makes my teeth feel funny though.",
"I had no idea about the styrofoam thing, is that a commonly thought of nasty sound? I need to go try it now. I have never heard of this before.",
"One time I tried eating a salad out of a metal bowl. Everything was fine until I was nearly finished- I just couldn't stand to get the last bits with the fork scraping the edges of the metal. ARrrgG just thinking about it shrivels my face. Never again. ",
"Crumple up some aluminum foil, then brush it with a toothbrush.",
"I always thought that and silverware scraping on a plate is tied to visits to the dentist throughout my life. I figured I just react like a Pavlov dog to the sound. My mouth starts feeling weird and I get chills. "
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8yo6jg | can small things see smaller things that we can’t see with our naked eye because they’re smaller? | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/8yo6jg/eli5_can_small_things_see_smaller_things_that_we/ | {
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"Small eyes have fewer number of sensory cells, so the resolution of the image they produce is far worse. Ants probably can't see microscopic organisms, but they can see what's relatively similar to their own size."
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7hp3iv | why is it that when you're cutting something in a sawing motion back and forth, it is easier to cut then just pushing down? | You're applying the same downward pressure both times but it is significantly easier to saw something. This is especially true with serrated blades. | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/7hp3iv/eli5_why_is_it_that_when_youre_cutting_something/ | {
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"A knife has very tiny teeth on its cutting blade. They are just natural imperfections in the metal. They are small enough that you can't see them without a microscope but large enough to act as a saw.",
"Mechanical engineering student here.\n\nWhen you're splitting something you're basically separating the microscopic adjacent layers that the object has into two parts.\n \nWhen you're sawing you're actually removing a layer bit by bit. The thickness of the removed layer is equal to the thickness of the sawblade. \n\nThis is why when you saw a wooden log, you have some sawdust leftover. The sawdust is simply the amount of wood that was removed during the process. However, splitting the log with an axe doesn't leave remains.\n\nNow the next question is: what's the difference between removing a layer bit by bit and splitting two adjacent layers? \n\nI can't really tell you I'm afraid. That sounds to me like non-trivial materials engineering. I'm pretty sure it does have something to do with the direction that you're applying the force in.",
"Friction over force...\nWhen you saw you allow smaller sections to seperate simultaneously where as pushing force your trying to stretch the whole thing...\nA larger more exaggerated example to illustrate this would be grating cheese or just trying to force it through the holes...",
"It depends. You have two things going on here, material and blade. Assuming that you arent using a serrated blade, here is what's going on. First: With something more soft or flimsy like rope, ribbon, cardboard, tomatoes, etc IF you are using a very sharp blade it will push through. However if the blade is not very sharp, sometimes the softer material will bunch and try to crush and deform rather than cut. When you apply a sawing motion, you are effectively applying a cutting force at multiple angles allowing the force to cut two ways rather than one. This makes it less likely that the material will bunch, squish, deform, etc. More firm material will still cut better with a push cut ( think of sharpening a pencil or whittling a stick or slicing a carrot) but with a lot more effort needed when using a dull blade. The second thing that is going on is the blade itself. If you were to look at a blade under magnification, a dull blade would look more like a saw. This is because you basically have microscopic burrs going in several directions, knicks, bends, overall rough and/ or folded over edge. Not only does this make the edge dull, it also makes the knife more saw like and makes a sawing motion almost necessary for some materials. When you sharpen and hone a blade, you are aligning those burrs, knocking off the little teeth, smoothing out and straightening the edge, which makes the blade much more sharp along the edge axis rather than having the edge material pointing in all directions, different heights, and all rough. This lets the material act as one unit (blade) rather than a saw (teeth) Hope this helped.\nThis article has some photos. _URL_0_\n",
"You can push a sharp needle into something easily because you have the whole force of your push concentrated into a tiny point. A saw is a series of tiny points. It will easily penetrate shallow into the material, just like a knife tip would.\n\nHowever, a knife needs to split the material to get deeper. It is resisted not only by the material directly affected but also by the parts adjacent to it that get compressed. You have to put a knife into the piece being cut and the whole piece resists to being pressed. The volume of the material being cut now has to contain the same volume of the material and the volume of the knife being pressed into it. If it isn't compressible the knife can't come in. It may work for materials that are soft enough that the whole piece is deformed and the outer layers of it are moved wider. When you're cutting butter with a thick knife, the whole bar will \"swell\" in your hand.\n\nThink about it that way: it is very hard to put a knife into a piece of wood, even if it's relatively soft. It is not hard to cut a match in half, lengthwise, because the 2 splinters can separate easily without being pressed into the rest of the log and accommodate the thickness of the knife between them, even though a match is still the same wood.\n\nSaw doesn't pressure any part of the material it doesn't come into contact with. It cuts a tiny bit off, removes it and then cuts another bit. One tiny sliver at a time. The rest of the piece is unaffected.\n",
"There's a lot of answer here and many of them come really close without really getting to the gist of it. /u/stawek does a really good job and consider this an add-on to his.\n\nWhen you're slicing something (with say an axe), only the material in direct contact with the blade is being cut/cleaved whatever. Once you get through that, you cleave the next layer and so on and so forth. When you apply pressure with the blade, the layer deforms by bulging away from the blade. In a slice, the layer can't bulge much at all because there's more material behind it. As a result it pushes into your blade.\n\nWhen slicing, all the layers under the blade are pushing back at the saw at the same time, meaning the pressure from the blade is distributed across all those layers. This means you have to apply enough pressure to cut all the layers at once.\n\nSaws are different. Saw teeth are specifically designed to pull some material up away from the cut so that you can cleave it without having to worry about the material behind it resisting your cut. As a result, you only need to cut a tiny piece that's in contact with the blade, without having to worry about everything that's behind it. Also saw teeth are somewhat auto-correcting, in that if you're trying to cut too much at once, the teeth will move away from the cut until the material can be cleaved with the force you're applying."
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883h10 | how can online businesses like amazon collect state sales tax on sales but then not contribute to the states with the collected sales tax? | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/883h10/eli5_how_can_online_businesses_like_amazon/ | {
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"the problem here is with amazon's third party sellers. \n\namazon does collect sales tax in the 45 states they have a presence. the local/state gov't in those states do get paid. but only if the item is shipped and sold by amazon. \n\nif it's shipped and sold by a third part or fulfilled by amazon for a third party, then no sales tax is collected. \n\nthat's the beef. "
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9nmvcw | whats the point of me signing my copy of a receipt? | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/9nmvcw/eli5_whats_the_point_of_me_signing_my_copy_of_a/ | {
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"In most cases it's to initial that you received the money so you can't go back later and claim they forgot to give it to you.",
"Proof you got your cash. If you go back in saying they never gave it to you then they can show the proof of pickup."
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6fxt42 | how did romans tell the difference between iron pyrite and real gold? | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/6fxt42/eli5_how_did_romans_tell_the_difference_between/ | {
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"It's been known for thousands of years that gold is mostly inert. It's one of the reasons it was valuable, as gold now would still be gold in a thousand years, making it perfect for any application where you needed a material that lasts forever.\n\nPyrite, on the other hand, doesn't have this property. Therefore, the test was to drip a bit of acid on the metal in question. If nothing happened, it was gold. If it began to bubble or change color, it wasn't.",
"Weight, flammabilty and of course one thing: try to melt or smith pyrite. You'll only smash it to pieces.",
"* Pyrite can scratch copper or glass but gold can't\n* Pyrite crumbles under pressure but gold merely dents, so you can push a hard point against it and see which one happens\n* If you rub it on a rough surface, pyrite will leave a green or black mark. Gold will leave a light streak of gold\n\n ",
"They had dark stones called touchstones they could rub the sample they were testing across. If it was a soft metal, the sample drew a line on the stone. Pyrite wouldn't. \n\nThey could tell the metal of the sample by the color of the line, and they kept touchstones with lines drawn by samples of known purity around for comparison, so they could figure how pure the sample they were testing was. \n\nTouchstones allowed them to test for the purity of gold, silver, copper, tin, and lead.",
"just burn it. gold won't burn, it'll just melt. iron sulfide will react and become iron and sulfur.\n\n_URL_0_"
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45qhto | what is the maximum number of gps devices that the network can support? | And what is the limiting factor? Hardware of satellites, number of frequencies or something else?
Edit: thanks for answers. I feel kind of stupid now. | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/45qhto/eli5_what_is_the_maximum_number_of_gps_devices/ | {
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"GPS is a passive system, there's no two-way communication with a GPS receiver and the satellite. The satellites simply blindly broadcast the necessary information and a receiver picks up these transmissions and uses it to calculate it's position based on the relative time difference between the different satellites it sees, since the signal takes slightly different amounts of time to arrive from the different satellites at different distances. Since the receiver is passive there's no limit on the number of devices. See [this wiki article](_URL_0_) for more information",
"How many GPS devices can you build? \n\nGPS is a one way communication. There are around 30 GPS satellites orbiting the earth, and no matter where you are there are always 4 of them in viewing range (Barring places that obstruct the sky like caverns or large mountains).\n\n.\n\nGPS works as followed: A gps device will search for and latch onto the signal of 3 satellites (in the meaning it will start listening). The sattilites will constantly send out time stamps via radio waves to whoever cares to listen. the device will use the time taken for the message to arrive to calculate how far away the satellite is. when it has received signals from 3 satellites it can triangulate its position. (basically: draw three circles. the point where they all intersect is your position).\n\n.\n\nthere is no limit to how many devices can listen to each satellite. If I stand in the middle of a crowded market and start shouting into a megaphone there is no limit to how many can hear my voice if they are in hearing range. ",
"No limit. GPS is a set of satellites which transmit a specially designed radio signal. Receiving chip sets in phones and GPS devices merely detect their location by measuring the difference in timing between signals from different satellites. GPS devices do not transmit anything to a \"network\". ",
"There's no limit. GPS works by satellites sending out a carefully calibrated time, and the the receiver's job is to work out from the satellite and time info where it is relative to the satellites. The satellites don't receive any signals, so there's no limit to the number of GPS devices possible.",
"\nImagine like a radio. The broadcasting station doesn't receive anything from the people listening. They just send out the music/audio/whatever that they're playing, and people pick it up."
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avda7e | is lip reading possible for all languages? | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/avda7e/eli5_is_lip_reading_possible_for_all_languages/ | {
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"It goes without saying that it’s not possible for ASL and other languages that don’t use the lips, but otherwise, to a certain extent. \n\nLip reading isn’t 100% perfect for pretty much any language, because different sounds can be made with the same lip movements - your tongue and throat also play a role. Because of that, a lot of lip reading is educated guessing - contextually, only some of those sounds would make sense. If a language has a lot of similar movement words or common sounds, it’ll be more difficult to lip read in. ",
"i imagine it would be pretty difficult for chinese, as it's a tonal language and the meaning of the words change depending on what tone you use."
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9vcogz | why do you have to “return” an e-book from an online library service. why can’t you just download it if they’re already letting you read it for free whenever you want? | My library has an e-book service where you can ready any book they have in their catalog as an e-book. The only thing is, you have to “borrow” it, and then return it in 7 days. But as soon as you “return” the e-book you can just hit “borrow” again. So how is that any different than just letting the library users download the e-book and store it locally on their device? | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/9vcogz/eli5_why_do_you_have_to_return_an_ebook_from_an/ | {
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"Copyright and licensing. Same reason you can't just go to a library, take a book home, and photocopy every page so you have your own personal copy.",
"Because of licensing, they can only have so many users “check out” a book at a time. If they are only licensed for five copies of a book, the sixth person is out of luck until someone “returns” their copy.",
"I was also wondering about ebooks. Specifically when I want to check out a book at open _URL_0_, I have to go on a waitlist even though they are all ebooks. So I don't understand why more than one can't be checked out at a time",
"Others have already commented on the simulated-scarcity angle. I'll speak to the technical nature of how this works. \n\nThe file you download is encrypted such that it cannot be read without help. The software you use (sometimes an e-reader, sometimes Adobe Digital Editions, sometimes something else) looks up your account information and downloads a sort of helper file (certificate) that decrypts the file so that you can read the book. However, all of this depends on rules such as the time and date you checked out the book versus the time and date you're trying to read it, and how long you're allowed to have the book before it's due back. \n\nThe helper file contains a record of when you checked out the book and will only decrypt the file during the allowed checkout period. Once it expires, you do technically still have the e-book file. However, since it's encrypted and the reader software now refuses to decrypt it, you can't really do much with it. \n\nWhen you hit \"borrow\" again, you download a new helper certificate with a new time-and-date stamp that reflects the new checkout time and is good for another 7 days.\n\nThat said, there are plugins like DeDRM for Calibre that will capture the decrypted content and create a permanent readable file that will last forever, but that's outside the scope of your question.",
"I write ebooks for a living, and this is a question that comes up a lot. Basically it comes down to a simple issue: **Who pays the writers?**\n\nBooks don't just spring from the earth fully-formed; they're written, often over the course of months or years, and the people who work on them generally like to be compensated for their work; personally, I'm a *very* big fan of being able to pay rent and afford food. If you had a system wherein you could legally get access to books for free forever... well, why would anyone buy them? Why would anyone pay money for anything if you could, with no restrictions, walk into a bookshop and just grab a copy off the shelf to keep for yourself and no one would stop you or expect you to hand over any cash? The short answer is, they wouldn't.\n\nSo ebooks create an artificial scarcity. The authors are compensated when the book license is bought, but the license has some limitations on it: either it lasts for a certain amount of time (say, a year in which only one person can have that 'copy' of the book at a time), or it lasts for a certain number of borrows (say, twenty) before the author gets paid again."
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8vk4sz | what tells a transistor to turn on/off? | If a transistor works by stopping electrons with voltage, what applies the voltage to the transistor? | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/8vk4sz/eli5_what_tells_a_transistor_to_turn_onoff/ | {
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"The base (or gate for FETs) is the control terminal. Base current or gate voltage determines how hard the transistor conducts. It does not have to be only on or off, analog circuits use varying current. ",
"Whatever you want! \n\nThe voltage could come from a microphone or guitar pickup. These produce small voltages and low currents, so the switching effect can be used to make the audio signal louder, and eventually powerful enough to drive a speaker (usually with much more than 1 transistor used overall).\n\nAs I implied in that explanation, the voltage can also come *from another transistor* or related circuitry.\n\nAnother example is it could come from a computer (which is ultimately transistors but... let’s not worry about that) which can’t supply much voltage or current, just like the guitar pickup or microphone.\n\nThis lets the low-powered computer control high-powered things like motors or lights.\n\nNow, *inside* computers the signals that drive transistors almost always come from other transistors. The ways they’re wired together are a bit tricky, but the basic idea is simple. Imagine voltage (signal) from 2 separate transistors is needed to activate another one. Either one doesn’t provide enough voltage. Whether the third one turns on tells you if *both* the drivers have been activated, and this forms the basis of logic operations like “if x and y are both true, do z”. \n\nIf either or both of the first transistors can provide voltage to activate the third one, you can do logic like “if either x *or* y are both true, do z” "
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apdq2g | a cell splits to become 2 cells of equal size. at what point did the cell gain matter in the process? | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/apdq2g/eli5_a_cell_splits_to_become_2_cells_of_equal/ | {
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"It didn't. The two new cells are smaller than the one which split started out as. All of the requisite size gain happened before the split, and both can increase further in size afterwards.",
"It doesn't become 2 cells of equal size. The cell grows to the point that it's ready to split, it splits, and each new cell is half the size of the single cell, then they both grow until they're ready to split and it continues"
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mcptm | china's part in world war ii. | What was going on over there? | explainlikeimfive | http://www.reddit.com/r/explainlikeimfive/comments/mcptm/eli5_chinas_part_in_world_war_ii/ | {
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"The Eastern Front and Pacific Theater is often forgotten. [It's sad really.](_URL_0_)\n\nFrom the little I know, I believe China was in the middle of a civil war between a pretty facist dictatorship allied with the US and a communist rebellion that was losing. I believe that the China was also friendly with the Nazis in that there were German experts, engineers and civilians in China there to improve the country. Nazis, however, allied with Japan thinking they would start an Eastern front for the USSR (never happened, but Stalin was forced to have a lot of troops in Eastern USSR to prevent this from happening). \n\nJapan wanted more resources and really invaded in 1937 and pretty much bulldozed the areas in the north, but had harder more costly victories in Shanghai and then Nanking where they massacred and raped the general population and sacked everything. One Nazi, John Rabe, managed to setup a zone to protect some of the population. The Japanese also retaliated by bombing civilian targets in other cities. Guerrilla fighting continued as Chinese were pushed from the coast. Chinese in America urged America to join the war in the Pacific as many wanted the US to join the war against Hitler. China had some victories. Finally, the US joined after Pearl Harbor. Then US and sometimes joint Chinese/Viet/British/etc had more victories around the Pacific and from E. India north and east. \n\nIt's really hard to get accurate unbiased accounts of battles as there are few movies or stories or whatnot surrounding this. \n\nAfter China gained a seat as a veto member on the UN Security Council, but also continued the civil war. \n\nAlso, China and particularly Shanghai was the only country that allowed Jews in without permits or whatnot. This is when the US and others turned away ships of Jews. Not many European Jews took that up as China is really far, but many Middle Eastern Jews came. When Japan invaded, they were put in a ghetto. It was bad, but a lot better than Polish ghettos. When Hitler ordered Japanese to kill Jews, they postponed the order until the war was over. When the war was over, most went to the newly formed Israel and the rest left after the commies took over. ",
"The Eastern Front and Pacific Theater is often forgotten. [It's sad really.](_URL_0_)\n\nFrom the little I know, I believe China was in the middle of a civil war between a pretty facist dictatorship allied with the US and a communist rebellion that was losing. I believe that the China was also friendly with the Nazis in that there were German experts, engineers and civilians in China there to improve the country. Nazis, however, allied with Japan thinking they would start an Eastern front for the USSR (never happened, but Stalin was forced to have a lot of troops in Eastern USSR to prevent this from happening). \n\nJapan wanted more resources and really invaded in 1937 and pretty much bulldozed the areas in the north, but had harder more costly victories in Shanghai and then Nanking where they massacred and raped the general population and sacked everything. One Nazi, John Rabe, managed to setup a zone to protect some of the population. The Japanese also retaliated by bombing civilian targets in other cities. Guerrilla fighting continued as Chinese were pushed from the coast. Chinese in America urged America to join the war in the Pacific as many wanted the US to join the war against Hitler. China had some victories. Finally, the US joined after Pearl Harbor. Then US and sometimes joint Chinese/Viet/British/etc had more victories around the Pacific and from E. India north and east. \n\nIt's really hard to get accurate unbiased accounts of battles as there are few movies or stories or whatnot surrounding this. \n\nAfter China gained a seat as a veto member on the UN Security Council, but also continued the civil war. \n\nAlso, China and particularly Shanghai was the only country that allowed Jews in without permits or whatnot. This is when the US and others turned away ships of Jews. Not many European Jews took that up as China is really far, but many Middle Eastern Jews came. When Japan invaded, they were put in a ghetto. It was bad, but a lot better than Polish ghettos. When Hitler ordered Japanese to kill Jews, they postponed the order until the war was over. When the war was over, most went to the newly formed Israel and the rest left after the commies took over. "
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4yyuf9 | does the mass of the earth grow via the energy collected by plants or is the biosphere a closed recycling system? | Ignoring materials falling from space... | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/4yyuf9/eli5_does_the_mass_of_the_earth_grow_via_the/ | {
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"E = mc^2, so a lot of energy is needed to make just a little bit of mass. While the sun's light does give earth some tiny amount of mass-energy, the earth is also constantly radiating heat and other light into space. \n\nHowever the total contribution of mass-energy from light going in and out is (I would guess) likely dwarfed by the small amount of debris that earth picks up from space, in the form of micrometeorites and other tiny space rock/dust things that add a little bit of mass pretty much all of the time.\n\nThe biosphere is closed in the sense that it doesn't eject matter into space (with exceptions of rocket launches or asteroids knocking stuff up there, which are so rare and small that they hardly count) but energy is constantly flowing in and out in the form of light of various kinds."
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2vi6vw | how is it humane/okay to keep birds like bald eagles in zoos? they can't possibly have enough room to fly, right? | I can see keeping them in captivity for endangerment/breeding purposes. What's going on there? | explainlikeimfive | http://www.reddit.com/r/explainlikeimfive/comments/2vi6vw/eli5_how_is_it_humaneokay_to_keep_birds_like_bald/ | {
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"Most Eagles in captivity are rehab or unable to be reintroduced to the wild. \n\nAlso they are given lots of space to live sense they aren't establishing hunting territory they don't need as much space as in the wild, and birds of prey do live longer in captivity \n\n(I have dealt with my fair share of birds of prey) ",
"It's usually those that either can't fly or have some problem that would kill them in the wild.\n\nBirds don't actually need huge areas to survive. They need it to hunt the things in it, and since animals are so spaced out, they need massive territories to have enough to eat. When humans feed them, they don't need nearly as much space"
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12go96 | how is it possible that i was able to drive to work with the e-brake pulled on the car? | I borrowed my boyfriends car to get to work today, which has the lever type ebrake by the drivers seat. I'm used to the foot brake which is why I didn't notice until I was almost at work (yeah, yeah, bring on the woman driver jokes). How was the car able to keep moving forward and such if the brake was on? | explainlikeimfive | http://www.reddit.com/r/explainlikeimfive/comments/12go96/eli5_how_is_it_possible_that_i_was_able_to_drive/ | {
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"An \"e-brake\" is not, **NOT** an emergency brake. It wasn't put there to save you if your brakes fail. If your car, or braking system is in such a sorry state that you rely on this component to save you, you've got some bigger problems...\n\nWhat it is, is a parking brake. It's only meant to hold the weight of the car on a hill. That's why they rachet and need to be unlocked to release. If it were an emergency brake, this mechanism wouldn't be there.\n\nI have no idea how the name e-brake got stuck to the parking brake, but it did, and I've seen it in car manuals called such. Look in your car manual, it probably only talks about this brake in terms of parking, not emergencies.\n\nAnyway, if your car has drum brakes, this is simply a cable that runs from the handle to the rear tires. It works just like the brakes on a bicycle. It engages the brake pads against the drum. The brake pedal is part of a hydraulic system, and can apply enough force to stop a moving car.\n\nIf you have all around disc brakes, then the parking brake is attached to a hydraulic cylinder that applies a little bit of pressure. And this is why it's not an e-brake, because if your brake pedal fails, with this configuration, the e-brake is going to do precisely nothing more the pedal can.\n\nSome cars, probably specifically big pickup trucks, have a secondary brake system just for the parking brake. I've only seen mechanical versions of this with a cable.\n\n---\n\nLets say you do use this brake mechanism in the case of an emergency. What emergency, I can't really imagine. Lets say your brakes fail. Man, you're fucked. Usually you find out when you're doing +40mph and the semi in front of you comes to a stop, or a kid runs into the street. You step on the pedal and nothing happens. Now what? ::SMASH:: By the time you think about it, you've hit the whatever.\n\nBut lets say you pull the hand brake. What can you possibly expect? Well, these systems usualy only engage the back tires, which is only responsible for less than 20% of your breaking, as all the weight of the car shifts on the front tires.\n\nAt worst, the back tires lock up, and your car drags the back of the car for ~1/3 a mile, wearing huge flat spots into your tires. And yes, I'm still considering an initial speed of 40mph. At best, this gentle breaking pressure may slow the car down over a half mile or so, presuming you're not going down hill.\n\n---\n\nAs far as the car overcoming the breaking force? As I said, ~80% of the cars weight will go to the front tires, the rear does very little stopping. Further, your engine, even in a dinky little Smart, is plenty powerful enough to overcome the breaking force applied if you mash both pedals to the floor, and I'm talking about the normal break here.\n\n---\n\nAlso keep in mind that it's a good practice to use the parking break whenever you're parked. If you were to drive a manual car, there's no \"Park\" setting on the transmission, the car would roll away in the parking lot!\n\nFurther, \"Park\" on your transmission sets a pin into the gears, binding the gears, holding the car into place. I suppose it's fair to say breaking that pin doesn't happen often, but I've seen it. At best, the pin drops into the oil pan of the transmission, at worst, you call a tow truck, because you don't have a functioning transmission anymore.\n\nEvery time someone with an automatic parks on a hill, and they don't use the brake, I cringe as the car settles back (or forth), onto that pin. I pray it doesn't snap on them.",
"\"I rent a lot of cars, but I don't always know everything about them. So a lot of times, I drive for like ten miles with the emergency brake on. That doesn't say a lot for me, but it really doesn't say a lot for the emergency brake. It's really not an emergency brake, it's an emergency \"make the car smell funny\" lever.\" - Mitch Hedberg"
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btj5jk | what determines the type of batteries an electronic is assigned to? aaa, aa, the circle ones, etc | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/btj5jk/eli5_what_determines_the_type_of_batteries_an/ | {
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"They look at how much power the device needs to consume, and try to pick a battery big enough to power it for a conveniently long time, but small enough to avoid making the device too big/heavy.",
"Two factors are in play:\n\n1) The form factor of the device being powered.\n\n2) The power requirements of the device.\n\nAA, AAA, AAAA, C and D are all 1.5 volt regardless of their size. CR2032 (the circular button shaped battery) outputs 3V and 9V doesn’t need explanation.\n\nIf you have a remote control that requires 6V to power the electronics inside of it. You’ll need to use 4 A-D batteries (1.5V + 1.5V + 1.5V + 1.5V = 6V). D and C batteries are too big for remote controls, but A type batteries are just the right size. Whether the remote uses AA or AAA or AAAA depends on the shape of the remote, but it can be an arbitrary decision in many cases. If you are powering a flashlight, you might opt for C or D batteries since form-factor is less of an issue. Four D batteries in sequence will output 6V, just as four AA/AAA batteries do. However, because D batteries are bulkier they have more juice. This will makes them last longer inside a flashlight as opposed to 4 AAA batteries, which would also fit inside a flashlight and power it, but not for very long."
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9b6bh8 | why does fruit start to rot on room temperature, but can stay good for weeks in the fridge? | EDIT: Thanks a bunch guys! | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/9b6bh8/eli5_why_does_fruit_start_to_rot_on_room/ | {
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"Cold temperatures cause the growth of bacteria to slow down, almost to a halt in most cases. Those bacteria are then cooked away, or are only present in small enough amounts that they aren't harmful. When kept out of the fridge, the bacteria grows unheeded, and can cause rotting or cause someone to be sick if they eat it.",
"Fruits produce an enzyme that causes them to ripen. Refrigerating the fruit stops the production of that enzyme. At room temperature the enzyne causes the fruit to ripen quickly. Add this to the aforementioned bacteria and you have gotten fruit."
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dr8stb | when you eat something and have diarrhea almost instantly, how does that work? the food can't go all the way through the small and large intestine that fast, right? | [deleted] | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/dr8stb/eli5_when_you_eat_something_and_have_diarrhea/ | {
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"It is called the gastrocholic reflex. Eating starts your lower colon, so whatever you ate 6-12 hours ago is exiting to make room for the new food.",
"It triggers the peristalsis that causes the contents already in your intestines to move through a little faster causing less water to be absorbed as stuff passes through the large intestines. So, when it emerges, your stool is more liquidy (diarrhea).",
"It's likely that whatever you eat before this happens is triggering this reaction. For me and my IBS it's pork, mayonnaise, and strong emotions. So sometimes it's not the food at all.",
"If your body detects that you've eaten something bad, your gut is triggered to try to get it out. In a worst-case scenario, you vomit. In other cases, the material in your large intestine is evacuated to make room for the bad stuff to move through later. If the irritation persists, it eventually does so in a rapid manner, and it is also evacuated. Otherwise, the process settles down and the \"bad\" food moves through your intestines, perhaps a little faster than it would have otherwise.",
"Your body can move things along a lot more quickly if it feels the need to get rid of something you ingested. When we eat normal foods, it takes hours for digestion to occur because that’s the amount of time we need to properly break down the food and absorb its nutrients and energy. But if we eat something our bodies don’t like, it can force the food down pretty quickly."
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5mklkd | why does hot chocolate have a drinkability window of about 20 seconds; whereas, it seems like coffee stays the perfect temperature for much much longer? | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/5mklkd/eli5_why_does_hot_chocolate_have_a_drinkability/ | {
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"Are you taking into account the environment? The temperature of hot water will drop much quicker when the air is cold/dry than it will when the air is warm/humid. If you only drink hot chocolate when it's cold out, but drink coffee at other times you may be introducing bias into your results."
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2dv110 | is the unit of selection the genotype or phenotype? | Does genotype determine phenotype, or vice versa? Is this the same question?
I've just started reading Gould, and my world is turning inside out. | explainlikeimfive | http://www.reddit.com/r/explainlikeimfive/comments/2dv110/eli5_is_the_unit_of_selection_the_genotype_or/ | {
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25didm | why does the strength of my wifi signal change so much when i move my laptop only inches? | I have been leaching wifi for many years in different locations, with different distances to the router and different model laptops. It seems that when the signal drops out, all I need to do is move the computer a few inches (not necessarily closer to the router) and the signal increases. Why do a few inches make such a difference when I'm 50 feet from the router? Thanks! | explainlikeimfive | http://www.reddit.com/r/explainlikeimfive/comments/25didm/eli5_why_does_the_strength_of_my_wifi_signal/ | {
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"It has to do with wave lengths that the router is using. Kind of like when you're listening to a radio station at a stoplight and rolling forward a little will make it either clearer or more staticy ",
"you are holding the laptop wrong",
"_URL_0_\nImagine this but with a house instead of an oven.\n\n\n",
"imagine the wifi router was a light bulb. between you and the lightbulb are a bunch of glass partitions, the light can go through them well enough, amongst them are some opaque things: furnature, plants, concrete columns, etc. you are sitting within line of sight of that lightbulb, but right next to you is a shadow cast by a column, in the penumbra you have enough light that you can tell what's up, but in the umbra you have next to nothing.\n\nthat's basically what's going on with the router, except things which are opaque to us, like walls and furniture, and plants. are transparent to it or translucent (concrete for instance is semi-transluscent, the wifi signal will go through but it will be weakened, like going through frosted glass) when something which is opaque to it, such as metal, sits between you and it, it casts a shadow where the light can be darker. (since wifi is just light on a frequency we cannot see)",
"Wi-Fi signals travel kind of like sounds do. Sometimes, you can hear something better just by moving your head slightly. This could be because sound is reflecting off a wall, or your ear is more directly in-line with the source. Same idea with wireless: signals bounce, refract, and do all sorts of other stuff. I've read about point-to-point Wi-Fi links that literally bounce off a skyscraper to get around an obstacle.\n\nAlso, the actual signal gained from a small repositioning probably isn't as pronounced as it would seem. Sometimes a slight improvement in signal is all that's necessary to get your signal to the \"good enough\" level, where your Internet works.\n\nFinally, there's also the possibility that moving your laptop actually didn't make any difference, and that something else changed in the short time it took to move it. For example, microwave ovens interfere with certain Wi-Fi signals, which can cause temporary disconnects.",
"In physics experiment land—an infinite empty void—the position of your laptop wouldn't matter much. With the access point's straight antenna straight up and down, even in height with your laptop, you'd see a very smooth change as you moved away from the antenna (or changed your angle to the plane of the antenna).\n\nNow, remember that radio is made of electromagnetic radiation, just like light. That means it can work like a wave (it can also work like particles; it's \"really\" not either, but for this, it's the wave behavior that's important).\n\nThe wavelength of wi-fi radio is about 12.5cm. Go to physics experiment land and put a magical perfect radio wave reflector 12.5cm away from your laptop on the opposite side from the router. Your laptop will suddenly see twice the average signal strength, as the radiation is reflected and the amplitudes match up perfectly: peak to peak, trough to trough. Now move the reflector 6.25cm closer (or further, whichever). Now, it's peak to trough, trough to peak. In physics experiment land, you suddenly have ZERO signal.\n\nBut you're in a real world. The air is basically transparent to wi-fi signals; actually, so is most stuff except water and metal. But there's metal and water all over everywhere in a house; appliance housings, pipes and wiring, cars outside, and people. Don't forget that your entire laptop is also full of electricity and metal.\n\nNow, it isn't just that these absorb the wi-fi radiation (though that happens too). In physics experiment land, there's exactly one path straight from the access point to your laptop. In the real world land, there's this crowded 3D landscape of all of these things can absorb and re-radiate, or partially absorb or deflect radio waves. There are potentially dozens of general sets of paths that a radio photon could take to get to your laptop. And some of those paths end up being 6.25cm longer than other paths, so they cancel; or 12.5cm longer, so they add. You end up with a shifting landscape of nodes where signal strength is reduced or increased.\n\nAnd that's why. I hope this wasn't too long or unfriendly an explanation. (I also hope I didn't get anything wrong, I sold my wireless networking concepts text book.)\n\nEdit: I now realize that several other comments cover basically the same idea. Well, maybe this longer less friendly version will be useful for somebody.",
"ELY5: Because even moving around by only a few inches allows the radio receiver in the laptop to pick up \"stronger\" and \"weaker\" portions of the quickly and rapidly changing radio signals from the transmitter. The signal is changing / modulating quickly to produce the desired bandwidth of Wi-Fi. This effect is amplified the further away you get from the router.\n\nRadio energy pockets.\n\nRadio energy is more concentrated (dense) in some areas and less concentrated (or dense) in others, sometimes these areas can be within inches even millimeters of each other. The inverse square law proves that the further you are from your source point of radiation, the more spread out the radio energy will be. This idea is best thought of as a balloon with a lattice of dots painted on it. As you blow up the balloon, the distance between the dots becomes increasingly larger. Because of this, it is known that radio energy can dissipate or be focused, and in the case of radio energy pockets, interferences like delays and reflections can focus radio energy into certain areas, and naturally, out of other areas. This happen all day long with Wi-Fi and your router. If you were to imagine Wi-Fi signals as an ether you could see in your home, you would see energy pouring out of your router, penetrating and bouncing off things at the same time. You would see a beautiful dance of radio energy bounce into and off of things as well as be absorbed and poorly reflected by other things, certain materials would even act as lenses, amplifying and distorting the radio signals as if they were light (because they are light!).\n\n_URL_0_\n\n\nYou most likely wouldn't have this problem happen in free space, away from other Wi-Fi signals / radio sources or objects to cause scatter/multipath/interference. If this issue occurred in a purely free space /radio free environment, I would be very confused.\n\nSource: I work with radio engineers and am in school for EE with a focus on radio.",
"There are two main reasons why a signal would drop out. The first, as alluded to by other posts here, is called fading. When a signal travels from the router to your laptop, it is radiated in all directions. (Well, not all, but nearly all with varying strengths.) When signals hit a surface, they reflect off of it. These reflections can cause the waveforms to interfere with each other, which is usually detrimental, since they are usually out of sync in time due to longer signal paths. This lowers the SINR (Signal to Noise and Interference ratio: S/(N+I)), leading to poorer performance.\n\nThe second is due to the antenna beam patterns, which describe how strong the signals are when radiated in various directions. Antennas radiate differently in different directions, and it's impossible to construct an antenna that radiates equally in all directions. This causes different signal strengths at both the receiver and transmitter for different orientations of the antenna.",
"ever heard static on the radio when stopped at a red light, but if you move your car just 2 or 3 feet forward it goes away? it's like that. noise and interference signal reflections bouncing off nearby objects just the right way to cause trouble... move a little and it's all better.",
"If you would compare the WiFi transmitters of your laptop and router with light bulbs, the radio waves could be seen as light beams (beams that shine trough walls). For the best result you want the light bulbs to shine at each other so they can see each others light beams. Metal objects can block signal, but it can also reflect it, see it as if it is a mirror. Some devices generate radio waves that interfere with WiFi signals, these signals can be seen as light waves that cannot be distinguished from the router or laptop.\nIn some places, a straight beam from the router to the laptop is not blocked and some other beams are reflected so that you can see each other very well. In other places, the beams are much more blocked, and less beams are reflected to the laptop and there might be some more interfering beams at that spot. Those places can just be inches away, especially if you're about 50 feet away. The more you are away, the more chance that straight beams are blocked and less reflected to you (not true in open field of course), more distance also means that signal is weaker.\n\nThe antenna for your WiFi adapter in your laptop is most likely built somewhere in your screen, so if you want to move some things that might block signal, you should keep that in mind.\n\nIf you have a USB WiFi adapter, a USB extender cable (not longer than about 6 feet) and an empty can (Pringles can is suitable too), you can make a [cantenna](_URL_0_), just make a hole thats big enough for the USB socket. With a cantenna you can focus your beam to your router, I've done it in the past and it works very well.",
"This probably isn't the main cause of your problem, but I highly recommend using a wifi scanner (on your laptop, phone, etc..) to see what channels other wifi networks in your area are using. When I scanned my apartment's building (just sitting on the couch), I found that 90% of the networks were all on the same channel range (+/- 1). Switched my router to the channel nobody was using and got better performance on multiple devices.\n\nEdit: Could someone point out to me why I'm getting downvoted? This could help OP's signal stability, even if it doesn't entirely fix the problem.\n\nEdit 2: Ok, further review of reddiquette answered my question. Carry on, fellow redditors."
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egdt03 | - pasta shape changes flavor. | Pretty much in the "interesting title"-how does pasta shape impact the flavor? The same ingredients cooked the same way taste vastly different because of the shape it's cooked in.
I get some shapes hold more or less sauce, but that's irrelevant to the flavor of the noodles. So, eli5? | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/egdt03/eli5_pasta_shape_changes_flavor/ | {
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"It doesn’t change the flavor, but it does change the taste and texture. So yes all pastas are NOT created equal.",
"basically it boils (no pun intended) down to gluten formation based on; how long you knead, how long you let rest and the different size of pasta extruder you use. but as the others said that gluten formation does very little for flavor and it has to do more with the different texture in your mouth. different levels of chewiness cause different levels of chewing, which in turn causes you to chew and break down the food more which causes different flavors to be released while chewing."
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3sif6a | why is "yes, i am" okay to say, but "yes, i'm" is not? | "No, I'm not" is okay, but "Yes, I'm" is not. | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/3sif6a/eli5_why_is_yes_i_am_okay_to_say_but_yes_im_is_not/ | {
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"If you say 'yes, I am', without anything following it, you are implicitly putting emphasis on the 'am'. You can't put emphasis and contract the word at the same time.",
"It's phonological, in English you put the emphasis on the last important word of your sentence, so you need the \"am\" to be in full form, while \"not\" is the emphasised word in \"No I'm not\"",
"\nUsually if you use \"Yes I'm...\" you follow it with a present participle (-ing) verb that actually serves as the primary verb in the sentence. \n\nBut it gets a bit confusing with your example. Adding the 'not' at the end of \"No, I'm not.\" is what makes it work. So you can't equate those two examples. Saying \"No, I'm.\" is incorrect. However, you could probably say \"Yes, I'm not.\" in some circumstances. It would sound weird but works grammatically because 'not' is serving as an adjective. Any adjective could fit after \"I'm\". \n\nSo I suppose either following it with a present participle, or an adjective will make it work. As for why? Who knows, English doesn't make a lot of sense when you think about it. "
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6uwhnp | how are companies like verizon and sprint able to use opposing companies names in commercials with out a lawsuit? | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/6uwhnp/eli5_how_are_companies_like_verizon_and_sprint/ | {
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"The law permits use of a competitor's name with certain limits. \n\nAnything that is said has to be truthful and *not misleading* Which means when a company makes a decision they don't ask themselves \"is this misleading\" but rather \"could anyone make the argument that this is misleading\" and it's not easy to have a solid no to that sometimes.\n\nThe law also allows using data from consumer studies or surveys as long as its represented truthfully.\n\nThis doesn't apply to Verizon/Sprint but if your product is intended to be compatible with another product or vice versa, then the other product can be mentioned in that context. ",
"There is no problem if it is not untruthful, misleading, or confusing to the public. In order to successfully sue for trademark infringement, you have to show that the unauthorized use is likely to confuse or deceive the public."
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aaglpf | it must’ve cost a ridiculous amount for google to map 90% of all roads on the planet for googleearth... what return does the company get for this massive project? | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/aaglpf/eli5_it_mustve_cost_a_ridiculous_amount_for/ | {
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"Google spends a certain amount on infrastructure building the maps. Then the user agrees to terms that say Google can track your movements while using maps. Then they can track drivers, suggest advertisers that pay google that are are along the route. and even deeper meta data about habits of commuters...",
"Google collects an incredible amount of data about it's users that they can then sell to other companies or advertisers. Google maps helps them figure out where people are trying to go and it functions like Yelp to profile locations. Google makes money off of information instead of traditional goods or services [Google's privacy policy](_URL_0_)",
"A lot of businesses purchase Google's map API and interface for their company sites. Redfin, Yelp, CBRE, Hilton, Marriott, and a ton of other sites use Google's API.",
"It's one of those services everyone wants, if you own it you can control it, and more importantly sell stuff in it.\n\nBy running google maps they get to sell business advertising in maps, and make it apply to a range of apps, they have also bought Waze, so on Both google maps and waze they get to insert adds into your maps. Waze for example highlights all the 7-11 locations, because obviously they paid for that.\n\nBut I think more importantly reason is google has always been a search company, trying to return search results to real places requires maps, you just can't tell someone about the nearby restaurants without maps. Trying to do it when you don't own the maps bogs you down in licensing, I am sure it's cheaper today to pay the 7,000+ people every year than it is to pay licensing fees to some other company.",
"One of their aims is to dominate, or at least take a healthy piece out of the autonomous vehicle market. Think about it, it has the potential to be Ford + Toyota + VW (etc) + Uber + FedEx + DHL (etc). Driving and recording every road, and getting captcha users to identify road signs etc, and android users to feedback traffic movement data, etc is all gently feeding data into their databases for machine learning",
"** > ELI5: It must’ve cost a ridiculous amount for Google to map 90% of all roads**\n\nTrue, but there are huge payoffs:\n\n1) People search for things on the internet, but **some of those things are places.** If places aren't \"in Google\", then people will find some other way to search (i.e. start Yelp or Bing or whatever). That is why Maps also collects data about hours, handicap parking, kid-friendly, etc. Google wants to answer **all** your questions, so you never start your search elsewhere.\n\n2) In the past, Google paid millions of dollars per year for map data (and frankly, those maps were not very good). So some of the **mapping cost is offset by NOT paying others** for the data. Imagine Google trying to negotiate a license to use Map data on a Billion Android devices being sold every quarter.\n\nSide note: because Google automated map collection to a degree that nobody else had ever done, their maps were cheaper to build than previous maps. \n\n3) Just like the old map providers, [Google **charges**](_URL_0_) **3rd parties** to use map data. (For example, if you want to build \"Yelp\", you will need someone to display the map, calculate the routes, etc. Google will do this for free ONLY on a small scale. If you get big, Google wants to be paid, or your app will simply stop working. You could use OpenStreetMap, but the data isn't as high quality everywhere.)\n\n4) Having map data **positions Google for self-driving cars** in the future. It's really hard to \"buy\" good maps (see problems of Apple Maps), so some car makers will end up paying Google in the future. Google cars will have an advantage because they can use the data for free.\n\n5) It also positions Google for other things in the future, such as their AI which calls to book appointments, etc. (You need to know which places are close, you need to know their hours, etc)"
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2hd38s | what's the big deal about sex with virgins that islamic extremists are promised this in heaven?? | Genuinely curious, because I would imagine sex with a virgin especially the first time is not that great in terms of mechanics and inexperience... this always bugged me. And why 72?? | explainlikeimfive | http://www.reddit.com/r/explainlikeimfive/comments/2hd38s/eli5_whats_the_big_deal_about_sex_with_virgins/ | {
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"The truth of the matter is most young jihadists are virgins themselves and have no concept of sexual intimacy. You don't see many old men martyring themselves...",
"Historically, it was important to men that any children their wife (or wives) bore were in fact theirs, and until recently, there was no direct way to test. \n\nSo instead they would control their wives, and this starts with ensuring they only married virgins. Women who were not virgins (widows, unwed mothers, rape victims) were considered inferior, and only men of lower prestige would marry them. ",
"It is a question of power and control. Virgins are younger, more malleable, easier to control, and have proven themselves trustworthy by staying virgin. Sex in Islam is very controlled so it makes for sexually frustrated Jihadists. Promise of control over virgins seems a worthy prize.",
"Based on what little research I've done, that's not true at all and almost zero muslims believe that. There's a bunch of muslim doctrine that they say straight up may have been corrupted and therefore no muslim has to follow them. So anyone googling muslim ideology can find that and assume they all believe that. Just like you could google christianity and find all kinds of crap almost no one believes.",
"sooooo, do the women get 72 virgin men?",
"In all honesty, why would woman remain a virgin, and 72 of them...would probably look like them:\n\n_URL_0_",
"Does it implicitly state that they are even women? I like to imagine Mohammed Atta showing up to 72 pc master race subredditers. "
]
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"http://n2.hk/u/attachments/day_140922/20140922_a2a90e41c6e21cead624numlpBXEfFS8.jpg"
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3mayyp | not sure how to ask this, but how is it possible to get these shots in movies (description) | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/3mayyp/eli5_not_sure_how_to_ask_this_but_how_is_it/ | {
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"Cameras positioned in a circle all recorded at the same time and played stitched together later.\n\n_URL_0_",
"Basically its a lot of cameras around the object of interest which shoot pictures shortly after each other or, depending on the wanted shot, all at the same time (if the object should not move at all). The technique is called Bullet time and is very well known from the Matrix movies.\n\n[Here's](_URL_0_) a picture of a bullet time shot."
]
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"https://www.youtube.com/watch?v=bKEcElcTUMk"
],
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"http://petapixel.com/assets/uploads/2012/12/bulletrig1.jpg"
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14ju76 | i recently heard that companies like google pay on their billions of dollars of revenue only a small percentage on income tax, please eli5 how this is conducted and why not every company uses such tactics | explainlikeimfive | http://www.reddit.com/r/explainlikeimfive/comments/14ju76/i_recently_heard_that_companies_like_google_pay/ | {
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"text": [
"Tax isn't on revenue, it's on profit. There are many steps to get from one to the later. Google has gigantic employee expenses for example.",
"First of all, tax is paid on corporate profits, not revenues. A company that has $1 billion in revenues but lost money in a given year would not owe any tax for that year.\n\nNext, even for a company that is profitable, companies with operations all over the world are often able to legally shift most of their profits to low-tax countries and their losses to high-tax countries.\n\nFinally, there are a lot of loopholes and special tax breaks that mostly large corporations can take advantage of. There are a lot of special favors in the tax code that congresspeople and senators put in for their own state or district's own businesses. Or companies play states and cities off against each other by offering to open a factory only if they can get a big tax break, or threatening to move to Mexico or China if they don't get a tax break.\n\nIf you have a small business, you can't do any of those things. No politicians are going to do you any favors, and you don't have international operations that you can use to reduce your taxes."
]
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2cur3i | what is spider silk made of and how do those little buggers have a seemingly endless supply of it? | explainlikeimfive | http://www.reddit.com/r/explainlikeimfive/comments/2cur3i/eli5_what_is_spider_silk_made_of_and_how_do_those/ | {
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"text": [
"They don't have an endless supply of it. They can only make so much, and their* webs are only so big.\n\nAlso, some spiders eat their* own webs when they are finished.",
"\"Scientists don't know exactly how spiders form silk, but they do have a basic idea of the spinning process. Spiders have special glands that secrete silk proteins (made up of chains of amino acids), which are dissolved in a water-based solution. The spider pushes the liquid solution through long ducts, leading to microscopic spigots on the spider's spinnerets. Spiders typically have two or three spinneret pairs, located at the rear of the abdomen.\""
]
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[],
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1hlgby | why did the majority of egypt vote for mohammed morsi if he was a part of such and extreme political party (muslim brotherhood)? | explainlikeimfive | http://www.reddit.com/r/explainlikeimfive/comments/1hlgby/eli5_why_did_the_majority_of_egypt_vote_for/ | {
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"text": [
" The opposing side split their vote, allowing him to ride to victory.",
"As someone else mentioned, the vote was indeed split. That said, it should also be mentioned that the Muslim Brotherhood had a tremendous amount of credibility among Egyptians due to their impeccable anti-regime record throughout the Mubarak years. For a long time, they were just about the only well organized opposition movement that existed."
]
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80c8ad | how do the bank/credit card company know someone is using your account/credit card, effectively freezing your card before you even get a chance to call up about a suspicious activity? | For example, someone is using your credit card information to make a purchase through a phone order. The credit card company immediately put a freeze on the credit account. How do they know that it's not the original owner using the card and that a fraud has been committed? | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/80c8ad/eli5_how_do_the_bankcredit_card_company_know/ | {
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"They (or more specifically their processing systems) look for oddities in \"your\" spending habits. Unusual locations. Unusual purchases. Unusual amounts. Known fronts for money laundering. Basically, anything that matches their database of known fraud patterns\n\nPhone and internet orders make it a bit more difficult, but they have enough experience watching for fraudulent purchases they can catch a lot of them in the act",
"because it's the first time you've made a phone order of over £200 to a company based in Bulgaria and they would think that was unlike you.",
"They track your data just like facebook or google. So if something doesn't seem like you either by your spending habits, your spending amounts, your location, etc they know its suspicious. ",
"The other thing they look at is where your buying. It would be odd if I did my grocery shopping in one city this morning then bought something on the other side of the country. ",
"I had a travel alert with USAA last month for Thailand and Singapore. All was well until about 4 days into my trip. Two purchases totaling $900 were made in the Midwest of the US at a time where it was 4AM my time. USAA alerted me instantly, I woke up to the messages. They told me they 1. Used my travel alert to red flag a purchase in the US and 2. The time differences seemed suspicious for me making such a large purchase at 4AM local Thailand time. Card blocked, funds returned, all was well. \n\nThis is why I always suggest making travel alerts, even if it’s within your home country.",
"They look for unusual spending. For instance if there was a $300 charge for a supermarket that's 2 hours away from me, that looks pretty suspicious when I rarely spend more than $50 at a time at the supermarket.. not to mention why would I go to one that's 2 hours away.\n\nSometimes there are false positives though, and also services to let you notify them that you're going on a trip so they won't flag your charges that are suddenly coming from halfway around the world as fraudulent."
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d2fv7k | why does one of my eyelids droop when i'm tired? | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/d2fv7k/eli5_why_does_one_of_my_eyelids_droop_when_im/ | {
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"Is it whenever you're tired or just at the end of the day? Do other muscles in your face/body get tired? Not super likely, but dropping eyelids makes me think of something called myasthenia gravis. With this condition, muscles essentially run out of juice when you use them over and over and get tired, so lots of people have droopy eyelids, worse at the end of the day. Try putting an ice pack on it, and if the droopy goes away you might want to mention it to your doc.",
"I work with an ophthalmologist. Maybe ask your doctor about drawing bloodwork up to rule out ocular myasthenia gravis."
]
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1ishk2 | the rules of and differences between snooker and billard. | I've caught Snooker and Billard on cable before,it's very interesting but I have no idea what's going on,which ball you can't score and which you can.Can someone clear up for me? | explainlikeimfive | http://www.reddit.com/r/explainlikeimfive/comments/1ishk2/eli5the_rules_of_and_differences_between_snooker/ | {
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"Snooker is played on a table that's much bigger than you average pool table. The pockets are smaller and have round edges instead of sharp ones. The balls and queues are also smaller. This makes snooker a much more challenging game than standard billiards.\n\nThe basic rules are:\n\nThere is one queue ball (white) which the players take turn hitting. There are 15 red balls. You must only hit (and pocket) a red ball. If you do, you may continue onto pocketing a coloured ball. The coloured balls \"respawn\" when pocketed. The red ones don't. If you manage to pocket a coloured ball, you may now try to pocket a red one, and so forth.\n\nSo you combo as following: Red- > coloured - > red - > coloured\n\nA red ball is worth 1 point. The coloured balls are worth 2-7 points, with the yellow having the least value, and the black having the most. \n\nAfter all the red balls have been pocketed, you strike the coloured ones in succession, in ascending value, yellow to black.\n\nTherefore, the most attainable points is 147 in a single combo. Red - > Black - > Red - > Black (until all the red ones are pocketed) - > Then all the coloured ones.\n\n---\n\nStandard billiards = 8 ball. This is the game you'll find at most bars, homes, restaurants, etc.\n\nThere are 15 balls. 7 Whole, 7 striped, 1 Black (The 8th ball). There is one queue ball (white). In the beginning you may pocket any ball (except the 8th ball). If you pocket a striped one, that is now YOUR colour, and you may only try to pocket striped ones from then on. Player 2 automatically becomes \"whole coloured\".\n\nThe first player to pocket all the balls of his colour (striped / whole), and finally ending with pocketing the 8th ball, wins. \n\n"
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62a2yr | why does walmart only have a few registers open, yet they are number one on the fortune 500 list? | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/62a2yr/eli5why_does_walmart_only_have_a_few_registers/ | {
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"text": [
"You reversed a statement to make it a question...\n\nWalmart only schedules the minimum number of cashiers needed to keep customers from leaving the store without buying anything, and pays those cashiers the least amount they can without having the cashiers walk out. This business strategy has led to them being at the top of the Fortune 500.",
"Think about it this way - if walmart has less registers open, their operating costs are less, and thats why they are on the fortune 500. They know how to generate revenue"
]
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5rd2w9 | the constant e in logarithms. | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/5rd2w9/eli5_the_constant_e_in_logarithms/ | {
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"Let's imagine you have some bacteria that split once per hour. You start with 1 million bacteria, then an hour later you have 2 million, then an hour later it's 4 million, then 8 million, then 16 million, and so on. You write out a formula for how much bacteria there is after N hours, and you get 1,000,000 \\* 2^N (note that 2^0 is 1, so this formula is just fine).\n\nWhen you look at this population you might ask \"how fast is the population growing?\" Well, over the first hour it grew by 1 million bacteria so you might say that it's growing at 1 million bacteria per hour, but if you counted every 30 minutes you'd find that there's only about 1.4 million after 30 minutes but after a full hour there's 2 million, so maybe you say that the population is growing at about (400,000 bacteria) / (30 minutes) = 800,000 bacteria per hour for the first half hour, then 1,200,000 bacteria per hour for the second half hour.\n\nYou could keep on looking at the growth over a shorter and shorter period of time and you'd get a more and more accurate measurement of the bacterial growth per hour.\n\nWhat you'd notice is that the number of bacteria added to the population per hour is always a constant multiple of the population: when the population is 1 million the growth rate is 693,147/hr. When the population is 10 million it's 6,931,472/hr, and so on. There's always that constant ratio of .693147.... between the growth rate and the number of bacteria there are.\n\nNext we look at another population of bacteria that split a little faster. They *triple* their population each hour, so you start with 1 million bacteria, then an hour later you have 3 million, then 9 million, and so on. You come up with a formula for this population and it's 1,000,000 \\* 3^(N).\n\nAgain you look at how fast the population is growing and again you find that there's this constant ratio between the number of bacteria you add per hour (as measured over a very very short period of time) and the number of bacteria there are. This time, though, the ratio is different: it's 1.0986... \n\nAt this point you ask \"How fast does the bacteria have to grow to make that ratio be 1?\" We've seen that doubling in an hour is too low, while tripling in an hour is a bit too high. We could guess a few more numbers and home in on the answer: 2.71828...., or *e*. If we had a population of bacteria that had an equation of 1,000,000 \\* e^N then at any instant you're adding more bacteria at a rate exactly equal to the population (i.e. when you have 1,200,000 bacteria you're adding them at 1,200,000/hr).\n\nThis idea is the fundamental definition of what *e* is. In calculus we call this idea of \"rate of change, as measured over an incredibly short period of time\" a derivative, and the derivative of e^x is e^(x). The constant e is the only number for which that can be true; for any other number you wind up with those constants.\n\nYou asked about logarithms, but logarithms are just backwards exponentiation. They confuse people because they're written as a word, but they should be no more confusing than learning that subtraction undoes addition or that division undoes multiplication. If you see that 1 + 2 = 3 then you should be able to work out that 3 - 2 = 1. Similarly, if you see that 3 \\* 4 = 12 then you should be able to work out that 12 / 4 = 3. With logarithms it's the same but written more confusingly: if 3^4 = 81 then log*_3_*(81) = 4.\n\nWhen you deal with exponential growth you often deal a lot with e as the base, since it has that property I mentioned earlier of having a rate of change equal to itself. You also frequently have to deal with undoing the exponentiation if you want to find the exponent and just know the base and the answer, hence bringing in logarithms. These two things coincide often enough that it's efficient to just have shorthand for \"do the reverse of e^(a) = b\" so we write ln(b) = a. "
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5ftkiq | why didn't the american south's economy irreparably collapse after emancipation? | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/5ftkiq/eli5_why_didnt_the_american_souths_economy/ | {
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"The economy was indeed severely hurt. However, crops could still be grown, and labor was still available cheaply (freed slaves became sharecroppers, not exactly costly labor), and very basic mechanization increased (like the famous \"cotton gin\" for separating newly-picked cotton).",
"It did collapse after the civil war and many economists say that it is still suffering hardships from the losses had then and forced upon it during the reconstruction era. \n\nBut the total US economy grew fast enough and large enough that it mostly counteracted the collapse and just had the south lag behind the north rather than being in abject poverty. ",
"The South's economy did collapse irreparably after emancipation. Today Southern states are among the poorest in the Union and consistently receive more federal funds than they give. But there are reasons for this that go beyond Emancipation.\n\nFirstly, in the wake of the civil war, the Reconstruction era was an abysmal failure. Money intended to build better infrastructure wound up vanishing into the pockets of corrupt moneyed interests, and continued political violence against African Americans made it difficult to establish the kind of order, stability, and predictability necessary to draw investors. In many ways, the American South had a chance, but it was stolen by their own corrupt and racist leaders.\n\nMoving forward, the economy of the world was shifting. America's Northeast was already industrialized where the South had been an agricultural bed. It's believed that this is why the North was able to win the war. They had substantially better manufacturing and trade, and that gave them a stronger economy, wartime or otherwise. This dominance of manufacturing in the north continued as infrastructure continued to expand where there was already a demand, rather than in the unindustrialised farmlands of the South.\n\nLastly, the American West drew all of the speculative investment. After the civil war, small town communities were starting to press up in the west. Great cattle runs were bringing meat home from newly settled homesteads, railways were being built to the big cities of the west coast, and all of that was impossible competition for the South.\n\nThis has been a pretty consistent theme in the South for a long time. Many still blame emancipation for this fate, remembering the wealthy days before it. But it's important to remember that even without emancipation, the industrial revolution and the rise of cowboy beef would have presented a huge economic challenge to the South. It's likely that they would have wound up poor anyway. But losing a war is always bad for business, and racist violence after the war played a large part in making things much worse."
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9pjwiz | does near-sightedness give you super sight? | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/9pjwiz/eli5_does_nearsightedness_give_you_super_sight/ | {
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"Basically, you have your own macro lens. You can get much closer to an object, and thus project a larger image onto your retina, while still keeping focus.\n\nI have moderate myopia (+5.5 correction required) and it is a noticeable effect.\n\nI hesitate to call it a superpower, but it's a neat trick.\n\nI can only focus to about 5 inches though, perhaps affected by my age ; 1 inch is much more impressive."
]
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6f4mva | why is china (as in porcelain plates) called china? | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/6f4mva/eli5_why_is_china_as_in_porcelain_plates_called/ | {
"a_id": [
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"score": [
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"text": [
"Because porcelain goods used to overwhelmingly come from China. Most of the Porcelain goods you would have seen in early modern England (or earlier) would have come from China."
]
} | []
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[]
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|
||
ylacd | elia5 how to read a barometer like the one your grandparents probably had. | explainlikeimfive | http://www.reddit.com/r/explainlikeimfive/comments/ylacd/elia5_how_to_read_a_barometer_like_the_one_your/ | {
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"text": [
"Barometers measure just how hard the air, going all the way up to space, is pressing down on you at that moment. There's lots of different types of barometers, but they all show the same thing with various accuracy. \n\n* If the barometer is indicating high pressure, the weather will usually be good\n* If it is indicating low pressure, the weather is going to be bad\n* If the barometer is falling quickly this is a sign that there will be a storm coming"
]
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|
||
56c9ns | what causes this sting that you feel in your chest when you get frightened or realise you forgot something important? | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/56c9ns/eli5_what_causes_this_sting_that_you_feel_in_your/ | {
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"text": [
"In both cases, your brain triggers your sympathetic nervous system (fight or flight response).\n\nOne of the effects of such a response is an increased heart rate. The initial effect of this sudden acceleration is an increased blood pressure in your left ventricle, leading to this stinging sensation.\n\nJust as other cases of acceleration vs velocity, the acceleration is the much more noticeable sensation."
]
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| []
| [
[]
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|
||
6gdmct | if the purpose of life is to reproduce, why does biology allow us to live longer than needed? | [deleted] | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/6gdmct/eli5_if_the_purpose_of_life_is_to_reproduce_why/ | {
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"There is no evolutionary disadvantage to living longer in most cases, and being able to care for our young for extended period of time is often helpful. Besides that, humans are smart. We learned to fuck with chemistry such that we just live longer, whether nature likes it or not. \n\nAlthough I dispute your claim that reproduction is the 'purpose' of life. Life just reproduces. By definition. Purpose implies a giver of purpose which is not indicated.",
"In nature many animals don't die of old age. They get weaker as they age until they can no longer run away from predators and they are taken down. Old age is a luxury only available to very smart and resourceful animals, and human culture, it's laws, and society. \n\nTo some extent as an animal or person ages, they get really good at what they do and are much better at it than a younger, stronger animal of their species. But eventually no amount of cunning can make up for the physical deterioration that occurs from age and they either die from illness or predators. \n\nIf you think about evolution as making better animals to survive long enough to reproduce several times, then it got so good at it that even after they reproduce they are too hard to kill easily so they live longer. \n\nSome animals have built in death tied to their reproductive practices. It gives them an advantage in that they don't compete with themselves. When the old die to make way for the young they aren't having young and old compete for limited food and shelter. But the downside is the old can't teach the young. So it might work for animals with biological memory and instincts but in animals that mature slowly the bond between parent and child is stronger and it can take decades to pass on all of their knowledge to their offspring, such as with humans, apes, elephants and other animals. ",
"It's evolutionarily adaptive to be a supportive grandparent. Helping your grandchildren survive increases the likelihood that your genes will make it to the next generation. ",
"Well, for instance, my father is 65 and still working full time, making more money than he knows what to do with. He gives money to my brother and I, to help us provide for our children. His direct descendents are better off with him still kicking around. And that's not to mention the social and cultural benefit of having old people around.",
"First off, to address 2 immediate flaws in your question; you seem to imply (intentionally or not) an intelligence to biology that doesn't exist, and I would argue that procreation is not necessarily the only purpose of life. \n\nThat being said, let's assume that procreation is the sole purpose of life. Procreation doesn't begin and end with conception and birth. Most organisms rely on fellows from their own species for survival in some way (especially in infancy), either via simple protection and nourishment, or through teaching. By having the parents live beyond the birth of a child, not only do those parents often have the chance to conceive again, but they protect, nourish and train the infant so as to better improve that infant's chances of reaching an age of being able to procreate as well. \n\nIn addition, lets not forget that there is the matter of procreation at the individual level versus procreation at the species level. There are many species where organisms are born that are not intended to ever directly procreate, but they support the rest of the community to allow the species to continue. A prime example of this would be insect colonies, such as bees. And even in species where all individuals have the potential to mate, they still may serve the species in some capacity well beyond their ability to procreate has passed.\n\nIf your question was directed at humans, I would raise the point that when biology reigned over us completely, we were no different than any other species in that we lived so long as we were useful either individually or on the larger communal level. However, we have arrested control of our biology in many ways, and have used modern medicines and technologies to increase our life span significantly past what is needed for the simple survival of the species. That being said, one could argue that many of the elderly still offer important contributions to species procreation in the way of knowledge and wisdom despite the extreme age modern medicine has allowed."
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4ppfv0 | (programming) how does software limit its bandwidth usage? | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/4ppfv0/eli5_programming_how_does_software_limit_its/ | {
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"text": [
"The exact implementation will depend on what level you're talking about. But the basic process is that you only send a certain amount of data within a given time frame."
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cnozht | why do road maintenance workers dump dirt all over the roads they've recently completed work on? | I live in a larger town in Canada currently undergoing a lot of road construction. I've noticed that upon completion of a project, road crews dump dirt all over the road for some reason. Not in one heap in one spot, but evenly throughout the entirety of the newly constructed road. Almost as if they were glazing the new road with dirt. I've noticed this at least 6 times now and I cannot for the life of me hazard any guesses as to why this happens. It seems really unusual to me, and the more I think about it the more I'm perplexed. Could someone please ELI5? | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/cnozht/eli5_why_do_road_maintenance_workers_dump_dirt/ | {
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"text": [
"It makes the hot asphalt less sticky/tacky so that cars driving across the freshly laid road don't then track hot asphalt onto other roads, parkign lots, residential driveways, etc.",
"2 reasons. \n\nDirt is REALLY good at cooling. \n\n\nAsphalt comes out as a boiling hot liquid tar. \n\nAlso, Asphalt takes time to fully cool and dry, so the dirt acts as a layer of traction to drive on without getting hot tar in your treads. \n\nThen you can just wash away the dirt later on for that cool flat blacktop look of a freshly paved road"
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efbtzx | how do children of mixed races have a blended skin color? why don’t they inherit the skin tone of one parent like most other genetic traits? | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/efbtzx/eli5_how_do_children_of_mixed_races_have_a/ | {
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"Mixed kid with a geneticist mom here! Skin color is considered a polygenic trait, meaning that it’s dictated by several genes. You get dark genes from one parent and light genes from the other. Usually, you end up somewhere in between.",
"The gene to encode skin color isn't just the basic dominant recessive gene you learned in freshman bio. It is eight or so genes long with poor white being aaaaaaaa and pure black being AAAAAAAA. If these two pure people had a child they would be mixed as AaAaAaAa and that while result in 50/50 representation of the two genes. The genes aren't fully dominant or recessive which allows this to happen.",
"Because skin color is controlled by 3 different gene pairs, not one, as many common traits are. Each gene has two alleles, as normal. Each be be either for dark skin or white skin and they are co-dominant, so the number of dark skin alles is what determines how dark your skin is. If all six of them are for dark skin, they you have extremely dark skin and if all 6 are light you will have pale light skin and if 3 are dark and 3 are light, it will be in the middle. \n\n\nso if you have a light skinned person with 6 light alleles who has kids with a dark skinned person with 6 dark alleles, their kids will all have 3 dark and 3 light alleles and thus be halfway between. \n\n\nIf on the other hand you have say two missed racial parently with 3 and 3 or maybe 4 and 2, then you can get some crazier combinations out of it in rare occasion, which is how you get fraternal twins where one looks white and the other looks black, even though both have exactly the same ancestry and are mixed-race.",
"“most other genetic traits” - I assume you’re referring to eye colour, which indeed tends to follow one parent directly. \n\nHowever, most traits are in fact a lot, lit, lot more complicated than those 4/16 bennet squares they teach in senior high school or 1st year tertiary science. \n\nGenetics tend to be a lot more soup-y... hard to pick out a single element...",
"Most genetic traits are controlled by a large number of genes. Skin color has 16 I think.\n\nThe pea plants mendel studied are the abnormalities for only having 1 gene. If he'd been looking at nearly any other plant or any other traits it would have been to complicated to see easily."
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7d886z | why are songs with music videos way more popular than same songs without videos? | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/7d886z/eli5why_are_songs_with_music_videos_way_more/ | {
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"Visual stimulation to accompany the audio. Typically artists have a channel and it gets more traffic than someone who uploaded just an audio clip. The bigger channels are also usually higher quality sound."
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2qw7sv | why is one of my nostrils 90% blocked, even when i don't have a cold? | explainlikeimfive | http://www.reddit.com/r/explainlikeimfive/comments/2qw7sv/eli5_why_is_one_of_my_nostrils_90_blocked_even/ | {
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"Could be any number of things, but more likely to either be a polyp (benign growth) or septal deviation (the cartilate dividing your nostrils bending).\nBoth of which would reduce potential air flow, giving you the blocked feeling.\nBlockages also make it more likely for you to develop sinus infections/make them slower to clear",
"If I'm understanding the question correctly... \n \n(read this in a previous question, paraphrasing) This is normal. Your body controls the sinus pathways so that one is always getting temporary relief while the other is in primary use.",
"Your body blocks off one nostril to some degree throughout most of the day. There are a few theories as to why this happens. The one I've heard the most, and that makes the most sense is so that one nostril can excel at breathing while the other slows down the air so that you can smell more effectively."
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2osqnj | the sat | I'm a junior in high school and almost all my friends have already taken the SAT or plan to in one month. I'm too afraid of looking stupid (we're all AP/Honors kids) to ask wtf the SAT really is. I get that it's a test and that it's important for college or something, but I know nothing else.
Can someone explain basically everything about the SAT? Like what it is, it's significance, how/where/when to take it, etc. | explainlikeimfive | http://www.reddit.com/r/explainlikeimfive/comments/2osqnj/eli5_the_sat/ | {
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"So, the SAT is a standardized test (so, lots of bubbles to fill in and multiple choice) used in lots of the US and some parts of Canada to assess your readiness to go to college. As such, it is an important part of your college application process. There are 3 parts: Math, Critical Reading, and Writing. Math is doing math problems of various sorts (algebra, geometry, etc.) and selecting the answer from 4 options. Critical Reading is reading a passage, then answering questions about it from 4 options. Writing is a bunch of multiple choice (to identify errors and how to improve certain sentences) and a short essay (to demonstrate writing ability).\n\nEach section is 800 points, for a total possible score of 2400. It costs like $55 to take, and there are several test dates throughout the year. Check out College Board's website, as they are the ones who do the test. You may also look at the ACT, which is a similar assessment test used by other US schools.",
"It's a test that's offered all over the country. It's run by the College Board, the same company that runs the AP exams. Because the same exam is given all over the country, it provides a better benchmark than GPA for comparing between students (someone could have a high GPA because their teachers were all pushovers, even if they weren't terribly good at the material).\n\nThe exam scores are used for college admissions. Colleges will want to see either your SAT score or an ACT score (the ACT being a competing test). Most schools will accept either one, although some schools have a preference. They're not *the* deciding factor about whether you get in or not, but they are a factor.\n\nYou can sign up to take the exam and find out more about it on the College Board's website- _URL_0_ They also have a practice exam up there if you want to see what it's like."
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6b5zmn | why is it that when when a human is ill it seems as though the body is inflicting most of the acute symptoms on us? | For instance: You get a UTI, your body continually goes from hot to cold sweats and all your muscles ache. Same with the flu. Does this serve a purpose in protecting us from further damage? | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/6b5zmn/eli5_why_is_it_that_when_when_a_human_is_ill_it/ | {
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"Fever is a way that your body is trying to kill off the microorganism, through creating a \"wrong temperature\" environment.\n\nSome of the other symptoms are related to inflammation, another of the body's primitive immune responses trying to make a bad environment for the invader.",
"Symptoms are typically side effects of the body fighting off the infection. For example, raising your core temperature makes it harder for microorganisms to grow. The side effect, however, is extreme discomfort as our regular body temperature is the one in which our cells function best. Another issue is that our immune system is very zealous when it comes to fighting off invaders. So zealous that there tends to be quite a bit of collateral damage that kills off our own cells and can lead to inflammation and discomfort. This is still better than the alternative, which is to allow the invader to grow unchecked, which will eventually compromise our entire body and kill us."
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6xtxat | if threatening people is illegal, why were protesters allowed to carry nazi flags and call for the death of groups of people like black people / jews? | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/6xtxat/eli5if_threatening_people_is_illegal_why_were/ | {
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"Because the First Amendment distinguishes between advocacy of violence and incitement of imminent violence.\n\nIt is not illegal to advocate and support violent acts.\n\nIt is illegal to try to persuade people to commit violent acts right now.\n\nSo carrying torches and calling for genocide = totally legal.\n\nCarrying torches and calling for people to start committing genocide right now, let's go, we need to do this now = totally illegal. "
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5a6qjy | how are random product/reward codes generated? | Many digital items (movies, promotions and *especially* video games) often have a code in a specific format (ex. Xbox codes are XXXXX-XXXXX-XXXXX-XXXXX-XXXXX) for a product, an item companion to it, etc. How is it actually produced, and how can so many be made, let alone for a single item, and not run out of possible combinations for characters? | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/5a6qjy/eli5_how_are_random_productreward_codes_generated/ | {
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"Lets assume for a moment the key is comprised of just uppercase letters. This allows for 26 options for each character of the key, giving a total of 26^25 possible combinations. 26^25 is about 2.3\\*10^(35) total, or about 3.2\\*10^(25) (that's 32,000,000,000,000,000,000,000,000) possible combinations *for every living person on Earth*. So no, we probably won't run out of codes soon.\n\nSometimes the keys follow a certain pattern, that allow the program to validate them (so that not every 25 character combination is valid). For example, the last 5 characters in the key might be created using a function of the first 20, so it's easy to check whether the key is valid by applying this function and comparing the result. This reduces the possible number of combinations, but there's still a lot of them (\"just\" 26^(20) instead of 26^(25)).\n\nThe code is produced by a pseudorandom number generator. As to how these work, well that's another question altogether, [which has been asked here many times](_URL_0_).\n"
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1hq7sf | why do people actually think snowden is a traitor? | edit: I should say *some* people | explainlikeimfive | http://www.reddit.com/r/explainlikeimfive/comments/1hq7sf/eli5_why_do_people_actually_think_snowden_is_a/ | {
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"whether you agree with what he did or not he violated his freely taken oath required to attain a top secret security clearance, he gave away classified information that has not his, and then he left the country to avoid facing his actions. Those are the facts not opinion, but sounds like a traitor to me. \n",
"Mainly just due to the fact part of the contract, that he signed and sealed (with a kiss, perhaps?), was to never relay the information that he may come across in work, regardless of what that information may be.\n\nWhether that is morally right or wrong, doesn't matter, he signed it, he accepted it. Yet he went against that and told everyone everything he knew.\n\nHe then fled, mainly because he'd know the US would kick his ass for doing so (it's a serious crime after all).\n\nIn some peoples eyes, yes that would be a traitor."
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746s7s | how complex are animal 'languages'? | So, as pretty complex animals, humans have pretty complex languages and can discuss all sorts of things. Most animals are much simpler, but do we know how simple their communication is?
Sure, some animals are fairly quiet and only make sounds when in distress etc, but many animals are much more vocal (like common birds). Are they actually talking about things or just trying to be heard?
And as for animals that work in packs or groups, do they have a proper line of communication or just act on instinct? | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/746s7s/eli5_how_complex_are_animal_languages/ | {
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"TL;DR: VARIES GREATLY by species and native intelligence levels.\n\nThere's a tremendous variety in the levels of intelligence and, alternately, cleverness, in various animals. This often translates directly to the complexity of their language. Same goes for pack behaviours: some are learned (e.g. lions hunting), some are purely instinctual (e.g. division of labour in termite nests). \n\nAnd it's important to realize that language is not limited to vocal elements - body languages, smells/pheromones (particularly during mating seasons) and dances often contribute to communication between animals. \n\nIn very rough and debatable order, and there are all sorts of other examples:\n\nMost insects don't really communicate beyond the instinctual level. There's no actual thought behind it, it's just automatic. One of the more sophisticated communications is bees \"dancing\" the direction and distance of fields of flowers when they arrive at their hive. \n\nReptiles and amphibians have vocalizations that mostly announce their presence, although frogs can get into some pretty loud \"hey this is my territory\" duels during summer nights at the pond.\n\nFish are mostly instinct-type communicators. Some use visual signals and water pressure changes in schools, helping them to coordinate movement. A few vocalize. Squid and octopi can send visual signals to each other through changing the colour of their skin; some are thought to be as smart as dogs.\n\nBirds are near the top of the list, with highly intelligent gray parrots being taught huge vocabularies of human words to the point where some can make their own sentences. As superb mimics, they have the advantage of being able to actually shape their communications to exactly match our own. Many other species have more limited vocabularies that they use among themselves, with word count ranging from a few basic calls for nighthawks to a high number of different coordinating communications for crows. \n\nThen there's mammals, and most use just basic words like wolf howls or happy barks to communicate. Some are even dedicated to crossing species; cats meow at humans but not so much when we're not around. Cetaceans like dolphins and orcas and whales have very complex songs though, and a lot of fairly complex communication goes on between them. There's a lot of non-verbal communication that happens in chimp tribes.",
"Animal communication is a very complicated and little-understood subject, but from available evidence it would appear that no form of animal communication comes anywhere near the complexity of human language.\n\nVery complex birdsong is mostly just showing off -- \"Listen to all the different sounds I can make!\" The typical things a bird might \"say\" are: \"I'm horny,\" \"This is my patch and I will defend it,\" \"I'm here,\" \"It's time to flock together and migrate, who's with us?\" and \"Danger!\"\n\nWolves certainly do use communication to coordinate their actions. It's not just vocal, but body language as well. They even appear to vote: if their leader wants to, say, go hunting, they might gather and then cast their votes by sneezing.\n\nThat's a very sophisticated form of animal communication, but human language still knocks it clean out of the water. We can talk about abstract things, we can talk about things happening in different places or at different times, we can even talk about things that haven't happened yet or may never happen at all. By contrast, animals appear only to be able to communicate things that are happening *here* and *now*.\n\nAnother feature of human language is that it is \"open-ended\" and \"productive\". This means that although we only have a finite number of symbols (sounds and gestures that make up the language), we can talk about an infinite number of things, including things nobody has ever talked about before. Animals by contrast can only talk about a finite number of things: they can say, \"I am hungry,\" but they can't say, \"A rose by any other name would smell as sweet.\"\n\nThere are claims -- and they are very controversial claims -- that primates can be taught to communicate with humans in ways that mimic human language. The most famous is Koko the gorilla, who has been taught American Sign Language. The researchers working with her claim that she can not only talk about things that happened in the past, she can even make up her own phrases (for example, signing \"dirty bad toilet\" as an insult). But some linguists are skeptical of these claims, saying that the signs Koko produces are so vague and poorly executed that you can't tell what, if anything, they mean.",
"It seems to be very primitive, but some birds do seem to have different words for different types of threats. So, instead of a general \"predator\" they have \"falcon\" and \"panther\" cries. "
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29vi1m | why haven't any recent composers of classical music gained notoriety? | I've recently dipped my toes into classical music, and I have yet to really come across anything that isn't just a composer playing older composers music. Why is that? It seems like the only really recent "Classical" music that I've come across has been music from movie soundtracks.
Edit: That was quick. Thanks guys! | explainlikeimfive | http://www.reddit.com/r/explainlikeimfive/comments/29vi1m/eli5_why_havent_any_recent_composers_of_classical/ | {
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"There are *tons* of modern composers.\n\nIf you are just dabbling, keep looking. Remember though that the popular notion of 'classical' music was very well developed and explored some time ago... So when you hear Beethoven and Bach and Mozart you are hearing music of that time. Later you may see Bartok and Schonberg and Mahler and..there are hundreds or thousands of composers that span that time.\n\nNewer? Philip Glass. Steve Reich.. There are many. Again, you are not going to hear an Allegro - andante - scherzo - allegro arrangement because... Well because it's been done so completely and so well.\n\nYes, they get radio time, but not on 'rock 100 fm' or 'serius hits 1' of course.\n\nTL/DR - there is lots of it out there. Try looking for a classical music sub or go to _URL_0_ to dig into it.\n\nBe careful though, it's a rabbit hole!\n\nStart with what interests you, it will lead you to who knows what area of 'classical' music. The important part is to find something you like and start exploring there.",
"Really, becoming famous for writing musical or movie scores isn't so different from becoming famous for writing opera scores, so the notoriety of people like Hans Zimmer, Stephen Sondheim, John Wiliams, etc. isn't so different from the notoriety of Mozart and Wagner.\n\nAlso, keep in mind that only a tiny, tiny percentage of composers from any time become famous, and even fewer are recognized in their own time. It's not too unusual for so few composers to be a big name.\n\nThere are some composers who, like Stravinsky or Beethoven, are pushing the envelope with music and aren't appreciated (yet). The people who compose pieces that ask \"What is music?\" and break the established rules may not be truely appreciated until you and I are long gone. Check out the reaction to [John Cage's *4'33''*](_URL_0_). John Cage's music is groundbreaking, but it may not be fully appreciated for a long time.",
"Also the form as you are thinking of has been done. Wereas there is an endless need in the world for Rhianna's booty shake there are not many calls for a new Beethoven 9th. \n\nThere are modern classical composers but style would be called avante gard or experimental. The only one i think you might have heard of is Phillip Glass. Try downloading and listening to his Ahkenaten. Its not Bach. You may not find it listenable. Its different",
"As others have said, they're out there - just not as common. \n\nThat said, consider that 'classical' music was essentially the pop music of its day. You can follow mainstream western music as a relatively straightforward path from very VERY old music to the early 20th century. When African rhythms were brought into music, jazz and blues formed - and that begat rock music, country, and everything else eventually. Music from every culture - modern and primitive - has come together to open the 21st century.\n\nWe've got more variety of music now than at any point in human history. We also have a greater *quantity* of new music than at any point in human history. How do you find stuff that's being written now in the less popular genres? You have to look harder for it, simple as that.\n\nAnd there is some amazing new classical music out there.\n",
"One thing missing so far is the filter of time. There were thousands of other classical composers that we no longer remember. It's like how almost all of the books the average person knows from before ~1900 are classics. As a society we lose anything that isn't awe inspiring.\n\nI would suggest looking at some composers for wind band or chamber ensembles. A lot of great composers work there, like Ticheli, Whitacre, and Del Borgo. Plus, it will mostly be modern composers, since it is a newer form. ",
"What does \"Classical\" mean here? It means it stood the test of time. It's not exactly a genre like many people assume. \n\nWhat was once \"pop\" slowly becomes \"oldies\" or \"classics.\" Distinct genre differences become less distinguishable and music starts to be viewed & classified generationally. We already see it with the terms \"90's music,\" \"80's,\" \"70's\" etc. No one called them those at the time, they're always retroactively-given terms. \n\nWithin what is called \"classical music,\" there are a lot of different eras. There's the \"Baroque Era\" (think Bach), \"Classical Era\" (think Mozart), \"Early Romantic Era\" (think Beethoven), and \"Late Romantic Era\" (Think Brahms), and these are just a few. Before I went through five semesters of music theory, I couldn't tell the difference, but after it's so obvious. \n\nBut in Mozart's time, there were dozens of different, now esoteric genres; to us it just sounds like \"classical.\" His music actually played off the different genres, creating musical \"jokes,\" but the differences are indistinct to all except for erudite scholars. \n\nIt might be funny when Futurama calls Sir Mix-A-Lot \"classical music,\" but really that is probably how it'll turn out. Hip-Hop, Rap, R & B as we know them today might all converge with Electronica and Pop to just be \"Late 20th and Early 21st century music.\" Or perhaps it will all be combined to be \"Early Electronic Music,\" since electric instruments (keyboard, synth, electric guitars, etc) are all crucial elements to these genres. \n\n**This is probably a super round-about way to make my point, but my point is this:** what we call \"Classical\" music is really a collection of different genres of music from centuries ago. With the advancement of technology, like electric instruments, recording equipment, music videos, etc., the tastes of music have changed dramatically over a relatively short period of time (~60 years), and most people just aren't that interested in the old genres. \n\nDon't get me wrong, some people still get popular composing new \"classical\" music, but the only people who listen to these were in wind ensemble or orchestra in high school and college. Like, middle school orchestra (where most classical nerds first get exposed) is literally keeping classical music alive. I'd estimate 99% of \"classical\" music lovers come from there, and now we're seeing school budget cuts that are cutting these out of schools left and right. If no one gets exposed to classical music, then no one will want to listen to it or compose it. Go to a classical concert sometime. It's mostly old people, who listened to post-great-war classical music growing up. Like that shit was on the radio. \n\nWhy have tastes changed, you might be asking? Well, \"Classical\" music as we call it now spanned at least 260 years, and upwards of 800 if you include more eras than I previously mentioned. The styles have been nearly exhausted. We need new, fresh stuff. Plus, a lot of people say we're in a \"golden age\" of technology, and that has had a huge impact on music, from the sweet melody of the theremin to the nasty orchestral hits of the synth. (Just realized I kinda said this already, o well)\n\nAnother question this question raises is what makes \"pop music\" popular? Well, the industry is excellent at selling music, which in part means convincing consumers that they like what the industry is trying to sell. It's not all about garage band musicians campaigning to fame like we like to think it is. Look at Backstreet Boys & N'SYNC, where producers held auditions. Look at Adam Lambert, Kelly Clarkson, and Carrie Underwood, all contestants from a TV show. \n\nLook at [Max Martin](_URL_0_), who basically writes all the pop songs for everyone, including \"Oops!... I Did It Again\", \"Everybody (Backstreet's Back),\" \"It's My Life,\" \"Since U Been Gone\", \"California Gurls\", \"Teenage Dream\", \"One More Night\", \"We Are Never Ever Getting Back Together\", and \"Beauty and a Beat\", just to name a few. \n\nWhether it's American Idol, Disney, or a handful of producers, the industry owns today's pop music. If they decide classical music is back in, then everyone would probably buy into it and start listening to classical music again (not really, but they do have a ridiculous amount of power here.)\n\nLastly, a *huge* drawback to composing for classical music is that it's really fucking hard to master. There are a shit-ton of rules, and easy mistakes that can make it sound like crap. Parallel fifths and octaves, pesky hidden parallels, and tons more I don't even remember. You can get away with such errors in contemporary music and it sounds fine, but try it in these genres and it's hideous. Also, if you want to compose for an orchestra, you have to be a pseudo-expert at each instrument you compose for, which could be thirty different instruments. You have to have an idea of which instruments on which chords with which voicings would blend to make what kind of sound. \n\nSo, it takes a lot of training and education, a lot of practice, so if someone wants to write in it, they have to have undying passion for it to keep at it after 10 years of failure in order to get anywhere good at it. It's not necessarily harder than composing more contemporary styles, as post-production mixing and mastering have similar learning curves, the only difference is that \"classical\" music isn't that popular anymore. There's much fewer people who are passionate about classical music enough to go through all that, as compared to pop, hip-hop, rock, etc.\n\nAnyway, I have to get up in 4 hours. But this was fun!\n\n",
"They first must die."
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3c3ie7 | why can my internet easily load a 1080p youtube video but then struggle to load a _url_0_ stream on low quality? | explainlikeimfive | http://www.reddit.com/r/explainlikeimfive/comments/3c3ie7/eli5_why_can_my_internet_easily_load_a_1080p/ | {
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"When you download or stream something off of the internet, you have your own connection line and you are connecting to a server with its own connection line, the maximum speed of this connection is as fast as the slowest line. In most cases, you have the slowest line, because most websites are hosted in dedicated data centres. But sometimes, due to poor maintenance, high traffic or (most commonly) low budget, you are the faster, so the connection is slower than the maximum speed of your line.",
"Depends on which Twitch channel you're trying to view.\n\n\nTwitch and Youtube have a download/upload speed on their Internet connection. Youtube will give everyone the same amount of their upload, making it a good experience regardless of which video you're viewing.\n\n\n\nTwitch on the other hand, will offer less of their upload to channels that doesn't have a partnership. Watching a Twitch-stream with 5-10 viewers will be laggy on low quality. But watching a partnered streamer in 'high/source' with 1000 viewers will be flawless. ",
"I recently had this issue and found out that my ISP was throttling my video download speeds. You may want to check out some online tests for detecting traffic shaping, or try out a free VPN like VPNGate to see if it provides better results.",
"Because Youtube is compressing the video quite heavily, unlike twitch, which has to stream it right away.",
"Though most previous answers are true in most cases, twitch is a special case. \nI watch a lot of LoL event related streams on twitch and have to switch from FireFox (which is my main browser) to chrome, specifically for twitch. \nThe site is insanely resource intensive and it has nothing to do with bandwith/routing in most cases. \nFor example, try turning the twitch chat off and you'll nice the stream suddenly becomes a lot smoother if you were having problems before (note: none of these issues are present on chrome). \nSomehow FireFox can't handle twitch well at all where the other browsers can (I can probably speculate on it but that would do no good, for example outside of the dev build firefox has no multicore support that's one thing). \nAnother fun thing I noticed was watching streams on Youtube and not being able to fastforward/rewind properly on any browser but Chrome. \nAnyway, if you're watching event related streams and you have a Youtube option you might want to check that out instead of twitch since they support 60fps nowadays (when the source is streaming at 60fps). \n \ntl;dr: twitch in itself is quite a heavy webapp to run especially when you're watching a top viewed stream where the chatbox is flooded with text. In my experience FireFox deals with this site the worst.",
"There can be multiple causes and some of yhem can coexist. \n\nThe largest issue at play when it comes to twitch is that Twitch does not have the time to compress video very well. Twitch barely has time to compress it at all. \n\nYou see, the whole thing with streaming is that people expect to se the video live and as such they expect to be able to interact on the fly. This means that Twitch has to minimize the delay between them recieving the stream and them sending it out to you. \n\nCurrently the delay is about 10 seconds. In that ten seconds they have to recieve the stream, transcode and compress it, and send it back out. \n\nIt is very difficult to transcode a compress a video by any significant amount in ten seconds. It is even more difficult to compress a high bitrate stream down to youtube bitrates in ten seconds. \n\nThis is why you can watch a 1080p youtube video so easily compared to a twitch 1080p stream. There is a verly large difference in the amount of data being sent to you. \n\nWhat's more is that Twitch is not as big an operation as youtube is. It may not have as much bandwidth to play with as twitch does. Considering that it has to send out a data stream to every person that is downloading the stream, they really freaking chew up bandwidth. \n\nYoutube's bitrate is lower because they don't have the same restraints in terms of transcoding. They can encode their videos more efficiently. I suspect that they also have a lot more cpu horsepower to play with. Perhaps also more server locations which allows for more efficient routing of data. \n\nNow one other issue you might face is thatthe internet is inneficient. The servers that handle the internet traffic send data on the most direct route between two points. They don't do much in thr way of load balancing. This means that the second and third most direct routes may not have much traffic despite the most direct routes being nearly saturated. \n\nThis can be solved by using a vpn. Vpn's change the routing of traffic and make it more efficient. It means that while you might have slightly higher latency, you won't have to deal with packets of data being dropped being the most direct route is full. \n\nOn the other hand, if the various service providers would put load balancing on their servers, the effective bandwidth of the internet would increase. They probably do this to an extent, but obviously not enough. If they did enough then vpn's would lose a major selling point. ",
"In the ELI5 form: youtube has many dedicated servers and high quality connections that allow multiple users to use their servers at the same time with not much problem on their end but twitch streamers are generally people with just normal home internet and depending on the amount of other people watching and the kind of internet they have also combined with whether or not they even have a good router to constantly send enough data out to the twitch server it can take some time. Tldr; youtube saves it on its servers and you view it easily where twitch streamers stream constant update to servers for you to view",
"\"Your comment has been removed since it has been detected as a personal anecdote.\"\nWow, bull. The top commenter isn't even right, he's just not technically wrong. He basically just said it's because youtube has faster servers.\n\nThe real reason is because youtube splits up the video into chunks, and gives you a lower quality so that it's always fast. They have state of the art algorithms that compress the data into high quality but low data. each image chunk starts with a picture, then the rest of the frames are pixel deltas (black images with the only pixels being the changes from the first frame to what the next frame should be) that, combined with multiple computers streaming multiple qualities to you helps a ton. Twitch's main problem is that their algorithms are bad at retaining quality and compressing data, so they don't want to make the quality really crappy, and the speed suffers. That, and the connection depends on the streamer, which will usually be slow, as your upload rate is way slower than your download rate.\n\nThis is obvious to most programmers, including myself, but here are some links:\nVideo frame refrence patent from google:\n_URL_1_\nSplitting of their audio and video (to keep high quality audio with low quality video, because audio uses more bandwidth)\n_URL_2_\nMicrosoft version of low quality to high quality (couldn't find google's)\n_URL_0_\n"
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[],
[],
[],
[],
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[],
[],
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"https://www.google.com/patents/US6637031",
"https://www.google.com/patents/US6075561?dq=Original+Assignee+Google+Inc+video&hl=en&sa=X&ei=8nSZVfmDBsfEsAXp2paYDQ&ved=0CCQQ6AEwAQ",
"https://www.google.com/patents/US8625033?dq=Original+Assignee+Google+Inc+video&hl=en&sa=X&ei=TnWZVbuNJ8nItQWbh7-wBQ&ved=0CDkQ6AEwBA"
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3e9jtj | how can netflix release new series' all the time when traditional media channels could barely do 5 per season? | explainlikeimfive | http://www.reddit.com/r/explainlikeimfive/comments/3e9jtj/eli5_how_can_netflix_release_new_series_all_the/ | {
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"One big difference is that Netflix doesn't have a schedule to keep. Traditional TV has to fill up 7 days a week, so there is a finite number of hours of time to air a show. ",
"Traditional media does not only release 5ish new shows per season because that is all they can manage, they release that many because it is a calculated risk. Some shows are going to make money, some are going to cost money. Additionally, there is a finite amount of time on their channel and you can only capture so much of your audience's time.\n\nAll of that goes into deciding how many shows a traditional media channel produces. "
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2sqasp | why do some cars (i.e. french) have yellow coloured fog lights? | Why do some cars have yellow tinted fog lights, instead of just normal white light? It seems to be a european spec. thing, and someone once mentioned something about the blue shift of light being involed. How does that apply? | explainlikeimfive | http://www.reddit.com/r/explainlikeimfive/comments/2sqasp/eli5_why_do_some_cars_ie_french_have_yellow/ | {
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" > The fact is, in late 1936 lawmakers in France put forth legislation requiring road-illumination lamps (headlamps, fog lamps, etc.) on all vehicles to emit selective yellow light. This legislation was based on advice from the French Central Commission for Automobiles and Traffic, which in turn was based on experiments done by the French Academy of Sciences, concluding that selective yellow light is less glaring than white.\n\n_URL_0_",
"Like you're five...\n\nThe yellow light does not reflect off the water as readily as the blue in white light does. It more effectively cuts through the bad weather and shows you the road. ",
"It works better for fog... simple as that. I've tried both and yellow is significantly better.",
"Since 1993 most new cars are fitted with white lights. Usually, cars with yellow lights are quite old.\n\nBefore 1993 you would get fined for not having yellow lights.\n\nThen why yellow lights ? /u/aragorn18 and /u/intrepidzephyr answered that part :D .",
"It was supposedly because yellow lights are better in fog than regular white light. In reality, there is no evidence to support the assertion that yellow light is less glaring or better at illumination in foggy conditions.\n\nAs [Professor Craig Bohren of Penn State University](_URL_0_) puts it, There are two possible explanations for yellow fog lights. One is that the first designers of such lights were mislead because they did not understand the limitations of Rayleigh's scattering law and did not know the size distribution of fog droplets. The other explanation is that someone deemed it desirable to make fog lights yellow as a way of signalling to other drivers that visibility is poor and thus caution is in order.\n\nAnother likely theory is that it was a form of market protectionism by the French.",
"When in the US, I was surprised by the color of turn lights (red). Everywhere in Europe these lights are orange.\n\nedit: as some figured out, I was referring to the back turn lights.",
"The longer wavelength of the yellow color is the reason. It manages to penetrate and stay on for extended distance, long after the rest of the colors in the spectrum dies off in the fog. ",
"Most racecars that do night competition use yellow lights as well.",
"Blue wavelength is shorter than yellow wavelength, and is more readily scattered by airborn particles, which is why the sky is blue and taking long distance photos is more likely to show a blue haze. A yellow fog lamp lens absorbs the blue component of white light so only the red and green components can get out.\n\nRed would travel with least scattering by the fog, but if only red were let through then we'd get lower contrast with the surroundings and contrast is important. Yellow is technically the most 'visible' color to us, so whatever yellow light gets reflected back off of surroundings will be most visible. So the choice of yellow is a best balance of reducing scattering and increasing overall visibility.",
"To clarify what has been stated a pure white light would tend to illuminate the fog directly in front of the car vs the objects behind it"
]
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| []
| [
[
"http://www.danielsternlighting.com/tech/lights/light_color/light_color.html"
],
[],
[],
[],
[
"http://www.newton.dep.anl.gov/askasci/phy99/phy99xx4.htm"
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19diij | why the url is so long when i do just a simple google search? | explainlikeimfive | http://www.reddit.com/r/explainlikeimfive/comments/19diij/eli5_why_the_url_is_so_long_when_i_do_just_a/ | {
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"When you do a \"simple search\", it's only simple to **you**. You're expecting Google (or any other search engine) to *understand* what you mean, and find the content that relates.\n\nIt does a bunch of things, like determining your language, filtering NSFW content, determining possible corrections (for spelling mistakes, etc), and a host of similar functions.",
"Its passing a lot more information to the search engine to customize your output. For example, you might see \"safe=off\", that means that the safe mode is off.\n\nThe actual content behind your query is after the \"q=\"."
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5xoy60 | how stealth operations really work since most depictions of silencers/suppressors aren't realistic | I've read/seen from different sources that silencers and suppressors on weapons don't actually "silence" gunfire, and shots are still quite loud. Since most depictions of stealth operations in videgames and movies depict teams quietly picking off hostiles while making their way through an area so they don't raise any alarm, how do these situations go in real life? | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/5xoy60/eli5_how_stealth_operations_really_work_since/ | {
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"Suppressors dull the sound of a gunshot slightly, but more importantly they dull its ability to echo, and they dull the recognizable 'pop' or 'crack' of a gunshot, turning it into a some kind of 'chiss', 'tssk', or if you use subsonic rounds, 'chack'. \n\nThese two features, less echoing and less recognizability, are used by stealth teams to dispose of one sector of enemies without the other sector knowing about it on-time and arriving to reinforce them. Suppressed weapons also make it harder to tell where the operator is, thus strike teams will quickly confuse their opponents as they wipe them out.\n\nOverall, movie depictions are naturally not that accurate. Stealth teams rely on coordinated strikes to remove groups of enemies without raising the alarm, and even then teams must have contingency plans in the rather likely case that someone radios one of the dead or sees the team moving through. Real stealth operations are extremely fast and fluid because every second not spent killing is a second someone sees what's going on. There will still be quite a bit of sound, but it will be concentrated and not drawn-out. ",
"Sometimes you want to go into an area and do some sneaky things. People in these areas don't want you to do anything in these areas, especially sneaky things. Sneaky people use silencers to make their guns quieter and harder to tell where it came from. Bullets move real fast and make a noise just from moving. To solve this, smart people who are also sneaky use bullets that move slower, it still pretty fast, to remove even more noise from shooting. ",
"I recommend you take a look at the [Welrod](_URL_1_), It's a suppressed pistol that was designed during WWII and was known to be used in the Gulf War. [(Forgotten Weapons' video)](_URL_0_). According to Wikipedia, the Welrod made a mere 73db when fired (According to [_URL_2_](http://www._URL_2_/noise-level-chart.html) it's slightly quieter than a toilet flushing)."
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[],
[],
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"https://www.youtube.com/watch?v=d12AjvEsaHg",
"https://en.wikipedia.org/wiki/Welrod",
"noisehelp.com",
"http://www.noisehelp.com/noise-level-chart.html"
]
]
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|
71skbf | how does the us make it illegal for its citizens to visit "banned" countries? | Let's say I (a US citizen) take a typical vacation to a "banned" country. Would it be illegal solely because I was *in* the banned country? What charges could the US legally bring against me? | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/71skbf/eli5how_does_the_us_make_it_illegal_for_its/ | {
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"There's usually very little they can do to physically stop you going to a banned country, but when you come back into the country they'll want to know where you've been, and they won't like what you tell them, and there may be consequences.\n\nThose consequences are rarely auto-severe. It'll ruin your week, maybe your month, but you'll be alive and free afterwards, assuming they like the things you say about where you've been.\n\n\"I went to north korea to learn how to cripple the west\" is probably on the list of things they don't want :)",
" > Under U.S. law, the secretary of state has the authority to designate passports as restricted for travel to countries with which the United States is at war, when armed hostilities are in progress, or when there is imminent danger to the public health or physical security of United States travelers. Geographical travel restrictions are rare but have been used by numerous administrations in the past for countries where it has been determined to be unsafe.\n\n_URL_0_\n\nEdit: You would not be allowed to depart for the banned country from a US port or airport.\n\nYou may be punished with up to ten years in prison. Probably not for attempting to make the trip, but for circumventing the ban - say you travel from a third party nation to the banned nation.\n\nObviously no punishment until you return to the US. ",
"I mean...they made it illegal because Congress passed a law stating that the Secretary of State can say it's illegal. That's the \"how\". That's how they make anything illegal.\n\nThe \"why\" is for various reasons. Sometimes it's to prevent people traveling to war zones for nefarious purposes. Sometimes it's because we want to exert pressure on that country to change something it's doing.\n\nAnd yes, for example, if under the original embargo it was determined that you had traveled to Cuba, you could in theory be jailed simply for going there. You'd be charged under the Trading With the Enemy Act of 1917, and possibly other laws depending on what you did while you were there."
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[],
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"https://www.usatoday.com/story/news/politics/2017/07/21/u-s-ban-americans-traveling-north-korea/498714001/"
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[]
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|
|
58cls5 | how do the speakers and mics of waterproof smartphones work (like the ip67 iphone 7)? | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/58cls5/eli5_how_do_the_speakers_and_mics_of_waterproof/ | {
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"Most are \"water resistant\" meaning you can't keep them submerged for long - accidental drop in the toilet or sink, no problem. The internal design features very thin filaments that don't obstruct sound waves much. Notice how the iPhone 7's design features a much louder speaker? I assume it would be even louder without the water resistant material ",
"Usually there is a barrier, a thin sheet of Mylar. That's why there isn't much depth rating, serious pressure differential would fail the membrane. A little extra amplification, adjusted to offset the dampening of the protective film, cover up the existence of the barrier.",
"TL;DR) The Speaker and Microphone cutouts have this mesh on the inside that might be made of some kinda metal, but its overall purpose is to prevent dust and water from passing through while allowing sound easy access, though. \n\nWell, most of the internal components to this feature are largely speculative (glues, rubber seals...) and patented improvements. The most notable improvement to water-resistance came from the virtual button, previously this area was **very** susceptible to water access and simply replacing that did more than you would expect for the water resistance of the chassis in general. Some of the speculated improvements come from special glues to tightly seal the case, rubber seals around the ports (SIM tray), as well as these seals around *important* parts of the circuit boards for extra protection (might have also been on 6s...still worth noting). As with the bottom of the phone inside almost all of the components down there you will find some kind of ingress protections, the lighting port which formally had some kinda adhesive now comes with a heavy duty rubber seal for IP reasons. The speaker and microphone have a mesh that is aligned tightly to the openings in the case, I can't say for sure what kind of mesh it is but and an educated guess says it's some sort of Metal Mesh designed to prevent dust and water from getting through while still letting sound pass through unabridged.\n\nFun Fact) On the Apple Watch Series 2 the Speaker/Microphone port actually has a pushing mechanism that it uses to literally expel water trapped inside when you exit the pool. "
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6ptsv2 | how does fostering kids work? | I always hear about how foster kids are sometimes abused and I want to know what the foster system works. Is it a job or do people get chosen like they do for jury duty? Is it volunteer work, and if so, why are there so many people volunteering to abuse these kids? | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/6ptsv2/eli5_how_does_fostering_kids_work/ | {
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"You sign up. Social services does some routine investigations to qualify or disqualify you. Then then place a child with you...and you get a monthly stipend of $600-800/mo plus some amount of foodstamps to feed the kid. \nTheres a caseworker assigned to you that has waaay too many foster kids to pay proper attention to each case. When theres a complaint or problem they respond and evaluate whether there is an actionable issue or not. \nAbuse happens sure. BUT most foster parents take good care of the kids they foster. Most kids in foster care are a lot better off than they would be in group homes. Like anything you hear more about the failures and flaws than the success stories. ",
"Also, for clarification, if a person or family wants to foster a child, they apply to do it and the agency will do a home and background check prior to decide if they're fit to become parents. It's similar to adoption, just without the commitment. Hope this helps!",
"I'm sure there's someone else that can explain this better. \nThere are two types of people that foster kids. The people that truly care about the children and the ones that are only doing for a paycheck. \nThe latter are the ones that foster for all the wrong reasons and may abuse the children. Some people believe that because they are providing homes to these children that can do with them whatever they please. \nFostering is voluntary and the foster parents receive money from the state for the child's needs. \nThere are also private foster care companies that receive money from the state or local governments based on the number of children they place in homes and the business (dealing with the lives of children and all) is just as worrisome as it sounds. ",
"The money it pays is tax free, it works very well to supplement your income. Along with the monthly compensation the kids would get vouchers for a lot of expenditures (at least in Alberta Canada they did) new bikes, school supplies, clothing vouchers the only thing that would really come out of your cut was housing, food, and maybe their allowance. \n\nMy parents did it to supplement their income. They would take care of short term high needs kids, and every once in a while a couple of long term kids would settle in. Most went on to go home, get adopted, or settle with next of kin aunts/uncles/grandparents. Over the years probably close to 50 kids came through the house. I hate to admit it but it made me extremely territorial in my youth. We would get a lot of kleptomaniacs, I suppose that's not surprising, a lot of kids come from nothing and stealing just becomes second nature. We also had a lot of special needs kids with all variations of learning disabilities. One of the better kids we took care of had some serious handicaps which I couldn't pick up on at the time but flash forwards 10 years and the kid is still counting on his fingers at age 15. Two of the worst kids we ever took care of were manipulative enough to break at least one marriage. You name it I've probably seen it; babies with drug withdrawal, ADHD, hyperactivity, food hoarders, one kid had burn marks where someone had snubbed out a cigar on his back more than once, kids getting into shit fights (fights where they would throw their feces), you heard jokes of kids ripping up carpet turns out that's a thing, another kid stabbed a social worker with a knife, a pregnant teen stayed with us for a couple months she went on to kill her baby because she didn't want it to go through the social system like she did."
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aea82m | how far would you have to fall for the drop to be fatal on the moon or another planet due to the lower gravity? what about higher? | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/aea82m/eli5_how_far_would_you_have_to_fall_for_the_drop/ | {
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"This question is a bit hard to answer, because how far a fall has to be to be \"Fatal\" can vary pretty widely. Tripping can kill you if you are unfortunate. Other people have survived falling jaw dropping distances.\n\nOne thing you can compare, is that the acceleration of gravity on earth is 9.8 meters per second, per second. That is to say, every second you are falling, you fall 9.8 meters per second faster than the last second. So after two seconds you are falling at 19.6 meters per second (ignoring atmospheric effects).\n\nOn the Moon, the acceleration is 1.62 meters per second, per second. \n\nSo to reach the same speed as \"Falling 2 seconds on Earth\" you'd have to fall on the Moon for about 12 seconds. \n\nMeanwhile, on Jupiter the acceleration is 24.79 meters per second, per second, so it would take less than 1 second to fall at the same rate. \n\nEdit: For completeness sake, I also want to mention that as noted above, this ignores atmospheric effects. They add a further complexity, as atmosphere can limit your 'top speed' and change how fast you reach it depending on things like orientation."
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9vejn6 | how does the cornstarch and water mixture behave like a solid and a liquid? | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/9vejn6/eli5_how_does_the_cornstarch_and_water_mixture/ | {
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"The particles of corn starch are very tightly packed together in the water; if you move them slowly, then they have enough time to move out of the way without much resistance. If you try to apply rapid force, there isn't enough time to move and they react like a solid brick of corn starch."
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2xqrav | how can companies create a product, such as coffee, and ensure the product stays the same over time, but different than competitors'? | A coffee bean comes from a plant. How can a company control what the plant produces? How can a company have a coffee bean that is different from another's company?? Does each company have their own strand? I understand that they may process it in their own way, but how many special processes can there be? | explainlikeimfive | http://www.reddit.com/r/explainlikeimfive/comments/2xqrav/eli5_how_can_companies_create_a_product_such_as/ | {
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"Expert tasters, trained chemists, botanists knowledgeable in the field of coffee beans, experienced roasters, more chemists, meteorologists who recorded the weather patterns where coffee was grown and can predict the effects of weather upon yield, plus a chemical \"profile\" of the end product... all that and some luck gives quality and identifiable character. \n\nSpecial processes? Roasting requires control of temperature and time. Roasting by itself is not special, but how those elements are applied in light of all the other factors makes a huge difference.\n\nThat's how. ;-) "
]
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3ell4a | why is mexico so against the mexico/us border fence blocking illegal immigration? | explainlikeimfive | http://www.reddit.com/r/explainlikeimfive/comments/3ell4a/eli5_why_is_mexico_so_against_the_mexicous_border/ | {
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"A lot of the people illegally entering the US from Mexico aren't Mexicans. They illegally entered Mexico to get to the US. Mexico would rather they keep going and get into the US rather than stay in Mexico.",
"Simply put, it's somewhat humiliating and degrading for Mexico. \n\nGovernments always wish other countries allow easy access for their citizens. That's kind of their job, to please their citizens, and to be respected.",
"Do you expect them not to be a little offended that people here want to build a 2,000 mile long wall at great expense in order to keep them out? ",
"Contrary to public perception, a ton of illegal immigrants only come to the US to work for part of the year, then return to Mexico with the money they made. This is a major source of cash for the Mexican economy, and it will really hurt them if migrant workers can't cross over."
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7j5sfq | given that the universe does not have a center, and all positions are relative, what's wrong with saying earth is the centre and that the sun revolves around it? | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/7j5sfq/eli5_given_that_the_universe_does_not_have_a/ | {
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"text": [
"The Sun's trajectory relative to all the other stars is smooth. The Earth runs rings around this smooth, continuous line. So do the other planets.\n\n\nUsing all the other stars as a frame of reference, [the paths look like this.](_URL_0_) (Edit: as another user has pointed out, this picture is greatly oversimplified, but it makes the point accurately enough.)",
"Nothing, we do it all the time. Every time you say you are driving at 75 mph, and not something closer to 70,000 mph, you are implicitly assuming the earth is stationary and everything moves around it.\n\nProblems arise when you assume choosing the earth as the center is somehow special or meaningful. If you are guiding a space probe to Jupiter, assuming everything travels around an insignificant speck like the earth is pointless and creates unnecessary complication. Far better to use the Sun and/or Jupiter as a reference on such a mission. And when you get further out, saying the motions of galactic super cluster is governed by a tiny rock a billion light years away, that is just idiotic.",
"Both the earth and the sun influence each other through gravity, and the center of the orbit is not center of the sun. However, the sun's gravitational pull is so much more powerful, the center of the orbit is inside the sun. \n\nSo, we're in the Sun's gravity well; the sun isn't in ours. And when referencing every other celestial body in the solar system except for our moon, things orbit the sun. So trying to describe everything involving orbits by putting the earth at the center makes things very difficult. "
]
} | []
| []
| [
[
"http://www.slate.com/content/dam/slate/blogs/bad_astronomy/2013/03/04/sadhu_helicalmotion1.jpg.CROP.original-original.jpg"
],
[],
[]
]
|
||
1el7iv | why do we have "middle c" and cdefgabc as the major scale with no flat/sharp notes? why not start with a? | I hope I phrased that well. | explainlikeimfive | http://www.reddit.com/r/explainlikeimfive/comments/1el7iv/eli5_why_do_we_have_middle_c_and_cdefgabc_as_the/ | {
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"score": [
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"text": [
"If you were to start with A, and ascend the scale with no flats and sharps you would get a natural minor scale. (in fact it's the C natural minor scale) A major scale goes in steps. those steps being Tonic, whole, whole, half, whole, whole, whole, half. All major scales follow this pattern. It just so happens that the only way to follow this scale pattern and still have zero sharps or flats, would be if you started on a C natural. Hope this helped",
"So far as I can tell from [Wikipedia](_URL_0_), the reason for this dates back to the 6th century, which was the time of the first recorded use of letters to represent notes.\n\nAt the time, musical instruments were far more restricted, and there were only two octaves in use. The notes which were used at the time were assigned to the first 15 letters of the alphabet.\n\nAfter that, the idea of repeating letters began to be used, with a-g (yes, lower case) being used for the first octave, and aa-gg being used as the second octave.\n\nAs disco_shit says, if you start with A and don't use sharps or flats you get A-minor. I'd guess that the notes used in that period were the notes which we now consider to form the A-minor scale. My knowledge of music history isn't enough to fill in the gaps with confidence - but I think that's why we have the strange situation where we start the most simple major scale with the third letter of the alphabet."
]
} | []
| []
| [
[],
[
"http://en.wikipedia.org/wiki/Note#History_of_note_names"
]
]
|
|
20rg1m | what happens to unused, outdated military weapons? | As countries continue to research new military equipment but does not use them, what happens to the old ones? | explainlikeimfive | http://www.reddit.com/r/explainlikeimfive/comments/20rg1m/eli5_what_happens_to_unused_outdated_military/ | {
"a_id": [
"cg61314",
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"score": [
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5
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"text": [
"Usually they're either destroyed or sold to other countries. Outdated to us might be brand new to them.\n\nRarely, they are surplused to civilians and sold in auctions.",
"Some things are sent to reserve units. Some things are given/sold to poor foreign allies. Some are put into long-term storage for \"oh shit, we need to give everyone a rifle\" wars. Some things get sold as surplus to civilians.\n\nThe rest gets broken down and scrapped."
]
} | []
| []
| [
[],
[]
]
|
|
65gpya | why do we get a chill when we bite metal like a fork or a spoon? | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/65gpya/eli5_why_do_we_get_a_chill_when_we_bite_metal/ | {
"a_id": [
"dga5d31",
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"text": [
"I don't think that happens to everybody. Do you have metal dental fillings?",
"From what I have read in an old article it's because your teeth don't have nerves around the edges and, since your teeth are natures barometer when it comes to how long you'll live (in the past at least), 'chills' are your body's reaction to something that may damage your tooth enamel. "
]
} | []
| []
| [
[],
[]
]
|
||
6ntgek | does a short-sighted person have 20/20 vision when looking at something up close (without glasses)? how does one measure this? | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/6ntgek/eli5_does_a_shortsighted_person_have_2020_vision/ | {
"a_id": [
"dkc2mux"
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"text": [
"20/20 vision is a term used to explain how well you can see something at a distance. The first \"20\" means you can see something clearly at twenty feet. The second \"20\" is the distance that someone without bad eyes would see it at. So with 20/20 vision, you can see something that is twenty feet away perfectly clearly, which is what a normal person can see. But if your vision is, say, 15/20, you have to be fifteen feet away to see an object clearly that a normal person could see at 20 feet. \n\nSo here's how your eye works. Light comes in and is refracted, or angled, as it passes through your pupil. If your vision is fine, it is refracted correctly into the part of your eye that interprets it and decides what you're seeing. But if you are nearsighted, your eye is too short from front to back, so some of the light misses the target, or gets jumbled around. Your brain takes this information and in an attempt to explain it to you, it makes a \"best guess\" of sorts that results in blurry vision. \n\nThink about a spoon versus a melon baller or an ice cream scoop. Hold each one directly under a running sink faucet, about a foot from the tap. The spoon is going to spray water everywhere, but it isn't going to project it very far out directly because the curve is less sharp. The melon baller, on the other hand, will have much more range and won't spray as wide, because the curve will focus everything in one direction. The spoon is a nearsighted person. \n\nKeeping with that analogy, if you move the spoon close enough to the faucet, it will generally begin to act just like the melon baller because the water is hitting a smaller surface area on the spoon. What happens in your eye, though, is the angle at which that light is refracted changes as you get closer to an object, and will eventually get to a point where it is basically as good as a normal person's vision. And then it will keep going. But your brain can only see something so clearly, so it throws that extra information away. This is why if you wear glasses, your eyes will take a moment to adjust when taking them off to read. \n\nIn case you're interested, the opposite is what happens if you're farsighted. The eye is too long. So at, say, thirty feet, their eye might be seeing things the same way a nearsighted person sees it up close where the brain is discarding extra information because it can't create a sharper image. But as the object gets closer, the angle of refraction causes some of that information to miss the target or bounce back out, creating a blurry image as your brain tries to make sense of the information it is getting. \n\n"
]
} | []
| []
| [
[]
]
|
||
38z7x2 | when lying in bed, why do we sometimes feel the urge to raise an arm straight up in the air? | I know I'm not the only person who gets this strange urge. | explainlikeimfive | http://www.reddit.com/r/explainlikeimfive/comments/38z7x2/eli5_when_lying_in_bed_why_do_we_sometimes_feel/ | {
"a_id": [
"crz1xfj",
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"score": [
4,
2,
4
],
"text": [
"Yeah, happens to me too\n\nI think it's one of those actions your body takes to prevent itself from atrophy. ",
"I get this feeling but it's not random. It's usually when my arms asleep and I need to move it around a bit. Never just had an urge to do so",
"I get that urge when my breathing is too shallow. (Like, say, if my nose is clogged from allergies.) Raising the arm above the head seems to lift pressure off the lungs and make breathing easier."
]
} | []
| []
| [
[],
[],
[]
]
|
|
63wtx9 | how does jurisdiction apply to patents? is anything stopping me from copying a patent in one country, and applying to patent it in another country? | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/63wtx9/eli5_how_does_jurisdiction_apply_to_patents_is/ | {
"a_id": [
"dfxm99s",
"dfxmvm9"
],
"score": [
2,
2
],
"text": [
"Nothing other than the treaties between the two countries and the willingness of the patent owner to try to sue you across international borders.\n\nThe gov doesn't actively enforce patents. It's handled in lawsuits in civil court.",
"This is part of the considerations in filing for a patent. If you pursue the patent in several countries, you'll potentially be able to sue in several courts, but you incur more costs and fees. Most companies know where their key competitors are, and file accordingly. If you get a patent for my invention in a country where I don't do business, you might be able to keep me from expanding to that country without paying you off. However, since I'm not doing business in that country, maybe I'm not concerned."
]
} | []
| []
| [
[],
[]
]
|
||
2f2ge6 | the us military has roughly 150,000 people stationed in just 5 "friendly" countries (uk, germany, italy, japan, s. korea). what do they actually do there? | There no war or anything requiring US military in those countries.
What is the day to day life. Is it all day drills to keep fresh in case they are needed for an actual war? What value do the 50,000 US soldiers in Germany provide to Germany?
What value is it to the US to have all those people in Germany instead of in the US? I understand they can mobilize faster being closer, but it seems to be an excessive amount of people and therefore cost to the US
| explainlikeimfive | http://www.reddit.com/r/explainlikeimfive/comments/2f2ge6/eli5_the_us_military_has_roughly_150000_people/ | {
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"text": [
"I'm not 100% sure I understand your question. Are you confused as to what a military base is used for?",
"I'm no expert, but by watching the news during my life I've learned that a lot of our bombers are based in foreign countries as that increases our global reach when we need to bomb something.\n\nAnd in Germany, we have Ramstein Air Force Base, which has a huge hospital. When an American is hurt in the Middle East, they are eventually transferred to Ramstein.",
"There are two main reasons there is such a large American military presence in Germany. Germany is a hub and a strategic location for the American military.\n\n1) Landstuhl Regional Medical Center is the largest military hospital outside the continental United States. Serves as hospital stop for injured American soldiers from Irak or Afghanistan or other countries in those regions. (_URL_1_)\n\n2) Ramstein Air Force Base is the largest U.S community overseas, more than 100 geographically separated units receive support from there. (_URL_0_) And a huge part of the drone warfare is routed through there, Germans are not happy about this part in particular. (_URL_2_) \n",
"They train. That's all the military is (or should be, there is a ton of bullshit as well). Depends on the job.\n\nExample 1: Infantry (11B). Gets up, goes to physical training. Eats, showers, goes to company building. Leadership issues tasks, conditions and standards on whatever the hell is going on that day. Let's say its a range day. Draws weapon from the arms room, gets gear. Gets on truck, goes to range. Pew pew pew. Back to company. Clean weapon. Go home. Beat off in barracks and drink.\n\nExample 2: That fucking guy who sits in S1 and loses your paperwork. Gets up, goes to physical training. Cleans self, eats. Goes to work. Sits in S1. Lose paperwork. Go home. Beat off in barracks and drink.\n\nSummary: The military is a job. You either do your job or train to do your job. You also pick up cigarette butts and get yelled at alot. Join today, its awesome.",
"In Asia, for example, the US air base in Okinawa is in the perfect position for the US to come straight to the aid of Japan, were China or North Korea ever to start lobbing missiles over the pond. Their substantial military presence their is largely used as a deterrent. \n\nThe US also keep a watchful eye over the major shipping lanes in the region, and other crucial geographic locations, so as to make any conflict seem much less attractive. ",
" > What value do the 50,000 US soldiers in Germany provide to Germany?\n\nFat stacks of cash. No seriously, the soldiers and airmen (and handful of sailors) here spend quite a bit of money off-base, significantly contributing to the German economy. There are also a significant number of Germans who work on-base, get paid by the US government, then pay their German taxes and buy German things since local nationals can't shop at the BX and stuff.\n\nOther people are talking about why Germany (as a country) doesn't seem to mind; I thought I'd chime in with why Germans (as individuals) don't mind. In my experience, at least.",
"There's a lot of dumb answers in this thread, and someone who had the right answer is being downvoted. \n\nThe simple truth is that having bases oversees is a strategic advantage. It takes a lot less time to get to Africa from Germany than from America. Quick Reaction Force. It is also about a projection of military power. We *project* military power around the world in order to support diplomatic goals. \n\nAs for why we need 50,000 personnel in Germany-- Obviously it started post WW2, and don't forget that troops in Germany were ABSOLUTELY necessary from a defense/projection standpoint until the fall of the Soviet Union. One could argue that they are still necessary: see Putin's Aggression. War in Europe is not some long forgotten possibility. It can still happen. Now, most of the people in Germany are not actually front lines invasion force. I'd guess about 10% are, maybe. The rest, as someone else has stated, are support personnel ranging from the medical center at Landstuhl to the Air force personnel at Rammstein, which are able to support operations happening all around the eastern hemisphere. \n\nIn Japan/Korea/Guam/etc.. it is about power of the Pacific. The Pacific Rim is a huge geographical area, nearly impossible to control. There are extremist terrorist groups in South East Asia, so that is a concern. There are natural disasters, which the US forces attempt to assist in relief efforts. I have never done this, so I have no idea how much help they can actually offer. \n\nSo what value is it to the US? HUGE VALUE. \n\nWhat value is it to ze Germans/Japanese/Koreans etc..? Well, defense would be the obvious answer. Cheaper Training of their troops by superior forces, so money plays into it for some. For newer nations, a US presence can provide legitimacy to a government (Africa). \n\nAs to what they do all day: The exact same thing they do in CONUS, for the most part. I've spent time in Hohenfells, doing the same shit I did in 29 Palms and Ft Hood. Training. Working long hours. Working with foreign security forces, training them, drinking with them. There are 1000 different jobs in the military, so it's impossible to answer \"What do they do all day\" with anything other than \"Work, train, eat, sleep\".\n\nDon't forget, the military and government move VERY slow. It takes years to establish these bases, there's a lot of infrastructure. It takes even longer to remove them sometimes. Plus, you never know where the next conflict will be. Smart money is on Africa right now, but Eastern Europe is looking pretty hot too. The whole point of the military is to be ready for any conflict, which means having assets as wide as you can with out getting over stretched. \n"
]
} | []
| []
| [
[],
[],
[
"http://en.wikipedia.org/wiki/Ramstein_Air_Base",
"http://en.wikipedia.org/wiki/Landstuhl_Regional_Medical_Center",
"http://www.dw.de/berlin-powerless-to-challenge-us-drone-operations-at-ramstein-air-base/a-17545327"
],
[],
[],
[],
[]
]
|
|
5rd1jq | if heat rises, why do mountaintops often have snow in places like california and hawaii? | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/5rd1jq/eli5_if_heat_rises_why_do_mountaintops_often_have/ | {
"a_id": [
"dd6c6bv",
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"score": [
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"text": [
"Because they are higher in elevation. The higher you go in elevation the colder the air temp becomes. The earths crust traps some of the energy from the sun and keeps the area closer to the ground warmer. There is also less wind resistance high up in the air due to lack of trees, buildings, animals, landscape, and so forth. The lack of wind blocking objects means the wind is free to blow at high speeds with little resistance. \n\nEdit to add extra info: The higher you go up in the sky (away from earth) the more oxygen is lost to the vacuum of space, resulting in lower temps. ",
"Hot air rising is the exact reason why there is snow on mountain tops. Imagine a little cube of air at the ground surface. There is some amount of water vapor in this cube. The air is hotter than the surrounding air (and is therefore less dense), so it begins to rise. As its rising, the pressure of the air is decreasing, so it begins to expand. As its expanding, the temperature starts to drop (roughly at 1 degree Celsius per 100 meters of lift). Now, as the temperature is decreasing, the cube is also losing the ability to store water vapor. Eventually, the cube will rise high enough to where it will no longer be able to contain the amount of water vapor it started with, and it will begin to get rid of the excess water through precipitation (snow). Generally, by this point, the temperature will be low enough so that it will stop rising. "
]
} | []
| []
| [
[],
[]
]
|
||
6h806c | what kind of laws states can make for themselves, contradicting federal law, and to what extent? | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/6h806c/eli5_what_kind_of_laws_states_can_make_for/ | {
"a_id": [
"diw6nol",
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"score": [
2,
8
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"text": [
"None contradicting federal law. Federal law supersedes state law. Enforcement can potentially be another matter, for example current marijuana laws, contrasting state to federal. \n\nThe supremacy clause (in the Constitution) states that the federal government wins in cases of conflict of law, if they decide to force the issue.",
"Generally, state laws can't directly contradict federal law. More precisely, if a state's law does contradict federal law, then the state law isn't enforceable. \n\nThe federal government is generally restricted to laws on topics referenced by Article I, Section 8 of the Constitution. Some are pretty clear cut but others can fall into grey areas. When that happens, the Supreme Court decides what's constitutional and what isn't.\n\nNone of this stops states from passing unenforceable laws as acts of protest against a federal-level law (with varying success). For example, the states that have made marijuana legal are in direct contradiction with federal law but, when those laws were first passing, the executive branch opted not to pick that particular fight even though the federal laws prohibiting marijuana override state laws allowing it."
]
} | []
| []
| [
[],
[]
]
|
||
28khn0 | the talk about youtube banning content from indie music labels | the way it's being written up in articles like [this one on the verge](_URL_0_), I'm having trouble believing that the situation is really what's being reported - youtube is removing content from its own site in an attempt to strong-arm labels into doing something?
what's *actually* happening? are people just extrapolating or exaggerating? | explainlikeimfive | http://www.reddit.com/r/explainlikeimfive/comments/28khn0/eli5_the_talk_about_youtube_banning_content_from/ | {
"a_id": [
"cibyvnd"
],
"score": [
2
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"text": [
"I would take this with a grain of salt. They're a business, they will do what makes them more money. They already had a rocky patch with the copyright violation fiascos a few months ago, and I have a feeling the community would raise their voices if they did anything too extreme this time around as well."
]
} | []
| [
"http://www.theverge.com/2014/6/17/5817408/youtube-reportedly-block-videos-indie-artists"
]
| [
[]
]
|
|
6c15gi | why do emergency vehicles sirens in the us also have the strange sounding siren that almost sounds like a bubble or being underwater? | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/6c15gi/eli5_why_do_emergency_vehicles_sirens_in_the_us/ | {
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"text": [
"The thumper? \nIt is a really low tone that deaf people can feel approaching.\n",
"Sometimes the operator might toggle the power so it whoops in a different sequence, is that what you're talking about?\n\n",
"Cop here:\n\nAre you talking about the \"[piercer](_URL_0_)\" siren? \n\nIt is easier for people to identify where it's coming from.\n\nMost of our cars don't have it, but I'd generally use it when approaching an intersection."
]
} | []
| []
| [
[],
[],
[
"https://youtu.be/mlRFXSEx870"
]
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|
||
4ue2bg | why are so many olympic hosts underprepared? | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/4ue2bg/eli5_why_are_so_many_olympic_hosts_underprepared/ | {
"a_id": [
"d5oxzef",
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"text": [
"The increasing demands by IOC, that requires it to be \"even better than last time\". \n\nAny country that's smart would just shun hosting. It's not worth the economic drain for what will eventually become a ghost facility. \n\nLondon went fine, primarily because the infrastructure already existed. \n\nSochi(ghost town, never fully prepared), China(trampled Chinese on civil rights), and now Brazil(rio is a cesspool, beautiful, but literally full of drugs, shit, crime and disease) is primed to be another joke in the history of stupid decisions. ",
"Part of it comes down to the IOCs flawed selection process. A city with a strong bid who can actually afford to host a games is often passed up in exchange for a city in a country or continent that hasn't hosted in a while or for the city that bribes the officials the most.\n\nNobody wanted the 2022 Winter Olympics for example. The IOC was left with a choice between Beijing and Almaty, Kazahkstan. Like /u/soulsoda said, a lot of more developed cities decided that they didn't want to spend billions of dollars on a two week long sports party. The IOC went with Beijing since they have some existing facilities and much more money to spend."
]
} | []
| []
| [
[],
[]
]
|
||
37sdql | when i'm grilling, baking, or otherwise using aluminum foil for cooking, when do i use the matte side and when do i use the shiny side? | explainlikeimfive | http://www.reddit.com/r/explainlikeimfive/comments/37sdql/eli5_when_im_grilling_baking_or_otherwise_using/ | {
"a_id": [
"crpfz7d"
],
"score": [
3
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"text": [
"It doesn't matter. The matte/shiny sides are an artifact of the production process; there's no effect on its properties when being used for cooking, regardless of which side is out or in.\n"
]
} | []
| []
| [
[]
]
|
||
15owu5 | why are the fiscal cliff deal now focused on the senate and not the house? | For several months, the fiscal cliff deal hinged upon negotiations between Obama and Boehner. Now, the focus centers on the Senate. Why? | explainlikeimfive | http://www.reddit.com/r/explainlikeimfive/comments/15owu5/eli5_why_are_the_fiscal_cliff_deal_now_focused_on/ | {
"a_id": [
"c7og7pq",
"c7ogj4i"
],
"score": [
2,
7
],
"text": [
"Because the house could not come to a consensus and has given up. Now the senate has to generate the bill.",
"The house has a large GOP majority consisting of many congressmen who promised on record never to raise taxes under any circumstances. Even if Boehner could have made a deal, it is unlikely his own party would have supported him.\n\nSo now the best strategy appears to be to reach a deal in the Senate, and hope the House will go along with it...which is a long shot.\n\nAlso, both parties have a political interesting in giving the appearance they are trying to negotiate, so they can try to avoid blame when no deal is reached. So much of what is going on in the Senate could very well be politicians just going through the motions."
]
} | []
| []
| [
[],
[]
]
|
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