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3y3dbd | how do ancient cities end up underneath modern day cities? | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/3y3dbd/eli5_how_do_ancient_cities_end_up_underneath/ | {
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"Because the ancient cities are typically built in good places to have a city. Rivers, plains, whatever makes the original site good stays good. So when a city is destroyed, they typically rebuild in the same place.\n\nCities are \"built up\" typically in three ways:\n\n1) Catastrophe. When a big earthquake, fire, war, etc. destroy a large portion of the city, the old buildings are often torn the rest of the way down, the site leveled and new building begins. \n\n2) Gradual replacement. Buildings, city blocks, even whole neighborhoods can be leveled and rebuilt. Besides, who doesn't want a house or pyramid a few feet taller than the neighbors? #swag.\n\n3) Subsidence. Venice is a good model, but so is Mexico City. Sometimes the city literally sinks and new stories just keep getting added onto the top level. Sometimes it's sand, not water. \n\n\nIt seems like this would never be enough, but it takes time. Time like archaeologists work in. If a city is 1000 years old (positively modern.) and has a major calamity only once per generation (quiet times in the ancient world), that's 50 layers. Even if the resulting rubble pile each time is only 3 feet thick, that's a 150 foot high pile!\n",
"They don't 'end up there'. New cities and buildings are built on top of old ones. Edinburgh is a good example of this",
"I found a brick path in my backyard that was buried about 5\" down below the grass. The house was built in the 50's so all that covered the bricks was the decomposed plant matter from dead leaves, and cut grass that turned back into soil. That material gets generated by plants through photosynthesis and converting co2 from the air and water and minerals from the soil into plant matter. Plus the bricks probably sunk into the soil over time as well.",
"I think this question needs some elaboration: how is it physically possible for a city level to rise over an old city? What is the support structure? The cities I'm thinking of often have old \"underground\" cities. Shouldn't the new city have the same street level? What is supporting the new street level, that is higher, did the just fill it in?",
"You should watch that old history channel show cities of the underworld with don wildman. it's awesome, he goes around exploring all these places underground and explains how they were built, forgotten about, built on top of, then re-discovered. (or just goes crawling around in old abandonded bunkers and tunnels and whatnot and explains the history behind them)",
"Someone interested in this topic may be interested in [seeing Roman Serdica](_URL_2_) uncovered circa 2010 when a new subway station was being constructed in Sofia Bulgaria.\n\n[Another story about ruins underneath the Hotel Balkan](_URL_0_). And the Arena di Serdica hotel has a [Roman ampitheater](_URL_1_) as its atrium, with visitors/guests able to look at it from the lobby and go down to ground level to walk through it.\n\nOthers have presumably provided the obvious answers to how they were buried. When they were recent history, people didn't realize they were of historical importance (think about something you would consider boring/unimportant from 50 years ago or so) and just the accumulation of debris and so on had covered them by the time anyone would have cared.",
"1 ) In cities, the ground level is mostly increased by material carried in and discarded. Sewage systems, refuse disposal and paved streets are a recent innovation. There would have been tonnes of horse & humans' shit dropped every day. Ashes from fires were thrown out. It was all trampled and compacted.\n\n2) Also leaf mould and plant debris.\n\n3) Earthworm activity, they drag plant material into their burrows and expel waste, causing stones to \"work their way downwards\". Charles Darwin studied the activity of worms in detail.\n\n_URL_0_"
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3iajko | why are gas prices typically the only thing we sell to the $0.009? when and why did this start? if it's only supposed to be effective marketing then why do other products not use it? | explainlikeimfive | http://www.reddit.com/r/explainlikeimfive/comments/3iajko/eli5_why_are_gas_prices_typically_the_only_thing/ | {
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"Years ago a penny was actually worth something and there were actually things called \"half cents\". \n\nA gas station selling gas at .055 compared to .060 could make a difference of a few pennies which would make a difference in overall cost. \n\nPrices have obviously changed but they kept the extra cent on there because it's purely beneficial to acquire an extra cent per gallon which equates to lots of money at even just an extra penny per gallon!\n\n",
"It started because of taxes. Back when gas only cost about 0.15/gallon the federal government decided they wanted a piece of that to build and maintain roads, so they enacted a 3/10 of a cent tax. Gas companies weren't about to eat that so they passed the cost along to customers. Since gas was only 15 cents, rounding up a whole penny would be too much and would drive customers to your competitor.\n\nEventually they noticed that people didn't round up. If you price something at 49.9 cents, people treat it like it's 49 cents, not 50. That's why damn near everything is priced like that. 2.99, 14,990, etc. So they get to pocket almost an entire cent per gallon that people don't even feel like they're paying. ",
"The main reason you can price fuel to a decimal of a penny while you can't with say bigmacs or mars bars is the way we purchase. When you buy fuel you buy a variable amount, which could be 2.5798 litres or 49.67 litres. That amount is already going to end with a stupid decimal, might as well start with one. If you try that shit with discrete items, how do you handle the person who buys one and only one item? If you round up, the customer has a fair claim you are ripping them off. If you round down, you lose out. ",
"So the first part of the question has been answered pretty well, but I'm still wondering a) Why are they still allowed to do it when we don't have fractions of cents, and b) Why don't any other products do it?"
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40j4df | how does soundcloud earn revenue? | I've started using their app for music discovery and noticed that there were no ads. I've heard that it charges artists for using its services or something of the sort but how far would this be sustainable? | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/40j4df/eli5_how_does_soundcloud_earn_revenue/ | {
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"I feel this is a proper answer, as someone who used to actively use soundcloud. 1. For top musicians, dj's and mixers - most of what they post is for promotional purposes. By other musicians, followers, and promoters sharing their content it can reach a vast number of users. Strictly promotional.\n2. Aspiring musicians such as myself enjoy hearing less mainstream music too, if it truly is music, I'd love to discover it. Sharing your own content is extremely useful to recieve feedback and gain followers.\n\nFinally, Soundcloud itself 1. may be owned by a larger company, who just wants to provide the service for the love of music. 2. Makes significant revenue from larger artists contributing. 3. May be planning to implement ad's in the future, as they are still in the growth part of the business cycle. (If you use Instagram - this concept would make perfect sense to you). \nI'm not sure about which of these is the most correct, because I could not find the info available, but these are the most likely reasons.",
"According to an article I read recently, they don't have a current revenue stream to rely on.\n\n_URL_0_\n\nYou see this often enough with tech startups. They aim to build a great service that attracts a user base, then enter into trying to monetise that user base.\n\ntl;dr Soundcloud are currently borrowing money to cover their debts, as they work on/test ways to generate revenue from their service."
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76ctwu | how do all boys/girls schools turn co-ed? what reasons would a school have for doing this? | How do they find students when they turn co-ed? | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/76ctwu/eli5_how_do_all_boysgirls_schools_turn_coed_what/ | {
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"Often they do this because of a complaint. For example a girl believes she'd get a better education at school X, but school X only accepts boys, so she complains saying \"my sex should not prevent my taking classes in any way.\"",
"My Boys School turned co-ed just before I graduated. There was a \"sister school\" in town, a Girls School run by a related organization. There were many in town who were upset by this \"separate but equal\" construction, given its similarity to racial segregation.\n\nAs an experiment, a faculty-member's daughter was allowed to transfer and take classes with the boys. She had a very difficult time, because we were merciless High School boys. Merging the schools was discussed, but parents of the GS students liked the collegial atmosphere of not having boys around at school.\n\nIn the end, BS admission was opened to girls. Some transferred from the GS, but most came out of the regular public school system. Mostly the change was made by bringing in equal numbers of boys and girls in the first grade. By the time those first girl lifers graduated, the school was well integrated."
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2akazl | are the sound effects for nature documentaries from bbc or national geographic recorded live or added in later? | I have been watching quite a few of them lately, and a lot of times it seems incredible that they can get a sound recording of what they are showing, for instance when they are filming from a distance, showing tiny critters or showing things in slow motion.
What is the process of recording / editing sound for these series? | explainlikeimfive | http://www.reddit.com/r/explainlikeimfive/comments/2akazl/eli5_are_the_sound_effects_for_nature/ | {
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"They are almost always added in later, and are very rarely accurate. It's incredibly hard to record sound in the environments and conditions they are required to shoot in, out in the wild. It would be insane to ask them to record the sound of a lion licking its cub from 500 yards away in the rain.\n\nSo, they shoot the video then come back and have a foley artist make sense of the audio, and balance the need for entertainment with their duty to documentary realism."
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kpk2w | how does dying from exhaustion work, wouldn't you just pass out before you die? | How does one actually die from exhaustion, I thought that if you're beyond tired that eventually you would just pass out, thus beginning to rest, how is it fatal? | explainlikeimfive | http://www.reddit.com/r/explainlikeimfive/comments/kpk2w/eli5_how_does_dying_from_exhaustion_work_wouldnt/ | {
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"You don't die from just running out of energy - you're not a car running out of petrol. It's a combination of things like dehydration, overheating( of hypothermia if it's super cold), heart attack etc.\n\nit's is likely you would pass out before dying, but you can only rest so much without eating or drinking and if you are really really exauhsted you might just never get up and die of exposure.",
"You don't die from just running out of energy - you're not a car running out of petrol. It's a combination of things like dehydration, overheating( of hypothermia if it's super cold), heart attack etc.\n\nit's is likely you would pass out before dying, but you can only rest so much without eating or drinking and if you are really really exauhsted you might just never get up and die of exposure."
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34hl16 | the tesla home battery holds 10kwh the average home uses 30 a day how is this low amount useful? | the tesla home batteries store 10kwh the average home uses 30kwh a day (_URL_0_) so how is such a small amount useful? | explainlikeimfive | http://www.reddit.com/r/explainlikeimfive/comments/34hl16/eli5_the_tesla_home_battery_holds_10kwh_the/ | {
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"Because power plants to generate electricity are always on and can scale their output only so much the price of that electric may vary drastically depending on time of day.\n\nEspecially in summer with areas that have heavy aircon use- during the hottest part of the day rates would peak to their highest. If you could buy electric during the cheap hours you wouldn't pay those higher rates.",
"Presumably you are pairing the battery with solar panels. So you can use the power directly from the solar panels during the day, and the battery only need to hold enough power for the night. Or to even out bursts of energy usage which would go over the capacity of the solar panels.",
"Also, you can \"stack\" the batteries as many as 10 together. A single 10kWh battery might be good for some people when they can't actively get energy from their solar panels, for instance."
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3cwkhw | what does dank meme mean? | explainlikeimfive | http://www.reddit.com/r/explainlikeimfive/comments/3cwkhw/eli5what_does_dank_meme_mean/ | {
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"There is a great invention, called Urban Dictionary which [has a definition](_URL_0_)"
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3m7tn1 | what will volkswagen's fix be for their emissions cheat? won't a software fix reveal a hardware problem? | In other words, once the software is corrected, won't these cars be unable to pass emissions tests and therefore need another correction (a new exhaust system, or perhaps more)? If the correction slows the cars' performance, will the consumer be entitled to a refund because they've been lied to? | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/3m7tn1/eli5_what_will_volkswagens_fix_be_for_their/ | {
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"If the software can make the cars pass emissions tests during the test, it can make the cars pass emissions tests on the road. It will just come at a cost to fuel efficiency and power. And yes, there's going to be lawsuits over that and VW will probably have to offer some sort of refund.",
"When the software thought the cop was watching, it drove slow and clean. When it thought no cop was watching, it drove fast and dirty. The hardware was the same in both scenarios.\n\nIt's supposed to drive slow and clean all the time."
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2yonxg | how it is possible that before 2. world war only men worked and still earned enough for whole family when today we have whole families (mom, dad, child) working and barely survive? | I asume that then capitalists were paying their workers fair (and actually care for them) instead of minimum required and rather buying 5 rolls royces, couple of yachts and jets like today? Speaking for the majority then and now. Can be? | explainlikeimfive | http://www.reddit.com/r/explainlikeimfive/comments/2yonxg/eli5_how_it_is_possible_that_before_2_world_war/ | {
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"Costs of living have gone up.\n\nInflation has gone up.\n\nA culture of greed over support has evolved.\n\nPeople are too busy with their heads stuck on their phones and computer screens to notice.",
"The biggest single factor, I think, is that the price of accommodation has gone up.\n\nWhy has the price of accommodation gone up? I'd argue that a large part of it is because so many more women work, and double-income families are much more common. Therefore, house prices have risen to match the available incomes of house-buyers.",
"I think our current perception of women in the workforce is a little off. Going back to the mid 19th century, the industrial revolution created many jobs for women. The textile factories in particular employed large numbers of women and children. Child labor was also very common then.",
"In the US, housing (in good neighborhoods, in other words with good schools) is relatively limited (else the neighborhood slowly stops being good). So higher incomes across the board simply raise the price everyone pays for housing with little change in standard of living. \n\nBasically, all households increasing income by 75% doesn't change the fact that only half the students in the nation can go to top 50% schools (it just means that the price of houses in the top 50% school districts goes up with incomes). ",
"What we consider a decent living now and in 1940 are very different. One person working a normal factory job making 40k a year can easily support a 1940 lifestyle. You'd have one car, mom would cook all meals from scratch and you might have a single 13 inch black and white tv. The kids would share bedrooms and walk everwhere. When pants got torn mom would patch them. ",
"People have touched on the rise of housing costs, but it's more complicated than existing house prices going up because of increased incomes. Housing prices have also gone up because of the increasing complexity of houses. \n\nAlso, if you think that capitalists weren't gouging the worker AND the people, you need to take a better look at history. Mountains of legislation and regulating bodies were formed around that time to combat the horrific things that companies were doing. Thalidomide, radioactive cosmetics, the era is absolutely rife with people making huge profit over terrifying products. ",
"People don't realize that our \"quality of life\" is significantly better than during that era.\n\nEven 20 years ago, we didn't pay for cell phone, internet, cable. Cut that out? That's $200 a month minimum.\n\nEven 20-30 years ago, a lot of people had 1 or 2 pairs of shoes. 2 sets of clothes (daily clothes, church clothes). When you grew out of them, your younger sibling or relative go the clothes. Hell naw did you throw them away or give them to good will.\n\nEverybody has a computer, tablet, electronics and gets new ones every couple of years. If you lived in a modest apartment, had 3 sets of clothes, no electronics, made your own food - your cost of living would decrease probably by 1/2.\n\nDespite people complaining about the inequalities of the rich and the middle/poor, life in a 1st world country is much better. ",
"to say that 'only men worked' before World War II is inaccurate. women have always worked. Mortality rates were really high and the chance a single parent would end up supporting the family were also high so often a woman would be the head of household and have to work at something. Not to mention women who never married. Many of those women barely made ends meet if at all. Many women ran farms, or worked as sales clerks or teachers. Their pay was terrible, much less than a man in the same job. You might want to check your assumptions about women and work before the 1940s.",
"OP, what do you think was a decent standard of living back then? Was it the same as today? What do you mean by \"barely survive\"?\n\nStagnant wages and inflation are real things, but way more significant is the type of lifestyle we want to live now. If you wanted to, you could live a very comfortable pre-WWII existence on one income today. But darning socks, cooking at home, and going without the Internet aren't everyone's idea of a good time anymore. Hell, we throw away old laptops to buy the shiny new one; there are kids in literal poverty that have Playstations; middle class folks feel behind if their kids don't each have a bedroom to themselves. I generalize, of course, but we're living in a time of unprecedented riches. I would be careful about the replies here that want to make you a victim.\n\n[Here's a good perspective](_URL_0_) on this.\n\n > Even growing up in the 1950s, in a comfortably middle-class home, my mother's wardrobe consisted of a week's worth of school clothes, a church dress and a couple of play outfits. Her counterparts today can barely fit all their clothes in their closets, even though today's houses are much bigger than they used to be; putting a family of five in a 900-square-foot house with a single bathroom was an aspirational goal for the generation that settled Levittown, but in an era when new homes average more than 2,500 square feet, it sounds like poverty.",
"A lot of people are discussing the fact that our idea of \"quality of life\" has changed but this is an incomplete answer. True, we generally have more stuff (cell phones, TV's, internet access etc) but mass production and globalization offset a lot of these costs and in theory, should have given us a far better quality of life for even cheaper than what it was at the time.\n\nThe fact is, middle class wages have not kept up with inflation and economic growth over the last 50 years. The cost of living goes up but unfortunately, average middle class pay has not. Lots of complicated economic factors here. \n\nFormer labor secretary Robert Reich did a great expose on this issue in a documentary: \"Inequality for All\". Breaks down everything in a easy to digest way, even for non econ majors.",
"A lot of answers here and it is a complex question. Let me point to two major factors, 1.Unions had more power. 2. More products were manufactured in the US by US workers paid union negotiated decent wages. Also, you may want to note that it wasn't until after 1970 that two incomes were needed for the same standard of living. 30 years longer than you assumed. ",
"Immediately before WWII was the Great Depression, where there were plenty of families that couldn't be supported by one male householder, because too often he was out of work or the farm failed or what have you. It was the immediate postwar world--for the US at least--where hungry export markets and pent-up demand from the war and Depression years started an immense economic boom, and where women were pressured *back* into the home from their war-era factory jobs, that the household with one male wage-earner became normative for the rising middle (not working!) class. Salaries continued to rise in real terms (i.e. adjusted for inflation) throughout the 1950s and 1960s, and started to slow in the 1970s--and have pretty much stagnated in the years since. To make up for the lack of rise in salaries in real terms, and also due to higher education of women and the feminist movement, women started entering the workforce in higher numbers starting in the 1970s. \n\nEdited to add: it is also true that even poorer folk nowadays have more luxuries than were available in the postwar era, but these costs are trivial compared to the real salary-eaters--housing and transportation, which costs have not stagnated although real earnings have.",
"Everything actually started going south around the 1960s.\n\nWhen you account for inflation, American workers have not had a raise since about the 70s. Minimum wage has actually fallen. Meanwhile executive pay, which is normally given as a ratio of worker:executive compensation (which makes it independent of inflation) has gone from about 1:30 in the 1960s to around 1:390 today. Where does all that extra money come from? Yup: from the money that used to go to worker's wages.\n\nAs a result, the middle class is getting squeezed out of existence, people who should be comfortably well-off are a couple of paychecks from being homeless. In families where one person could comfortably support the household, more people have to work. And the gulf between rich and poor is at an obscene, historical high.\n\nBut hey, don't worry that one good illness could bankrupt you (some 60% of personal bankruptcies are due to medical bills), rejoice instead that you have \"more stuff\" than your primitive predecessors in the stone age of 1960. This argument, propounded by such eminent economists as Bill O'Reilley, says that it doesn't MATTER how close to bankruptcy you are, or how many hours the whole family has to work to keep the household afloat, You own an actual, freaking refrigerator, a treasure far beyond gold to the poor primitive sods of 50 years ago. You're not one of those starving, distended-belly kids in Africa lying in the dirt with vultures standing nearby. Ergo, you are not actually poor. QED.\n\nReal economists, not the fake ones on Faux News, call this argument \"a load of dingo's kidneys.\" It is neither factually correct (actually most poor people don't *own* refrigerators, they pay rent on them as part of the dingy, run-down apartment they rent. I'm actually fairly well-off, and *I* don't own a refrigerator, it's part of the rent I pay.), nor meaningful in any real economic analysis.\n\n",
"Simply put, wage stagnation.\n\nThis means that while the price of pretty much everything has gone up over the last thirty years, wages haven't kept up. \n\nThis is due to businesses being cheap as hell and taking advantage of economically hard times to keep their workers happy with horrible wages as opposed to being completely unemployed."
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3r2i80 | why dont all planes have an aircraft recovery system thats built to only track airplane locations 24/7 | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/3r2i80/eli5_why_dont_all_planes_have_an_aircraft/ | {
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"You might have to expand on what you mean by your tracking system. \n\nAll aircraft in controlled airspace are tracked from the ground by air traffic control. Plus all commercial airliners, at the very least, contain a tracking device onboard, which revords things like position, bearing and even the cockpit conversations. On the event of a crash this device saves the conversation for the a while before the crash and the aircraft's position, control position and so on. \n\nIs this what you mean? "
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9c0nxt | why do ocean waves get more rough during a storm? | What causes it? | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/9c0nxt/eli5_why_do_ocean_waves_get_more_rough_during_a/ | {
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"The answer is **wind**. My one word answer got removed, presumably for being one word. Therefore, I layout a slightly more wordy response here, in which the answer is wind, specifically increased levels of it during a storm. The increased levels of wind during a storm exert wind shear on the water surface which whips up the water into waves. During storms, the wind direction is not particularly consistent, it is more chaotic and so the waves may come in all directions. This means that whichever way your vessel is facing, it is likely to get tossed about (particularly if it's a small vessel). In strong storms, there is even a phenomenon known as [rogue waves](_URL_0_), in which the wave height is extrmely large and seemingly comes from nowhere. \n\n"
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6msybx | why does coffee taste so much better after eating something sweet? | I have two coffees each day at work. The first tends to be early in the morning, the second mid-morning after fresh pastries have been delivered to the office. The second coffee tastes so much better than the first after I've had a few bites of something sweet, particularly a sweet food with carbs (e.g. almond croissant). Why is that? What is the relationship between sweet and bitter taste buds? | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/6msybx/eli5_why_does_coffee_taste_so_much_better_after/ | {
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"It's called Sensory fatigue.\nOnce your brain becomes accustomed to a constant signal, it tends to ignore it, and focuses on looking for major changes. So, if you're brain is constantly tasting sweet, sweet things become the norm, and your brain doesn't notice them much. However, do something drastic like eating a pickle, and your brain will signal that as \"extremely extra sour\" due to the sudden change.Your brain returns to \"normal\" after you let your senses rest a bit."
]
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| []
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[]
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2idgke | how can artists legally sell paintings/sculptures of licensed characters? | I've been to a couple of conventions this year with my boyfriend and he kept pointing out how he's surprised vendors haven't been fined for their merchandise. An example would be, people printing out images from books, movies, tv shows and pasting them on to bottle caps or light switch covers and reselling them. Or people painting/drawing/sculpting characters and selling them. I was also curious of people buying fabric with actors and characters printed on them, sewing items, then selling them? I would think they'd get trouble for this right? I'm not talking about Disney, more like Doctor Who, Sam and Dean, Beetlejuice, Jason, Freddy, etc. Those are what I saw a lot of. | explainlikeimfive | http://www.reddit.com/r/explainlikeimfive/comments/2idgke/eli5_how_can_artists_legally_sell/ | {
"a_id": [
"cl15nsd",
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"text": [
"No, that's not legal. If they get caught, they're getting a cease-and-desist letter from the copyright holder. ",
"They're too small for the rights holders to give a shit, that's all. If they were making $100 million annually from illegally using others' intellectual property, you can bet they'd be sued for it."
]
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[],
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cntnuz | why do clouds move slowly in one direction, and not sporadically in different directions like, let’s say, a plastic bag would fly around in the wind? | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/cntnuz/eli5_why_do_clouds_move_slowly_in_one_direction/ | {
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"There are different kind of air flow in the earth, close to the ground there are some produced for the heat and cold of the temperature in a minor scale, in the upper side, the air flow depends of it but in a larger scale, considering the sea current, temperature of a larger portion of ground, etc. This is what causes the clouds to follow a more stable pattern, and the turbulence you felt in the airplanes... I hope I get it right.",
"The air near the ground is much more turbulent than air at higher altitudes. Near the ground the wind is mixed up by all of the stuff, like trees and mountains and humidity and whatever. \n\nThere isn't anything higher up so what turbulence does arise is quickly averaged and smoothed so that the wind moves as a very steady bulk. (If you've seen fountains with laminar flow, it's the same kind of difference.)\n\nLayers form with winds moving in different directions. Some turbulence does form at the interfaces, but in general the cloud and the air it's in are moving at the same speed and in the same direction, so the cloud doesn't \"feel\" any wind. Same as you don't feel any wind inside your car (assuming windows are up lol).",
"Basically, scale. Clouds are huge. The smallest of them are larger than a city block. If you look at them close up, parts of the cloud do move sporadically in the local breezes, but looking at the cloud as a whole, it is only going to move with the general flow of the wind."
]
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[],
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||
4w8xo3 | would snow put out a fire faster or slower than rain? | Or maybe heavy snow vs heavy rain? | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/4w8xo3/eli5_would_snow_put_out_a_fire_faster_or_slower/ | {
"a_id": [
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"score": [
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"text": [
"Generally much slower if you are asking about a typical snowfall or rain storm. The general ratio at 30* F is 1\" of rainfall = 10\" of snow. So it would need to snow* ^^^^fucking ^^^^autocorrect for a much longer period to equal the same amount of rain that falls in many places.\n\nThe reason for this is that in winter the air is typically much dryer and doesn't hold as much moisture before snow starts. In the summer with the humidity, the air and clouds are much more moisture dense and that's how you get such heavy rainfall in many places exceeding several inches an hour. "
]
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| []
| [
[]
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|
|
6um6di | how does apple know whether or not a charging cable is "certified"? | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/6um6di/eli5_how_does_apple_know_whether_or_not_a/ | {
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"text": [
"There s a chip inside the lightning cable that tells the phone that its a legitimate chip approved by apple, if the phone doesn't see this, then its not legit. Yes it can be hacked, thats how some knockoff cables from China were introduced."
]
} | []
| []
| [
[]
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|
||
9etmxl | where does stuff go when it gets in your eyeball? is the fluid in your eyes somewhat acidic and dissolve it? | Something gets in your eye and it's there for a few seconds or few minutes. Then it's gone. | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/9etmxl/eli5_where_does_stuff_go_when_it_gets_in_your/ | {
"a_id": [
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"text": [
"The fluid in your eye -- > I sincerely hope you mean tears and not the vitreous gel.\n\nTears will flush the \"stuff\" away from your eyeball. A lot better than dissolving it.",
"No dissolving, just washes away. When you blink your eye actually closes from your temple to your nose too, not all at once, so this helps push stuff out of your eye as well. That’s why you always get those crustys by your nose, not your temple. ",
"I had a big fly into my eye and it got caught under my eyelid and I didn’t notice? When I did finally remove said bug it was covered on a white goop but still fully intact. "
]
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[],
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frgqfr | why to light bulbs burn out after a few months but computer/tv screens last for many years? | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/frgqfr/eli5_why_to_light_bulbs_burn_out_after_a_few/ | {
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"You might be thinking of incandescent light bulbs. They work by heating up a filament to be so hot that it glows very brightly. It would corrode very quickly in air at that temperature, but they put a near-vacuum or inert gas in the bulb that lets it glow for a lot longer before it disintegrates.\n\nScreens have never been incandescent. The older style was cathode ray tube (CRT) which is most similar to a fluorescent bulb. A stream of electrons is shot from the back to a sensitive plate at the front that glows when hit. Modern ones are most commonly liquid crystal display (LCD) or other technology that's a bit more sophisticated as well than \"heat something up really really hot.\" So they don't suffer the same limited lifespan. You can get light-emitting diode (LED) bulbs nowadays that similarly last a very long time and are really cheap to run.\n\n*That said, apparently it is possible to have incandescent bulbs last a looooong time, but there was a business agreement way back in the day to give them a reduced lifespan. This way they could sell a lot more bulbs rather than have people only buy them when they get violently broken.",
"Light bulbs (the kind that you're thinking of) require a heated filament that literally glows because it's so hot. This causes physical damage to the material over time and eventually it breaks. It quite literally burns out.\n\nModern TV and computer screens emit light through an LED (light emitting diode (electricity only can go one way through a diode, that super important here)), which does not require extreme heat to give off light. LEDs can still stop emitting light, but they technically aren't \"burning out\", it's other things that are going wrong. So it is possible for TVs and computers to get bad pixels.\n\nPretty much all light bulbs made and sold today also use LEDs. Going forward in your life, light bulbs \"burning out\" will be *way* less of an issue than it used to be just a few years ago. They can be made any color and brightness so you won't know the difference between that and older style bulbs. If you have any LED light bulbs in your house, you likely have bulbs that will last longer than you will.",
"Light bulbs don't burn out in a few months, at least not anymore. Old-style incandescent bulb that heated a filament to yellow hot burned out, but modern LED bulbs use the same technology as computer screens and can last just as long.\n\nAlso, when a LED element on a screen fails, you get a tiny black dot, sometimes so small you don't even notice. When a light bulb fails, the whole thing fails."
]
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1fvw40 | why are school buses out and about at the most random times of the day? | I understand when they're taking kids to and from school and field trips but I see them with no kids just driving around. | explainlikeimfive | http://www.reddit.com/r/explainlikeimfive/comments/1fvw40/eli5_why_are_school_buses_out_and_about_at_the/ | {
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"text": [
"They can also be chartered by other organizations, and when they are done dropping off kids (at school, at a field trip etc...) they need to be parked somewhere - the drivers don't take their schoolbus home with them ;)",
"Not every school bus is owned by a school corporation. There are companies that lease out buses to schools, just like a lunch program. So they can be going to other places that hire them, like a church group.\n\nAlso, some buses are owner-operator situations, like semis. It's not common, but it is still practiced. I don't know how it works though, when it comes to maintenance costs. Probably tax deductible. \n\nThat brings up that not all schools can afford to maintain their own fleet. Sometimes they'll have to have a repair shop fix them, so they'll drive them there. \n\nThey aren't restricted to just specific times of the day for use or just child transportation. ",
"In my town the bus company does two different sets of routes: the private/church schools go earlier in the morning and then the public schools go later.\n\nSo the busses run around picking up the private kids, drop them off, then they drive (empty) to start the public routes. Then after dropoff and after lunch/field trips they are heading back (empty) to the private schools to pick up kids and then repeat with the public. There's a good amount of time these busses are empty somehow.\n\nAlso, you're noticing empty busses because you're looking for them.",
"In addition to what others have said - here are a couple of more - Buses have to be staged for pickups so they may be on the road 30+ minutes prior to end of school. \n\nIf there is a school outing often there is no place to park the bus whilst the kids are at the event. In those cases the bus will go to a store parking lot or some place with a large parking lot where they can park and wait.\n\nSometimes during they day they are out on test runs after a mechanic back at the bus barns has made some change to the bus.\n"
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2m6xic | if monster hdmi cables are such a ripoff, why do they have such good reviews on best buy's site? | explainlikeimfive | http://www.reddit.com/r/explainlikeimfive/comments/2m6xic/eli5if_monster_hdmi_cables_are_such_a_ripoff_why/ | {
"a_id": [
"cm1ggfa"
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"score": [
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"text": [
"Confirmation bias. You should read audiophile magazines if you want to see unprecedented levels of bullshit pseudoscience and handwaving.\n\n_URL_0_\n\nHere's a good one: These guys are selling, essentially, a brick. You put it *near* your audio equipment, not too close or too far away, and at just the right angle, and it makes it sound better, **because it's black**:\n\n_URL_1_\n\n > The Blackbody is unlike any other filter or conditioner. All power filters and conditioners address noise found on wires, but there’s another type of noise altogether. Until now, this inconspicuous type of noise has been largely unacknowledged. It is caused by constant electromagnetic interaction between gear and immediately surrounding objects: stands, racks, nearby signal wiring, enclosures, and other objects containing circuitry or not. This type of radiated noise is not confined to wires. The Blackbody works by absorbing these reflections, effectively solving the problem. Being the only conditioner of its kind, it offers a level of performance previously unattainable. "
]
} | []
| []
| [
[
"http://consumerist.com/2008/03/03/do-coat-hangers-sound-as-good-monster-cables/",
"http://www.lessloss.com/blackbody-p-200.html"
]
]
|
||
5riqim | do people in cults consider themselves to be in a cult? | "Cult" has an extremely negative connotation to the general public so I'm wondering if people who are in cults consider it as such. | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/5riqim/eli5_do_people_in_cults_consider_themselves_to_be/ | {
"a_id": [
"dd7kljk",
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"text": [
"You'd have to ask a cultist to get an exact answer. Generally though people who left cults say that at the time they did not consider anything wrong with it. It was a more a group, organization or family, but not a \"cult\". ",
"Of course not. Cults are full of crazy people who believe idiotic things. They just happened to find the enlightened people who got all of it right."
]
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[],
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4j0d6y | why is the unit of distance light 'year'? | My noobie self needs a reminder every time I read 'n light years' that it's a unit of distance, not time. | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/4j0d6y/eli5_why_is_the_unit_of_distance_light_year/ | {
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"text": [
"Light travels at a finite, but very fast, speed. That speed is a constant in space, 299,792,458 meters every second. So after a second, light has traveled a specific distance. After a week, light has traveled a specific distance. After a year, light has traveled a specific distance. So light travels a very specific distance after a year, and that distance (Because light is very fast) is quite a long distance. Space is very big, so 'very big measurements' are useful.\n\nSo, a light year is useful in that it is a consistent distance and big enough to be a practical measurement for distances in space. \n\nIf it helps, think of it as \"The distance light travels in a year\" instead of just \"Light year\"",
"In addition to what others have said, all distances could be expressed as a measure of time if you assume a constant speed. So, if your highway speed is 70 miles per hour, you could say that a town 70 miles away is 1 highway hour away. We do not need to do so because miles (or kilometers) are intuitive to us, since we experience them often. \n\nThe problem with expressing astronomical distances in measures of distance that we have an intuitive sense of on earth is that the numbers would quickly grow unwieldy. Use of light years helps get around that problem, and can help us develop an intuition for the distances described. (Consider that the sun is 8.3 light *minutes* away!)\n\nEdit: Revised last sentence of first paragraph for clarity."
]
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63hxcs | when metalsmith's make swords, when we did we begin to fully understand what was happening with the metal from a scientific perspective? | Hey all,
I watch a lot of videos on how to make swords and knives. Many of these videos explain what is happening to the metal as they shape it in to a blade.
But, when did we begin to fully understand what was happening with the metal at a molecular level? For instance, there are some videos that say that folding the metal allows for carbon to be diffused in the metal. When did we learn that this was happening? | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/63hxcs/eli5_when_metalsmiths_make_swords_when_we_did_we/ | {
"a_id": [
"dfu9dtk"
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"text": [
"For a long time, metallurgy was a refined trade that was held by master craftsmen, who did not trust their knowledge to anyone except their apprentices, because if 'just anyone' knew what they knew, the local smith might quickly be out of a job. With the invention of chemical sciences, people began to understand that metallurgy was basically just like any other practical craft of mixing ingredients together and making shapes out of them, like baking and pottery. The temperatures and forces involved were just larger. *De re metallica* by Gregorius Agricola was probably the first dedicated text about metallurgical sciences and ores in modern history, published in 1556.\n\nThe exact compounds that were historically important in blade-making are compounds around iron and steel (iron-carbon mixtures): ferrite, martensite, pearlite and cementite. Knowledge, experience and understanding of these compounds expanded rapidly with the invention of the Blast Furnace, around the beginning of the 16th century in France."
]
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347g1r | why are there so few boy names compared to girl names? | I've been thinking about how many more options there seem to be when naming girls as opposed to boys. I realize that there are popular names that dominate for both sexes, but there seem to be a dozen or so male names that make up like 70% of the men I know. Can anyone shed some light on this? | explainlikeimfive | http://www.reddit.com/r/explainlikeimfive/comments/347g1r/eli5_why_are_there_so_few_boy_names_compared_to/ | {
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"Men as whole are grown and brought up more conservatively. A lot of flair isn't viewed as being cute or a plus for men. Be it names, styles, the way they act or show emotions... et cetera.\n\nIt is socially more acceptable for girls to display themselves in unique ways.",
"I think the main reasons are: \n\n1. Every male name can be made into a female name by adding -a, -ia, or similar, but there is no similar way to turn female-only names back into male names.\n\n2. \"Nature\" names are considered unacceptable for boys and somewhat acceptable for girls.\n\n3. For some reason, we tend to keep forms of female names from multiple nations/eras, but not male names. For example, Laura, Lauren, Lara, Laurie, but only one Lawrence: Julia, Julie, Juliet, Julietta, but only one Julian: Marie, Mary, Maria, Maryam, Miriam, Mariah, Molly...\n\n4. There is a fairly strong tradition in many Western countries of naming baby boys after their fathers, grandfathers, or uncles; the parallel custom of using family names for girls is much weaker and less widespread. This means that once you get a large concentration of Johns, Josephs, Michaels, Marks, and Joshuas, you end up with a big chunk of the male population already \"spoken for\", so to speak, as those names get reserved for all of the eldest sons who need to be named after a family member, and the number of sons for whom the parents can chose whatever name they want is smaller in the first place."
]
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a5tsxb | so i know that you can't eat/drink x hours before surgery to not aspirate your food, but what do they do when it's an unexpected surgery and the person just ate, like a car crash or burst appendix, etc? | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/a5tsxb/eli5_so_i_know_that_you_cant_eatdrink_x_hours/ | {
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"text": [
"They operate anyway.\n\nYou fast and go on the toilet before surgery to make it safer, it is not like they can't operate on you if you haven't fasted and gone on the toilet recently.",
"It's a risk vs reward issue. \n\n If you can be stabilized until you are clear of food in your stomach. They will often times wait. \n\nIf you cannot be stabilized and whatever you need surgery for can kill you anyway they have alternate anesthesia techniques can be used depending on the surgery. \n\nSource:work for on call ortho trauma surgeon. \n\n",
"We ask that you fast to not have any contents in your stomach. Newer research is amending this practice, but listen to what they ask of you if you need surgery. In anesthesia if an emergency happens where we can't reasonably assume that your stomach is empty then we go ahead with the surgery. However, we modify our induction of anesthesia to a technique called a Rapid Sequence Induction (RSI). This has 3 main safety features built into it for the process. 1. We use a very fast and very short paralytic called Succinylcholine. 2. We use an endotracheal tube and apply crichoid pressure to hopefully occluded the esophagus while we intubate you. 3. We don't breathe for you while we wait for the paralytic to take effect. I can answer more as needed if you'd like. I'm an anesthesia provider. ",
"Uh, it can get kinda messy when they have a full stomach. Usually not life threatening but not something we wish on other people.\n\nI asked my doctor.",
"They accept the chance of the person dying is significantly higher, but assess the risk of death without surgery.\n\nWhere you can mitigate risk, you really should.",
"Ok I thought more about this before and started wondering - if the drugs are strong enough to cause your gastric sphincter to clock off and for your lungs to take a personal day, why doesn’t it cause your heart to stop? I know in large enough amounts it will, but if control of the lungs and oesophageal sphincter are both achieved by muscles, then how does your heart muscle not take a break too?"
]
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3yxw3i | eu and the usa are pretty equal economically. why do all usa major cities have massive skyscrapers while europe has little to none. | Here are some examples.
London: _URL_0_
New York: _URL_6_
Berlin: _URL_3_
Chicago: _URL_7_
Madrid:_URL_4_
Dallas: _URL_5_
Rome:_URL_2_
Seattle:_URL_1_ | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/3yxw3i/eli5_eu_and_the_usa_are_pretty_equal_economically/ | {
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"text": [
"Skyscrapers were built in America for 2 reasons:\n1. Land was at a premium. New York City isn't that big size-wise, and you want to get the most bang for your buck.\n\n2. Dick waving contests. I'm not saying it was a bad thing, but it's the truth. You wanted your company to have the tallest building in world. ",
"The European are generally a lot older than the US and in most cases the local government works to protect the classic skyline rather than build massive skyscrapers that block the view. If you go outside of the central older parts of town you'll start seeing bigger buildings. For example Rome, that city is thousands of years old, stick a couple of skyscrapers in that picture and you've ruined that look and the locals will kick off.\nedit:pressed save too soon.",
"In London there are planning laws limiting where very tall buildings can be built. It's to preserve the character and the view of the historic buildings that have made the character of London for hundreds of years. The best known is the Protected View of St Pauls Cathedral - one of the greatest pieces of architecture in Britain. New buildings are not allowed to obscure it.\n\n",
"The EU was not always the EU. The EU was all completely separate countries most had significantly smaller economies than the US. Also WWII did damage to many areas and economies slowing growth, while the US economy was booming after WWII with no infrastructure damage. \n\nMany of the cities in EU nations are much older than US cities and the buildings have historic significance, so they are often not cleared out to make room for newer modern buildings. \n\nHowever, there are still several skyscrapers in EU nations. You pointed out Madrid. London is a contender, Vienna, Benidorm, Paris, Frankfurt, Milan, Rotterdam, and Warsaw have taller buildings. ",
"European cities are way, way older, so they're dense in different ways. Paris has miles and miles and miles of 5-10 story buildings and as such is actually denser than pretty much every American city outside of New York. What's the need for skyscrapers if that's the case?\n\nThat said, again to go back to Paris, European suburbs typically have those buildings you consider skyscrapers- although not as tall- whereas American suburbs are typically huge swaths of single family homes. I'm referring particularly to La Defense, outside of Paris.",
"As far as Paris goes, the actual downtown area of the city can't be used for heavy construction because coal mining in the area removed so much rock from underneath that a large building like you'd see in New York might be too heavy. They actually passed a law against that sort of thing because there were a few minor cave-ins.\n\nBut most places, I'd say its the historic character of the city that prevents it.",
"I know in Greece the govt won't allow anything build that will obscure the view of the Acropolis."
]
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"https://main2seattle.files.wordpress.com/2010/12/seattle-skyline-istock.jpg",
"https://ship-stuff.com/files/images/rome.jpg",
"https://c1.staticflickr.com/9/8201/8182802843_c29dd06f9b_b.jpg",
"https://c2.staticflickr.com/6/5042/5376320082_935973ccf7_b.jpg",
"http://www.imagesfromtexas.com/images/large/Dallas-Skyline-before-Sunset-612-3.jpg",
"https://fauf.fau.edu/NetCommunity/image/alumni/New-York-City-Skyline-From-New-Jersey.jpg",
"https://upload.wikimedia.org/wikipedia/commons/2/2b/Chicago_Skyline_from_Lake_Michigan.jpg"
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28s4u2 | why does someone talking in your ear in a very loud environment (ie. concert) sound deafening? | explainlikeimfive | http://www.reddit.com/r/explainlikeimfive/comments/28s4u2/eli5_why_does_someone_talking_in_your_ear_in_a/ | {
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"text": [
"Because they are talking loudly/shouting directly into your ear, which would hurt your ears even if there was no music.",
"....you're asking why do loud sounds sound deafening?\n\nThe answer is because they're loud. And you friend is having to shout louder, closer to you so you can hear him, right next to your ear.",
"Did you know that you can (almost) always understand it when someone is whispering in your ear, as long as he is close enough to you? The next time you are in a very loud environment, go ahead and try it - and don't ruin other people's ears."
]
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4h2mz1 | why stock photos are so damn expensive, and why it's reasonable to buy them at its price | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/4h2mz1/eli5_why_stock_photos_are_so_damn_expensive_and/ | {
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"text": [
"Because it's still cheaper than hiring a film crew and an actor to film a 4 second clip of a girl diving."
]
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|
||
8cp82c | why can’t urine and semen mix together when you release? | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/8cp82c/eli5_why_cant_urine_and_semen_mix_together_when/ | {
"a_id": [
"dxgnwc9"
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"text": [
"I mean, they *can*, there's nothing in the fluids that stop them from interacting, but there's a muscle that acts as sort of natural valve that cuts off access between the bladder and urethra when ejaculation is occurring; the semen will mix with any residual urine still in the urethra if there was recent urination, but it's not a whole lot of urine. \n\nSimilarly, if you urinate after ejaculation, the urine helps to clean out your urethra of residual semen. This can help minimize chances of conception if you decide to rely on pulling out as contraception (really though, don't do this, but if you must, take a pee break between rounds.) but again, you're talking very small residual traces, not likely to be detected unless you're doing some sort of analysis."
]
} | []
| []
| [
[]
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|
||
1n1dwe | how does conditioner make hair go from a tangled mess to being able to have a comb run through it? | As the title states I'm curious how conditioner can untangle hair and make it easier to have combs run through it almost like there was no tangled mess to begin with. How do the chemicals in the conditioner do that? | explainlikeimfive | http://www.reddit.com/r/explainlikeimfive/comments/1n1dwe/eli5how_does_conditioner_make_hair_go_from_a/ | {
"a_id": [
"ccejhm1"
],
"score": [
3
],
"text": [
"The conditioner is basically oils, so it lubricates the strands allowing them to slide past each other and untangle easier."
]
} | []
| []
| [
[]
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|
|
deegcp | what causes down syndrome and the different variations of it | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/deegcp/eli5_what_causes_down_syndrome_and_the_different/ | {
"a_id": [
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"text": [
"Down syndrome can be due to a variety of things. One of the most common is what is called a meiotic non-disjunction.\n\nWhen our sex cells aka gametes divide, they undergo a process called meiosis. All eggs and sperm undergo this process so that they form a \"haploid\" cell or a cell with only 23 chromosomes. All of our body cells are \"diploid\" have 46 chromosomes, but sex cells only have half because when an egg and sperm combine that will form the perfect 46 chromosomes we all have for the most part. However, during meiosis, when the chromosomes (DNA) line up along the equator of a cell to prepare to divide, they can fail to split apart in meiosis. This is called non-disjunction and that leaves some cells with an extra chromosome. In the case of Down Syndrome, that is an extra or third chromosome 21 aka Trisomy 21.\n\nThere are also trisomy 13 (Patau syndrome) and trisomy 18 ( Edwards syndrome) which typically are fatal after birth. The reason trisomy 21 is viable is because of a concept called mosaicism which means that not all of the cells in the individual's body will have the extra chromosome 21. Some will actually lose the extra copy through a process called trisomy rescue which is due to anaphase lag. In this, the chromosomes do not attach to the spindle that pulls them apart and the extra chromosome gets lost during cell division.\n\nSource: I'm a medical student"
]
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| []
| [
[]
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|
||
cksjao | how are movies dubbed into a second language while maintaining other background audio? | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/cksjao/eli5_how_are_movies_dubbed_into_a_second_language/ | {
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"text": [
"The background audio and voice audio are separate tracks. They are laid over each other to create the illusion of a single track. For other languages, the native voice track is removed and the second language added over the background track.",
"Film dialogue is organised onto separate tracks from the sound effects and music.\nAs part of finishing a film you usually export stems of those music and effects that you can then send to studios where they add the new dialogue on top.",
"So when they shoot a scene, they have these boom mics hanging above and aiming down at the actors. This gets the diaglogue really well, but not so good at the background sounds. In fact, most of the background, ambient and incidental sounds (like footsteps, punches, machinery) is recorded seperately by Foley artists and sound designers/editors. Google videos of Foley artists at work, its fascinating. \n\nANyways - the dialogue, the foley/background/ambient sound and the music are all recorded on different tracks. They're only combined or _mixed_ together when the final sound mastering is done, just before its added to the video stream/film. And in digital projection the two are never combined per se, they're synchronized at playback time. \n\nSo to get a dubbed version, you rerecord the dialogue in a studio and combine it with the original masters of the ambient/foley tracks and music tracks. This is why there are seperate Oscar categories for Mixing, Score (music) and Sound Editing (foley and special effects creation)... you can have really cool sounds but if its not mixed well it will still suck."
]
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[],
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|
||
6c5wem | when jumping a car battery, why is it better to clamp the black clamp, intended for the dead battery, to medal instead of to the battery? and why does it still work when you do clamp it to the battery? | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/6c5wem/eli5_when_jumping_a_car_battery_why_is_it_better/ | {
"a_id": [
"dhs4mlu"
],
"score": [
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"text": [
"When you connect the 4th clamp to the dead car there's some chance there will be an arc of electricity just before the clamp closes or just after it's reopened. Since dead batteries being charged can release flammable gasses, and all the metal in the engine bay is wired to the black terminal on the battery, clamping to another bit of metal greatly reduces the chance that you'll start a fire. \n\nIt works because the black terminal of the battery is wired to the metal you're clamping it two. Perhaps it helps to imagine there's an extra jumper cable and you're clamping the black cable to that when you clamp it to a bit of metal in the engine bay. "
]
} | []
| []
| [
[]
]
|
||
3775d7 | the trees in my yard drop thousands of those helicopter seeds each year. why have i never seen new trees sprout from them? | explainlikeimfive | http://www.reddit.com/r/explainlikeimfive/comments/3775d7/eli5the_trees_in_my_yard_drop_thousands_of_those/ | {
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"text": [
"Do you mow the grass around the tree?",
"Germinating and sprouting depend on many conditions - only a few out of the thousands of seeds actually have the potential of growing into a new tree.\n\nChances are, you have one or two sprouts, but you may have accidentally mowed over them at some point.",
"The parent dominates the local area, taking light & nutrients away from the saplings which stops their growth. The seeds are designed to disperse, the parents don't want the young saplings to grow underneath them and compete for resources. ",
"Check your gutters. I usually have a few sprouting up there with the extra moisture. But it is really a spray and pray method and the actual expectation of success being very low. Squirrels eat a lot of the too. ",
"Do you mow your lawn?"
]
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[],
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||
2rahcp | what is the purpose of having academically gifted children attend university at an early age? | My university has a special program which allows students to take university classes starting from age 14. I know a 16 year old girl who is a registered university student and she is required to stay in the regular dorms with her older brother who is also a student.
I heard her mention that most of the older guys in class are nice to her but she always has to make excuses when they ask her out on dates because none of them are aware of her actual age and assume she is at least 18. When classmates invite her to the college pub she legally has to decline but doesn't want everyone to know that she is in an accelerated program. She has to wait a couple years before she can enjoy many college social events or mixers but she told me she drank at a house party before and nobody found out, so she got a taste of college life, such as going to late night parties before most of her other friends of the same age did.
This makes me think of why universities have programs for gifted students in mainstream courses. Is it always beneficial for the students to skip ahead? Is it for them to enter the job market earlier? | explainlikeimfive | http://www.reddit.com/r/explainlikeimfive/comments/2rahcp/eli5_what_is_the_purpose_of_having_academically/ | {
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"text": [
"Skipping grades and attending college courses can be one of the simplest ways for gifted children to learn material that matches their abilities.\n\nHowever, it's not without problems - mostly the social ones which you mention (_URL_0_). Probably having them attend special classes or schools with other gifted children their age would be better, but it's harder to do that.\n\nAs to the long term benefits, it's hard to say for sure, although in child prodigies grow up to be relatively normal adults.",
"It's a difficult situation with pros and cons both ways:\n\nYou want to advance gifted children because they are capable of dealing with advanced material and most schools aren't equipped to provide that material to their age group. Without challenging material their learning is held back and they can become bored and disruptive.\n\nOn the other hand there are many disadvantages, some of which you've mentioned. While gifted children may be mentally competent to deal with advanced material, they're not usually emotionally or physically (or even legally) ready to deal with an environment designed for older students. They can't deal with relationships; phys ed and sporting expectations; and being the one left out when others are drinking, smoking, driving, etc.\n\nOne solution is to find a program that provides advanced learning to younger, gifted students. Even that's not perfect; sometimes just being in a special program causes emotional and social problems, like the inability to handle the higher expectations and harassment from peers outside the program. Gifted and talented programs exist in primary and secondary schools but it's not really possible at the tertiary (university) level.",
"If you are not challenged you end up never knowing how to work hard. You end up lazy always thinking it will be fine, and unable to stick to a work schedule. Then study habits and things like working under stress are never experienced. "
]
} | []
| []
| [
[
"http://en.wikipedia.org/wiki/Grade_skipping"
],
[],
[]
]
|
|
60wj0b | why is sports gambling generally centered around point spreads instead of direct results (winners/losers)? | Edit: over/under is another basic one, but doesn't really change the question. | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/60wj0b/eli5_why_is_sports_gambling_generally_centered/ | {
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"text": [
"Because otherwise it's hard to get bets. Imagine two teams, Foo University and Bar State College. Foo has a great team, is undefeated this season. Bar State has a record of 2-7 and is never a major factor. They're playing each other.\n\nSo... sure, you can say that Foo will almost certainly win. But how to you monetize that? How do you get anyone to bet on this game? Even the most diehard Bar State alumni won't waste their money on a simple win/lose bet.\n\nSo, this is why there's a spread. If you say that there is a 20 point spread, suddenly the odds of the wager paying off are much, much closer to even for either team. Now you can take bets -- and make money,",
"The bookie's goal is to get as much money bet as possible, but also to have it bet as *evenly* as possible. So if Team A is playing Team B, the bookie wants the same amount of money bet on Team A as is bet on Team B. That way, no matter who wins, the bookie isn't giving up any of their *own* money. If $500 is bet on team A and $500 is bet on Team B, no matter who wins, there's enough money being bet to cover the payouts.\n\nThe bookie takes a cut of the money bet; if you want to bet $100, you have to pay the bookie $105. The bookie keeps $5 no matter how your bet turns out. \n\nOK, so what happens when Team A is **obviously** better than Team B? That's where the point spread comes in: the point spread represents the best estimate of 50/50 odds. The goal with the point spread is to get the same amount of money bet on Team A as is bet on Team B. ",
"The odds are better if you bet a spread.\n\nLet's imagine two teams having a hockey game, the Destroyers and the Wimps. The Destroyers are going to crush the Wimps. No one on earth thinks the Wimps are going to win.\n\nSo the bookies won't give you very good odds to bet the Destroyers. Like, if you bet the Destroyers to win, and give them $100, you'll get $101 back. There's no point, you don't win anything, and on the extremely slim chance of a Wimps upset, you're out $100.\n\nSince the bookies still want you to bet, because they make money, they say \"let's give it a spread. Destroyers have to win by 4 goals or more.\" So the line would be Destroyers (-3.5) vs Wimps\n\nThat makes things interesting. Now they can offer better odds. Everyone knows that the Destroyers are going to win, but now you have to figure out if they'll cover the spread or not. ",
"Also, a lot of British and European bookmakers do structure their bets around win/lose/draw without using any kind of point spread. They just adjust the payouts for each event to reflect the estimated odds."
]
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[],
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1w5o6l | why do hot objects weigh differently compared to room temperature objects. | My Chem lab professor said that we have to wait for things to cool to room temperature so we could get an accurate measurement. I don't understand why. | explainlikeimfive | http://www.reddit.com/r/explainlikeimfive/comments/1w5o6l/eli5why_do_hot_objects_weigh_differently_compared/ | {
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"text": [
"There's two reasons why you have to wait for a constant temperature to weigh something: one is that hot air is less dense than cold air, and can produce a buoyancy that tends to lift the object up and reduce its weight. Also, if you are heating something to dry it out, water molecules will be released from the sample, changing the weight. You want to heat something enough to remove the water, and then wait for it to cool to room temperature to weigh.",
"They weigh the same amount, he's wrong.\n\nChanging the temperature of something only changes the weight if it adds things from or looses things to the atmosphere, eg a hot glass weighs slightly less than a cold glass because there is a thin film of water on all glass surfaces at room temperature.\n\nwhat is more likely is that the scales are not meant to handle hot things and the temperature will upset the mechanism it uses to determine the weight (eg if it uses a spring the spring will soften when heated)\n\n",
"You have to weigh them at a reference temperature so that you can *also* get their volume at the same temperature, and thus determine their density at that temperature."
]
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[],
[],
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367qu0 | what is the inevitable fate of earth and humanity right now? | explainlikeimfive | http://www.reddit.com/r/explainlikeimfive/comments/367qu0/eli5_what_is_the_inevitable_fate_of_earth_and/ | {
"a_id": [
"crbhcij"
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"score": [
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"text": [
"For starters, I have to wonder why you keep talking about NASA rather than a more relevant body like the Intergovernmental Panel on Climate Change (IPCC) who put out [a report every year](_URL_0_) that summarises the results of that year's research.\n\nThere is no 'inevitable' fate. For now, we're still in a position of being able to change the amount of warming (and hence the damage) that might take place as a result of human activity.\n\nThe earth's climate and atmosphere are the result of a number of very complex interlocking chemical systems, all of which have been extensively studied, but about which some unknowns still exist. To put it one way, what's not known is how elastic the earth's climate is - quite how much it's systems will respond to the changes currently taking place.\n\nPredictions about climate are very, very difficult. The further you go in the future, the more uncertain things become and I would call anyone who claims to know what the climate is going to look like in 500 years a fraud."
]
} | []
| []
| [
[
"http://www.ipcc.ch/pdf/assessment-report/ar5/syr/AR5_SYR_FINAL_SPM.pdf"
]
]
|
||
871aaa | if a defendant admits to committing a crime to their lawyer, they are still obligated to build a defense, so why are they not tried for perjury when they’re knowingly lying under oath? | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/871aaa/eli5_if_a_defendant_admits_to_committing_a_crime/ | {
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"dw9eop6",
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"text": [
"A lawyer can't purposely introduce testimony or evidence they know to be false. So for example, if I'm defending someone and their alibi is that they were at work and the evidence is a time card that's actually been falsified, if I know it that'd be a disbarrable offense. Though there's nothing illegal about simply instructing a client to be vague. Most defense lawyers try to have their client do as little confessing to them as possible while still learning enough to know what could blindside their defense or be a liability going in. ",
"I'm confused: do you mean the defendant or the lawyer?\n\nA lawyer mounts a defense for his client presenting the case as beneficially as possible. Whether he believes the client is guilty or not is not really relevant and in any case the lawyer is not under oath. He is not even necessarily lying when he says in his opening or summation that his client is not guilty, that is a legal term rather than a factual description.\n\nIn many jurisdictions the lawyer can't ask his testifying client a question to which he knows the client will lie in response. But even that is not a practical restriction; he can ask open-ended questions and he is under no obligation to *believe* his client when the client claims he is guilty; perhaps the client is confused or incompetent to know; perhaps he is shielding someone else. Lawyers are not judges or juries but advocates. ",
"The lawyer's not under oath. Neither is the defendant unless he is put on the witness' stand, and any competent lawyer wouldn't allow that."
]
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| []
| [
[],
[],
[]
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|
||
1siyxy | why are we bad at coming up with random numbers? | explainlikeimfive | http://www.reddit.com/r/explainlikeimfive/comments/1siyxy/eli5_why_are_we_bad_at_coming_up_with_random/ | {
"a_id": [
"cdy210o",
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"score": [
3,
4
],
"text": [
"Because we're good at finding patterns. We are strongly biased towards thinking in patterns.",
"Same reason that answering 'C' 4x in a row pisses people off. We tend to see patterns in short runs of random numbers, even if they are aperiodic. A more annoying response is that your brain is deterministic and therefore at best can only come up with pseudorandom numbers."
]
} | []
| []
| [
[],
[]
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|
||
81ahxs | what’s that weird sound when you’re about to drive off the highway or you’re on an interstate ramp? | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/81ahxs/eli5_whats_that_weird_sound_when_youre_about_to/ | {
"a_id": [
"dv1pvcb"
],
"score": [
6
],
"text": [
"The rumble strips? They're there to alert you you're drifting. It's to help prevent people from phasing out while driving or falling asleep at the wheel."
]
} | []
| []
| [
[]
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|
||
3z1e9v | how are all the roses used on floats at the rose parade kept to look so alive and healthy? | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/3z1e9v/eli5_how_are_all_the_roses_used_on_floats_at_the/ | {
"a_id": [
"cyiflkl",
"cyii6cj"
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"score": [
4,
5
],
"text": [
"They're still fresh. The floats get petals and other plant products applied to them as close to the parade as possible. Several years ago I helped on a float and there wasn't a single one in that building that wasn't still getting worked on the evening before the parade. ",
"_URL_0_\n\nSome of the flowers are placed in vials. When I was in highschool 20 years ago, we got a day off of school to volunteer taking apart floats. We had to pick the roses off the floats from the Rose Parade and separate the vials. The flowers were then dried to be used as potpourri."
]
} | []
| []
| [
[],
[
"http://www.afloral.com/Floral-Supplies/Water-Tubes-and-Picks"
]
]
|
||
bdi1sa | how do parent companies work? | Do the owned companies send a portion of their profit to the parent? For example: Disney owns ESPN. How does Disney make money off of that? | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/bdi1sa/eli5_how_do_parent_companies_work/ | {
"a_id": [
"eky9jxt"
],
"score": [
2
],
"text": [
"During contracts or legal takeover agreements they will normally decide what percentage of profits the child company (company that has been taken over) pays the parent company each month. \n\nI used to work for an insurance company and the department was where we paid the insurance brokerage commission when they sold one of our policies. During takeovers, they would send us either a copy of the agreement or a form designed by us (basically only asked for information relevant to us) in this it would stipulate what split the parent and child company got paid for commission earned each month. e.g 25/75 30/70 . \n\nIt's the same for when child companies do their finances each month, whatever they agreed percentage split wise, they have to pay to the parent from their profits."
]
} | []
| []
| [
[]
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|
|
3ilzeg | how do staffing / temp agencies work? | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/3ilzeg/eli5_how_do_staffing_temp_agencies_work/ | {
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"text": [
" > Why don't the places in my area looking for data entry specialists and office assistants and managers just post the jobs themselves? \n\nHiring people can be a pain in the ass. You have to interview, do background checks, fill out paperwork, provide benefits, etc. for any employee you hire.\n\nIt makes sense to do this if you need a full time worker. However, if you only need someone for a few months while someone in on maternity leave, it isn't worth all the time and effort. You'd rather pay a slight premium to a staffing agency who does all that work for you and just sends you an invoice every month.\n\n\n",
"The agencies may be putting those ads in for 'window dressing' without having a job to offer.\n\nSome companies will only hire from their temporary staff and only rarely then.",
"One reason that a company will use staffing agencies, as opposed to hiring directly, is because it's expensive to hire somebody. If they're unsure of the number of people they're going to need, they'll leave the hiring to the staffing company (actually, most companies use more than one staffing company to fill their workload).\n\nThis allows the company fast placements with the ability to easily \"terminate\" those employees, should the workload not be as large as the company anticipated.\n\nThere are also legal reasons regarding differences between 1099 employees and W-2, which could be a driving force for the company in making the determination between directly hiring or hiring through a staffing company.",
"Working for a staffing company isn't bad at all. That is how I got my current job. The company I work for has a contract with a large staffing agency to bring in suitable candidates for a desired position. They call it our training period. If for any reason the main company didn't want to hire us permanently, the agency would often have other jobs waiting for us. Plus, the agency posts the jobs as 'temp-hire', 'temporary', or 'seasonal'.",
"Let's say if you got hired through the company noramally you would make 11 dollars. If you are hired through the staffing agency you would make 10 dollars and they would keep that dollar left over. "
]
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[],
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5cqmk2 | why do cells use specifics genes instead of others? | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/5cqmk2/eli5why_do_cells_use_specifics_genes_instead_of/ | {
"a_id": [
"d9ynv0n"
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"score": [
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"text": [
"I think I get your question. First of all, there is a hierarchy of cells: totipotent, pluripotent, multipotent and unipotent cells. Totipotent cells (the highest 'order' of stem cells) can develop into any body tissue (including the placenta), while unipotent cells are highly specialized cells, such as muscle cells or neurons, and can never return to their stem cell form. Their functions are determined, set, fixed. \n\nWhy do certain cells develop into muscle cells while others develop into bone cells or neurons is determined during the embryological development. The complex interaction of cells, the activation and deactivation of specific genes and cytokines ('signal proteins') produced by other cells, all contribute to the differentiation of cells to undergo specialization and finally become unipotent cells. Once they are specialized, most genes are deactivated and only the relevant genes for their functions are available to be activated. Activation can be influenced by hormones and cell-cell interactions."
]
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| []
| [
[]
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|
||
6y47g5 | how do completely autonomous vehicles navigate parking lots? | Seems to me like parking lots have some of the most unpredictable driving conditions. How does an autonomous vehicle decide which spot to take? | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/6y47g5/eli5_how_do_completely_autonomous_vehicles/ | {
"a_id": [
"dmkktnq"
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"score": [
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"text": [
"Autonomous vehicles usually use a combination of stereoscopic cameras and LIDAR to build a 3D map of the local vicinity:\n\nStereo cameras use the slight differences between the images perceived by two side-by-side cameras to determine how far away something is. (Try closing one eye then the other, closer objects will appear to move left and right more than distant objects)\n\nLIDAR is a system that sends out a signal and uses the time for it to bounce off an object and return to determine the distance to that object. \n\nBy combining these a 3D map of the space around the vehicle can be created. From this, machine learning algorithms are used that have been trained to recognise common object like cars, vans, people, bollards etc... The training process is a little hard to understand, but it basically works by 'showing' the sensors examples of objects you want the car to recognise and asking it what it is seeing. If it identifies the object correctly, take no action, if it identifies the object incorrectly or fails to identify the object, a small change is made to the identification program until the deemed probability of what the object is moves in the direction of correct identification. Then another object is show to it and the process is repeated. A lot.\n\nThis object recognition and 3D scene map are combined to place objects around the car in a 3D map. Additionally gps information can also be used to tell the car it is in a parking lot. \n\nUsing the object location in the 3D map, the car can find spaces between cars that correspond to parking bay sizes and the parking procedure can be started. \n\nIn terms of avoiding collisions these cameras and LIDAR are constantly scanning the area around the vehicle and have the ability to very quickly stop the car if the scene should change I.e. a car moves, or a person steps in front of the vehicle.\n\nI hope that was somewhat helpful. It's a tough one to explain to a 5 year old.\n"
]
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[]
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3y74wz | why are desktop processors still faster than phone processors if their gigahertz is the same? | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/3y74wz/eli5_why_are_desktop_processors_still_faster_than/ | {
"a_id": [
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"Because they use more power. Your cell phone isn't plugged into a wall and can't draw hundreds of watts, so the instruction set and processor is designed to be ultra power efficient. That comes at the cost of speed. \n\nWith that in mind, clock rate is a terrible metric of processing power. It meant something ten years ago, now processor power is more based on instructions per clock, rather than clocks per second. "
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g1wha7 | difference wifi booster extender vs repeater | Look to get proper WiFi signal in all rooms of my house. Large home. What to look into? | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/g1wha7/eli5_difference_wifi_booster_extender_vs_repeater/ | {
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"The best option is an extender, which uses a wired connection. If you can run an Ethernet cable between two rooms, or if you could use a Powerline adapter, then you'll essentially have two (or more) Wifi access points that are both equally fast and powerful. If you want absolute maximum speeds, have your house wired for Ethernet and put an extender in every room.\n\nThe next best option is to get a \"mesh\" system like Google Wifi, Orbi, Eero, or Deco. They create a fast point-to-point wireless communication between all of the nodes throughout your home on a totally independent wireless channel (not over Wifi) and they all work together to blanket your home in Wifi. These devices are more expensive but they're super simple to set up, they require no extra wiring, and they work great.\n\nThe worst option is to get a repeater. What that does is connect to your main Wifi access point, and then broadcast a new Wifi access point from another room. When a device talks to the repeater, it has to receive that message and then send it over to your main Wifi access point over Wifi. This is better than nothing, but it actually increases the total amount of interference because that extra communication is all happening over Wifi. It tends to give you higher latency and slower bandwidth overall.\n\nNote that any Wifi router can be configured to act as an extender or a repeater. If you have a spare, you can repurpose it.\n\nThe term \"booster\" is generic, it refers to any of these.",
"A repeater has to send your data packets over WiFi to talk to your router.\n\nAn extender sends your data packets to the router through an etherenet cable, which has lower latency (time taken to get data from A to B) and a higher bandwidth (amount of data you can squeeze through a connection per second)"
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4c7446 | why can some people sense changes in the weather coming in their injured body parts? | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/4c7446/eli5_why_can_some_people_sense_changes_in_the/ | {
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"Weather patterns result in changes to barometric pressure. Changes to barometric pressure results in measurable changes to the pressure within joints. People with and without injuries can sometimes feel this, but additional scar tissue, additional \"parts\" can all make it more acute, or our brains more focused on those particular parts/places.",
"Rain is often preceded by a sudden drop in barometric pressure, which basically means that everything liquid from your body to your bottle of mountain dew will very slightly swell as the pressure falls.\n\nThis swelling within your body is so slight that is will go unnoticed expect where scar tissue is present because scar tissue isn't as flexible as the tissue it replaces. \n\nThe pain you are feeling is actually not from your bones but from the periosteum, which is the thin layer of tissue that coats the bone.\n\nThis tissue is normally quite stretchy and sensitive because it has lots of nerves, but when you break a bone and some of that periosteum is replaced with inflexible scar tissue you will feel pain when the nerves surrounding it swell and pull on it.\nThis is also responsible for the less well known phenomena of people being able to predict the weather using old soft tissue injuries like deep lacerations that have healed."
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3hv96f | if a person jumped out of a plane and lightning struck him, would he absorb the whole beam or would the lightning continue down to the ground? | explainlikeimfive | http://www.reddit.com/r/explainlikeimfive/comments/3hv96f/eli5_if_a_person_jumped_out_of_a_plane_and/ | {
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"no chance he would \"absorb\" the beam. The act of lightening is the flow of electrons, of which he does not have nearly enough to neutralize the imbalance (nor is a human notably charged to release them)\n\nIt would go right through him, and fry him in the process.",
"Lightning is basically nature's way of balancing electrical charges in the sky with the ground. People don't \"absorb\" lightning strikes. The lightning passes through them (causing damage to any cells it passes through) to the ground.",
"And to add on to that..\n\nIf he DIDN'T absorb the lightning bolt, would he travel with it and appear on the ground faster than if he wasn't struck with it at all?"
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2yi9f4 | why is it that when a pen runs out of ink, i can write somewhere else, even the same letter, perfectly fine, but when i go back to write where i was originally, the pen refuses to let out ink? | explainlikeimfive | http://www.reddit.com/r/explainlikeimfive/comments/2yi9f4/eli5why_is_it_that_when_a_pen_runs_out_of_ink_i/ | {
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"You are using a ballpoint pen I take it? In order to write the ball must turn, but the paper was smashed smooth where you were behind.",
"If the pen were truly out of ink, it wouldn't write at all. ",
"Generally, this is caused by some oil or grease on the paper. It lubricates the surface so the ball won't turn, as well as preventing the water-based ink from sticking to the paper.",
"The question was answered but I want to share this little tip:\n\nIf you think your ballpoint is out of ink hold a lighter flame to the ball tip for a moment, careful of the plastic and don't do this in class. Usually melts whatever dried ink clog there was or expands the metal enough to let ink flow again and you can keep on writing.",
"Two reasons. One, the paper may have picked up any excess sweat/grease on your hands. And two, should you rest on the paper for too long, you compress the fibres of the paper, making it flat. Ballpoint pens have a hard time writing on these, as they require friction to rotate the ball in the tip and release the ink."
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5n31wf | how do pet rats differ from wild rats? | [deleted] | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/5n31wf/eli5_how_do_pet_rats_differ_from_wild_rats/ | {
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"Pet rats are domesticated and are much more robust in build. They tend to be calmer and gentler and have evolved and adapted to a captive lifestyle with humans. Wild rats are...leaner, more twitchy, aggressive, still actively forage and hunt for their food. If you were to have a pet rat and a wild rat in the same room they would be immediately differentiator. The pet rat would most likely be leisurely exploring or cuddling into a lap or a shoulder, the wild rat would be running around the room at the speed of sound, jumping, probing, and most likely trying to escape from your very presence. ",
"Ehh rats are still instinctive animals and I'd assume that even pet rats would eat each other if left to starve. Pet rats bond almost inseparably with each other and their humans given proper interaction so they would have to be left for a very long time. Lab rats will kill each other even though they're technically \"pet rats\" but scientists actually work with them over mice because they are much less likely to bite. Wild rats have been fostered from birth or very young and been semi tame but they still act incredibly wild. A rat caught in the wild or from sexual maturity will never become tame and switch normally be very aggressive if cornered or just avoid you if not. Pet rats generally don't bite unless they haven't been socialized or you startle them and they're unfamiliar with you, anything is possible but generally rats are very gentle if socialized as pets and shouldn't bite babies. If you are considering getting one however I wouldn't let it near the baby because they like to pee as they walk and you can make your baby very sick.",
"_URL_0_ here's a great example"
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2z7zq6 | why the audio/sound button on the electronic devices (e.g tv) is called "volume"? | explainlikeimfive | http://www.reddit.com/r/explainlikeimfive/comments/2z7zq6/eli5_why_the_audiosound_button_on_the_electronic/ | {
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"Because it controls how big a volume of air the sound can fill. \"Audio\" or \"sound\" would be bad choices to label that, because both are too generic - for instance the \"sound\" button could control pitch, and it would still be an accurate description.\n\nIf you want a more accurate term for the volume button, try \"amplitude,\" or \"gain.\"\n\nEDIT: I forgot attenuation, which is technically correct but is counter-intuitive. It is nonetheless used in lots of more high-end and professional audio equipment.",
"Nigel Tufnel: The numbers all go to eleven. Look, right across the board, eleven, eleven, eleven and...\n\nMarty DiBergi: Oh, I see. And most amps go up to ten?\n\nNigel Tufnel: Exactly.\n\nMarty DiBergi: Does that mean it's louder? Is it any louder?\n\nNigel Tufnel: Well, it's one louder, isn't it? It's not ten. You see, most blokes, you know, will be playing at ten. You're on ten here, all the way up, all the way up, all the way up, you're on ten on your guitar. Where can you go from there? Where?\n\nMarty DiBergi: I don't know.\n\nNigel Tufnel: Nowhere. Exactly. What we do is, if we need that extra push over the cliff, you know what we do?\n\nMarty DiBergi: Put it up to eleven.\n\nNigel Tufnel: Eleven. Exactly. One louder.\n\nMarty DiBergi: Why don't you just make ten louder and make ten be the top number and make that a little louder?\n\nNigel Tufnel: [pause] These go to eleven.",
"Sound is a property of physical vibration, so it needs a medium to propagate through, and it fills a 'volume' similar but not the same as a liquid. Perceived loudness can be very high while the actual volume can be -2db... thats all EQ/mastering on the sound to make it fill the space a certain way.",
"Volume is defined as \"A measure of the loudness or intensity of a sound.\" Therefore, it makes since that adjusting the loudness of the sound coming from a device would be called volume. \n\nvolume. (n.d.). The American Heritage® Science Dictionary. Retrieved March 16, 2015, from _URL_1_ website: _URL_0_",
"[Semantic development of \"volume\" in English](_URL_0_):\n\n* roll of parchment containing writing; a bound book (late 14 c.)\n* book forming part of a set (1520s)\n* bulk or size of a book (1520s)\n* bulk, mass, quantity (1620s)\n\nThe phrase \"**volume of sound**\" is a natural application of the \"bulk, mass, quantity\" meaning. It occurs in a [review of the third performance of Handel's \"Messiah\"](_URL_2_) from 1784.\n\nCredit: /u/gnorrn\n_URL_1_",
"How about the volume of the wave itself?",
"In french volume can be said for the strength of a voice (think to opera singer) and so it can be a reference to the volume of the lungs.",
"Follow-up please. The vibrating cone shapes a wave in opposition to pressure of the exsisting atmoshere, right? So, whatever you name (da, da or da) it it is just a very rapid vibratory movement of a cone shaped mass, yes or no."
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"http://www.reddit.com/r/etymology/comments/2o848r/use_of_the_word_volume_to_describe_sound/cmkn2ke",
"http://books.google.com/books?id=wroPAAAAQAAJ&pg=PA423#v=onepage&q=%22volume%20of%20sound%22&f=false"
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2xkjix | what is with all the half life 3 hype? what makes 1 + 2 so amazing that 3 is the unicorn of future games? | explainlikeimfive | http://www.reddit.com/r/explainlikeimfive/comments/2xkjix/eli5_what_is_with_all_the_half_life_3_hype_what/ | {
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"Half-Life 1 is a classic and is considered one of the greatest FPSs of its era, if not of all time. It was pretty revolutionary in terms of level design and style of storytelling, and gave birth to Counter-Strike (originally a mod, as were Team Fortress and Day of Defeat) and made Valve an important name in the industry overnight. It won more than 50 game of the year awards, and was for many years the best selling PC FPS ever.\n\nHalf-Life 2 was similarly well received, and was considered pretty revolutionary particularly in its use of physics. It got unbelievably good review scores across the board, a ton of game of the year awards, and a lot of reviewers (to this day) consider it the best video game of all time, bar none. It also launched the Source Engine, which is one of the most important video game development tools of the past decade, and Half-Life 2 also helped to launch Steam, which is (obviously) the biggest and most important digital games retailer and pretty much single-handedly revolutionized the PC game market economically. "
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9pcg4k | how much of a temperature increase would there be if you poured a boiling kettles worth of water into a hot bath? | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/9pcg4k/eli5_how_much_of_a_temperature_increase_would/ | {
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"How much water is in the bath? How much is in the kettle? How hot is the bath water?"
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7urn8x | how does someone that was born and raised in another country choose a "western" name when they immigrate to western country? | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/7urn8x/eli5_how_does_someone_that_was_born_and_raised_in/ | {
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"Some Western names are English translations of names in other languages, and some Western names just sound like names in other languages. Also, there are Christians all over the world so there might actually be Vietnamese people named Anthony or Vincent.",
"Sometimes by suggestion. The gas station around the corner had a young Indian lady whose name tag read : Mandeep. Everyone greeted her with a smile. A few weeks later her name tag read: Mandy. ",
"Many times it is just a short form or derivative of the original name. For example, Balwinder becomes Bill, and Gursher becomes Gary.",
"Speaking for Indians, a lot of names have a western twist to them. India does have a sizable Christian and Catholic population so western names are pretty common in those communities. As for punjabis, I'm not one myself but it's pretty common for them to have western sounding names like Jimmy or happy, bubbly etc."
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9a6vfx | difference between ny stock exchange and nasdaq? | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/9a6vfx/eli5_difference_between_ny_stock_exchange_and/ | {
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"The NYSE started all the way back in the 18th century, and the Nasdaq only started up in the 1970s. The Nasdaq was originally just for information purposes, and only later became a stock exchange. Because of this, the Nasdaq is where more cutting-edge companies chose to list themselves, while old stalwarts still join the NYSE.",
"There seems to already be some good answers here, but if you need more and have Netflix, there’s a series called ‘Explained,’ and the stock market episode (which is only like 15 minutes long, so it’s not a huge commitment) is easy to follow, goes into this, and may be helpful if you’re a more visual learner! ",
"The New York Stock Exchange is the oldest and largest exchange in America used to buy and sell stock. The National Association of Securities Dealers Automated Quotations has only been around for roughly 50 years and has grown to be the second largest exchange in the US by introducing a level of technology that was not previously Incorporated in stock trading at the time, namely the ability to process trades electronically, get the most up-to-date quotes on stock prices, and minimize the gap between the bid and ask prices (this didn't go over well with brokerage firms who depended on a larger spread for their commissions but obviously investors liked this change).",
"Your company has to do $5 million annually to be listed on the Nasdaq. Your company has to do $50 million annually to be listed on the NYSE. That's why it's called the \"Big Board\". Also, Nasdaq lists companies in \"North America\", thereby allowing Canadian companies to be listed."
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a3z6w2 | why are dots and dashes the only acceptable non-alphabetical/numerical characters in usernames on social media sites and message boards? | Like is there any specific reason as to why other characters cannot be accepted, like an asterisk or a currency symbol? | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/a3z6w2/eli5_why_are_dots_and_dashes_the_only_acceptable/ | {
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"In programming, certain characters are reserved as special characters. These characters vary by programming language, so it's easiest to just prohibit all of them. \n\nWhy is this a problem? A lazy programmer might take the provided username and simply drop it right into their code. This means that a malicious user could create a username that intentionally makes the code do something it's not meant to do. This is called an \"injection attack\". \n\nAnd there are plenty of good non-malicious reasons too. For instance, the $ symbol looks like a capital S, so that presents issues with readability and username forgery. ",
"Some symbols may be hard to type on some layouts.\n\nFor instance things like an € or a £ may not be anywhere on an user's keyboard. If you need to write an user's username, it's useful to be able to actually do it. For some symbols they may be unusal enough that the person that needs to type it wouldn't know what it's even called, and asking \"how do you type a weird bent squiggly thing\" isn't going to get very far.\n\nThe same goes for accents. In the US and the UK, they're not seen much at all. They're also quite varied. Compare: áéíóú and àèìòù.\n\nThen there's the matter of encodings. While these days UTF-8 is thankfully in a lot of places there are still legacy systems that don't use it, and where something like an £ may not exist at all.\n\nAnd then, there's an additional bit of fun. Different languages have identical looking letters to English ones, but which to a computer, are different. Let's say I registered myself as \"dаlе_glаss\". Go and try to search for it with Ctrl+F by typing it in the search box (without copy/pasting) and see if you find it in my comment.\n\nOverall, allowing people use whatever random thing they please in usernames allows for a lot of corner cases and confusion.\n\n**Edit:** typo",
"A lot of these characters don’t work in URLs, or at least not across all browsers, so only safe ones are accepted so you can have urls like _URL_0_\n\nThere are some security concerns also with some characters as they can be used for “injection-style” attacks on databases but most modern platforms are protected against that these days.\n\nI’d also suspect most platforms keep the allowed characters to the strict minimum to prevent you from coming up with something you’ll never remember yourself.",
"I think the short answer to your question is \"No, there isn't any specific reason why other characters cannot be accepted\".\n\nSo why do sites limit usernames this way?\n\nThey don't all do so, of course -- some limit them in other ways (underscore can be used sometimes), some allow only alphanumeric. \n\nHaving them limit the characters they accept makes it a little easier to use the usernames in some programming situations. For instance, some programming libraries use asterisk (\"\\*\") as a 'wild card' character, matching 0 or more characters; someone doing a search for \"al\\*\" will match albert, alvin, and al; if the program allowed asterisks in the username, then programming code to search for a name would have to search the name for asterisks and mark any asterisk specially so that it meant a real asterisk, not an asterisk that meant a wildcard (\"al\\\\**\").\n\nCommas, as another example, are often used to separate fields of data; there are situations where the string \"al, becky, charlie\" means 3 first names. If the program allowed commas within the names, then in any situation where they might be used in a list, programming code would have to search each name for a comma and mark it, and programming code getting the name would have to look for the special mark and remove it.\n\nSo it's easier to just say \"They don't need those characters, we'll ensure that they don't get into any usernames.\"",
"In addition to what everybody said, there's also a Unicode problem where a sequence of codepoints could look like another sequence.\n\nFor example:\n\n* ; and ; are different codepoints.\n* Code point U+200F makes text go right-to-left but would be technically invisible in a username.\n* There are more so-called invisible codepoints which would be unnoticable.\n\nYou could remove any of these fancy things, but then suddenly you're back at square one, and also people suddenly occupy multiple usernames, one with the invisible codepoint and one without (GMail works like this, where `FearfulGoose` and `Fearful......Goose` point to the same account). \nThe easiest solution would be to just disallow such characters.",
"We give people usernames because it provides us a recognizable identifier we can use *everywhere* to refer to one specific person\n\n*Everywhere* can potentially include the front of email addresses, URLs, filenames, links, etc as well as places we haven't even thought of yet. All those different places have different rules about what characters you can use, and what they do when you try to use the ones you can't.\n\nFor example, if I wanted my reddit username to be `the?mighty?chris`, my reddit URL would have to show up like `_URL_0_` because `?` has special meaning in URLs and the rule for using those characters without their special meaning is to replace them with those `%XX` stand-ins. If you're used to knowing me as `the?mighty?chris` you might not recognize me in that URL at a glance because those stand-ins can be distracting\n\nMany other answers have focused on how programmers forgetting to change special characters into their stand-ins can cause problems and saying it's safer to just forbid them. That's not really why they're always forbidden in usernames though, websites already deal with lots of other places where you can type any characters you want.\n\nThe real reason is that even when you succeed in handling the special characters correctly in every place, you'd still be defeating the whole point of having a username by making it ugly and less recognizable\n\nSo, the traditional constraints for usernames are really about adhering to a lowest-common-denominator of characters you can use *everywhere* present and future **without needing to make them unrecognizable**.\n\nThis particular set of characters probably came to be the lowest-common-denominator because they're ones programmers would commonly use while naming files. Dots became common with the convention of file extensions (e.g. `.doc`) to indicate the type of a file, and hyphens/underscores became common alternatives to spaces because spaces look like breaks when you have columns of data on your screen. Programmers always want to be able to recognize their filenames easily so it's always been a priority to keep those characters usable without any stand-ins by choosing different characters when they need to find ones to give special meanings to",
"Some characters are not accepted because they have a syntax meaning. That is, they control how a block of text is interpreted.\n\nThere aren't any characters that are universally special. Some might be special because of how the username is used. For example, in Twitter, usernames can appear in tweets like so: \"I saw @joe just yesterday!\". The @ special character marks the start of the username and a space marks the end of the username. So those two characters should be reserved. If they allowed spaces, for example, how can you tell they're not referring to the user \"joe just\"? For the same reason, they bar other punctuation characters, so that an @username can fit into normal English writing.\n\nSome characters are special for more \"internal\" reasons. For example, a Twitter's user page is \"_URL_0_\". In URL syntax, the forward-slash is character with special syntax. It'll cause trouble, then, if the username contains one.\n\nOne ugly kind of internal-use special-character ban is to prevent code injection. (See other comments on code injection.) It exists because programmers are bad. Such is life.\n\nMost of the other \"standard\" special character restrictions go back to Unix filename conventions. Tons of places that special characters show up (like URLs) are ultimately patterned after how you name files in Unix. While few if any characters are actually disallowed, most special characters are avoided because they have special meaning to the command-line shell. People stick to alphanumeric and dot, dash, and underscore.\n\nOther characters are disallowed because they'll cause trouble or confusion for users -- like crazy Unicode tricks. At that point, it's easier to make a limited list of allowed characters rather than try to figure out how to make a list of everything that should be disallowed.\n\nTLDR: Usernames are a-zA-Z0-9.-\\_ because that's how you name things in Unix. Go figure.",
"\n\nSome people mentioned that some characters are reserved, but the can be escaped or encodes, so it's not a real problem.\n\nThis would work for #, @ minus, dash, :, & , % and so on.\n\nAlmost everything has a database behind it nowadays, the information is stored there permanent.\n\nSome character-combinations can used to delete a whole database, or output more than you should see (sql injection). Worst case, someone manages to add a user with the highest possible privileges, so they could easily 'walk in' and see the content.\n\nBut, what I suspect is: simple readability.\nPerskes, per_skes and persk-es is simply easier to read than < P!e=rs@k+e€s > .\n\nBy the way, don't remember that, as it is my password everywhere.\n\nAnother reason why security is not a valid excuse: I can type ever single of the reserved characters into a tweet. The text is stored in the same database and requires the same care when sanitizing the inputs and outputs.. ",
"For a real ELI5, maybe even ELI3: have you ever seen those memes where people are playing a game, and there's a dialog option where an NPC says \"good job [username]!\" And then someone makes their username \"killing all those people\" and it makes the NPC say \"good job killing all those people!\"\n\nWell in the same way, using special characters would make the program DO bad stuff, like run mean virus programs, instead of harmlessly making an NPC say something naughty. ",
"All of your input has to be sent to a computer program. That program has to save the inputs you gave it. But the most common kind of program for that takes commands in the form of text. So a person familiar with the right magic words can pretend they want a username that looks like the magic words to make the computer do bad things. \n\nMost of the magic words to do bad things involve punctuation marks. So if your input is not allowed to use those punctuation marks, it's much easier for the programmer to be certain you can't tell his computer to do bad things.\n\nYou might ask, \"Why don't they make it so that there's a safe way to use the punctuation marks?\" They saw that coming. The people who wrote the programs did do that. But if the programmer decides the punctuation can be used in usernames, then *everything* that uses the username within their program has to carefully convert the punctuation to safe values. It only takes one mistake in thousands of lines of code to break everything.\n\nAlso, sometimes the code that checks for the stuff to substitute runs relatively slowly. Very mean people can create strings of \"perfectly legal\" text that take a very, very long time to inspect. Then they write programs to throw a lot of that text at the programs in order to overload the servers. That can cause servers to crash. Or they can get so busy they can't respond to other users. You never want to allow random people to do this to you.\n\nSo it is much safer to never allow punctuation, and aggressively reject any input that contains it.\n\n(Punctuation is allowed in passwords for a different but simple reason: generally the password you type isn't sent to the program: it is converted to a number with some math that is supposed to make it impossible to figure out exactly what the text was. Numbers don't have punctuation. It turns out there's no good reason to disallow characters in passwords, and often disallowing certain characters makes them *less* secure. But that is a different question.)",
"Some even restrict it to ASCII. The issue is especially when you allow unicode characters because with unicode characters you can do a lot of trickery such as reversing text direction or using symbols that look the same but are different characters according to unicode at which point you wouldn't be able to tell two users apart because their name while different is printed the same way. It also makes some things easier to deal with because you don't have to escape anything. For example when you'd create a directory based on the name of a user then you'd have to take additional care to escape characters EXCEPT that there are no escape characters for filenames so you'd have to come up with a replacement scheme that is unique and doesn't accidentally map two different names to the same name for example if you'd replace \\\\ with \\_ in a name then the user hi/there and hi\\_there would have a name collision. ",
"Because it's the [POSIX Portable Filename Character Set](_URL_0_)\n\nEven though it's usually not used for filenames, the same underlying reasoning applies.",
"There’s no reason to disallow them. Because of injections you still have to be careful about ANY user entered data. So one might as well handle every character.\n\nThere are times in which a user name might embed other info with it inside the product so you wouldn’t want the name to include it. Think about email addresses as usernames. One would not want the @ sign to be used.\n\nOther than that it’s just lazy programming. And so users can’t make crazy names. ",
"A computer is like someone who speaks a different language. Code is the language the computer speaks. When we put in usernames, passwords , etc the computer is not understanding what you're saying. It's just looking at what goes in the box, and saying \"okay! That's a username, it went in the username box! I'll put it with all the other usernames!\"\n\nHowever, certain characters (; # @ $ & ... Etc) are used in the computers language a lot. The computer may see these characters and think \"ooh, this isn't a username. This is a message for me! An instruction! Yay!\" And it will not treat it as a username, but will instead listen to whatever is written. Even if what's written is \"transfer all your important secret stuff to me pretty please\". \n\nNote : if you train your computer friend well, it won't listen to the little snippets of words in the box. However people are paranoid, and prefer to avoid any risk of this entirely. "
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31l9ia | what is the circadian rhythm? is it really that important to maintain this rhythm for sleep? how does it relate to overall health? | explainlikeimfive | http://www.reddit.com/r/explainlikeimfive/comments/31l9ia/eli5_what_is_the_circadian_rhythm_is_it_really/ | {
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"Circadian Rhythms are physiological cycles of organisms based on the day cycle- typically dominated by the influences of the sun/light cycle (e.g. the opening and closing of flowers). Effectively, different parts of the body are active during specific parts of the day. This typically entails that certain enzymes are more active during the day (or night) because regulatory processes increase production of said enzymes. The regulatory processes can be something as simple as presence of sunlight to a combination with hormonal control (particularly in us humans).\n\nIn mammals, a particular set of regulatory proteins are the suspects for helping to regulate the circadian rhythm- the [CRY proteins](_URL_1_). The linked article associates these proteins with general health (i.e. functioning of the body). Basically, your body is meant to do specific things at certain times of the day such as eating, sleeping, etc.\n\nMaintaining these activities with your circadian rhythm is suggested to be important to health. [Trials with mice](_URL_2_) show all kinds of issues when they are exposed to just food at the wrong time in their day\n\nAs far as sleep, there is a particular time for us to go to sleep. However, I believe REM plays a stronger effect in determining the quality of our sleep. I was trying to find a decent article to show that waking up in the middle of deep sleep is bad and et cetera, but unfortunately I need to catch a few REM cycles myself. However, certain physiological responses of the circadian rhythm also do play a role. For example, your blood pressure raises in the morning supposedly as an attempt to help get you up.\n\nTL;DR Circadian rhythms essentially lay out a day plan for your body. Your body is more adapt to doing certain activities during certain parts of the [day.](_URL_0_) Maintaining the proper activity with the proper time of the day is indeed suggested to be responsible in the upkeep of your health- sleep included.\n"
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4bjq37 | how does your brain know if your tongue is tasting something sweet or sour? | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/4bjq37/eli5_how_does_your_brain_know_if_your_tongue_is/ | {
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"The sense we call \"Taste\" is actually sensing the chemical makeup of whatever you're putting in your mouth. Various nerve endings in your taste buds will only send a signal to your brain if they are triggered by a certain chemical. Since different foods have different combinations of chemicals, we experience each as a unique taste. Essentially, your brain gets a combination of chemical signals from your tongue and labels that specific combination \"corned beef\" or \"Mountain Dew.\"",
"Specialized nerve signals. Some for sweet, sour, bitter, umami. Then your sense of smell helps out.\n\nIt's the same way we know if something is cold or hot when we touch it (that's why mint can fool us into feeling \"cold\" when it's not actually cold. It fires our nerves that are meant to feel cold.)"
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bnu742 | what do power companies do with excess electricity? | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/bnu742/eli5_what_do_power_companies_do_with_excess/ | {
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"There is no excess electricity. The consumption is constantly monitored and the production rate is modified according to it.",
"There isn’t an excess of energy per se. the generators themselves are only excited enough to produce the current required. \n\nEg: \ncurrent demand is say 1000kw\nI have 5 gens capable of 250kw each\nTotal capacity = 1250kw\nI can run 5 at 200kw, or 4 at 250kw\n\nIn the 5 gen scenario, I won’t excited the rotor field enough (ie: run them at 80%) to prevent overloading and allow for transient current demand responses.\n\nI can’t change the speed of the generators (normally) because this would affect your 60 or 50 hz frequency that comes out of the wall plug (depending on grid). \n\nThis is a function of poles in the generator and operating rotational speed. Eg: A 4 pole generator on a Diesel engine generator must run the engine at 1800rpm for 60hz or 1500rpm for 50hz. Hence why I can’t speed them up or slow them down without consequence.\nHTH\n\nEdited spelling of generator.",
"That's not how electricity works. If the electricity is not being used then there is no current flowing so all you have is potential \"for electricity\". When people start \"using electricity\" then current starts to flow and the generators at the power station become harder to turn. The power station then has to burn more fuel to keep the generators turning.\n\nSo essentially the power station powers the generators, by burning coal, gas, nuclear etc, according to demand."
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g0ubhx | i’ve recently learned that babies are really good at dealing with broken bones because their bones are similar to cartilage. how do they form into “adult bones”, and how long does that process take? | IIRC babies have like 300 bones at birth, and that number gets closer to 200 with age. How do the bones fuse (I hope that’s the right term) together, and when does this process generally stop? | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/g0ubhx/eli5_ive_recently_learned_that_babies_are_really/ | {
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"Yes, the correct term is bone fusion. Essentially baby bones function a lot like a “broken” bone in that the cells add extra calcium as they grow, hardening them. And if you’ve ever heard the term “growth plates” those are pieces found on the ends of long bones (the bones in your arms and legs) that fuse to help lengthen a bone as a child grows, so if one is damaged in an injury, abnormal growth of a limb can occur if the injury isn’t treated properly. Skulls are made up of many plates that fuse together as a child grows as well. Their heads actually need to be quite “squishy” to fit through the birth canal. The whole process of fusion/no further growth in height generally coincides with puberty. Bones continue fusing as a person ages, which is why the fusion lines on a 90 year old’s skull are barely visible, but on a 20 year old’s are solid, but highly visible."
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3eifg0 | bill gates wakes up one morning and hands everyone in the united states 200$ (~60bn$). what happens to the economy? | explainlikeimfive | http://www.reddit.com/r/explainlikeimfive/comments/3eifg0/eli5_bill_gates_wakes_up_one_morning_and_hands/ | {
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"This is not much different than [The Economic Stimulus Act of 2008](_URL_0_) which gave most tax payers a $600 check back.\n\n > Impact:\n\n > The researchers found that the stimulus checks increased spending for the typical family by 3.5% when the rebate arrived, boosting overall nondurable consumption by 2.4% in the second quarter of 2008. The study concludes that the rebate payments for U.S. households were an effective stimulus method by increasing disposable income\n\n[per wikipedia]\n\nSo it increased spending a little bit, at $200, you can just roughly assume these numbers will be at least 1/3 less, which makes them really small, so much that we don't care that much, less than 1% is just natural variation stuff.\n\ntl;dr: At $200, not much effect."
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cbmale | why is it that when we're tired from exercise we feel the need to bend down? | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/cbmale/eli5_why_is_it_that_when_were_tired_from_exercise/ | {
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"because the diaphragm contracts more easily when horizontal, because gravity affects it when you're vertical (upright)\n\nwhich allows for easier, deeper breaths"
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3m7lm3 | - why are environmentalists against the keystone pipeline? that oil is going to be transported one way or another. isn't using a pipeline cleaner and safer than using boats or trucks? | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/3m7lm3/eli5_why_are_environmentalists_against_the/ | {
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"Transporting oil more cheaply and efficiently will lower prices, leading to higher consumption.\n\nTo go the opposite direction, requiring each gallon of oil pumped to be personally read a bedtime story would make the oil more expensive, and would lead to lower consumption.",
"A lot of the pipeline goes through farm land which is crucial for irrigation in certain areas ",
"One of the reasons is their opposition to how the oil will be mined in Canada. They argued it will bring massive environmental damage to the areas where the oil will be mined.",
"If the pipeline has a spill over the Ogallala aquifer, it could potentially spill much more oil at once than a truck or train. ",
"Ish. The problem is the magnitude of the consequences of failure. Transport but truck (or rail) increases the odds of an environmental accident over a pipeline. However, if the pipeline fails, the scale of damage will be exponentially larger. First, there's detection. We have to know there is a failure (yes , there are sensors but expect a delay). We then have to locate the failure. Finally we have to fix the failure. All that time passing is dumping sludge worse than just crude. Add the areas at risk, and we could destroy the aquifers feeding half of our farm belt. Compare that to a truck accident. ",
"*Sigh. I think if you sat down with Greenpeace and asked them for the whole strategy on this they would say that they are going to, method by method, do everything they can to frustrate and stop the extraction of this oil - period.\n\nWhich is fine from the perspective of a fanatic, but is deeply flawed in the real world where there is a realization that this oil will be pumped, it will be sold, and the only question is what is the least harmful way to do that (the answer to which is a pipeline).\n\nThe worst part is that politicians, wanting to find compromise and not really caring about the ultimate consequences because they are protected from them (lets say there is a huge oil spill from a tanker, the politician says \"I was doing what the environmentalists wanted when i voted against the pipeline that would have prevented this. How was I to know?\").\n\nWho gets hurt? Average people. Who is helped? No one.",
"The agriculture industry spends a tremendous amount of money on government lobbying and educating the public that fossil fuels are the leading cause of Global Warming. \n\nThis is to distract from the fact that the meat and dairy industries are - by far - the biggest contributors to Global Warming, and to the current water shortage.\n\nBy focusing media attention on the evil oil companies, people can feel better about eating meat. \n\n_URL_0_\n\nEDIT: Similar to the way anti-smoking campaigns - which are paid for by tobacco companies - only show cool, rebellious, independent teens experiencing smoking as a dangerous, forbidden pleasure. ",
"Also, isn't this a pipeline that will be connected other pipelines? Aren't there hundreds of pipelines? And have been for decades? What's the big deal?",
"The pipeline also crosses the Oglala aquifer, the largest in the United States that supplies water to most of the west. This water table is only feet from the surface in most areas where this pipeline will cross. One leak and the water for a significant portion of the country would be devastated leading to unspeakable damage economically and environmentally. ",
"It's not an environmental concern, but my biggest issue is various studies have suggested that by diverting crude away from refineries that focus on gasoline supplying the Midwest into refineries that prioritize other petro products and exportation, this pipeline will actually and counterintuitively increase gas prices in the states. Not preferable. ",
"The way OP has posed this question is a false dichotomy. Either we have the Keystone Pipeline, or the oil will come in a riskier way. There are other options.\n\nWhy do people oppose the pipeline? Two primary reasons:\n\n* They oppose drilling the tar sands in Canada, which is a highly experimental and incredibly damaging method of extracting oil. It requires destroying forests and using immense amounts of fresh water which will be ultimately contaminated/wasted. It is tantamount to \"strip mining\" for oil. Read more at [this Wikipedia article](_URL_0_)\n\n* The [\"Not In My Back Yard\" (NIMBY) factor](_URL_1_). Nobody wants to live near an oil pipeline. In the event of a disaster, the environmental damage is quick and immediate, while the cleanup is usually slow and inadequate.\n\nThose opposed to the Keystone Pipeline want energy producers to develop alternative energy methods, and stop trying to squeeze the pejorative \"blood from the stone.\" There are many other fuel sources available besides oil.\n\nIt is cheaper and easier to dig for oil in the moment, but because the oil companies generally aren't held liable for environmental damages, at least not relative to the amount of damage that they do (I'm looking at you BP Deep Water Horizon damage liability cap), the true total cost is ignored. There are other alternatives that may cost more in the immediate future, but not in the entire future. However, corporations are rewarded for quarterly/annual profit targets, so they only think/act that much in the future.\n\nI suspect many of the comments here are from paid representatives of the oil companies (assuming OP isn't one as well). Keep that in mind as you read through the comments.",
"I am against the Keystone pipeline, as [TransCanada](_URL_0_) and the Republican congress seem like they are not responsible enough to handle such a task and be truthful about the environmental risks.",
"Its not just environmentalists , but economists too. That oil isn't going anywhere but here, as it is cost prohibitive to sell overseas. A pipeline changes that, and you end up paying more for oil and gas while that piped oil is shipped and sold to other countries i.e. china",
"Also by rejecting the pipeline we are further sending a message that says, we are tired of being so reliant on non-renewable resources such as oil. ",
" > That oil is going to be transported one way or another.\n\nMaybe. Oil is extracted only if it is profitable. Profitability includes the cost to transport. It's reasonable to assume that if Keystone XL exists, the cost of transporting the oil is reduced, making it economically viable to extract _more_ oil from the region. Extracting more oil will also make the price of oil fall.\n\nSome of the people opposed don't want to see more oil extraction in that area due to environmental damage.\n\nSome people don't want to see the price of oil fall, as it encourages more consumption.",
"It's not about which is the safest to transport, it's about getting ourselves off of fossil fuels and using non-destructive, environmentally friendly forms of energy. Building a pipeline is the opposite of the direction we want to go in.",
"Environmentalist here. Maybe not a rabid one, but still. I see all new money, effort and risk put into further oil development and transport as steps in the wrong direction. I understand that the days of the fossil fuel economy are far from over, but wish that (I'm Canadian) we were putting more money into clean tech instead of pushing for the most rapid exploitation of our oil reserves.\n\nWe read every day about how critical it is to take action on climate and yet oil consumption is still ridiculously high. Now we need more efficient ways of getting oil to market? I say fuck that.",
"A lot of people are saying \"if the pipeline ruptures, it will create a huge spill in comparison to a truck overturning.\"\n\nWhile this may be true, it ignores the environmental damage that thousands of trucks or very large ships do *just by moving*. You burn a lot of fuel to transport oil over land or over sea, you wear out roads and tires and vehicles, and you have to involve a lot more people. Once the pipeline is built, it gets the oil to its destination much more efficiently. The question is what's worse: one major pipeline spill that goes undetected for too long (or many small leaks that aren't fixed), or thousands of vehicles driving thousands of miles carrying tens of thousands of pounds of fuel.",
"Welp, only read 15 comments... already a huge cock fight in here.\n\nI came in to read about the legit reasons, and got greeted with arguing... \n\nthanks reddit.",
" > That oil is going to be transported one way or another. \n\nThis is something that keeps getting repeated by proponents of the pipeline, but it doesn't really stand up to scrutiny. Transporting the oil using means other than a pipeline is dramatically more expensive. Given how much oil prices have crashed recently, this added expense may make it economically infeasible to extract that oil. ",
"In addition to all the valid point people have raised, I think it is more of a ideological opposition for a lot of people. We need to stop investing resources in things we know are destroying the planet.",
"For me, all the pipelines are great if we are 100% planning to take all of the Canadian oil sands (or tar sands) oil out of the ground. These pipelines will enable a MASSIVE increase in the size and scale of the oilsands operations. Canadian regulation of the oil sands is relatively poor (depending on who you ask) and regardless of what side of the environmental debate you're on, we could be doing better.\n\nI'm Canadian, have a masters degree in engineering in a related field, and I absolutely feel that we need to sort out our longterm resource development planning to account for climate change (after years of Conservative government, this is decimated) and to improve oversight before we consider approving all these pipelines (Keystone, Northern Gateway, Energy East etc)",
"_URL_1_\n\nRead about the Mayflower, Arkansas oil spill in 2013. It's considered a small example of what could happen. \n\nHere's an excerpt:\n\"Whether it's the proposed Keystone XL pipeline, or ... (the) mess in Arkansas, Americans are realizing that transporting large amounts of this corrosive and polluting fuel is a bad deal for American taxpayers and for our environment.\"\n\nThey literally just finished another round in the courts in August. Exxon fought hard to skimp on their responsibilities. It's been 2.5 years and the decision just came down in August they do indeed owe Arkansas $5 million. \n\n_URL_0_\n\nThe mess was so bad, you could smell the oil while driving down the interstate. Exxon still claims it was contained and never hit area creaks or ponds. Bullshit. Citizens had to wade through water with their cameras to prove them wrong. ",
"The potential magnitude of disaster when you have that much oil in one place at one time gives me pause. It's like when people say \"why don't we put all our nuclear waste on a rocket and fly it into the sun?\" Well, great, unless it explodes on the launchpad. \n\nSecond is the obvious potential for environmental impact. The pipeline was originally designed to run through the Sandhills region of Nebraska, which is a protected and fragile wetlands region. It also runs near many significant aquifers. No system is perfect, and the Keystone pipeline is projected by prominent ecologists to have 91 major spills over the course of a 50 year lifespan (this is calculated by counting the number of spill incidents per 1600 miles of pipeline per year of the first 1 year phase of the Keystone pipeline project, of which there were 11 minor and one major spills). TransCanada estimated the number of major incidents over a 50 year lifespan to be closer to 11 but this is a suspect number for a variety of reasons, primarily because TransCanada \"arbitrarily and improperly\" adjusted spill factor calculations to get a more conservative number. \n\nBasically, the pipeline is too close to important environmentally fragile areas and there is a mathematical certainty of major spill incidents which would have a major and irreversible impact on wildlife, the environment and our own drinking water. \n\nIt also crosses a major seismic zone. Fun fun. \n\nNext, there are political conflicts of interest that make the raison d'etre of the pipeline politically suspect. The State Department commissioned an environmental impact study in 2012 which was undertaken by a company called Environmental Resources Management. Turns out ERM had done previous contract work for...wait for it...TransCanada. DoS tried to hide this but failed. \n\nFourth, I'm essentially suspicious of any project that has the appearance of being a bespoke item bought and paid for by the energy industry. Too much money changed hands for this not to be dirty and I feel like we deserve a little better than energy projects that are the product of regulatory capture. I'm pretty fucking tired of having our economy directed behind closed doors by energy industry lobbyists. I feel when I talk about KXL like I live in fucking Russia. This is a second rate, second-world project and we don't need that shit. \n\nFinally, this project will ultimately discourage us from pursuing cleaner energy projects. We need to be finding an alternative to fossil fuels and building a mondo oil pipeline commits us to using more oil for the foreseeable future. Climate change is already a huge challenge and committing us to higher carbon emissions by enabling us to feed the need for oil is like saying \"man, I gotta lose some weight, this is out of control\" and then installing a soft serve dispenser in your kitchen. we need to be out of the oil producing business and KXL isn't helping us. \n\n ",
"The only people who really stand to benefit are oil industry executives who have a lot of power over Canadian and US politicians. New development should favor renewables ",
"Let's see, as Americans we're assuming a real environmental and societal risk to allow Canadian companies to ship filthy crude cheaply to Gulf Coast terminals enjoying special tax breaks since Katrina, to sell the oil at a higher profit to China where it will be burned with little environmental oversight. Not seeing the upside for anybody who isn't a TransCanada exec or major stockholder. ",
"Actually one reason is that without a pipeline, the oil may NOT be valuable enough to extract"
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"https://en.m.wikipedia.org/wiki/2013_Mayflower_oil_spill"
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4ibqoz | who owns the land? | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/4ibqoz/eli5_who_owns_the_land/ | {
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"When there was undiscovered land you could claim it, but your country of origin would likely have claim jurisdiction over you and your new land (so instead of \"claiming the country of Alek-istan\", I would claim territory that on the map would be part of my home country, although I own it (and just pay my king taxes). \n\nThis basic concept would play out today for Elon Musk, only the major world powers signed treaties back in the 60s that prevents people from claiming land in space, so his country of origin would simply force him to NOT claim land. ",
"Part of it really is whoever legally claims it first, assuming it wasn't already within the jurisdiction of some form of local government. If you wanted to, you could go to a remote part of the world, build a house, and claim that as your land, and nobody could stop you(assuming it isn't someplace protected by global wildlife/environment protection things).\n\nFurthermore, I'm pretty sure global governments agreed that planetary colonies wouldn't be owned by a single person. Could be wrong, though."
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6negdq | negative zero | In programming, a float or a double value can take a positive or a negative zero.
What is this number and why are the two separated in programming? | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/6negdq/eli5_negative_zero/ | {
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"When you're dealing with floating point numbers, you have to work around the fact that the numbers aren't going to be exact and will have rounding issues. Negative zero helps address some of those issues. Negative zero means that the number it's supposed to be is small enough that it just rounds to zero but is actually less than zero. ",
"It can happen when a very small negative value is rounded to zero, called *underflow*. \n\nFor example, let's say the smallest number your floating point can represent is 0.0000001. 0.0000001 / 100 is going to be rounded to 0.0, -0.0000001 is going to be rounded to -0.0. Remember, floating point numbers are just approximations of real world values. 0.0 doesn't mean 0, it means 0.0 is the closest value to my measurement.\n\nFloat point arithmetic does this for two reasons. First, it is easier. There is a separate sign bit for tracking positive vs. negative, and there is no particular reason to mess with it if a negative value rounds to zero. Second, there are a small handful of situations where know you are dealing with a small negative value can make a difference."
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3obhn3 | why dont we see more movies that actually show the other side of the war? (for example, the imperial army in ww2?) | First of all, I'm Australian and I understand that we (and americans, ect) will always prefer to watch movies about our side in wars, But why haven't we seen a movie about the Imperial Army yet? surely that would be fairly interesting right?
we always seem to ONLY see the Allies and learn hardly anything about the enemy we were fighting.
Is there a reason there isn't big blockbusters that focus on both sides?
EDIT: also, (Obviously I don't mean movies focusing on the Horrible war crimes committed and what not) | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/3obhn3/eli5_why_dont_we_see_more_movies_that_actually/ | {
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"Usually people make movies about the winners, it's easier to get an audience where the protagonist win. Or at least go down fighting for a worthy cause. \nBut there are movies about both sides.\n[Waterloo](_URL_1_) and [Gettysburg](_URL_0_) both spring immediately to mind. \nFor World War 2, the Germans really don't like to put anything WW2 related in their media for obvious reasons. The Italians... should be embarrassed about their war performance, so that's out. \nThe Japanese on the other hand can and do make WW2 films about their side. \nThey just aren't exported much since not many people liked what Japan did in WW2. \nLook up [Yamato](_URL_2_) for an interesting one. It's like Titanic with a massive battleship for the boat and Americans for the ice burg.",
"It's because you probably only know the film industry of the US and the industry of your own country. Im german and there are alot of german movies about \"our side\" in WW II, but you dont know them.",
"Because companies don't want to take risks.\n\nChances are, people in Allied Power countries won't like movies sympathizing with the Imperial Army, and might prove a box-office flop.",
"Most films depicting Japan in the war cover what it was like for the civilians (see Grave of the Fireflies (like, go see it, it's a pretty good movie)). The war has not been popular in hindsight, and history has not been good to the Imperial Japanese Army. For the Japanese the ideas of reconstruction and what war did to them is more important than the war itself, which is why we see movies like Godzilla instead of historical dramas. Likewise the controversy behind Japan's actions during the war make for very subjective views on history. Movies like Ip Man cover the Japanese occupation of mainland china from a Chinese perspective (and it's widely recognized as a pretty inaccurate film), but China and Japan have two *very* different accounts of the war (and no Hollywood production want's to risk pissing off either market) and both countries refuse to acknowledge the other one's account of events (Seriously, rape of Nanjing is still a very dicey political issue). \n\nThere was a blockbuster that focused on both sides though. Tora! Tora! Tora! is one of the most respected WW2 films and it does a pretty decent job of portraying both sides in the lead up to the Japanese bombing of Pearl Harbor. \n\nAs to the Germans, the Nazi's are one of the rare moments in history where people can outright be called \"bad guys.\" While the average German soldiers were just doing his job, any movie about the German perspective is heavily bogged down in the actions of German command. For this reason, most films showing their perspective are morality plays about the Holocaust.\n\nLastly, the Russians. Yeah they were \"allies\" but they got the short end of the stick from a western (really American) perspective because of two words: Cold War. US has had a vested interest in not painting the Russians too heroically and in the current political environment they don't really have an incentive to start. It's a real shame because Russia's drama in the war would make for some fantastic films, but until world politics iron out, we're gonna see a lot more Omaha beach before we see the battle of Kursk. \n\nEdit: grammar"
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62xxyu | what stocks are | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/62xxyu/eli5_what_stocks_are/ | {
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"Stocks are a method for investing in a publicly traded company. It is literally a (now electronic) record that represents a percentage ownership in a company. For example if a company has issued 100,000 shares and you buy 1,000 you will own 1% of that company. \n\nAs far as getting started, by asking that question it indicates that you should do a lot more research before you get started. \n\nIn short, you register with a broker, deposit money in a brokerage account, and pay the broker to buy, sell, and hold stocks on your behalf for fees.\n\n",
"A share is a piece of a company that you can buy. Stocks are just all the shares without regard for which company they belong to.\n\nYou can buy a share of a company and sell it later. That's the primary thing most people think about when they're playing the stock market. If that share's value goes up, you can turn a profit by buying it when it's cheap and selling it when it's expensive (\"buy low, sell high\"). Unfortunately, you don't know if a stock will go up or down, so you're playing a bit of a guessing game. Shares rise in value if the company either did well in the last fiscal quarter (in the last few months) or is predicted to do well in the next fiscal quarter (in the next few months).\n\nThere are tons of other things you can buy and sell that aren't stocks on the stock market, and different ways of buying and selling everything, but I'm just giving the very basics here.\n\nIf you want to know how to get started, you should look it up in /r/personalfinance or similar. Someone has probably already asked how to get started, so you can just look for that thread.",
"It's like this.\n\nI make Widgets. Widgets are useful, and popular, people like to buy them. \n\nI could keep toodling along, making a few widgets and selling them here or there. But I think a lot of people would buy widgets, and I could make a lot of money that way. \n\nThe problem is, I don't HAVE a lot of money. \n\nSo, in the simplest possible way of doing things, I get investors- I borrow money from my friends, and in exchange, they own part of my company- if they own 5% of my company, and i make $20,000, they would get $1000. \n\nOk. But that's a hassle. Maybe my friends don't have money, maybe I don't have friends. \n\nSo I offer the chance to EVERYONE to buy a piece of my company. This is a stock. You buy a fraction of Widget, Inc. This gives Widget, Inc. money, which we can use to increase the number of widgets we make. Theoretically, we make more Widgets, sell more widgets, I make more money, and we split that up among everybody . So you bought my stock for $1, now your stock is worth $1.10, you have more money, we're all happy. \n\nThe \"Inc\" is short for \"incorporated.\" If you want to sell stock, you need to be a corporation. There's various laws involved with it, but the big benefit is this: If I own an incorporated company, the COMPANY can go broke, but I cannot. So suppose I own my creditors $10,000 and the company only has $1. I lose the company. They can come and take the computers, and chairs, and staplers.\n\nBut they can't come to my house and take my stuff. I can only lose what I put into the corporation. \n\nStocks started out, and at root still are, just ways for companies to raise money and distribute risk. If I buy a dollar of stock, I can only lose a dollar. If I sink ten thosuand dollars into my friends business, I can lose ALL of that. \n\nBut what people quickly realized is that you can make a SECONDARY market out of buying and selling stocks themselves. \n\nSo, for example. You have your 1 stock of Widget inc. It currently has a face value of $1.10. However, things are going good! We can expect Widget Inc to make MORE money in the future! So someone comes along and offers to buy that stock for $1.50. They're essentially saying \"I'll give you more than the face value of that stock right now, because I think it will be worth more in the future.\" They expect that someday, it will be worth perhaps $2.\n\nSo this creates its own, separate market of buying and selling stock. Apple comes out with a hit new product! They're going to sell a lot of them, they'll make money, their stock will have more value, so people buy and sell it for more money. \n\nThere's also, in the same area, lots of similar items. For example, Treasury bills (T-bills) are sort of a stock in the United States. You pay $100 to the government today, and they'll pay you say, $150 in ten years. The benefit is the United States is very stable, very wealthy, so it's very, very likely you'll collect that extra money. \n\nThe funny thing with things like that, is that one of the most valuable assets is STABILITY. Say you're a rich guy in Somalia. Somalia is a very unstable country. Anything could happen. But you want to keep your money safe. \n\nYou may buy a $150 dollar T-bill for $151 dollars. Why? Because you're absolutely SURE you're getting that $150 dollars. The extra money is worth it to have value that you're positive about receiving. \n\nYou can also do this with commodities. Take wheat. You can say \"I'll pay you $1.50 now for a bushel of wheat at harvest time.\" You're betting that at harvest time, wheat will sell for $1.60 a bushel, and you'll make money. But what if there is a HUGE crop? Wheat might be $1.20 a bushel, and you lose money. \n\nAnd so on and so forth. \n\nGetting into buying stocks?\n\nDon't. The big people have huge software and tons of experts making moment by moment calculations. \n\nIf you're sure you want to try? There are, I believe, apps that let you \"test\" yourself. IE, you say \"ok, I would've bought 10 shares of apple today\" and it tells you how well you would've done. Use those for a while. \n\nLook for small companies about to get bigger. They sell a useful gadget or program. Perhaps they're likely to be acquired by a bigger company- in that case, your 100 shares of Widget at $1.10 often become 100 shares of apple at $40.\n\nGo small, talk to experts, never risk more than you can afford. "
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3nxkny | if we have a molten core in the earth made up of super heated magma, how does the solid iron core stay solid without just melting and joining the surrounding magma | as above. | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/3nxkny/eli5_if_we_have_a_molten_core_in_the_earth_made/ | {
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fnjmgi | why rna based viruses mutate faster than dna based virus ? | Notice i have a vague "very vague" understanding of how a cell replicates using DNA ! i also have no idea what is the difference between RNA and DNA. I am sure it's a super complex thing to explain so Super thanks in advance ! | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/fnjmgi/eli5_why_rna_based_viruses_mutate_faster_than_dna/ | {
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"Poor quality control.\n\nDNA has mechanisms to prevent copying errors and/or destroy defective copies. RNA, particularly in a virus which isn't completely \"alive\" just doesn't have the complexity to support these mechanisms.",
"Well let's start with some background then move towards your question. I trust you understand DNA is a biochemical code. It's made of these four bases or nucleotides, ATGC. A DNA code can be something like AGTGGGCTCAGAATC for example. In our body, an large protein complex can be recruited to this DNA and it can start reading it. Each base has a complementary base it binds to, A to T and C to G. This complex starts reading the code and creating a new string of code to complement it. But it makes RNA, which is a little different in that the sugar (which is part of the nucleotide) is ribose as opposed to deoxyribose. So it had an extra oxygen. Also, there is no RNA T base, instead a U. So for DNA sequence AGTCGCA the reverse complement would be UGCGACU in RNA. This RNA can then get processed a bit, modified a bit, edited and spliced to remove some parts of the sequence, etc. Then a large molecular machine called the ribosome gets a hold of this RNA string and reads it, this time making a string in a completely different language. The first process was transcription, now it's translation. For each 3 bases, there is a tRNA molecule that can bind (it has the complement) and on the other side it has a specific amino acid. More than one sequence per amino acid, but let's not get into that. Anyway, so now for each three bases or a codon, an amino acid is brought in and is joined to the growing string of amino acids, the polypeptide chain. This is a protein, it can be helped by some other proteins along with just laws of Chemistry and physics to fold onto itself and have a specific shape. Then it goes on to do its function after being sent somewhere specific in the cell.\n\nSo now you know the difference generally. DNA is double stranded, and made of ATGC and functions as a stable storage of information and is very.... Very long in humans. RNA has AUGC and functions as an intermediate message linking information to product, in humans its single stranded, and it has dozens of types and maaaaany other functions you shouldn't worry about. This RNA I describe is mRNA or messenger RNA, there others that can act like enzymes for example, or or or.\n\nViruses either have single Strand of RNA (ss) inside, double stranded RNA (ds), ssDNA, and dsDNA. A virus does not have the capacity to live (metabolically) or reproduce on its own. It needs to infect some other complex cell and hijack its systems to make more of itself. Some viruses bring some of their own proteins with them that are crucial since our cells don't have them, others Code for proteins they need in their own genome and use our machines to make these proteins that can then help the virus reproduce. As DNA is the storage of information, our cells have maaany ways to proof read it when it's getting copied (when the cell divides) and also repair the issue when it's wrong, and if the damage is too severe, kill the cell to protect the body. We don't care much for RNA, if there's a mistake, the protein product will be defective and it will be destroyed with other mechanisms. We also don't replicate RNA, so we really don't care.\n\nSo now when a virus with DNA infects us and tries to replicate its DNA, the enzyme that does it has proofreading ability and the cell can correct mistakes if they happen. For RNA, the enzyme for replication comes from the virus, since we don't do RNA replication. And this is one clumsy enzyme, it works fast and makes many errors, it cannot proofread and we can't fix errors for the virus. And this enzyme is coded by the virus genome, so errors in the genome can also cause errors in the enzyme and so the problems are compounded. I won't even get into the concept of reverse transcription where it makes DNA from the RNA and then goes from there adding another step of errors. The other issue with RNA is that, like I said, some viruses have ssRNA and \"many RNA replicative intermediates do not have extensive double-stranded structures, precluding the operation of mismatch repair systems that are effective on double-stranded DNA\" (excerpt from paper). So this high error rate and low quality control makes mutation rate so high. \n\nI hope this answer your question.",
"RNA viruses use a different protein for replication from DNA viruses. The DNA one is more accurate but slower, like someone proofreading an essay. The RNA one is much faster but less accurate (mutates more), like the student who writes their essay 2 hours before it's due because they thought binging episodes of Breaking Bad was a better idea.",
"In very simple terms:\n\nDNA is double-stranded and each piece of a strand connects to exactly one other known piece from the other strand. When damage occurs and a piece is destroyed, the DNA can look at the other strand to see what exactly was destroyed and replace it accordingly.\n\nRNA though, is single-stranded, so whenever damage occurs, it has nothing to base the replacement on, so it just replaces it with a \"random\" piece, aka it mutates.",
"RNA is much simpler than DNA. I can give you a simple explanation that you will understand. But there's lots of information that you might want to know related to your question. So I'll add in some ELI5 info on it.\n\nThink of a ball of yarn called a chromosome. All that yarn is just one long string of DNA (typically about 3 meters). Therefore, a chromosome is just your DNA balled up with some protein packaging protecting it.\n\nThere are 46 chromosomes in the nucleus every single cell of your body (few exceptions). That means 46 balled up strings of DNA.\n\nThe totality of all 46 strings of DNA together is known as your genome. Your genome is the blueprint of your entire body. Therefore, every nucleus of every cell in your body contains the blueprint for your entire body.\n\nIf I was in the future, and wanted to clone your body. A futuristic machine might require your genome as input. All I would need is any single cell from your body. Extract your genome (the DNA from all 46 chromosomes in the cell's nucleus), and put it in the machine. The machine will be able to construct your body from the information in your genome.\n\nEach strand of DNA is made up of sections, known as genes. Like say you tied different colored segments of yarn end to end to make up one long string of yarn. Each of those colored segments would be a gene. Genes vary in different lengths. Each gene contains information for constructing specific parts of your body.\n\nAside from facilitating cell division, DNA doesn't normally leave a cell's nucleus. Instead, copies of its genes are made. These copies are known as, RNA.\n\nRNA is produced within the nucleus of each cell. RNA is a copy of a gene (specified segment of your DNA). Although the copy is basically identical in structure to the gene, it has a different composition. For example, a cotton t-shirt or a nylon t-shirt. Both can be the exact same t-shirt in shape and size. Just made of different material.\n\nWithin every cell are manufacturing plants called, ribosomes. The RNA leaves the nucleus, and enters a ribosome. The ribosome reads the information of the RNA and collects amino acids that are floating around. It will then combine the correct amino acids in the correct order to construct the correct protein according to the information from the RNA.\n\nTo answer your question. RNA is significantly simpler than DNA. It's typically a copy of a DNA segment (gene), but made from different substances. A strand of RNA, however can exist independently. RNA is often considered the first lifeform. Scientists are working hard on testing RNA in very controlled conditions. They've had some amazing breakthroughs in getting RNA to behave in certain ways. However, they still haven't managed to get it to naturally evolve into a more complex life form.\n\nJust briefly on viruses. A virus is more like an inanimate nano-apparatus. It's considerably smaller than a cell. Often not even considered a lifeform because it can't do anything on its own. It's more like a tiny box containing DNA or RNA. In fact, there are over ten times as many viruses than not just all complete lifeforms, but all cells on the planet."
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86m65f | if you have two objects moving at the same speed, the one further away appears to be moving slower than the one which is closer. why? | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/86m65f/eli5if_you_have_two_objects_moving_at_the_same/ | {
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" > If you have two objects moving at the same speed, the one further away appears to be moving slower than the one which is closer. Why?\n\nGeometry. If you have a line sweep out an angle from a set point, the greater the distance along that line the greater the length of the arc produced. This means that the more distant the object the slower it moves across your field of view for a given speed.",
"They're covering a smaller distance across your eyeballs. Visual degrees per second is the factor here, not their linear speed.\n\nA baseball whizzes past at 100 mph and you can barely see it, because it's blown bast 180 degrees of your vision in a fraction of a second.\n\nThe moon is hauling ass through space at *2300* mph but appears to barely move because it's so far away that it's covering only a fraction of a degree of your visual field.",
"The name of this concept is called parallax. When you're in a car, things that are near you pass through your field of vision quickly. The mountain way in the distance doesn't seem to move, even though you're moving past it at the same rate of speed.\n\nThis also holds when other objects are moving and you are not (because there's no real difference between those two)",
"For the same reason that things further away look smaller.\n\nImagine you're looking at a building that's 100 meters wide, and 100 meters away from you. It will take up most of your field of vision. Now imagine that same building, but it's 200 meters away from you. It will appear to be about half as big.\n\nNow, imagine you see someone standing at one side of that building throw a ball to the other side. If they throw it really fast, it will take about 2 seconds to get from one side to the other.\n\nSo, if you're standing 100 meters away from the flying ball, it will appear to move all the way from one side of your field of vision to the other side in 2 seconds. If you're standing 200 meters away, the apparent distance it moves will be smaller, but the amount of time it takes to move that distance will be the same. So it appears to move more slowly.",
"Things that travel the same speed go the same distance in the same amount of time.\n\nWhen things are far away, very large distances look small.\n\nSo even though both cars are going the same distance in the same time, the one farther away doesn't look like it moved very much which makes it seem slower.",
"Speed = Distance / Time\n\nIn simpler terms, a car going fast will travel further in 10 minutes than a car going slow. Or you could say that if a car travels a small distance and takes a lot of time to do so, then it's going slow.\n\nWhen things are further away, they obviously seem smaller. In other words, *distances* seem smaller the further they are from you. And if distance seems smaller, then according to the above equation, so does speed. Seemingly smaller distances makes speeds seem smaller too.",
"Parallax effect. Objects closer to you fill more of your visual field so you are more sensitive to their motion than objects farther away. It also works with relative size regardless of distance. A freight train moving at 20 miles an hour, looks a lot slower than a rabbit running at 20 miles an hour. Ironically this is the opposite of the parallax effect, where the smaller rabbit seems faster. But imagine a far away freight train, the size of the rabbit, appearing to move as quickly across your visual field, your brain would work out that it was moving very fast. \n\nFinally the vector of the motion matters. The closer you are to an object in motion, the more likely it's going to be moving side to side from your view point, rather than head on (cause you move out of the way) But looking at an object moving directly towards you, it's harder to judge it's speed and distance because it appears to be slowly growing, rather than moving along a vector. \n\nSo in summary, objects appear slower to us when they dominate less of our visual field, When their movement across our visual field is slower (coming right at you and growing in size rather than moving left/right/up/down), and our brains estimation of their size and distance also impacts our perception of how fast it's moving. ",
"Right in front of your eyes, a foot of \"space\" takes up about a foot of \"visual space.\"\n\nIn just the same way that objects look smaller from further away, space itself appears smaller (though of course you can't see it) from further away. So, a foot of space that's a hundred feet away in front of you looks tiny, and an object crossing that space looks like it has barely moved.\n\nThus, if an object is right in front of your eyes, it will appear to have moved further in the same amount of time than an object that's far away.\n\nAt least that's about how I'd explain it if you were actually five :)"
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3iqwha | why forcing women to take an ultrasound before aborting their fetus is wrong. | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/3iqwha/eli5_why_forcing_women_to_take_an_ultrasound/ | {
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"Do you have to look at the inside of a zit before you pop it? Do you have to look at the tapeworm inside your bowels before you have it removed? Do you have to look at a tumor before you are allowed to have it taken out? Forcing someone to look at the fetus they've already decided to get rid of isn't even slightly medically necessary. It's a mind game tactic intended to control women's reproductive rights and sexual identity. ",
"Knowing you should do something and being able to easily do it are two different things. You might know that euthanizing your dog is the right thing to do because they're old and in pain, but that doesn't mean you want to be the one to give it the shot. Or to make it more analogous, you wouldn't want to have to see a bunch of pictures of other dead dogs before the vet really accepted your decision.\n\nSimilarly, making you look at pictures of the fetus will most likely cause you to feel uncomfortable and bring unnecessary doubt and trauma into the picture, which is the intent behind the law. People in favor of the law would say \"anything is worth it if it prevents an abortion\" but people who oppose it would say that \"the decision should be based on rationality and thought out discussion, not knee-jerk emotional reactions.\" The opposition would also argue that people who decide to go through with the operation anyway, which is most people, will be unnecessarily traumatized by having to see the pictures.\n\nWith cigarettes, the pictures are fine because most people don't think there's any legitimate reason for anyone to smoke. Sure, you can if you want to, but if everyone stopped smoking tomorrow then no one would really care except the tobacco industry. Same with drunk driving. No one really thinks there's a legitimate reason to drive drunk.\n\nThe \"legitimate reason\" thing comes into play with abortion. The people who like the law probably think there's no legitimate reason for anyone to ever get an abortion so it should always be a huge hassle to get the abortion and you should have to be second guessed as much as possible. If you think there are legitimate reasons someone might want an abortion, then you probably want them to make an informed, rational decision and not second guess it at every turn.",
"FYI- There's a good discussion on this going on here: _URL_0_"
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6beca2 | why do we generally depict aliens as tall, scrawny people with large dark eyes and a rounded head? | Google 'ayy lmao' and you'll have a picture to match the description. | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/6beca2/eli5why_do_we_generally_depict_aliens_as_tall/ | {
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"Whitley Streiber's *Communion*\n\nThat is the only reason, although of course True Believers will have a very different explanation... ",
"It stems from an \"eyewitness\" report from two claimed abductees, who described their abductors under hypnosis in terms similar to what we think of as the greys (the slang name for the alien you're describing). Critics pointed out that the description closely matched a depiction of aliens on a show called Outer Limits and that they were just imagining the alien under hypnosis. Bonus fact for you, aliens are associated with rectal probes because reports of probing aliens spiked up shortly after Reagan went on national television to advocate for prostate exams. Apparently the aliens took Reagan's advice."
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jmg9g | foreign accent syndrome
(if there is an explanation) | explainlikeimfive | http://www.reddit.com/r/explainlikeimfive/comments/jmg9g/eli5_foreign_accent_syndrome_if_there_is_an/ | {
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" > (if there is an explanation)\n\nThere most certainly is!\n\nThe name \"Foreign Accent Syndrome\" is a bit of a misnomer (a mistaken name). If you listen to a person with FAS for only a minute or so, it can indeed sound like they suddenly acquired an accent. But listen a bit longer, and you can start to tell that they don't have an accent, but a speech impairment. \n\nThe particular accent varies from case to case, but I remember hearing of a British woman sounding \"French,\" or the original case, which was a Swedish woman who sounded \"German.\"\n\nWhat all cases of FAS have in common is this: the person receives some kind of head trauma--falling and hitting their head, suffering a minor stroke that they think is just a headache, and *then* the person gets an accent.\n\nWhat seems to be happening is not that they're switching to a new accent. The current theory is that they've had a tiny amount of brain damage that only affects how they talk. It's likely--especially because there are no known cases of a Deaf person suffering from FAS--that this brain damage affects some part of the brain that controls how people move their mouths and tongues to produce sounds.\n\nFor some people with FAS, it seems to be the sounds themselves (some people have a \"Boston\" accent, but they really just lost the ability to make \"r\"s). For others, it seems to be the normal rhythm of speech or the coordination of making the sounds of words in the proper order that is affected. And for some people, only longer words are affected; their shorter words might not be affected at all.\n\n[Here's a short documentary on it.](_URL_0_)",
"[There's a case](_URL_0_) of Czech bike racer who lived in England, but spoke very bad English. When he woke up in an ambulance after suffering head injury, he could suddenly speak fluent English. As he recovered, he gradually forgot it.",
" > (if there is an explanation)\n\nThere most certainly is!\n\nThe name \"Foreign Accent Syndrome\" is a bit of a misnomer (a mistaken name). If you listen to a person with FAS for only a minute or so, it can indeed sound like they suddenly acquired an accent. But listen a bit longer, and you can start to tell that they don't have an accent, but a speech impairment. \n\nThe particular accent varies from case to case, but I remember hearing of a British woman sounding \"French,\" or the original case, which was a Swedish woman who sounded \"German.\"\n\nWhat all cases of FAS have in common is this: the person receives some kind of head trauma--falling and hitting their head, suffering a minor stroke that they think is just a headache, and *then* the person gets an accent.\n\nWhat seems to be happening is not that they're switching to a new accent. The current theory is that they've had a tiny amount of brain damage that only affects how they talk. It's likely--especially because there are no known cases of a Deaf person suffering from FAS--that this brain damage affects some part of the brain that controls how people move their mouths and tongues to produce sounds.\n\nFor some people with FAS, it seems to be the sounds themselves (some people have a \"Boston\" accent, but they really just lost the ability to make \"r\"s). For others, it seems to be the normal rhythm of speech or the coordination of making the sounds of words in the proper order that is affected. And for some people, only longer words are affected; their shorter words might not be affected at all.\n\n[Here's a short documentary on it.](_URL_0_)",
"[There's a case](_URL_0_) of Czech bike racer who lived in England, but spoke very bad English. When he woke up in an ambulance after suffering head injury, he could suddenly speak fluent English. As he recovered, he gradually forgot it."
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1lq8b3 | why do some devices (cell phones, bluetooth devices, clock radios, etc.) only use small internal antennas and other devices (wireless routers, walkie talkies, televisions, etc) use bigger external antennas? | I have seen wireless routers that have no external antenna, one and as many as three antennas. What is the difference between these devices? Also I have a USB wireless adapter and a PCI wireless adapter; the USB seems to work just as well as the PCI one even though the USB does not have an external antenna. Please explain the differences. | explainlikeimfive | http://www.reddit.com/r/explainlikeimfive/comments/1lq8b3/eli5_why_do_some_devices_cell_phones_bluetooth/ | {
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"External wifi antennas can output more signal further.\n\nA wifi antenna in a phone simply has to detect and connect to a router. A wifi antenna in a router needs to broadcast a load of data and receive a load of data to possibly dozens of devices."
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d92mlm | if the earth's core produces geothermal energy which is a renewable resource - why aren't we harvesting this energy? | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/d92mlm/eli5_if_the_earths_core_produces_geothermal/ | {
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"We are - it's a growing energy resource. Historically, it was limited to areas near tectonic plate boundaries, but recent technology has changed that - and it's now growing more and more common.",
"We are where we can. Iceland has many geothermal power stations and it supplies a majority of their power needs (56.1%). IIRC they are also looking to build excess stations so that they can convert the excess power into something storable like electrolysis of water to create hydrogen fuel. Iceland is an ideal place for geothermal because of its volcanic proximity. \n\nIn Nova Scotia where I'm from we have far less but more every year. It's likely more efficient for us to capture wind energy and convert excess into \"earth batteries\" where energy can be stored until it's needed, either by heating liquid salt or pressurizing air to spin turbines.",
"We use geothermal energy all the time, for a lot of things. The entire country of Iceland uses geothermal energy for water heating. We've been doing it for thousands of years, too. Geothermal energy is usually best harvested around the Ring of Fire, because magma is very close to the surface and therefor more easily accessed.",
"We are. But it isn't as easy as you think. Also, the bedrock isn't equally warm, and actually few places are volcanically active.\n\nAlso to harvest this energy you need to drill deep wells.\n\nBut... if you want, you can buy a geoheat system for your house. My parents new home has one. Good and cheap.\n\nBut. Geo electricity isn't really that perfect. In a way it is fracking. You need to inject something that heats up and the recover it. Just geo heat has the issue of deep hols being drilled. In Finland we just drilled one, and clearly the ground wasn't happy about it. Plenty of strange unexpected isssues, but they got it done. (Then again they drilled in a city)."
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4751hi | why does bath salts / minerals make bath water feel hotter than normal? | I enjoy taking baths. I regularly use bubbles and have lately been getting into using bath salts. Normally filling the tub at the hottest temperature is just perfect! I've noticed that when I use salts, though, it is extremely hot (far too hot for me to handle).
I take baths often enough that the common thread really does seem to be the salts, not anything else. | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/4751hi/eli5_why_does_bath_salts_minerals_make_bath_water/ | {
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"I don't have any source for this, but I'm guessing it might have something to do with bath salts removing dead skin. Think of water touching a cut where a fresh skin layer is revealed - it feels like it burns. Maybe the salts removing a \"protective\" layer of dead skin causes it to feel a little hotter. Not technically temperature wise, but still. Just a guess.",
"Some may argue that salt water changes the boiling point so the water can get hotter, which is true, but I doubt a bath in 212*F (100*C) water is comfortable, let alone higher.\n\nIn reality, the amount of energy required to raise the temp of salt water is less than \"pure\" water, so your bath does not cool off as fast with salt in it. "
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v7vw7 | lagrangian points | I’ve done some research on it, but I don’t really understand what it is, and why they occur. Is it something to similar to geosynchronous orbit, or am I heading in the wrong direction? | explainlikeimfive | http://www.reddit.com/r/explainlikeimfive/comments/v7vw7/eli5_lagrangian_points/ | {
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"[its easiest to visualise using point 1](_URL_1_). If you think that there's two objects attracting each other (earth and sun) then there's going to be a point between the two where the gravitational pull from each is equal, so you are being pulled towards the sun with the same force as you are being pulled to the earth. That point is L1, where the forces balance each other. The other points are where other balances of forces occur. L2 is where the force of the object flying out into space is balanced by the gravity of the earth and the sun combined. L3 is opposite side of the sun, 180 degrees round the line of earth's orbit, so you only have the influence of the sun. L4 and L5 are a bit more complicated, but again they are just the points where some combination of forces balance out. [You can find asteroids in the L4 and L5](_URL_0_).",
"easiest explanation is , there are many forces at work in the universe some work against each other and the lagrangian points are the sweet spots where neither force has the upperhand"
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2lpy0n | what happens when someone dies will-less? | Like what happens to all their stuff? | explainlikeimfive | http://www.reddit.com/r/explainlikeimfive/comments/2lpy0n/eli5_what_happens_when_someone_dies_willless/ | {
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"Somebody who dies without a will is said to die \"intestate.\" After their debts are paid off, the decedent's estate (leftover stuff) will be given to relatives based on a formula which varies by state or country. Usually that means spouse and/or children, followed by other family members. If nobody is left, the assets will go to the government. \n\nEdit: the above answer is accurate in the US, and should also largely apply in other countries who trace their legal systems back to English common law (e.g., the Commonwealth Nations). I can't speak to other countries. "
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4en2vg | what is it called when one's foot suddenly bends to one side, causing the person to trip or suddenly fall down, and why does it happen? | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/4en2vg/eli5_what_is_it_called_when_ones_foot_suddenly/ | {
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"It's called \"rolling\" or \"spraining\" your ankle.\n\nYour ankle joint is a rounded rod pushing down on a cup. Normally, if you put weight straight down on the cup, it will stay still. However, if the cup is slightly tilted and you put weight down on it, it would push the cup to the side until it falls over!\n\nYour foot is the cup and your lower leg is the rod. If your foot steps on something uneven, it's possible that the ankle is not straight when you put weight on it, this will cause an imbalance and can cause someone to fall over."
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529tre | why, when you faint, your body covers you in a thin layer of sweat really fat? | I've fainted and passed out multiple times, and I get why you get tunnel vision and why you can't hear anything when you wake up.. but, if when you pass out from low blood pressure you feel really cold, then it makes no sense that you sweat, because that would cool you down even more.. right? | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/529tre/eli5_why_when_you_faint_your_body_covers_you_in_a/ | {
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"You're cold because you're losing heat... through your sweat\n\nWhy you sweat is a different question but it mostly has to do with your immune system reacting to your low blood pressure",
"While we're here. ELI5: Why DO you get tunnel vision and loss of hearing?",
"When you are stressed, your adrenaline levels increase. This can cause sweating. The body's response is not always \"logical\"."
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1mrrom | if i can see the moon and the sun in the middle of the day, does that mean that the other side of the world can't see either? | explainlikeimfive | http://www.reddit.com/r/explainlikeimfive/comments/1mrrom/eli5_if_i_can_see_the_moon_and_the_sun_in_the/ | {
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"Yes. [If the moon and sun are both on one side of the planet (as is the case with a new moon phase) then they are not going to be visible from the other](_URL_0_)\n\nEdit: Assuming you are on the equator or within a latitude which is heavily populated, not at the poles. With the other person on the far side of the planet so it is midnight there.\n\nPlease also note that the moon takes 28 days to orbit the earth and so will stay in essentially the same phase as shown on that image for a 24 hour period of longer as the earth rotates around.",
"Isn't the moon we sometimes see in the middle of the day a reflection?",
"\"if I can see the moon and the sun in the middle of the day, does that mean that the other side of the world can't see either?\" \n \nI need someone to explain this question to me like I'm 5.",
"I drew a picture ~~(sorry it's sideways)~~ : _URL_0_\n\nSo the earth is spherical, the shape of a soccer ball. If you're at \"X\" you can't see the sun, that'll make it night time but you also can't see the moon because the earth is in the way.\n\nThe earth will rotate and eventually X will come into the same position as \"Y\" and you will be able to see both.\n\nThe thing to remember is that the moon also rotates around the earth. Sometimes it will be between earth and the sun or in the middle.\nAnd other times it will be on the outside, when it's on the outside there will be a full moon at night. \n\nSo the earth rotates. The moon orbits (moves around the outside of) the earth and we both orbit the sun.\n\nEdit: image rotated",
"Playing around with [this cool little applet](_URL_0_) might give you some intuition about this. You can manipulate the moon's place in its orbit, as well as the Earth's rotation.\n\nThe dark hemisphere of the Earth is the part of the Earth that can't see the Sun, and in the applet on the lower right you can see if the moon is above the person's horizon, and if it is that means that they can see the moon!\n\nNotice that the closer together that the Sun and the moon are, the larger the cross section of the Earth that can't see either of them at the same time.",
"If I can see the moon and sun in the middle of the night...",
"We, people live on a giant ball called Earth. Yes it's a ball. It's simply so large we can't conceive Earth's roundness with our little eyes.\n\nPeople live all over the Earth's surface. Don't worry for people on the other side. They don't fall into the deep space, because what's you call the \"bottom\" is actually the Earth center which attracts everything by making things heavy and falling. So people on the other side have foot stuck on the ground just like you; for these people that's you who looks upside down.\n\nThat being said, the Earth turns around slowly. It takes one day to make a full turn on itself. That's cool because it allows you to see different parts of Space while the ground you're on is turning. When, the ground you're on is facing up the sun, then you can see it. Also the sky above you goes blue and all bright.\n\nWhen you can't see the sun anymore, then you're in the shade of Earth, and the sky air is not lighten anymore. That's night time now. Also you can see stars through the fully transparent air.\n\nAbout the Moon. It's a ball like the Earth which moves trough space. The moon is attracted by the Earth just like you. Luckily, it's got a lot of momentum so it doesn't fall, instead the gravity simply makes it turning forever. It takes 28 days for the moon to make a full turn around the Earth. \n\nDuring half a day, the ground you're on is facing up the moon. Then you can see the moon. It is far enough for not being in the shade of the Earth. So it is more or less lighten by the Sun, making nice shapes like a crescent. \n\nDuring like a half of a Moon month, the moon is in the same side that the sun, so you may see both the moon and the sun at the same time (but often the sky is too bright to see the pale amount of light coming from the moon). Of course, people on the other side of the world are sleeping at the same time. They don't see neither the Sun or the Moon.\n\nNote this little thing: It's not possible seeing a full moon at plain day. Because when the Moon is at the same side than sun, it is actually between the Earth and the Sun. From your point of view, the sun is behind the moon, so it can't obviously light the side of the moon you see at this time.\n",
"Given the way the question was posed and the amount of of people that upvoted it; this whole thread makes me feel smart. ",
"that depends on how you define \"other side of the world\" as in your question you have proposed 3 different other sides of the world. without knowing the relative positons of the sun moon and you in relation to the earth I can't tell you.\n\nI CAN tell you what the 3 other sides of the earth are as I see them. imagine a \"line\" bisecting the earth from you to the opposing side and a line from each the moon and sun going straight through the earth to the other side.\n\nthe people at these opposing sides can not see the sun or moon since they are on the opposite sides of \"each\"\n\nbut if say the sun is on the horizon on the east and the moon is on the horizon on the west then a person on YOUR opposite position COULD possibly see both or \"pretty close\" ie see the light maybe. depends on how high they are off the surface (mountain etc..)\n\nif the sun and moon are above your head then no someone on the other side will not be able to see them.",
"Yes. This is true for anything: if you can see it by looking up, someone on the opposite side of the earth can't see it, because the earth is in the way.",
"you just shrunk. you're on a basketball and somebody is beaming a flashlight at you. they're also holding a golf ball. \n\nnow, if you move to the opposite point on the basketball, would you be able to see the flashlight or golfball?",
"This is one that I think a 5 year-old would already understand. Obviously, if the sun and moon are both on one side of the Earth, then they wouldn't be visible on the other side.",
"Not fully. If both the sun and the moon were directly above you at the same time, then neither could possibly be seen from the other side. If, more commonly, the sun and the moon are both visible, say on opposite horizons, then half the world could only see the sun while the other half could only see the moon. It's hard to picture another part of the world seeing a sunrise the same time you would see a sunset, but this is the case. If you look up and see no moon after the sun set, then you can assume that both are seen somewhere else, but not necessarily both at the same time.",
"Again. Not to be a jerk. But hey when was the last time you could look through a solid sphere? ",
"In case no else has given this link, check this out: _URL_0_\n\nLet the animation play, spin the earth and move the moon manually, and watch to view of the moon change. You should get a pretty good idea of how everything works.",
"Think of it this way. The lunar calendar is pretty consistent around the world (+/- half a day for the opposite side). When it's a New Moon (i.e. no moon visible during the night), then the moon must be on the other side of the planet, which happens to be where the sun is.\n\nOf course, there are cases where you can see the moon on one horizon, you can see the sun on the other, and someone over either horizon can see one but not both.",
"Think of yourself as being on the moon. You can only see, at most, one half of a sphere (Earth) at any given time. Same with the Sun. Half is in light, half is in dark.",
"This used to happen when I was in Iraq. It would get ridiculously dark out. I always just assumed there was a sand storm in the air or something.\n\nTIL...",
"Actually, atmospheric refraction allows you to see the sun after it's already \"set\" (mathematically), and I'd assume the same for the moon. Therefore, just before apparent sunset, you should be able to see a full moon rising (barring orbital tilt) and the people at your antipodes should see a rising sun with a full moon setting.",
"Yes, that does mean that. If you are wondering, \"but I can see the moon every night,\" the answer is that the phenomenon you described only happens during or near a new moon. \n\nThe full moon is a result of the moon being far away from the sun, so a full moon is always high in the sky at midnight. The new moon is a result of the moon being near the sun, so the new moon is always high in the sky at noon, and completely invisible at midnight (you might see it around dawn or dusk). \n\nIf you are wondering why full moons are far from the sun and new moons are near the sun, imagine a room with a very bright light on one wall and you standing in the middle. I am walking around the room staring at you. If I stand near the light, you will see only my silhouette. I will appear black and featureless, because there is no light hitting my face. If I stand away from the light you will be able to see me clearly, because there is a bright light shining on my face. My back is in shadow, but my face (the part you see) is lit up. ",
"And don't forget, the \"dark\" side of the moon in this instance is the side facing us, because the sun is behind.\n\n\"There is no dark side of the moon. It's all dark, really.\"\n",
"The ignorant, mean-spirited replies to this question are the sad result of ELI5 being included in the main list. I miss the smaller, friendlier sub without all the 12 year old hormonal trolls.",
"Place your hand on the back of your head. Can you see it?",
"A full moon, by definition, is 180 degrees across the sky from the sun. A truly full moon, known as at opposition (opposite the sun in the sky), will rise at sunset and set at sunrise.\n\nWhen the moon is new or full, the Earth, moon and sun make a (nearly) straight line in three dimensional space. This is known as 'syzygy'. Cool word! Pronounce it \"sih-zih-gee\".\n\nWhen the moon is new or full, one might expect a solar or lunar eclipse to occur each month. The moon's orbit around Earth is tilted about five degrees relative to Earth's orbit around the sun, though, so it only happens when the planes intersect, and the line of intersection points toward the sun, generally a couple of times a year. And because of this, lunar and solar eclipses tend to happen together, about half a month apart. \n\nHow long does it take the moon to orbit the Earth, say from new to new moon? About a month. Where did you think the word 'month' comes from??? It takes about a \"moonth\".\n\nAs for eclipses... the sun is about 400 times farther from Earth than the moon. The sun also happens to be about 400 times bigger diameter than the moon. Therefore they appear to be about the same size in the sky (the Earth is about four times the moon's diameter, by the way). Because the orbits of the Earth about the sun, and the moon around the Earth, are both elliptical, distances vary a bit over time. Total solar eclipses only happen when the moon is relatively close to Earth, and the Earth/moon pair are relatively far from the sun. If the sun is relatively close, and the moon relatively far, so-called annular (\"ring shaped\") solar eclipses occur. The sun is mostly covered by the moon if on the path of annularity (in the center of the shadow path across the Earth), but a thin ring of sunlight is visible all around the edges of the moon at midpoint of the eclipse.\n\nThere's a total solar eclipse due to happen over the continental US in 2017, it will pass from the NW US toward the SE. I am very much looking forward to it. There will be another total solar eclipse over the US in 2045, passing very close to where I live. I doubt I'll make it that long, though. The path of totality of the 2017 eclipse will pass a few hours to the north or northeast of me, I hope to make it to see that one, though. :D ",
"As an aside, in 5th grade, one of my classmates asked this very question. My teacher never understood what was being asked even though seemingly the rest of the students did. I remember it was rephrased a number of times by different students, but she never ended up understanding the question. We never knew the answer... until now. ",
"This could also be a /r/showerthoughts",
"ITT: A lot of people making fun of someone trying to learn. When did this Sub get so toxic? Used to be quite friendly."
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98la7o | british royal family? | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/98la7o/eli5_british_royal_family/ | {
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"In theory, the Queen holds a great deal of power. She appoints the Prime Minister, the members of the House of Lords, and many other important people. All new laws must be approved by her.\n\nIn practice, she is a figurehead. The Prime Minister must be the person who is supported by a majority of the House of Commons, and her other powers are exercised on the \"advice\" of the Prime Minister. She does have influence, not least because she meets with the Prime Minister once a week.\n\nThe question of how she is paid is tricky. In theory, she receives a grant from the government in return for giving up the income from the Crown Estate - land owned by the monarchy. The government makes a profit on that deal, since the grant is a fraction of the Crown Estate's income. But if we had no monarchy, that land would most likely be owned by the government, and the government would get to keep all the income. (Or, more cynically, the government would have sold off the land to their friends decades ago)."
]
} | []
| []
| [
[]
]
|
||
4s1rxx | how does eating more portions throughout the day make you lose weight more than just eating less, (ie. one meal)? | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/4s1rxx/eli5_how_does_eating_more_portions_throughout_the/ | {
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"text": [
"The idea is that you do end up eating less. Eating smaller meals more frequently keeps you consistently satisfied, so you don't get real hungry and then have a huge 1000 Cal lunch. ",
"If you eat 5 meals totaling 2000 calories in one day and then eat 1 meal equaling 2000 calories the next day. Both days are the same in your bodies perspective. However, it isn't to your mind. If you waited til dinner to eat all your daily calories your mind will be going crazy with hunger. You'll sit down and think, \"EAT ALL THE FOOD!!!!!\" This puts you at risk of overeating your calorie intake, because it takes time for your stomach to tell you that you're full. So instead of 2000 calories you eat 2500 calories because you inhaled your food at dinner and then thought, \"Man, that cream pie looks pretty tasty.\" if you eat 3 meals, by dinner your brain is thinking, \"Oh, dinner, this looks good.\" You eat it slowly and by the time your done you think, \"Wooo, I... am... STUFFED!\" ",
"It doesn't really. It's purely for dietary adherence. Check something like /r/leangains for a protocol where people don't follow the 'small portions often' mantra. ",
"It doesn't. What makes you lose weight is a caloric deficit between what you consume and what you burn off daily. You can eat all your calories at night or break it down into smaller meals to feel full, but neither way matters to weight loss. "
]
} | []
| []
| [
[],
[],
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[]
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|
||
25nfeg | what's so special about russian engines and why we can't build our own? | I mean we have a wide experience in missiles, jet engine and even ICBM technology. Why is that we can't build an engine to go space? | explainlikeimfive | http://www.reddit.com/r/explainlikeimfive/comments/25nfeg/eli5_whats_so_special_about_russian_engines_and/ | {
"a_id": [
"chivgkr",
"chivl90",
"chiwnbt"
],
"score": [
2,
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],
"text": [
"Unless OP is not American...",
" > I mean we have a wide experience in missiles, jet engine and even ICBM technology. \n\nThe US does have this experience, the best of any place in the world, but building rocket motors is still one of the most difficult engineering, designing, manufacturing, and testing tasks the human race has ever had to solve. It is really really hard to build them, it takes immense amount of time and money to even have a chance to build them, let alone actually getting them to *reliably* work.",
"We'd also be fucked if the Chinese stopped making our electronics.\n\nIt's not because we don't know how, we've just given up on doing it for ourselves because it was cheaper to let somebody else do it. If they stop unexpectedly, we'd have to do a lot work to get factories & trained workers lined up to do it for ourselves."
]
} | []
| []
| [
[],
[],
[]
]
|
|
26sd3r | copyright laws with holy books | How are the Bible, Quran, and Torah published? Are there any copyright laws? Can any publishing company decide to print them? Are they technically "open source?" | explainlikeimfive | http://www.reddit.com/r/explainlikeimfive/comments/26sd3r/eli5_copyright_laws_with_holy_books/ | {
"a_id": [
"chtzmxl",
"chu24rq"
],
"score": [
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],
"text": [
"The books are in the public domain, but the translations of them can be covered by copyright. So, if you want to publish the Bible, you have four choices:\n\n- Print it in the original text (Hebrew, Greek, Aramaic)\n- Print a translation in the public domain (such as KJV)\n- License a copyrighted translation (such as NIV)\n- Perform your own translation.",
"The Bible itself and some older translations was written long enough ago to be in the public domain, as any copyright has by now expired, although recent translations may be copyrighted. The same is true for many major religious texts, meaning that if the right translation is chosen you or a publishing company could print them at will.\n\nHowever, Scientology still holds copyright over most of its bibliography and has sued several organisations for reproducing it, so be sure to check before you choose to print anything!"
]
} | []
| []
| [
[],
[]
]
|
|
251ql3 | where do rich people whose assets are mostly tied to company stock get their spending money? | For example, Mark Zuckerberg or the guy who owns SnapChat, where do they get their disposable income? Do they sell share of their stocks? For private companies, how does this work? | explainlikeimfive | http://www.reddit.com/r/explainlikeimfive/comments/251ql3/eli5_where_do_rich_people_whose_assets_are_mostly/ | {
"a_id": [
"chcs7pj",
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"score": [
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"text": [
"For guys that made their money by being owners of companies that eventually go public, they sell their stock. The major insiders of a company have to disclose all stock transactions, so you can actually see who at Facebook is [selling shares](_URL_0_). In December Zuckerberg sold 41 million shares of Facebook stock for over $2 Billion. That's not bad for walking around money.\n\nFor smaller non-public companies the owners aren't going to get their money from selling shares of the stock. Instead most of their income (if they business is doing quite well) comes from the profits of the company in the form of bonuses and dividend payments. If the company is quite small, then the owner likely is simply taking a salary (which is true of all the other examples as well, it's just a small part of the payment for the super rich CEO types).",
"ELI5: Sometimes when a company makes a lot of money, it gives a tiny bit of that money to everybody who owns part of the company (each little piece being called a \"stock\"). Because these people own a lot of little pieces of the company, they get a lot of little bits of the money, which adds up to lots of money. When a company shares money like this, the little bit they give to each person is a \"dividend\".\n\nSome companies make so much money that they can do this every few months, and this can be like a paycheck for the people who own lots of the stocks.\n\n\n > [A dividend is a payment made by a corporation to its shareholders, usually as a distribution of profits.\\[1\\] When a corporation earns a profit or surplus, it can either re-invest it in the business \\(called retained earnings\\), or it can distribute it to shareholders. A corporation may retain a portion of its earnings and pay the remainder as a dividend.](_URL_0_) \n\n^^^EDIT: ^^^I ^^^got ^^^a ^^^Reddit-Dividend! ^^^Thanks ^^^for ^^^the ^^^smile, ^^^whoever ^^^you ^^^are!",
"If they do not have dividends, then they sell shares of stock. But think about the millions and millions of shares they own, they do not have to sell a significant stake in order to have spending money. ",
"I've read that many of them get their spending money from credit and short term loans, which they later pay back when investments have paid off. They easily qualify for the loan due to the high amount of collateral they can provide. They can do this and have it be worthwhile because the return on investment is substantially higher than interest rate on the borrowed money.",
"Dividends. If the stock does not pay dividends, they might have to sell. They might get a job, like CEO or someting. ",
"The rich people can get a loan which they promise to pay back using the money they make by selling the shares when they are allowed to sell them. \n\nBecause the loan is _collateralized_ it will have a very low interest rate and good terms.",
"Of course, one can sell some or all of their stock, if the company is public. When a person sells their stock, they sell for cash. So maybe Mark Zuckerburg will sell *some* of hist stock for $50 million, which is tiny bit of stock for him. [This past December 2013, Zuckerberg sold 41.4 million of his own shares for $2.3 billion.](_URL_0_)\n\nThe reason a lot of people do this is that companies that are high-growth do not pay dividends. Instead of paying $70 million to all the stockholders, they pay zero. This is generally well known to investors, so they ar not surprised.\n\nThis, in fact, is why the original investors want the company to go public as fast as they can. So that they can cash out pronto and put their money into another start-up.",
"-they still have pretty high salaries\n\n-dividends\n\n-they sell some stock "
]
} | []
| []
| [
[
"http://finance.yahoo.com/q/it?s=FB+Insider+Transactions"
],
[
"http://en.wikipedia.org/wiki/Dividend"
],
[],
[],
[],
[],
[
"http://www.ft.com/cms/s/0/f16b06a4-68a5-11e3-996a-00144feabdc0.html"
],
[]
]
|
|
axlh17 | why doesn’t food get into our lungs? | If we breathe and eat simultaneously, what separates food from oxygen? | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/axlh17/eli5_why_doesnt_food_get_into_our_lungs/ | {
"a_id": [
"ehu8yo3",
"ehu8z7s",
"ehu92ir"
],
"score": [
3,
40,
3
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"text": [
"Food goes down the esophagus, air goes down the trachea. The trachea closes when we swallow so that no food gets into our lungs.",
"Basically you have two pipes, breathy pipe and eaty pipe. They are the same at the mouth and throat but diverge into two. Where they diverge is a flap of tissue called the epiglottis. It closes off the breathy pipe when swallowing food and drink. When breathing it closes off the eaty pipe. Sometimes the flappy flap messes up when eating and breathing making it not close off the breathy pipe, causing choking ",
"There is a flap in the back of your mouth that covers the hole that air goes down when not breathing."
]
} | []
| []
| [
[],
[],
[]
]
|
|
51s7zo | what happens when you misspell a url but it takes you to the correct website anyway? | Did the owner purchase all domain names that are common typos and redirect them to the proper website? | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/51s7zo/eli5_what_happens_when_you_misspell_a_url_but_it/ | {
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"score": [
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"text": [
"Yup, pretty much exactly your assumption. Either they own the alternate URL or they pay the owner to redirect (_URL_0_ takes you to google, for example). ",
"This is often the case, yes. Ever been to _URL_0_ ? It will automatically redirect you with a ~~cute~~ snarky little message about the plural of Lego being Lego.",
"Companies will often buy misspellings, plurals, variations, etc. of their domain name and re-direct them to their actual site... better than some scammer registering it and setting up some site to get ad clicks or affiliate revenue, or competitors grabbing it to redirect to their site. And considering that domains cost less than $10/yr, it's a nominal expense for a business to protect its brand.",
"Usually, yes.\n\nHowever, you still need to be careful: sometimes a scammer will get there first, or will register a domain the real site didn't think of. You might get directed to a site that *looks* like the one you're trying to get to, but actually isn't.\n\nA couple of years ago, as a YouTube Help Forum Top Contributor, I had to give the bad news to several people who demanded to know where their iPhones were. Apparently, they'd been \"randomly selected\" to participate in a survey, for which they were promised an iPhone or an iPad or something similar. They hadn't, or course -- a Google company was hardly going to give away a competitor's products. Rather, they'd mis-typed the address and had just given some personal information to a fake site."
]
} | []
| []
| [
[
"gogle.com"
],
[
"www.legos.com"
],
[],
[]
]
|
|
49vd48 | why do young mammals, humans included, always act so playfully? | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/49vd48/eli5_why_do_young_mammals_humans_included_always/ | {
"a_id": [
"d0v5pam",
"d0v5qqa"
],
"score": [
2,
2
],
"text": [
"For most animals, play is a way to learn and grow. They learn social skills, hunting skills, and others while encouraging muscle growth and motor skill control.",
" > [Play is not just a pastime activity; it has the potential to serve as an important tool in numerous aspects of daily life for adolescents, adults, and cognitively advanced non-human species (such as primates). Not only does play promote and aid in physical development (such as hand–eye coordination), but it also aids in cognitive development and social skills, and can even act as a stepping stone into the world of integration, which can be a very stressful process.](_URL_0_)"
]
} | []
| []
| [
[],
[
"https://en.wikipedia.org/wiki/Play_(activity\\)"
]
]
|
||
3ksb5c | why do some laptop screens are dark when looked from below but bright from above? | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/3ksb5c/eli5_why_do_some_laptop_screens_are_dark_when/ | {
"a_id": [
"cv03pj7"
],
"score": [
2
],
"text": [
"Because it's backlit from the bottom. The screen can be viewed without a backlight, but it's so dark and faint that it's almost impossible to use. "
]
} | []
| []
| [
[]
]
|
||
7vwn9s | does atmosphere influence the way music sounds? | Was just thinking about this since Elon Musk sent this car to Mars whilst playing David Bowie. I wonder if changes in atmosphere have an effect on sound waves by making them sound higher or lower, or slower or faster? | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/7vwn9s/eli5does_atmosphere_influence_the_way_music_sounds/ | {
"a_id": [
"dtvnhco",
"dtvsa8t"
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"score": [
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3
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"text": [
"The car is in vacuum and there is no sound in vacuum.\n\nYou need a medium for sound so if the speaker are playing the song there will be some vibration in the rest of the car as sound can travel in it. But if you where in a space suite beside the car you would not hear anything. If you pressed the helmet to the car you might hear the some sound.\n",
"To answer your question, kind of. But let's clarify your question a bit. The speed of sound is affected by such things as density (altitude and humidity) and temperature. Our brave Roadster, now in the depths of the Black, is no longer producing any sound waves due to the lack of air density (it's in a vacuum). \n\n\n\nHowever, while it's still in the atmosphere, do these changes in density and temperature affect the pitch of sound? No. The audio won't pitch up or down due to changes in density. The only thing that will happen is the speed of sound will get slower and slower, which effectively means it is getting softer, until it reaches the vacuum of space where sounds will not transmit. This is not the same as the song getting slower like putting a finger on your record player; this simply means instead of reaching your ears in...say 5 seconds... it now reaches your ears in 10 seconds.\n\n\nAny changes in the pitch can be attributed to our perception of the sound as it passes by (doppler effect). As it gets closer to us the sound waves \"bunch up\" and it sounds pitched higher. When it passes and moves away, the sound waves \"spread out\" which gives it a lower pitch. Note that this is not directly related to air density (or vacuum) at all.\n\n\nTLDR: the changes in atmosphere will not change the pitch of David Bowie. It will simply get softer and softer as it fades into The Black."
]
} | []
| []
| [
[],
[]
]
|
|
6iljye | why does womens' fashion offer so many more options in terms of clothing types than mens' fashion does? was it always like this? | As the title states, my question is as to why there are so many different types of clothing available for women's fashion compared to men's fashion. Specifically I'm wondering about clothing types that are considered appropriate for professional wear. It seems odd that this division would have developed. | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/6iljye/eli5_why_does_womens_fashion_offer_so_many_more/ | {
"a_id": [
"dj74sqy",
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"score": [
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"text": [
"Business attire is conservative. In the past women had much fewer choices and were required to wear dresses of a certain length and often of muted color(depending on position of course). As sexism started to get called out women began wearing pantsuits and other fashions to work. \n\nThere's a lot of options for men but since the goal is to stand out only very slightly in order to appear professional we really only get to express it in tie form. Unless you are in a \"creative\" type position people aren't looking for how you want to express yourself. Artistic flare is seen as detracting from your ability to get the job done efficiently and professionally.",
"Men's clothing has traditionally followed **military dress**. Since military dress is generally restricted to only three or four uniforms, men generally only get a few different kinds of styles to choose from. Fashion designers have always tried to make men look **manly**, which stems directly from the military background because men in the military are considered very manly.\n\nWomen's dress was seen as a way to attract husbands, and so they're often garish and exciting, which lead fashion designers to try to outdo each other in garishness and excitement. ",
"You have to look at this on a case by case basis, some of these extra types of clothing have a knock-on effect. For example, pockets have never been popular in dresses and this has created a demand for handbags or clutches.\n\nHeels and skirts emphasise legs while serving no practical purpose for walking or protecting your legs from thorns or knees while kneeling. Women have traditionally been objectified as objects of visual attraction while men have traditionally been objectified as performers of manual labour. These clothing types conform to that and so much so that womens trousers still don't have pockets (which is itself a knock-on effect of women carrying bags).\n\nBreasts are the central reason for the different types of tops for women. Tops are either opened at the chest in some way or hanging from the front or back to show/emphasise something, again for beauty. For men most tops are functional, vests do emphasise muscle but it's less common.\n\nFinally, since we are only just approaching real equality in the work place the business suit has driven mens fashion for decades or centuries. ",
"The minimal business suit was a fashion trend that started with capitalism. The idea of capitalism was to let your money do the work for you. And buying expensive clothes for yourself is not making the money work for you. So non-capitalists you would wear fancy clothes to show how rich you were but capitalists would wear simpler clothes to show how well they were at handling money. And this is a trend that have only grown more and more. It was not long ago that the proper business attire included a hat and vest. And even now the tie is becoming optional. That is unless you drop the shirt and jacket all together and go for a nice sweater.\n\nThe woman's fashion options have remained more diverse. This was because women generally were not capitalists. So they were given more freedom in showing off how wealthy their husbands were. However there have been a lot of changes here as well and it is not that acceptable to wear big fancy dresses on a daily basis as it was back in the day. But if you go back 300 years both men and women would have similar width of options to chose from. Crazy suits with lots of intricate details similar to how ballroom dresses looks like were not uncommon among the rich men. And just as women have lots of different options for accenting their curves in the upper torso men had similar options for accenting their curves in the lower torso. High heals were first invented to be used by men."
]
} | []
| []
| [
[],
[],
[],
[]
]
|
|
2uaa61 | how can somebody be charged with attempt to commit a crime and the act of committing the crime? | For example, somebody is charged with attempted murder and murder in the same case. | explainlikeimfive | http://www.reddit.com/r/explainlikeimfive/comments/2uaa61/eli5_how_can_somebody_be_charged_with_attempt_to/ | {
"a_id": [
"co6ngm3"
],
"score": [
2
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"text": [
"They can be charged with both, but they can**not** be *convicted* of both. Not for the same incident, at least.\n\nUsing your example of the person charged with both rape and attempted rape, this could be two separate instances. So if the person attempted rape, but didn't complete the act, then came back the next day and completed a rape act, that's two instances. One attempted rape and one rape. Thus the defendant could be convicted of both the attempted rape and the later actual rape because each represents a separate incident.\n\nWhat cannot happen is one single instance being used to support a conviction for both crimes. The Merger Doctrine prohibits this. The attempted rape charge is what is known as a \"lesser included offense.\" If the jury finds that the defendant is not guilty of rape, the jury may still find that the defendant is guilty of attempted rape. But if the jury finds the defendant guilty of the rape itself, the attempt charge \"merges\" with the rape charge and there is only the single conviction for the rape, with no possible conviction for the attempt charge."
]
} | []
| []
| [
[]
]
|
|
601bt1 | how do digital cameras turn the image into a digital file? | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/601bt1/eli5_how_do_digital_cameras_turn_the_image_into_a/ | {
"a_id": [
"df2phpd"
],
"score": [
2
],
"text": [
"A focused image is put on the sensor by the lens(es). The sensor is essentially a big old array of photosensors, devices which measure the intensity of light and convert it to a voltage. The camera's electronics read the value of each element of the sensor array, which forms either a single pixel (in the case of a black-and-white sensor) or one of the subpixels in a pixel (in the case of a colour sensor). Take those values and arrange them in a file, and you have a RAW image, which can be converted into JPEG or whatever else you like, either by the camera itself or your own computer."
]
} | []
| []
| [
[]
]
|
||
35kgrj | why am i able to pick up a 50kg dumbbell with one hand and carry it with relative ease but picking up an entire desk that's 30kg is a ball ache? | Title.
Sorry if it's a repeat question. | explainlikeimfive | http://www.reddit.com/r/explainlikeimfive/comments/35kgrj/eli5_why_am_i_able_to_pick_up_a_50kg_dumbbell/ | {
"a_id": [
"cr594od",
"cr594wj"
],
"score": [
2,
15
],
"text": [
"It's the awkwardness and leverage. You're holding the dumbell right under its center of gravity. But the desk uses your arm like a lever so it weighs more. Desks are dicks. ",
"They have the same weight (downward force), but the desk has more torque (rotating force). \r\r\rThe dumbbell is very compact, all the weight is right in your hand. The torque produced on your hand is zero, it's only trying to push your hand down. That's said, as you probably know, holding a dumbbell close to your chest is easier than arms extended. Why? The longer you stick out your arm, the more it acts like a lever. When you are is fully extended, not only do you have to support the weight, but you also have to keep your arms from rotating about your shoulder. \r\r\rThe desk is much the same, like arms extended with a dumbbell you have a lever. Basically the desk not only applies a downward force, but since it's centre of mass (centre of the desk if symmetrical) is out past your hands, it's trying to twist around you hands. Also, like the dumbbell your hands are also trying to rotate around your shoulder. Now you have to apply enough force to keep the desk up, enough torque to keep the desk from just rotating about where you are gripping it, and enough torque to keep your arms from just rotating around your shoulders. "
]
} | []
| []
| [
[],
[]
]
|
|
4zz0iz | why does it seem easier to perform a pull up if you simultaneously lift your knees upward? | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/4zz0iz/eli5_why_does_it_seem_easier_to_perform_a_pull_up/ | {
"a_id": [
"d6zwdsz"
],
"score": [
3
],
"text": [
"Depends how you lift your legs. If you swing them then you are creating momentum from your leg/lower body muscles thus your back/arms do not have to work so hard.\n\n\nIf you lift your legs 1st then your weight distribution is different (you are no longer hanging straight down). Apparently this slightly off vertical position changes muscle use a small amount which makes it feel easier. This one is kind of an illusion since you will be expending the same amount of energy to move your body just you will be using muscles that are stronger or a few more muscles. Apparently this is still bad to do and you should just hang but I am no fitness guru as my belly would prove."
]
} | []
| []
| [
[]
]
|
||
5jp9s7 | why paper is generally white? | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/5jp9s7/eli5_why_paper_is_generally_white/ | {
"a_id": [
"dbhx1w0",
"dbhxaq5",
"dbi0z5e"
],
"score": [
15,
2,
3
],
"text": [
"Paper is bleached during the manufacturing process because colors stand out better against a white background. ",
"That very much depends on *what* kind of paper you're talking about. \n\nPaper used for reading or writing is generally white because that' the most neutral colour for other colours to show up on. But papers made for other uses are *not* necessarily white! ",
"One of the reasons we stain wood is to make its color consistent. So bleaching of wood pulp makes the ground up wood consistent in color.\n\nAccording to the _URL_1_ article [*How is paper colored*](_URL_0_)\n\n > Ans. Unbleached fibers are brown in color. If paper is to be colored dark, unbleached paper can be directly colored, otherwise fibers are bleached before coloring. \n\nSo logically bleaching to get a standard white pulp that would be modified at various points in production (either adding dye to the bleached pulp, spraying or coating it wet or dry prior to cutting) would maximize production of a lot of colors including various degrees of white."
]
} | []
| []
| [
[],
[],
[
"http://www.paperonweb.com/A1024.htm",
"paperonweb.com"
]
]
|
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