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fikfs
|
Since humans can change time-zones, can we adapt to longer days/nights?
|
We know that if we were to move to Japan, it takes a couple of weeks to adjust to the different time zone hours.
If we were to move to a planet that, e.g. takes 32 hours to complete one rotation on it's axis, would a human ever be able to adapt to sleep longer hours & comfortably stay awake for the duration of daylight?
If so, what is an estimate to how long it would take to adapt?
Will it affect our mental health?
|
askscience
|
http://www.reddit.com/r/askscience/comments/fikfs/since_humans_can_change_timezones_can_we_adapt_to/
|
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"Perhaps. The body's native circadian rhythms have a natural period (that is, what the circadian cycle would be like if you had constant darkness or light) that is very close to 24 hours, but is not exactly. This rhythm is modulated by light- which is how rhythms can adapt to a 24 hour rhythm and change in response to natural light patterns. \n\nIn order to adapt to a 32 hour day, it would be pretty severely desynchronized from the biological 24 hour pacemaker rhythm. You should actually have to do experiments, and this would be hard to determine. I think I heard that with people trying like the 28-hour days, people have difficulty entraining to a 28-hour clock, but don't trust this at all because I don't have a reference and don't even remember where I heard it from."
]
}
|
[] |
[] |
[
[]
] |
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1kpsnr
|
how we use hubble's law to measure distances.
|
having issues getting my head around this.
|
explainlikeimfive
|
http://www.reddit.com/r/explainlikeimfive/comments/1kpsnr/eli5how_we_use_hubbles_law_to_measure_distances/
|
{
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"text": [
"You see, the Universe is expanding. Not just at the edges, but everywhere. The space between any two points is expanding whether it is the space between galaxies or the space between your hands.\n\nWe know how fast space is expanding and we know how fast far away objects like galaxies SHOULD be moving. By comparing how fast we SEE them moving with how fast they SHOULD be moving, we can know how fast space is expanding between here and there. Since we know how fast space grows, we know how much space there must be between here and there to grow that fast.\n\nExample: Making up numbers, let the speed space expands be 1 speed unit for every 10 distance units. We see a galaxy moving at 50 speed units. We know from various sciencing that it should be moving at 40 speed units. We conclude that 10 speed units must be from space expanding. From that we calculate that the distance to that galaxy must be (10 distance per 1 speed) 100 distance units."
]
}
|
[] |
[] |
[
[]
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|
ami5q7
|
Does alcohol settle out of solution over time?
|
askscience
|
https://www.reddit.com/r/askscience/comments/ami5q7/does_alcohol_settle_out_of_solution_over_time/
|
{
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"text": [
"No. Alcohol and water are 100% miscible, meaning they blend together perfectly. For something to settle out of solution, you would need it to precipitate. "
]
}
|
[] |
[] |
[
[]
] |
||
9qpvck
|
how an empty pan left on a turned on stove burns?
|
explainlikeimfive
|
https://www.reddit.com/r/explainlikeimfive/comments/9qpvck/eli5_how_an_empty_pan_left_on_a_turned_on_stove/
|
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"Dont know about gas stoves but i do know that most pans/pots will melt before they catch fire (had a herion user as a roommate when we lived with my uncle as a kid) ",
"A stainless steel or cast iron pan will have a layer of oil coating the metal. Metal won't burn at such a low temperature, but most oil will. Non-stick pans on the other hand are coated with Teflon, which starts breaking down around 500 degrees in freedom units. Not sure when it'll outright burn though."
]
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|
[] |
[] |
[
[],
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6jujjl
|
What makes something an acid and what makes something a base?
|
I've heard somewhere that acids have a sour taste and a bases have bitter tastes. But I've heard that water is a base and acid? This confuses me a lot.
|
askscience
|
https://www.reddit.com/r/askscience/comments/6jujjl/what_makes_something_an_acid_and_what_makes/
|
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"text": [
"The concentration of H+ ions in an acqueous solution is what defines acids and bases. A strong acid such as HCl will dissociate and you'll have tons of H+ ions (and tons of Cl- ions) in the solution. A strong base will dissociate too and the calculation is the pH is slightly more complicated. For now it suffices to say that at room temperature you have pH = 14 - pOH, so you can derive the pH from your concentration of OH-. \n\n If the concentration of H+ is very high, pH it's low and it's an acid, if the concentration is low, pH is high, it's a base. pH usually ranges 0 to 14 and it's a logarithmic scale. 7 is neutral. \n\nFoods: bitter or sour they are almost all acids, only a selected few are slightly alkaline (bases). NaHCO3 (baking soda) is mildly alkaline dissolved in water. Tastes salty because it has sodium in it. pH of a lemon is 2 (citric acid), pH of vinegar (acetic acid) is similar (but they don't taste the same), not does honey with a typical acid pH of 4, if I remember well. The are *no* foods that are as strong base as lemon is on the strong acid front.\n\nDistilled water has a pH of 7 (it can't have another one), however you *always* drink water with some salts and minerals dissolved in it, this means you can have water with pH ranging from 6.5 to 8. Yes, it can be acid or alkaline.",
"It depends. Definitions can differ.\n\n1. simple pH. If it's below 7, it's acidic, if it's exactly 7, neutral and above it's a base.\n2. Proton donator and acceptor. Acids have protons (H+) and give them up so they are the donators and the base has a free electron pair (or more) takes them in with a covalent bond. (Brønsted)\n3. Donator or acceptor of electron pairs. Here it's reversed, the one that accepts the covalent bond and the base is the one donating it. (Lewis)\n\nps. please excuse issues with terminology i'm neither a native english speaker nor a chemist.\n",
"I got this,\n\nSo [assuming you're familiar with the gist of the periodic table, that elements are defined as the number of protons they're made up of, hydrogen is 1 because it only has one proton, helium is 2 because it has two, ect., and that elements are neutrally charged, so long as they have exactly one electron for every proton (and that electrons will favor the elements on right side of the table).] I'll explain how i understand the Bronsted-Lowry theory, which is basically all you really need to know to understand the difference between an acid (something acidic) and a base (something alkaline). \n\nThe difference between an acid and a base ultimately what it does with protons in a solution (a liquid it dissolves in). If it adds protons, it's an acid, if it takes protons away it's a base.\n\nI'm going to use the example of water as a solution because it's pH is neutral. [The pH is a scale from 0-14, 0 is really acidic, 14 really alkaline, and pure water is a 7]. \n\nPure water, [H2O but I prefer to write it HOH, is as I'm sure you know, just a compound made of two hydrogen atoms and one oxygen]. Frozen it's a crystal of HOH, but as a liquid it's actually a balanced mixture of H+ and -OH ions (ions are just charged molecules). H+ is free in solution because hydrogen atoms only have one proton, so they suck at keeping their electrons if it's warm (also why they're on the left side of the periodic table), so oxygen, being needy takes it and slightly repels the H+ ion. Really what H+ is, is a single bare proton. [You might be like, \"hey what about the neutron\", as it turns out hydrogen doesn't have one]. My point is that water is a solution made up of a balance of free protons and -OH. When something is added to this solution it either contributes to the number of free protons (an acid), takes up the protons (a base) or nothing (neutral or insoluble).\n\n When a solution becomes acidic it has an excess of protons. [For example, HCl is an acid because Cl- (chlorine) REALLY likes electrons, so it basically repels its hydrogen atom when it's added to water, leading to an excess of protons.]\n\nWhen a solution becomes basic it has a deficit of protons. [For example, NaOH is a base because when it is added to water it dissolves into Na+ and -OH, resulting in an excess of -OH.]\n\nSo that's all. Neutral liquid water is a ratio of H+ to -OH and the difference between an acid and a base is how it effects the ratio.\n\nFor reference, the human body is slightly acidic, but an extreme excess of protons (as in acids) or extreme lack of them (in bases) can deconstruct proteins causing cells to die. This is why strong acids and bases are dangerous and can cause burns. As such, the body requires a certain pH to function properly, so evolution granted us a detection system for acidic or basic foods. Thus why acids are sour and bases bitter. Granted, bases are primarily repulsive because many natural toxins are fairly alkaline.",
"Those are observational characterizations. But for an actual _definition_ or _model_ on a molecular level, there are 3 in use, each one progressively more general than the other:\n\nThe first is the _Arrhenius definition_, which says that an acid is a compound which breaks down to release H+ ions when it hits water, and a base is a compound which breaks down to release OH- ions when it hits water. Hydrochloric acid (HCl) and sodium hydroxide (NaOH) are classic examples respectively of an Arrhenius acid and Arrhenius base.\n\nThe second definition is the _Bronsted-Lowry_ definition. The definition of acid is not really different -- it is that it is a proton (H+ again) donor, so it releases H+. But a _base_ is a proton (H+) _acceptor_ . In this case, NaOH is not _directly_ a base, but the OH- it releases accepts an H+ to form H2O. So we also consider NaOH a base. This allows for an extension to other substances that do not contain OH directly. An example is ammonia, NH3. This is a weak base. When it hits water, it accepts a proton from H2O directly, becoming NH4+ . This also, though, forms an OH- ion.\n\nThe third and final definition is the _Lewis_ definition. In this case it is extremely general: an acid is an _electron pair_ _acceptor_, while a base is an electron pair _donor_ -- note that compared to before the \"donor\" and \"acceptor\" roles are reversed. HCl, then, breaks apart and the H+ can accept an electron pair. When neutralized with NaOH, the OH- donates the electron pair (note that OH*, with no charge, has an unpaired electron i.e. is a free radical, so OH- has one extra electron thus a full pair). While Bronsted-Lowry extended the range of bases, Lewis extends the range of acids. In particular, BF3 (boron trifluoride) is an acid by this definition but not by any of the others (it lacks a proton). The first two definitions pretty much cover (in particular, the second) acid-base behavior in water – this next definition allows us to go beyond water to other types of solvent (e.g. BF3 can be dissolved in hexane.).\n\nWhat it means to say water is both an acid and base, the simplest way to see this is by the Arrhenius definition: it can ionize to make either H+, or OH-, given H2O = HOH. A compound that can serve as both an acid and a base is called “amphoteric”.\n\nFWIW, if you dump BF3 in water it forms an acid solution alright, but it no longer exists as BF3, rather it reconfigures itself into “conventional” (Bronsted-Lowry, Arrhenius) acids. According to one source though this reaction is described as rather \"violent\". Ouch. Don't try that at home kids. (And given your own body is mostly water you can probably guess it would not be a good idea to be exposed to this stuff. :) )"
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14zmj1
|
What made the Normandy invasion so significant compared to the other battles in WWII? Why is this the one most often talked about?
|
AskHistorians
|
http://www.reddit.com/r/AskHistorians/comments/14zmj1/what_made_the_normandy_invasion_so_significant/
|
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"I assume you mean what is the significance from an american/western perspective yes? In the larger ww2 scheme the invasion is certainly siginificant although probably not as significant as it's often regarded in the west.\n\nBut onward with the significance.\n\nNormandy is important because it finally opened the much wanted **Western Front** in the war. The main demand that Stalin pressed on GB and the USA, at the summit meetings before 1944, was a western front to relieve some of the German pressure on the USSR. Until the invasion the US and GB contributions had been limited to sideshows in the Mediterranean and strategic bombing + of course the supplies sent to the Soviets through Iran and Murmansk. Normandy finally opened a land front close to the German heartland that the Germans had to defend (thus weakening the eastern front). \n\nThat is not to say that Normandy won the war or anything, mid 1944 the Russians were already beating back the Germans rather well through operation Bagration.\n\n**Sheer size** might be a factor, it was indeed the largest amphibious attack ever performed, and it involved a large amount of troops from the western powers. Even more were involved if you count the breakout battles coming after the invasion. The french campaign was the main event for GB and USA in Europe, it was just a lot bigger than what took place in Italy and North Africa. \n\n**Hollywood** can't be discounted in creating popular memory of events. In the years following you get movies like *The longest day* starring John Wayne depicting the invasion. Later on you get many more movies showing the invasion (Private Ryan & Band of Brothers come to mind).\nThe eastern front had no such coverage and besides by the time Hollywood was shooting movies of D-Day the Russians were the Red Enemy so their contribution to the victory was not something that got much attention. "
]
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[]
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vundk
|
how did the us go from a budget surplus under clinton to a massive deficit now?
|
I understand that the tech-bubble burst, but what were the other factors/when did they occur?
|
explainlikeimfive
|
http://www.reddit.com/r/explainlikeimfive/comments/vundk/eli5_how_did_the_us_go_from_a_budget_surplus/
|
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"THE most expensive thing (by far) in the world is war. ",
"Mostly war but also tax cuts for the wealthy. ",
"When GWB was president:\n\nWe had 2 Wars **NOT PAID FOR**\n\nLarge Tax Cuts **NOT PAID FOR**\n\nPrescription Drug Plan **NOT PAID FOR**\n\nHome Land Security Bill **NOT PAID FOR**\n\nThe economy tanked and a lot of companies went under and unemployment went up and these people and companies are now not paying taxes. When you combine spending like crazy without paying for it either by cutting something else or raising taxes and the economy tanking this is why you have a large deficit now. \n",
"IIRC, the Clinton era numbers depended on a booming economy. Turns out that economies don't always boom. The aging population and increasing health care costs are increasing Medicare, Medicaid, and Social Security. Interest on the national debt is starting to be a significant chunk of the pie. War and unrealistically low taxes don't help, but they are only a slice of the problem.",
"The Bush Tax Cuts, and two wars.\n\n- in June 2001 (5 months after being elected) President issued a retro-active tax cut; that was paid for using Social Security\n- in September 2001 a war in Afghanistan started\n- in March 2003 a war in Iraq started\n- in May 2003 there was a *second* round of tax cuts\n- in January 2006 Medicare Part D (prescription drug benefit) was enacted\n\nELur5: President Bush spent more more, and took in less money, than Clinton",
"Keep in mind that the clinton era was during a massive technological leap (the internet / computers) which were the main contributing factor in the surplus. Along with lesser war spending and less tax cuts.",
"I'll do my best to explain this. But if you get confused by any numbers, go straight to the bold conclusions.\n\nLooking at budget numbers:\nIn 2000, we spent $1.79 trillion we got $2.03 trillion in taxes. \nIn 2012, we are projected to spend $3.80 trillion and get $2.47 in taxes. ([source](_URL_0_))\n\nSaid another way, **over 13 years, we're spending 112% more than we used to. We're also only bringing in 22% more money now than we did in 2000.**\n\nAs a percentage of the economy: \nIn 2000, our spending was 18.2% of the economy, and we taxed 20.6% of the economy.\nIn 2012, our spending is planned to be 24.4% of the economy, and taxes 15.8% of the economy.\n\nSaid another way, **over 13 years, spending has grown by 6.2% of the economy. Taxes have shrunk by 4.8% of the economy.** \n\nAs for what things were spent on, as a percentage of spending:\n\n 2000 2012\n Defense 16% 18.8%\n Medicare 12% 14.8% \n Medicaid 6.6% 6.9%\n Social Security 22.9% 20.2%\n\nNow remember, spending has shot up 112%. Those four programs took up roughly three-fifths of our spending in 2000, and they take up roughly three-fifths of our spending in 2012. Said another way, **these 4 programs have grown consistently as spending has grown. All are at fault to blame for the rise in spending, some only slightly more than others.**\n\nAs for tax changes,\n\nIn 2001 and 2003, there were two rounds of Bush tax cuts. In 2009, Obama pushed the stimulus, which cut taxes further, and those temporary tax cuts have still been continued until today. Those are the major changes in the tax code. \n\nTo see these changes, look at taxes as a percentage of the economy:\n\n 2000 2002 2004 2006 2008 2010 2012\n % of economy 20.6% 17.6% 16.1% 18.2% 17.6% 15.1% 15.8%\n\nYou can see these numbers dip in response to new tax cuts. You can also see them dip and rise according to the economy. For example. In 2000, taxes were high, and the economy was in a bubble state. In 2004 they dropped after two Bush tax cuts. In 2006 the economy was good, and tax money was back to historical averages. By 2010, Obama's tax cut hit, plus the economy was bad. \n\n**Overall conclusion: There is no single, easy thing to blame. Spending has shot way up, taxes have gone way down (though not by as much as spending has shot up). Major budget programs are all growing as spending is growing. Also, it's also harder to compare a bubble year of 2000 to a recovery year like 2012. (Incidentally, wars are blamed in the comments. War spending as a percentage of the budget is surprisingly small. During the worst years of Afghanistan and Iraq war spending, it contributed to roughly 5% of federal spending. Today, it's much lower as Afghanistan is winding down and we aren't militarily in Iraq.)**",
"Keep in mind that there was still a massive national debt in the Clinton years. It's as if you owed $50k in credit card bills and only planned to pay off $100 that year. Then your budget winds up with $25 extra because it was an unusually good year, and even though your debt is still skyrocketing because of interest, you pat yourself on the back for having a \"budget surplus.\""
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|
rx90i
|
Does a phone get lighter as the battery drains?
|
As I use my phone, photons are being released from the screen, heat is being dissipated, and the energy in the phone is being used. Does any of this affect the weight of the phone? Is my phone lighter and if so by how much? Does charging it add weight back?
|
askscience
|
http://www.reddit.com/r/askscience/comments/rx90i/does_a_phone_get_lighter_as_the_battery_drains/
|
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"Yes - charging the phone adds weight (all other things being equal). A really, really small amount. Your fingerprint on the phone makes significantly more difference. You probably scrape off more metal/plastic plugging in the charger than the mass equivalent in charging the battery.\n\n[See...](_URL_0_)",
"the top rated comment is wrong. \n\nwhen recharging a battery you do *not* add or subtract any mass **from the system**(system being the battery). batteries produce electricity with a chemical reaction that involves free electrons going from one pole to the other, creating a current (ampere is a measurement of electrons passing through a conductor per second). these electrons are still within the battery when it is flat. when recharging a battery, you reverse the chemical process by inducing a voltage drop greater than the output voltage of the battery, forcing the electrons to go back to their original position. \n\n\nedit for clarification"
]
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|
[] |
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[
[
"http://www.reddit.com/r/askscience/comments/qxdai/does_a_battery_weigh_more_when_charged_as_opposed/"
],
[]
] |
|
a81e0l
|
When did it become a common thing for employers to drug test their applicants? What events could be linked to the reason employers began doing it?
|
AskHistorians
|
https://www.reddit.com/r/AskHistorians/comments/a81e0l/when_did_it_become_a_common_thing_for_employers/
|
{
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"ec87icm"
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"text": [
"This is an interesting question without much historical background. This sub requires historical evidence prior to 1998 in its answers. There is not a lot from before 1998 on this topic. You may want to post somewhere else. \n\nWith that being said, the answer is three fold.\n1) The drug war.\n2) Drug testing in the workplace greatly reduces the cost of health care.\n3) Drug testing is an excellent way to get rid of a bad employee immediately. In part it has become policy because in order to test 1 person, you have to test everyone to avoid legal troubles.\n\nDrug testing in the workplace really began with the onset of the drug war. President Reagan began requiring drug testing for federal employees in 1986. Large companies immediately followed suit. As the drug war heated up, workplace testing did too. By the late 1990s employers started to question the cost/benefit of drug testing. Numerous studies— namely one done by the ACLU— revealed that marijuana use isn’t actually a signal of poor performance. At least not more so than the legal drug, alcohol. This supported the experience of the employers themselves who were spending significant sums of money to have the testing done. It still exists today for the reasons mentioned above."
]
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[] |
[] |
[
[]
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7d3woq
|
How is it possible that the planet Mercury gets so cold and so hot on opposite sides? Shouldn't heat conduction make the entire planet roughly the same temperature?
|
askscience
|
https://www.reddit.com/r/askscience/comments/7d3woq/how_is_it_possible_that_the_planet_mercury_gets/
|
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"There arent enough particles in the atmosphere to transfer the heat through. And with minimal atmosphere, there are also no wind currents to act like a big convection oven like we have here on earth. The heat simply doesnt spread, it radiates off slowly into space.",
"Think of the earth as a counter example. The average temperature of the earth is 3000-5000 degrees Celsius if you take the entire volume into account. Conduction through rock obviously isn’t sufficient to bring the temperature of the crust anywhere close to the average. If temperature isn’t homogenous on earth, why should it be on Mercury? The reason the earth has a relatively stable temperature at the surface isn’t due to conduction, which is slow and local, but because of convection in the atmosphere. Weather carries energy around the globe and stabilizes the temperature. Mercury, with a much thinner atmosphere, gets a full blast of unfiltered sun in the day, and has little to hold the heat in at night, Hence the huge temperature swings as radiation moves more freely, both in and out of the planet.",
"As pointed out already, the earth's atmosphere is a factor as well as rock's poor ability to transfer heat. A couple other significant pieces of the puzzle are the oceans, ocean currents, and the length of the day-night cycle. The earth's tilt helps even out temperatures too. \n \nThe faster the day, the more it evens things out. Mercury's day is pretty long at 58 earth days. If it was 10 hours, the difference in temp between the max and min would be much less. \n\nOcean currents keep Europe warmer through the entire winter than it otherwise would be just basted on how far north Europe is. In general, just like air currents, it helps even things out. \n\nWater in general has a tremendous ability to store heat in summer and give it off in winter Northern lakes are \"warm\" well into fall, past the point that the days are the longest around June 21. And frigidly cold in June even if the air feels like a hot summer day. "
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3emp3e
|
why, when we look at younger people, do we perceive them as looking younger than us than we did at the same age. (aka me at 16 looked much older than whoever is 16 right now)
|
explainlikeimfive
|
http://www.reddit.com/r/explainlikeimfive/comments/3emp3e/eli5_why_when_we_look_at_younger_people_do_we/
|
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"That's an opinion based thing. If I look at pictures of when I was 16, I look like a little kid. Then again 16 year olds also look like kids to me. Your perception of how people look changes with your age.",
"When you look at a face, your brain automatically starts categorizing and analyzing based on age, gender, race, familiarity, etc. However, when categorizing age we don't have a \"18-24\" category and a \"25-32\" category but more of a \"this person is much younger [than me]\" \"this person is a little younger [than me]\" \"this person is much older [than me]\" type of scale. Which makes sense - in your every day social interactions usually relative age matters more than absolute age, so it's good to be able to guage that at a glance.\n\n\nSo you thinking everyone under 20 looks 12 is just your brain's way of signalling \"Hey, all these people are way younger than you!\""
]
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[] |
[] |
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[],
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212yx7
|
why is our vision tinted blue after we face the sun with our eyes closed?
|
explainlikeimfive
|
http://www.reddit.com/r/explainlikeimfive/comments/212yx7/eli5_why_is_our_vision_tinted_blue_after_we_face/
|
{
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"text": [
"Detecting light requires chemical reactions inside the cells of your eye. The chemicals take a moment to reset/replenish before you can detect the light again. When you look at a bright light, it uses up these chemicals quickly, that's why you get momentarily blinded when looking at a bright light for a second. With your eyes closed, you only see the red light filtering through your eyelids, and you become red-blind, leaving mostly blue detectors working just fine.",
"You have two types of cells in your retina -- cones and rods. Rods are like a black and white camera that is really good at seeing in low light, but doesn't give you good color or fine details.\n\nThen you have cones. You have three (usually) types of cones that each detect a color of light -- red, green, and blue -- so that when the three are mixed together you get full color vision.\n\nThe cone cells get tired if they're always being activated by light, so they stop firing so rapidly after a while. Sunlight is a mix of many colors, but when you close your eyes, you filter out all the blue/green colors and just leave the red. So all the cones that are sensitive to red light get tired and stop firing as much, so that when you open your eyes again, the blue/green cones are much more sensitive in comparison to the red. This makes your vision look bluer than it normally is.\n\nThis is called retinal fatigue. "
]
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ks9qq
|
on my home theater system why are action sequences so thunderously loud but people talking barely audible. is it my setup or the film audio track itself?
|
explainlikeimfive
|
http://www.reddit.com/r/explainlikeimfive/comments/ks9qq/eli5on_my_home_theater_system_why_are_action/
|
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"Try bumping up the gain on your center channel. ",
"It has to do with dynamic range compression, or in your case, lack thereof. Movies are usually less compressed than tv shows, so there is a greater difference between loud and soft sounds. There is usually a setting on receivers and dvd players to increase/decrease this.",
"Try bumping up the gain on your center channel. ",
"It has to do with dynamic range compression, or in your case, lack thereof. Movies are usually less compressed than tv shows, so there is a greater difference between loud and soft sounds. There is usually a setting on receivers and dvd players to increase/decrease this."
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8fhror
|
How did the British view their Australian and New Zealander soldiers?
|
Did they respect them as soldiers or did they see them as cannon fodder and inferior to actual British soldiers?
|
AskHistorians
|
https://www.reddit.com/r/AskHistorians/comments/8fhror/how_did_the_british_view_their_australian_and_new/
|
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"What time frame are you asking about? "
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qmt43
|
why do we have war, and why do we go to war?
|
If it helps, my son who asked was 7, so feel free to explain it like I'm 7.....my son came to me last night and said "Dad, why do we have war, why do people want to kill other people?" Immediately i thought, religion, greed, and just straight up bad guys. I had no idea how to relay that to him so that he would understand, to be honest, I still struggle to grasp how even though I know that religion, greed, and bad guys in power are the reasons, and I know that war is necessary sometimes....but why do we as humans create these situations. I guess I'm looking for a scientific reason why humans go to war.
|
explainlikeimfive
|
http://www.reddit.com/r/explainlikeimfive/comments/qmt43/why_do_we_have_war_and_why_do_we_go_to_war/
|
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"Pick up a copy of Marvin Harris' book \"Our Kind\". It is an anthropological reader aimed at the masses, and your son should be able to make it through most of the topics. War is included from an anthropological perspective. \n\nFor my own opinion, not Marvin Harris': War is all about resources. The have not want what the haves have, as it were. This continues to be true until a culture grows beyond the point of being ruled by a single person, at which point war becomes more and more a means of entertaining and controlling your own people - so you can have more resources yourself. ",
"Resources. Without resources we die. ",
"That is less of a scientific question and more of a philosophical one. \n\nUltimately there is no real scientific reason we go to war, it's not a physical necessity. \"religion, greed, and just straight up bad guys\" may be things we fight about, but it's not **why** we fight.\n\nHumans are born with the innate ability to be violent, it does not have to be taught. As we grow, all of our abilities are advanced, this includes our ability to fight. As we get older, we stop fighting by ourselves and get others who we like to fight with us against the guys we don't. That is the progression of war.\n\nPersonally I don't think that with a 7 year old you don't have to get more complicated than \"there are bad people who will try to kill others when they have arguments\". It's not necessary for them to understand at a deeper level at that age, when they are able to properly process that type of information, then it will be more obvious to them. \n\nIf you want my personal opinion, I believe that war is just another sign of intelligence. No other species can fight as effectively as we can. \"It's what humans do\" is kind of a cop-out answer, but it's still very true. \n\n\"why do we as humans create these situations?\" We create these situations out of the fact that we are individuals and simply do not agree on some things. \n\nI think it is a difficult thing to explain, \"we argue, therefore we fight, therefore we kill, therefore we have war\". There is no simpler explanation.\n\n",
"War is the last resort to any situation which can't be settled. Let's say there's a land boundary dispute between North and South Dakota. We could try some sort of treaty to resolve the dispute, but we can't come to a conclusion. It's taken to court. The court rules for the North. But this pisses South off very much. The appeal in court but the result stays the same. \n\nYou could try many different methods to settle a dispute like this (a sporting event challenge, random drawing, a vote, etc), but in the end, there's always one last resort... Violence and war. If you have no one else to argue with, you win.",
"\n\"Naturally the common people don't want war: Neither in Russia, nor in England, nor for that matter in Germany. That is understood. But, after all, IT IS THE LEADERS of the country who determine the policy and it is always a simple matter to drag the people along, whether it is a democracy, or a fascist dictatorship, or a parliament, or a communist dictatorship. Voice or no voice, the people can always be brought to the bidding of the leaders. That is easy. All you have to do is TELL THEM THEY ARE BEING ATTACKED, and denounce the peacemakers for lack of patriotism and exposing the country to danger. IT WORKS THE SAME IN ANY COUNTRY.\"\n \n--Goering at the Nuremberg Trials",
"War is an extension of politics. Basically, countries enter into a war to achieve a political end, whatever that may be, and will only do so if the war itself does not subvert that political end.\n\nHowever, this does assume the leadership of the countries involved are rational."
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1adoum
|
why do some (ebay) auctions have "reserve" prices?
|
What is the purpose behind a reserve price on an ebay auction? I understand that it sets a minimum amount to win the auction but why doesn't the auctioneer just start at the reserve price?
|
explainlikeimfive
|
http://www.reddit.com/r/explainlikeimfive/comments/1adoum/eli5_why_do_some_ebay_auctions_have_reserve_prices/
|
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"Starting at 0 entices buyers to begin bidding and then once they've started they will keep bidding past a point when they may have begun bidding earlier.",
"I think it also gets the bidding ball rolling and taps into peoples competitive spirit. \nSomeone is more likely to arrive at $150 trying to outbid their auction 'competitors' than if the bid started at around that price. "
]
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|
2gtjqf
|
How different are h.sapiens from today vs 1 mya?
|
How different would an early Homo sapiens be from a Homo sapiens from today? Could one survive easily in the others timelines? Immunity to diseases would definitely be a concern. What else???
|
askscience
|
http://www.reddit.com/r/askscience/comments/2gtjqf/how_different_are_hsapiens_from_today_vs_1_mya/
|
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"Well, we only diverged from neanderthals around 500,000 years ago. So 1mya we would not be looking at h.sapiens exactly. That said I am interested in hearing more from someone who studies this and so knows more than me.",
"Language probably does not predate a critical mutation of the FOXP2 gene, estimated around 100,000 years ago, IIRC. Mutations of the gene in mice lead to more vocal individuals. Conversely, disruption of the unique human mutations causes inherited language difficulties.",
"Thanks for all the great insight and comments...sorry if my timeline was off by a few hundred thousand years (what's a few thous. yrs between redditors)...what I was really was trying to ask was how physically/anatomically/biologically different a modern Homo sapiens would be from a dawn of species Homo sapiens?"
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2zgjku
|
Why does it take longer to get dark at night in some areas over others that are along the same or are close in latitudes?
|
I live in Edmonton, which is pretty well a mid prairies city, and have noticed that in the summer, it takes a really long time at night before it get a dark,even well outside the city. For example, the sun may set at around 9ish, yet it won't get dark until nearly midnight, while in Toronto, or San Jose which is much further south, it'll be dark within a half-hour or hour of sunset. Why is that?
|
askscience
|
http://www.reddit.com/r/askscience/comments/2zgjku/why_does_it_take_longer_to_get_dark_at_night_in/
|
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"Twilight lasts a longer time the further you get from the equator, because the Sun moves at an increasing angle to the horizon. The extreme case is the polar regions ( > 66 degrees from the equator), where the Sun never sets at all during summer, while at the equator it sets essentially perpendicular to the horizon, so it goes down fast.\n\nEdmonton (latitude 53.5) is about 10 degrees closer to the pole than Toronto, and 16 degrees closer than San Jose. This makes a big difference.\n\nAlso, the Sun is not so far below the horizon at midnight, only about 13 degrees at Edmonton in mid-summer, versus 29 degrees in San Jose.\n"
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638iq2
|
how did humans develop such that a well balanced human diet consist of a wide variety of foods when throughout most of human history we only had access to a few foods?
|
This seems like it'd doom our survival as a species.
|
explainlikeimfive
|
https://www.reddit.com/r/explainlikeimfive/comments/638iq2/eli5_how_did_humans_develop_such_that_a_well/
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"Eating sub optimally does not mean a swift certain death. It means a slightly lower quality of life (think of how you feel from a week of eating fast food vs a week of eating healthy), deteriorating more quickly (your brain may slow down faster as you age), a slightly higher risk of developing disease, etc.\n\nGood nutrition is just maximizing your optimal health, not something as polarizing as going from dying of every disease at 20 vs living forever.",
"A 'well balanced diet' is, in part, a fabrication from the advertising departments of food companies. Think \"this bowl of Fruit Loops is part of a balanced healthy breakfast\" \n\nAlso, consider that a lot of modern processed food lacks the overall nutrition of whole natural foods. \n\nSo if someone's diet consists largely of nutrient poor processed foods, then they really should try to 'eat a balanced diet'. But a diet of whole/natural foods will be more balanced by default. \n\nIt's been popularized as the paleo diet. ",
"Grains, roots, leafy vegetables, fruits and meat were all available in the environment in which humans evolved. Agriculture provides more dependable food and selective breeding makes it more palatable. Except in areas of overpopulation, drought or war, a varied diet is and has been available.\n",
"It's not that the body evolved to need a well balanced diet- we humans can survive on pretty unbalanced food just fine.\n\nWhat a well balanced diet is is that we have discovered that certain food combinations optimize the nutrients that out body gets.\n\nThink of your body like a car, food is fuel, you can put pretty much any gasoline in your car as fuel. But, you know, some gasoline works better in your car than others, some leaves buildups that make the car run worse, some contain additives that help keep the engine cleaner, and there are different octane levels that, while they can all technically burn in your car, often there is one specific one that is best suited to being used.\n\nTL;DR: your body can get by on a lot of things, and the well balanced diet is less a requirement of your body than the result of a lot of trial and error trying to figure out what is most optimal to eat.",
"No one really answered this for you they just talked about diets so let me give it a shot. \nUntil recently the world was a large place with many isolated groups of people who would pick what foods could sustain them by their region. \nOnce regions were colonized and trade began, food options for those who benefitted from the trade increased. \nThousands of years for isolated groups to determine what suits their needs best per region then becomes a global buffet from trade. \nAnd like people and culture who make steps forward and back due to war, famine and natural disasters so does the food. \nAnthropologists often argue that new (past 100 years or so) mass agricultural techniques has limited our food diversity, with many plants and animals going extinct. \nAnd I doubt that will change much with Monsanto's great ideas for seed regulation and GMOs. ",
"Hunter/gatherer societies lived on an incredibly diverse diet, sometimes upwards of 70+ different fruits/grains/roots. Millions (billions) of people living off of wheat/rice/potatoes/corn is relatively new in the grand scheme of things ",
"You're looking at it the wrong way. Think of animals as complicated machines that can run on a variety of fuels. We can live long(ish) healthy(ish) lives in all kinds of environments, during all kinds of climates. We're adapted for versatility and survival.\n\nBut we've reached this point where, due to the intricacies of civilization, we can have very nearly ANY food that we want. So now we're in the middle of trying to figure out what combination of food is the very, very, very best for us. We could survive just fine living only on what we can grow and kill in a twenty mile radius of where we are right now (okay, not everybody can, but a surprising number of people could), but that isn't the question anymore. The new question is: what is OPTIMUM. And to figure that out, we can take a look at all of the people all over the world and start asking: which people have the best X and why is that? Who has the healthiest skin? Is that because of the sun? The atmosphere where they live? Genetics? Or something that they eat? And how can w spread whatever causes that great skin to everyone in the world?",
"We evolved to eat as little as possible to survive and reproduce. Reproduction is the measure nothing else. If it doesn't contribute to survival and reproduction it is irrelevant. In fact evolutionarilly living a very long time isn't actually ideal since you are not reproducing and might not even be contributing.\n\nToday we really care about living a long life, living to your 50s is considered dying really young. Back in older times 50s was a pretty good age to reach! You may very well be seeing your grand kids or MAYBE even great-grandkids!",
"History, being the part of the human past that has been written down, is not that long. When you consider that the human digestive system has been evolving for millions of years, a few thousand is relatively small. In fact, the diet you are likely most familiar with is very uncommon throughout Homo sapiens' past. \n\n\nIn prehistory, the human diet was much more widely varied than it is today. Hunter/gatherers had to range far and wide to get the foods they needed to survive. It wasn't until a period known to archaeologists as the [neolithic(new stone age) period](_URL_1_) that humans began to narrow their food sources with agriculture(5-10k years ago) and a more sedentary life. The period is named this way because we find stone tools used for processing large quantities of grains associated with the time period. The most common of these are known as [manos and metates](_URL_0_).\n\n\nedit:spelling",
"There are a number of issues with the question/premise.\n\nA \"well-balanced diet\" is largely a nutrition science idea, and even the best nutrition science is still rather limited. There are a huge number of things about food that we don't know - it's actually a pretty complex subject. \n\nSo, what determines a \"well-balanced\" diet? If we're talking what makes people feel the best (energy, good sleep, etc.) and have the best medical markers of health (low blood pressure, low cholesterol, healthy weight, good lung capacity, good heart rate, etc) it's still likely to vary. Part of it is likely biology. We're just now learning more about how different cultures actually may extract different amounts of nutrients from the same food. (Asians vs. Caucasians eating seaweed for example, or being able to process soy products better.)\n\nBut even just, what works for your body? Some people swear by low carb, for example. I have no energy and am super cranky if I try low carb. \n\nLastly, \"well-balanced diet\" is not remotely necessary for survival. Arguably, a lot of people on a \"western\" diet don't eat \"well-balanced\" in any of the typical accepted versions of the term. Too much sugar, too much over-processed food, etc. But it's not necessary to eat a well-balanced diet simply to *survive.* You can survive in a lethargic state, in a tired state, with high blood pressure or cholesterol, etc. In fact, a lot of us *are* surviving in that state. It's not desirable, IMO, but it's happening.\n\nThe rise of \"western\" diseases like diabetes, hypertension, heart attacks.. a lot of these are diet-based, but it's not because we're trying to \"diversify\" or have a \"well-balanced\" diet. It's more likely (from what evidence we do have) the result of the *type* of diet we're consuming. The extra processed junk, the massive amounts of sugar, things like that.\n\nHumans by and large can survive on a wide range of diets, and even be pretty healthy on a lot of them. The idea of a \"well-balanced\" diet is science trying to figure out what it hasn't yet been able to solve. \n\nCheck out Michael Pollan's work on nutrition, like In Defense of Food. It's pretty fascinating stuff, tracking the rise of government food pyramids and the removal of \"imitation\" labeling, the anti-fat craze that was not medically backed, and a whole lot of looking at other cultures throughout history, and what they ate.\n\nIt's really interesting.",
"Our ancestors had access to more foods than you think. Just not all at once. As recently as the 19th century in northern climates during the winter fresh foods were reduced to things like potatoes, apples, carrots, and cabbages that would keep all winter. When spring came they were hungry for fresh food. Rhubarb is the first thing to come up, and stewed rhubarb was considered a tonic. Then all summer peas, beans, tomatoes, etc were eaten as they became available.\n\nMeat and fish were also available seasonally. So during the year they ate a varied diet as things came in and out of season.",
"We as a species have always retained a pretty high diversity of foods in our diet. If anything, we would likely not have evolved if it weren't for the ability of our hominid ancestors, specifically H. erectus, to cook and process food. There is a theory in evolutionary anthropology about the relative balance of the gut and the brain, sometimes referred to as the gray ceiling. The idea being that both the digestive tract and the brain are biologically \"expensive\" organs requiring lots calories to do their jobs. When H. erectus developed cooking anywhere from 750kya to 1mya, hominids suddenly gained the ability to get much more out of their foods, nutritionally speaking. Cooking and food processing made digestion easier, allowing for the greater extraction of nutrients, and allowing for the gradual increase in size and neural convolution of the hominid brain. If anything we have required dietary variation for our development as a species and to maintain the calories to support our complex brains.\n\nBy about 250kya, H. Sapiens appeared on the world stage, and by 20kya, we had developed agriculture. There has been lots written on the downsides of agriculture, especially as it pertains to overall health of localized human populations (the prevalence of dental caries in Native American populations really sticks out in my brain), but let's not lose sight of the forest for the trees: except in certain instances of localized population collapse due to crop failure, agriculture has been a huge net positive for human as a species. Agriculture has crucially provided us the ability to have a readily available source of high calorie foods and as such has supported the development of both cities and civilization as we understand them today. Even though the relative diversity of foods may have declined as groups developed crop specialization, humans have always required multiple food sources for proper nutrition and survival. While there is clearly a plethora of literature available evaluating the role of famine in causing local population collapse, the idea that humans as a species would subsist solely off of a single food source is a bit of a misconception. The Native American groups of the Southwest subsisted on more than just maize. Unless there were extreme circumstances affecting a localized population, such as a natural disaster or crop collapse, humans have always sought out food diversity by supplementing major crops with other vegetables, adding protein to their diet through animal meat and/or milk, and by trading with other groups for other types of food. This has been the ultimate key to our species' success.\n\ntl;dr--While agricultural development created a sort of dietary bottleneck, it has never been so extreme as to cause a species-wide population collapse. In actuality, the ready availability of calorie dense food brought about by the development of agriculture far outweighed any nutritional deficits on a species wide scale and ultimately led to rapid population growth.\n\nSource: Masters in Biological anthropology/human skeletal bio",
"It's just not true.\n\nNatural human diet is a really low-calorie one. Some people can live a decent life with 60gr of rice a day (250 cal/day).\n\nThe problem is the american 2000 cal/day diet. Without variety, it kills you.",
"Since all humans on earth began as hunter gatherers, there was really no need for major food production or farming. The thought process of most early hunter gatherers began with preferences to what is available around them. Back in the late Pleistocene hunter gathers were still active because wild animals were abundant. Thus yielding more calories and higher reward than farming or domesticating wild edible plants. However, if we look at the Fertile Crescent which began major food production around 8,500 BC, we can see that a big factor in domestication and farming of local native plants is the advancement of farming technology. We see flint sickles, woven baskets, tools for grinding cereals and breaking husks, and even the process of toasting edible seeds so that they do not sprout in storage. With the advancement of food production came an increase of population density. There is a correlation between farming and population density. With more population there are more people to work. This allowed people to focus on farming and others to focus on the other necessities of a community. With that also came trade. In this sense the trade was founder plants that could be taken to other parts of the world to begin a variety of available goods. For example, around 2500 B.C. Southern Native Americans traded with Mexican Indians (who had an efficient system of food production) and began growing new crops such as beans and corn. All of these processes began a cycle that leads us to the availability of a wide variety of foods and goods. ",
"You're looking at it backwards. It's not that you have to have dozens of foods or else you die. It's that you can survive off of many different types of diets, and still keep going. Sure, you're at your best when you have a varied diet, but that isn't always required.\n\nThis is very different than something like a Koala, which can ONLY eat eucalyptus leaves, or a panda that can ONLY eat bamboo. \n\nMost animals require foods that are only available in certain types of ecosystems. Humans on the other hand, have evolved the ability to survive in EVERY ecosystem.",
"Before humans settled down and started growing their own food, they ate a much wider variety of foods. They also were much healthier. They ate hundreds of different plants and animals on a regular basis, compared to a few dozen at most for much of agricultural history. Pre-agriculture humans were taller on average than humans are today, and had considerably less tooth decay than humans have for most of history since. They also didn't have the sort of repetitive stress injuries that their agricultural descendants got from grinding seeds into flour for hours on end. \n\nThat said, the humans that didn't settle down and accept crappier health outcomes were never able to accumulate much stuff, or develop much advanced culture, or develop advanced weapons and other technology like their agricultural cousins. The difference in capabilities was so great that the agricultural humans could just march in and take the land that the hunter-gatherer humans were living on, and the hunter-gatherers couldn't do anything about it. Not only did they not have the technology, but they didn't have the numbers, since agriculture allowed for much higher population densities.\n\nTL;DR: Adapting to eating fewer types of food was good for the survival of the community, but bad for the survival of the individual.",
"Why do you think humans only had access to a few foods? Humans had access to a wide variety of foods, such as animals, fish, mollusks, fungi, fruit, root vegetables, various herbs, wild grains, LOTS of stuff. ",
"Organisms that can eat a wide variety of food are more likely to survive, reproduce, and pass on those omnivorous traits.",
"Copied and changed a comment I made lower down. We ate primarily plants, roots, tubers, etc. were staples. Hunter gatherers, depending on location, are traditionally about a 70/30 split between plant matter and meat. I think you're also making the assumption that the most of human history has been post agriculture. Humans were primarily hunter gatherers for longer than we've been farming. \n\nHumans ate literally everything that was edible. Before, the rise of civilization hunter gatherers had access to the best environments, which is where people typically settled pushing out the surrounding people as it expanded and biomes were changed by farmland. That meant that we weren't just eating roots and tubers, but wild onions and other \"precursor\" plants to common fruits and vegetables of today, as well as lots of leaves and natural herbs which were packed with nutrition. \n\nA typical hunter gatherer group would stay in a particular spot for a short amount of time until they exhausted most of the easy food, depending on need of course, for a few miles around. Then they move to a new spot outside of their foraging range and stay there until there isn't easy food. This could be as short as a few days if they're on the move to weeks/months at where they spend the spring/summer months, all depending on location. This means that they might subsist on one particular plant for a little while as a staple, with other little things being thrown in. Then move to a new area with a slightly different diet/move entire regions if they migrate. This means that we needed to be able to live on a large variety of food types and this constant moving meant that most diets weren't just one food and people didn't become deficient in things because of variety. It wasn't until people became sedentary and the agricultural revolution happened that people began subsisting on a few food sources year round and chronic deficiencies became a real problem. \n\nYes people lived longer, grow bigger, and support a bigger population because of more food but there's times in our history, medieval Europe for example, when the peasants were in worse condition than you would find in a stable hunter gatherer society. It was due to this evolution of being able to subsist on one particular food as a staple for months at a time that allowed people to live on several staple crops year round. Due to our nomadic nature we have to be very flexible in our diet and that has also led our bodies to be able to compensate when it runs into deficiencies.",
"What do you mean by \"balanced diet\"? I survive on cookies and peppermint tea. They're kinda hard to balance.",
"What do you mean we only had access to a few foods? Nature is bountiful, take any ancenstral human and Im sure they had access to a wide variety of food. Name any ancient human anywhere. ",
"There are some very good answers here, but not all of them address a common misconception:\n\nThere's no such thing as an essential food. Only essential nutrients. Your body doesn't care where the nutrients come from, only that it gets at least a little bit of each of them regularly. Most deficiencies that cause health problems don't set in for several weeks at least, so unless you're eating nothing but Doritos, you're probably getting trace amounts of all the essential nutrients from many sources.\n\nAnd there are even a few foods that contain a wide enough variety of nutrients, albeit in small quantities, that can sustain you almost indefinitely. Look at the Eskimos. They survive on almost nothing but whale and seal blubber for 8 months a year, with virtually no plants in their diet at all. It's basically pure fat, that's high in protein and calories, and very low in everything else. But they *can* survive on it because the blubber contains just enough of all your body's required vitamins and minerals to stave off severe deficiencies like scurvy (absence of vitamin C).",
"since when did we develop a well balanced diet? it seems like every few years scientific advice for a proper diet changes. I'm pretty sure being a dietician isn't even a real job.\n\nI've given up trying to figure out what to eat properly, because its just too much of a headache to find undisputed information. also we are fucking up the planet so much even healthy food like tuna needs to be moderated because of mercury levels. these days i just eat what i feel like and also try to eat so i feel good the next day as well. and I can go for a run or play sport without feeling sick.",
"Wait what? Before modernisation of human society you couldn't swing a soft juicy prey animal without discovering 3 new species of edible plants. We are currently living in the most narrow band of food options. Ever."
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2zeuwu
|
Was Greek almost the official language of the United States?
|
My roommate and I were talking, and he brought up that Greek was 1 vote shy of being the official language of the US. Apparently Ben Franklin was the swing vote and voted for English. I just want to know if there is any truth to this.
Also, sorry if this was asked before, it's my first time on this subreddit.
|
AskHistorians
|
http://www.reddit.com/r/AskHistorians/comments/2zeuwu/was_greek_almost_the_official_language_of_the/
|
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"tl;dr so essentially we had a vote to decide to print laws in German as well as English and it's possible utopians may have advocated making Greek Latin or French an official language (\" considered in the late 18th century to be the languages of God, rationality, and democracy, respectively.\") but there would have been nowhere near any sort of majority in support and a vote for that never happened.\n \n\nI want to step back from the direct question and provide some historical context for the Mulhlenberg legend and the idea people proposed greek as the official language of the US since both are based on actual historical events. \n\n1. greek proposal [The Marquis de Chastellux] (_URL_1_) was one of the liberal french nobles who went to america to support the revolution and was in the Académie française. Serving in Rochambeau's staff (be glad you don't have to read that guy's handwriting) he struck up a personal friendship with washington and in his letters he mentioned [some were proposing using Hebrew](_URL_3_) as the national language\n\n > the proposal was, that it should be taught in the schools and made use of in all public acts. We may imagine this project went no farther but we conclude from the mere suggestion that the Americans could not express in a more energetic manner their aversion to the English.\n\nSimilarly 19th century american [Charles Astor Bristed](_URL_2_) appears to have made the claim that people were proposing Greek be the American language causing Roger Sherman to make a famous quip (see below)\n\nthe best claim for a direct quotation of the work i can find follows:\n\nThe American scholar and author Charles Astor Bristed wrote in 1855: “It is still on record that a legislator seriously proposed that the young republic should complete its independence by adopting a different language from that of the mother country, [like] ‘the Greek for instance.’ But this proposition was summarily extinguished by a suggestion of a fellow representative (Roger Sherman of Connecticut, delegate to the Continental Congress and a member of the committee that drafted the Declaration of Independence) that ‘it would be more convenient for us to keep the language as it was, and make the English speak Greek.”\n\nI can't actually find a source before Bristed for the quote or event so it may be apocryphal. \n\n\n2. the Mulhlenberg legend:\n\n_URL_0_ (going to cite a good chunk from this)\n > In April, 1987, an election judge from Missouri wrote to Ann Landers citing the following excerpt from the local Election Manual to support the argument that everyone's vote counts: “In 1776, one vote gave America the English language instead of German.” The statement is not strictly true, as many of Landers' more alert readers quickly pointed out...On January 13, 1795, Congress considered a proposal, not to give German any official status, but merely to print the federal laws in German as well as English. During the debate, a motion to adjourn failed by one vote. The final vote rejecting the translation of federal laws, which took place one month later, is not recorded.\nThe translation proposal itself originated as a petition to Congress on March 20, 1794, from a group of Germans living in Augusta, Virginia. ...the Aurora Gazette[:] “A great variety of plans were proposed, but none that seemed to meet the general sense of the House” (22 January, 1795, p. 3).\nA vote to adjourn and sit again on the recommendation failed, 42 to 41, but there is no reason to believe from this close vote that more than token support existed for publishing the laws in German. The vote to adjourn seems to have been interpreted by the House as a vote of no confidence both in the committee's recommendation to translate the laws and in its recommendation on the distribution of the sets of laws once they were published in English...if sentiment on the issue in Congress was anything like sentiment in Pennsylvania, translation was probably opposed by a substantial majority of the representatives...\nOne month later, on February 16, 1795, the House once again considered the question... This time some of the actual debate has been preserved [see site]\nThe January vote on adjournment is sometimes known as “the Muhlenberg Vote,” after the Speaker of the House of Representatives, Pennsylvania's Frederick Augustus Muhlenberg, a Federalist who spoke German with difficulty, so it is claimed, and who was at any rate a member of a prominent family of assimilated Germans...tradition has it that Muhlenberg stepped down to cast the deciding negative, thereby dooming German in America to minority-language status [but we don't have the roll call]...\nNonetheless, Muhlenberg was blamed for selling out German language interests by **Franz Lher, whose 1847 History and Achievements of the Germans in America** presents a garbled though frequently cited account of what is supposed to have happened. **Lher places the crucial language vote not in the U.S. Congress, but in the Pennsylvania legislature, over which Muhlenberg had earlier presided.** ... However, Muhlenberg later did manage to irritate his German constituents by casting the deciding vote in favor of the Jay Treaty during the Fourth Congress, a move which drove his brother-in-law to stab him and which cost him the next election in 1796. This significant tie-breaker soon became confused with the earlier adjournment cliff-hanger, conveniently fleshing out the myth of the German vote (Feer 1952, 401). \n\nthe bold portion highlights where i think Ben Franklin got brought into this false narrative. A game of telephone caused Franklin, a figure everyone still knows, to replace a now obscure Pennsylvanian. "
]
}
|
[] |
[] |
[
[
"http://www.english.illinois.edu/-people-/faculty/debaron/essays/legend.htm",
"http://en.wikipedia.org/wiki/Fran%C3%A7ois-Jean_de_Chastellux",
"http://en.wikipedia.org/wiki/Charles_Astor_Bristed",
"https://books.google.com/books?id=Q28RBAAAQBAJ&pg=PA137&lpg=PA137&dq=Chastellux+hebrew+greek&source=bl&ots=CQ044jmK4K&sig=YwnTLYVD99CXr0l-tCFwGLIHtmU&hl=en&sa=X&ei=uq8JVf7xNYv1oATHoIGwCw&ved=0CC4Q6AEwAw#v=onepage&q=Chastellux%20hebrew%20greek&f=false"
]
] |
|
6ocn7w
|
how these modern tiny loudspeaker / amplifiers sound so good?
|
When I was a teenager you needed huge loudspeakers and a 40W amplifier to get decent bass plus a tweeter for the top end. What magic is at work here?
|
explainlikeimfive
|
https://www.reddit.com/r/explainlikeimfive/comments/6ocn7w/eli5_how_these_modern_tiny_loudspeaker_amplifiers/
|
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"text": [
"I know part of this, much stronger permanent magnets. Back then we didn't have neodymium magnets, utilising those in speakers allows for much more powerful motion of the speaker cone so you can get much louder and better sound from a smaller speaker with less power supplied to the coil. \nI'm 37 and I'm also really impressed at the quality and bass you can get from these tiny speakers you can plug into your phone or whatever. I wish we had them in the 90s. "
]
}
|
[] |
[] |
[
[]
] |
|
5jdc2o
|
Is there a usage of quantum physics in our body?
|
askscience
|
https://www.reddit.com/r/askscience/comments/5jdc2o/is_there_a_usage_of_quantum_physics_in_our_body/
|
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"Maybe. Known quantum effects in biology include long-range coherence during photosynthesis and [the magnetic field detection that birds use to navigate](_URL_0_). It's possible that [smell uses quantum effects](_URL_1_) to identify individual molecules, but from what I've read this is still a speculative hypothesis. There was a [recent paper](_URL_2_) arguing that entanglement of phosphorus in the brain is responsible for cognition, but this is not accepted.",
"Cytochrome P450 enzymes are thought to use quantum physics to control chemical reactions! _URL_1_ All forms of life produce Cytochromes for important metabolic reactions. These proteins fold so accurately they can hold molecules and distort the electrons to warp quantum spin. They can so effectively hold electrons in the proper state, that the speed of their chemical reactions cannot be explained using traditional physics!\n\nThis lightning fast reaction speed, is how these effects were first observed. A result of quantum tunneling _URL_0_. ",
"Chemistry is just quantum mechanics. Bonding, activation energies, etc. All QM"
]
}
|
[] |
[] |
[
[
"https://arxiv.org/pdf/1204.6528.pdf",
"http://aip.scitation.org/doi/full/10.1063/1.4767067",
"https://arxiv.org/pdf/1508.05929.pdf"
],
[
"https://www.ncbi.nlm.nih.gov/pubmed/19480428",
"http://www.columbia.edu/cu/chemistry/groups/berne/papers/jacs_126_8501_2004.pdf"
],
[]
] |
||
2uaybp
|
why don't they use metal detectors before an mri scan?
|
I've seen in TV shows that any ferrous metal in your body can be extremely dangerous during an MRI. I had an MRI recently, they made me sign that I don't have any of that, but that was it. Why don't they have, say, the same equipment TSA uses in airports? Is it too expensive or not sensitive enough?
|
explainlikeimfive
|
http://www.reddit.com/r/explainlikeimfive/comments/2uaybp/eli5_why_dont_they_use_metal_detectors_before_an/
|
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"I think it may just be an unnecessary expenditure since you are assumed to know if you have metal in your body, or it would at least be present in any medical records or be in there for some plausible known reason. ",
"Section 2.4-3.4.4.2 of the [FGI Guidelines](_URL_0_) requires \"ferromagnetic detection systems\" in use at access points to MRIs.\n\nHowever, this clause was added in 2010, and does not affect installations built before that time. Additionally, not all states require hospitals be built to the FGI guidelines, and some only require part of them. \n",
"I've got 2 plates and 12 screws in my ankle and my biggest worry is that I'll be in an accident and get knocked out and they'll put me in the mri and the hardware will get ripped out of my ankle ",
"There are some situations where xrays are performed before an mri is done. Example, if there is a chance you have shrapnel of any sort in your body, an xray is usually performed prior to check for this metal. This is speaking of an out-patient scenario. In trauma scenarios, xray or CT is the preferred choice due to the length of exam for CT vs MRI. ",
"They have them on hand if there is any concern. For example, I once had a serious head injury and couldn't remember where all of my piercings were. I was headed in for an emergency MRI, and they scanned me with a handheld metal detector. \n\nUnder most circumstances though, a person knows where metal in his body is located. And for surgically placed metal implants, they use a type of metal that is safe in an MRI",
"MR techs know which implants are safe or unsafe in the MR environment. There is rigorous testing on implants and they refer to that literature. You fill out a form before your test to tell the tech what is in your body. If you are unsure about metal in your body, they assume you are unsafe and proceed accordingly. This may involve an x-ray to see if there is metal in sensitive areas of your body.\n\nAs /u/ChildoftheFence19 said elsewhere in this thread, most implants are safe after being in your body for 6 weeks. As you heal, scar tissue builds up around the implant which anchors it in place and prevents localized heating. This is true for small surgical clips to large prosthetic joints. \n\nAs for why they don't use metal detectors, my assumption is that they aren't sensitive enough. All they'll do is beep if there's metal present but they can't distinguish between safe and unsafe metal. At that point, the tech would have to ask you all those safety questions and decide how to find the information you're unsure of. So having the detector just adds steps to the process unnecessarily."
]
}
|
[] |
[] |
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[],
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"http://www.fgiguidelines.org/pdfs/FGI_2.4_CriticalAccess_Hospitals.pdf"
],
[],
[],
[],
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] |
|
2g5vlc
|
Cold weather and lung disease - how are they linked?
|
For me at least, being somewhat sweaty (perhaps hot too) and stepping outside in cold weather is a guranteed recipe for getting a severe cough. What exactly is the cause of this lung "infection"? It is often very severe for me and lasts for several days!
|
askscience
|
http://www.reddit.com/r/askscience/comments/2g5vlc/cold_weather_and_lung_disease_how_are_they_linked/
|
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"This is pretty much asking for medical advice. You should go see a doctor.\n\nThere is a reflex that makes you cough a bit upon moving from warm air to cold air, but it's not severe and it does not last days.",
"There's really no link between being cold weather and the common cold, unless you actually develops hypothermia, which leads to a weakened immune system. \n\nThe confusion, and what you may be describing, arises from people who have cold and exercise induced asthma. You should see a doctor."
]
}
|
[] |
[] |
[
[],
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|
35zxkz
|
How did contemporary, mainstream western ideas about fashion and gender develop?
|
Men's formal, professional, and casual clothing is plainer and with fewer options than women's clothing. Men also conform to laxer grooming standards, don't wear makeup, accessories, etc., and aren't criticized if they spend limited time on dressing and personal hygiene. Women, on the other hand, stereotypically wear makeup, spend copious amounts of time on their hair, have giant shoe collections, etc. There are also far more options in terms of female fashion. This is obviously tied to gender expectations and sexual/gender identity, as men who do focus on their appearances are often assumed to be gay (or that lovely '00s term "metrosexual"), whereas women who don't/choose not to conform to female norms of appearance are either lesbians or somehow incompetent women. How did this connection between appearance, clothing, and gender develop?
|
AskHistorians
|
http://www.reddit.com/r/AskHistorians/comments/35zxkz/how_did_contemporary_mainstream_western_ideas/
|
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"There was a [phenomenal answer](_URL_0_) posted a year ago in response to a similar question, and I'm not really sure it can be improved upon. James Laver is an old source for doing fashion history, but he's correct here.",
"At first I thought to break this down as a study of the changes in mens, womens, and childrens fashion starting around 1700. But, though I think the way we dress children plays a huge role in this answer I'm not sure that's the best lens to view it through. Instead, we're going to explore Ornamentation. It seems the easiest way to sum up fluff, frills, trimming, accessories and the time one has to put in to deciding, dressing, and wearing these things. With too much ornamentation men today are seen as effeminate peacocks. When women put no time into such things they are dressing overtly masculine and fall into stereotypes as well. I feel like cleanliness is a whole topic unto itself, so I'll likely skip that for now (I've been studying it a lot lately, but haven't made it into the 20th c. yet).\n\nI'm going to start with the 18th century, because that's as far back as my expertise comfortably goes (it could certainly be extended further back as a topic, but there are more than enough changes between now and then). At this point there is clearly gendered clothing. Ornamentation is also gendered, not by amount but by type. A man's coat in the early part of the century could be covered in dozens of superfluous buttons, gold or silver lace trim, and embroidery. While the buttons numbers do decrease throughout the century, they have a brief stint of massive proportions in the 1780s/90s. Even English sporting clothes, the epitome of a masculine gentleman, were not immune from such touches. [The Spruce Sportsman](_URL_0_) of the 1770s has on a practical pair of leather breeches, boots, and is even still holding his rifle. But, his fine wool broadcloth coat is adorned in gold lace and silver buttons, his hat in gold braid. A set of silver buttons from around this time survive in the Colonial Williamsburg collection with provenance to William Lightfoot. They are large, silver buttons with hunting dogs and their names engraved upon them. The cuff buttons for the coat have tiny foxes. Clearly meant to be placed upon a hunting coat similar to that in the print, ornamentation of this kind was certainly not feminine.\n\nThere are plenty of prints during the later 18th century of dandies, fops, macaronis, puppies, etc. What I find terribly interesting is that, despite their clear opinions of this sort of dress being incredibly over-the-top and even sometimes absurd, I don't find images that imply them to be \"gay\". In [Is This my Daughter Ann?](_URL_1_) you see the macaroni gentleman being affectionate with his equally grand female lover. [The Covent Garden Macaroni](_URL_9_) eyes a lovely young lady out for a walk. That's not say they didn't see them as sexually absent or stunted (perhaps just distracted) as [this Henpeck'd Husband](_URL_7_) shows.\n\nOn the opposite end of this spectrum we find the rather butch women. They too are not shown to have sexual differences based on this persona, but rather as tough, uncultured, and low-class. They're a [common pair](_URL_3_) to the macaroni, usually bullying him about. Even [well-dressed women](_URL_8_) could be found in more aggressive and masculine situations. Masculine attire for women in the form of riding habits were around earlier in the century, but really took off in the 1770s. Thoughts on this were made very clear by images of [women clomping into the print](_URL_4_) complete with men's boots and coat. If you look closely you'll even see her foot trodding upon a paper saying \"effeminancy\". Clearly, [the fight over who wears the breeches](_URL_5_) was something of a topic. But, despite all of this it seems more to do with women asserting dominance, often paired with more masculine clothing, than seeing a plain or unkempt woman as lesbian.\n\nThis feminine dominance becomes even more of an issue in the 19th century. Prior to this is was not seen as demasculinizing for the wife to work. Many women in the 18th century did so in their own trade, their husbands, or mainly working out on the farm. While the optimal idea was to have the husband working in a profession (or trade if he must) and the wife at home taking care of the time-consuming household, it seems they had the idea that two incomes are better than one the same way we do today. Women in the workplace was not a threat. But, this changes in the mid-19th century. The middle class develops and from this the idea that the definition includes the woman keeping to her sphere of the home. The woman having to work meant that the husband could not support his family.\n\nA major shift in men's attire begins to take place around the same time. We can look at the [1830s mens fashion](_URL_2_) and see an extremely feminine silhouette. Though, the colors are more subdued and \"masculine\" by todays standards and the trimmings are absent. A shift towards this takes place around the turn of the century. The fashion for English sporting attire takes full hold and items like boots become everyday wear rather than just for riding and sporting attire (previously they were not made to be walked in). I do have to note here that this shift was not due to Beau Brummel as history books love to attest. He might have been the epitome of a fashionable English gentleman, but saying he carried the reins on the fashion changes occurring is akin to saying Kim Kardashian made the rear-end popular (I refer you to Sir Mix-a-lot). While not covered in trimmings and gaudy colors, a great deal of time was spent by these gentlemen in dressing neatly and presenting an incredibly detailed and put-together appearance.\n\nWomen during the same time go through a very odd few decades. The 1780s fashions call for simpler styles with a great deal more masculine influence. The [redingote](_URL_6_), or great-coat, is incredibly popular and styled after a mans garment. This trend puts influence on jackets, pelisses, spencers, etc. over the next few decades. Women back away from this style influence in the late 1820s. Around the same time we see our men also trending towards a more feminine appearance.\n\nObviously, by the late 19th century men's attire has become the standardized business-like appearance we're accustomed to. I personally feel like there is a major tie-in to the gender separation of spheres during this time. Men are meant for the business/working world and should dress the part. Major changes in children attire come around this time as well. Up until the 1910s it was very common to dress children alike. Male vs. female didn't matter much until that little boy was out of diapers and fully potty trained. I even have images of my grandfather in a dress from the 1910s. A dress was just easier and it's not like the child cares. Surely, inventions of things like zippers, snaps, safety pins, and advancement in elastic make easily removable children's pants a possibility. But it still falls at rather a important shift in perception of gender.\n\nBy now men dress for work, women dress for fashion. In fashion, we find extremes that are not practical (like the horribly misguided anti-corset campaign from the turn-of-the-century claims, but that's another topic). The 1920s brings us boyish women. The reaction to this from the 1930s-50s is well studied as the pendulum swings to the opposite extreme for women's appearance. Post WWI and WWII there is a threat of women in the workplace, refusing to leave after being needed during the war. Combined with so many other changes, the 1950s becomes one giant Victorian revival to the extreme. It's shortly before this that blue for boys/pink for girls really takes off (thanks to advertisements to sell us more things). There is a nearly fanatical separation of masculine and feminine. I personally can't speak as well to the homosexual culture of this time outside of what we've all seen in media. There are definitely some more underground groups of cross-dressing, homosexuality, etc in the late 19th century. But the very public shaming of anyone even beginning to have comparative tendencies to these \"deviants\" seems to skyrocket in the 1950s.\n\nBut, men are still expected to appear incredibly clean-cut and business like. While this doesn't exactly happen instantly when jumping out of bed in the morning, it's not something to fuss over. At least not for the men. Wives fussing over their husbands appearance was more normal, even if it does bring about the nagging woman trope. \n\nPast this point I feel out of my element. It seems more closely tied to the stereotypes of homosexuals and their appearance than what is considered main stream fashion. While the macaronis of the 18th century didn't have their fashion extreme directly connected with those stereotypes of being gay, the fashionable extreme of the late 20th century certainly did. The same goes for the plainer, even more masculine women. The shift really occurs in the later half of the 19th century, but almost back-pedals with trouser-wearing, bike-riding feminists (or even flappers) and the indulgence of the 1920s that even reached men's attire. The post-WWII cultural reaction puts a quick end to that trend."
]
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"http://www.reddit.com/r/AskHistorians/comments/1wbbgn/why_has_mens_formal_wear_remained_largely_the/cf0okrl"
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"http://www.history.org/Almanack/life/homebeauty/images/spruce.jpg",
"http://3.bp.blogspot.com/-RDwzk5F2h-0/TxdGBK5yMtI/AAAAAAAABu0/kREP1cILmQs/s1600/Is+this+my+Daugher+Ann.jpeg",
"https://www.pinterest.com/pin/442689838341396437/",
"http://www.britishmuseum.org/research/collection_online/collection_object_details.aspx?assetId=384046001&objectId=1639577&partId=1",
"http://www.britishmuseum.org/research/collection_online/collection_object_details.aspx?objectId=1638818&partId=1",
"http://images.library.yale.edu/walpoleweb/oneitem.asp?imageId=lwlpr03852",
"https://www.pinterest.com/pin/241646336231383994/",
"http://images.library.yale.edu/walpoleweb/oneitem.asp?imageId=lwlpr04232",
"http://collections.museumoflondon.org.uk/Online/object.aspx?objectID=object-547443&start=362&rows=1",
"http://www.britishmuseum.org/research/collection_online/collection_object_details.aspx?objectId=3354814&partId=1"
]
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|
3xiky5
|
why do people leave useless answers to amazon product questions?
|
[This for example](_URL_0_) And I've seen a lot more. Why even bother answering if your answer doesn't provide useful information for the one asking?
|
explainlikeimfive
|
https://www.reddit.com/r/explainlikeimfive/comments/3xiky5/eli5why_do_people_leave_useless_answers_to_amazon/
|
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"Because Amazon asks people who have bought products to answer questions so some people just try to answer",
"You actually get an email from amazon, asking you if you can answer the questions (usually a product you recently bought).\nMy best guess would be that they think they are directly asked by that person. Doesn't make much sense, but so doesn't answering the question with a bad answer.",
"What's even more infuriating to me are people who give bad reviews for products without bothering to explain how it displeased them. *\"I did not like this product. It did not meet my expectations. Duh end.\"* It's as if some people literally do not understand the purpose of language and human communication."
]
}
|
[] |
[
"http://www.amazon.co.uk/forum/-/Tx8JIXZ7WCM2EN/ref=ask_dp_dpmw_al_hza?asin=B0000AN4D0"
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[],
[],
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|
5gxrm2
|
Does the supermassive black hole in the center of our galaxy have any effects on the way our planet, star, or solar system behave?
|
If it's gravity is strong enough to hold together a galaxy, does it have some effect on individual planets/stars within the galaxy? How would these effects differ based on the distance from the black hole?
|
askscience
|
https://www.reddit.com/r/askscience/comments/5gxrm2/does_the_supermassive_black_hole_in_the_center_of/
|
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"There aren't any noticeable tidal forces for most of the galaxy if that's what you mean. The ratio of the distance from the core compared with the size of celestial bodies is such that the gravitational effect of the core is essentially uniform for and given body (star, planet, etc.) That said, stars orbiting *very* close to the core are warped due to tidal forces.\n\nMost of the galaxy just orbits around the black hole. They're no more affected by its gravity (aside from their orbit) than you are by the Sun's. Which isn't to say none; it's just that local gravitational systems are far more influential. The inverse square law is a harsh mistress.",
"The premise that the black hole is holding together the galaxy is wrong. \n\nSagittarius A*, the supermassive black hole thought to be at the center of the Milky Way, is estimated to be the mass of about 4 million suns. \n\nTo put that in context, the milky way is estimated to have between 100-400 billion stars with a mass of about 12 trillion suns. This makes Sagittarius A* less than .0001% the mass of our galaxy. So no, it does not affect us. \n\nHaving said that, there are a few stars that orbit Sagittarius, and quite fast. [link](_URL_2_)\n\n---\nWhat does affect us, though? \n[here's an interesting thing to look at](_URL_1_)\n\nThe image on the left shows how the galaxy should be moving, predicted by the mass distributions and densities we observe from all sources of light. The image on the right shows how it is actually observed to be moving. \n\nThis is exactly why dark matter is hypothesized to exist. The image on the right is only possible if there exists an enormous amount of mass greater than that of the galaxy and outside of it. Just a quick search shows an artists rendition of it, but the scale is roughly accurate: [dark matter halos!](_URL_0_)\n",
"In the newtonian approximation any spherically symmetric distribution of mass can be represented as a point mass in the centre without changing the gravitational field outside the original sphere. This is why you can calculate the gravitational acceleration on the surface of the Earth (or any other planet), just by knowing its mass and radius.\n\nThis works in the other direction as well. The gravitational field of a million sun mass black hole and the same mass globular cluster are identical, outside the cluster.\n\nSo from our point of view the supermassive black hole is just extra mass. It could just as well be in stars, interstellar gas or dark matter. If it was in the same distance and direction just more spread out, it would have the same effect. Since it represents only a tiny fraction of the mass of the galaxy that effect is quite small.",
"Here's what I don't understand. If there's all this mass in the center of the galaxy pulling material towards it what is to prevent all mass from eventually falling into itself and creating one massive ball? Is it simply that this material was already moving at such a speed that it orbits the object rather than falling into the gravitational pull?",
"If heat from electric circuits caused the Pioneer 1 & 2 to slow down a measurable amount due to Newtons third law, then I'd say it at least has a small impact on us. I'm sure it can be approximated by F = Gm1m2/r2. ",
"Here's a question then:\n\nIf dark matter has gravity, and gravity is responsible for the formation of celestial bodies as things are attracted to one another, why is dark matter theorized as a halo? Wouldn't it cling to, or form its own bodies, even if it's invisible?",
"something to consider. black holes are not gravity monsters or anything. mass is still mass.\n\nfor example. if you converted our sun into a black hole it would still have precisely the same mass it has now.\n\nall the planets including earth would continue to orbit around the black hole as if it were the sun. no change at all (except that everything would be really cold since black holes don't make heat like stars do)\n\nbut gravitationally speaking you could not tell the difference between the sun and a black hole in place of the sun.",
"As long as you are \"free falling\" towards a gravity well, there are no measurable forces except the tidal force. But since the earth is very small compared to the galaxy itself, these tidal forces are infinitesimal small. \n\nSince there are no effects in a free fall (did i say that already?) the distance to the black hole doesn't matter. We could be \"very close\" and would still \"feel\" nothing.\n\nif you get very close, the tidal forces will tear you apart though. But that is an effect based on three forces: gravity + weak force + strong force.\n\n",
"We rotate wound the center of our galaxy in a toroidal sphere. Meaning we never actually rotate in a circle it's more like a spiraling doughnut. The spiral arm we are on changes throughout millions/ billions of years."
]
}
|
[] |
[] |
[
[],
[
"http://www.physast.uga.edu/~rls/1020/ch22/22-01.jpg",
"https://upload.wikimedia.org/wikipedia/commons/3/33/Galaxy_rotation_under_the_influence_of_dark_matter.ogv",
"https://www.youtube.com/watch?v=k7xl_zjz0o8"
],
[],
[],
[],
[],
[],
[],
[]
] |
|
21goht
|
Why did German soldiers pay homage to Joan of Arc during WWII?
|
This is a story that's circulated in my family since I can remember. I'm a dual citizen of France and the US that was raised in America (my father is a native French citizen). My grandmother was raised in a rural, eastern-central French town called Rigny-le-Ferron. So during the German occupation, our family owned one of the nicer homes in the city, and, as a result, had to house the officers of the German unit that occupied the town. In the courtyard of this home was a statue of Joan of Arc clutching a "French" (period) flag. So the story goes that any time the German soldiers stationed in the town came to speak with the officers staying at the house, they would stop to salute the statue of Joan of Arc. My question is: Is there a historical basis for these soldiers' actions? Or is this some random inexplicable act, as my family has always assumed?
|
AskHistorians
|
http://www.reddit.com/r/AskHistorians/comments/21goht/why_did_german_soldiers_pay_homage_to_joan_of_arc/
|
{
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"cgcvwmf"
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"text": [
"This is somewhat of a complex answer and she stretched far beyond German homage.\n\n1. It wasn't as much an homage to Joan of Arc the person, but more so what she began to symbolize in the late 19th century. Following the Franco-Prussian War, Joan of Arc began to represent a hopeful pride in a weakened nation. From Robert Frank's \"Collaboration and Resistance, Images of Life in Vichy France 1940-1944\n\n[…] there were different versions of Joan; two or three images, sometimes complementary, sometimes concurrent, prevailed: the Saint and the patriot always, the daughter of the people sometimes. The leftist republican and radical preferred the second and the third; the rightist favored the first while honoring the second.(1)\n\n#2 Édouard Adolphe Drumont\n\nDrumont was the founder of the Antisemitic League of France. Throughout Drumont's writings, would use Arc as a symbolic hero for his cause.Joan of Arc was described as a baptized Aryan by Drumont, an “aryenne baptisée” in La Libre Parole, May 30, 1894. (2) As she had already become a symbolic figure in many European societies,her believed Aryan qualities allowed her to be a cookie cutter icon. \n\nThe figure of Joan was exploited by anti-Semites in Algeria , with Drumont drumming up the troops. The anti-Semitic rioting that broke out in Algiers and Oran during the Dreyfuss Affair was carefully prepared: influenced by Drumont’s book La France Juive, which saw a ray of hope in Algeria’s anti-Semitism\n\nIt is important to keep in mind that since the Dreyfuss affair led to a spark in this anti-semitic movement, it also reignited upon his death in 1935. With his death, Drumont's attack on Dreyfuss was reignited although he had been writing about Joan of Arc for years. \n\n If the roots of the nazi genocide of Jews can be found in the anti-Semitism surrounding the Dreyfus Affair, as Drumont’s newspaper Libre Parole so deftly states on the front page of the Sunday, May 15, 1938 issue (“De fait, Hitler est venu bien après Drumont… [et] l’Antisémitisme ne sauraît donc être un terme synonyme d’hitlérien”), one might also suppose that the roots of Vichy’s Joan could be found with Edouard Drumont, Charles Maurras, and even Hilaire Belloc in translation, as well as in some of the Joan propaganda used during World War I. Posters attest to that fact: there is one with Joan in chains standing over churches in flames (representing Rouen), with the slogan: “Les assassins reviennent toujours… sur les lieux de leur crime”56. But a better conclusion might be the idea that Propagandists always come back to the strong symbol, and Joan of Arc is one of the strongest symbols available to the French people and the rest of humanity. (3)\n\n\n* 1 Robert Frank, Collaboration and Resistance, Images of Life in Vichy France 1940-1944, tr. Lory Frankel, NY: Harry N. Abrams, 2000, 213.\n\n* 2 Drumont’s article was entitled “Les dernières fêtes de Jeanne d’Arc” (La Libre Parole, May 30, 1894), quoted by Neil McWillliam, “Conflicting Manifestations: Parisian Commemoration of Joan of Arc and Etienne Dolet in the Early Third Republic”, French Historical Studies 27.2, Spring 2004,\n\n* 3 Reproduced in Laurent Bonnet and Louis-Marie Blanchard, En chemin avec Jeanne d’Arc, Rennes: Ouest France, 2004, 121."
]
}
|
[] |
[] |
[
[]
] |
|
31lf9e
|
why is it that we typically make eggs, bacon, pancakes, etc. for breakfast & why does it seem so wrong in a sense if we eat anything other than those typical breakfast foods for breakfast?
|
explainlikeimfive
|
http://www.reddit.com/r/explainlikeimfive/comments/31lf9e/eli5_why_is_it_that_we_typically_make_eggs_bacon/
|
{
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"text": [
"Conditioning. If you were raised on pizza and soda for breakfast, milk and cocoa puffs would seem weird.",
"Because that's what we're accustomed to. Other cultures eat very different things for breakfast. \n\nFor much of American history, breakfast was a hearty meal and included meat. This was heavily influenced by the English breakfast (as opposed to the continental breakfast), which features lots of fried things and meats. It wasn't until the Kellogg brothers and company started pushing a healthy diet and \"clean eating\" as a cure for every manner of bodily sms societal ills (including masturbation) that lighter breakfasts of cereals became the norm.",
"Pancakes for breakfast sounds wierd. That's a dessert, surely?",
"This was covered in a [Cracked article](_URL_0_) in 2012. Definitely worth the read.\n\n > Here's something you've probably never wondered: Why are some foods considered \"breakfast\" foods (pancakes, bacon, eggs) and others not? Why is it weird to eat pancakes for dinner and pizza for breakfast? Well, if what we know about bacon is any indication, it's purely a matter of marketing.\n\n > You only have to go back several decades to find a time when bacon for breakfast was about as alien as having a steak for dessert. The entire reason we even consider bacon part of a traditional breakfast is due to the work of one man and a lagging company's desperate attempts to sell their product.",
"I'm sorry I'm not answering the question, but I've never actually seen people eat pancakes for breakfast outside of TV and movies. It seems like it's way too much of a pain in the ass to cook when everyone's tired as hell and just trying to get out of the house. "
]
}
|
[] |
[] |
[
[],
[],
[],
[
"http://www.cracked.com/article_19833_the-7-sneakiest-ways-corporations-manipulated-human-behavior.html"
],
[]
] |
||
juvea
|
Why are sumo wrestlers able to maintain their athleticism while morbidly obese, but others of the same weight become bedridden and are at risk of sudden death?
|
I'm interested in things like the maximum pressure on human joints, compression of internal organs due to excess fat, high blood pressure and others I haven't thought of along those lines. TIA.
|
askscience
|
http://www.reddit.com/r/askscience/comments/juvea/why_are_sumo_wrestlers_able_to_maintain_their/
|
{
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"text": [
"sumos aren't morbidly obese. Turns out the bodyfat percentage on a lot of them is in the 15-30% range. Pair that wil the fact that they physically train, and you have, essentially, a power lifter body on a wrestler",
"sumos aren't morbidly obese. Turns out the bodyfat percentage on a lot of them is in the 15-30% range. Pair that wil the fact that they physically train, and you have, essentially, a power lifter body on a wrestler"
]
}
|
[] |
[] |
[
[],
[]
] |
|
w2c5s
|
Meat and colon cancer
|
I've gotten into a link-fight about evidence suggesting high meat consumption increases risk of colo-rectal cancer.
It started when I told my non-vego friends about this article:
_URL_0_
One of them shot back with Dr Briffa poo-pooing the idea of a connection:
_URL_1_
I see some holes in Briffa's points, like; a) diverting to argue about saturated fats instead of meat in general; b) citing decade-old studies; c) dismissing studies that are "epidemiological in nature" as "not proving anything".
However I'm open-minded and would like some knowledgeable input as to whether there are indeed links between meat consumption and higher incidence of colo-rectal cancer, or cancer in general - or if it's still too controversial to say at this point, as this Dr Briffa guy seems to suggest?
|
askscience
|
http://www.reddit.com/r/askscience/comments/w2c5s/meat_and_colon_cancer/
|
{
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"c59od26"
],
"score": [
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"text": [
"The best you can do is take a recommendation from a reputable source like the American Cancer Society. They have looked at all of the data as a whole and use that to make an informed recommendation. Most importantly, THEY HAVE NOTHING AT STAKE. They want to decrease cancer. You will find many studies (like the one in Dr. Briffa's blog post) that find red meat to be healthy are funded by meat producers. One study is not enough, one study can be wrong or botched, but many studies are much less likely to be so.\n\n_URL_0_\n\n*Risk factors linked to things you do*\n\n*Some lifestyle-related factors have been linked to colorectal cancer. In fact, the links between diet, weight, and exercise and colorectal cancer risk are some of the strongest for any type of cancer.*\n\n*Certain types of diets*\n\n*A diet that is high in red meats (beef, lamb, or liver) and processed meats (like hot dogs, bologna, and lunch meat) can increase your colorectal cancer risk. Cooking meats at very high heat (frying, broiling, or grilling) can create chemicals that might increase cancer risk. Diets high in vegetables, fruits, and whole grains have been linked with a lower risk of colorectal cancer, but fiber supplements do not seem to help.*\n\nAnother good source-\n_URL_1_\n\n*These two studies are impressive, and they don’t stand alone. A meta-analysis of 29 studies of meat consumption and colon cancer concluded that a high consumption of red meat increases risk by 28%, and a high consumption of processed meat increases risk by 20%.*"
]
}
|
[] |
[
"http://www.abc.net.au/health/thepulse/stories/2012/07/03/3533219.htm",
"http://www.drbriffa.com/2009/03/18/does-eating-meat-really-increase-our-risk-of-colon-cancer/"
] |
[
[
"http://www.cancer.org/Cancer/ColonandRectumCancer/OverviewGuide/colorectal-cancer-overview-what-causes",
"http://www.health.harvard.edu/fhg/updates/Red-meat-and-colon-cancer.shtml"
]
] |
|
4zbwwx
|
I'm a penniless, but free, peasant living in Italy at the beginning of the Renaissance. What can I do to start making money and rise into the bourgeoise class?
|
AskHistorians
|
https://www.reddit.com/r/AskHistorians/comments/4zbwwx/im_a_penniless_but_free_peasant_living_in_italy/
|
{
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"text": [
"In Florence you would find things... difficult, to say the least, but perhaps easier the younger and more talented in whatever craft you knew. At the time of the Renaissance, all meaningful means of production in Florence was tightly controlled by their respective guild, called *Arti*. The largest and most powerful was the cloth weaver's guild, the oldest, the dyer's guild, and included trades of nearly everything that you could think of. You were not free from the tight control of the guild, either, if your trade did not directly fall underneath one of seven to twenty-eight different guilds in Florence at the time for many trades were lumped in with their needed means of production as well. For example, painters fell under the *Arte dei Medici e Speziali*, the Physicans and Apothecaries' guild, because they had to go to pharmacies to purchase their dyes and pigments. \n\nThe different guilds worked as a unit to accomplish quite impressive goals. Establishing quality control, work hours, social safety nets for the families of guild members, along with instruction in their trade and craft for young boys taken in as apprentices and protection from foreign competition. \n\nHowever, while that is fantastic for anyone in the guild, you are a penniless dirtmonger supposedly with no significant connections to anyone important anywhere, or you would have used them to get your children or yourself ahead in life. You can't just set up your own stall, either, since the guild might literally come and destroy your work, and have the legal impetus to do so. You can't exactly sign up for the guild, either. To join the guild you had to have three things: to have paid an entrance tax, to have some amount of competence in the craft, and to be a legitimate son of a member. Since you are penniless, it can be safely assumed that you are not in fact, a non-bastard son of member of a guild and you can't pay the entrance tax anyways.\n\nHowever, you remember what I said about it being easier the young and more talented you were? The other way to join a guild was to be taken in by a Master of the Guild as a *garzoni*, an apprentice as a boy. Apprentices were promising young men who Masters thought might further the Guild's reputation with their skills, and were taken in to be instructed in the craft and to assist the masters in their work. Something like an internship that lasted many, many years. \n\nThe masters, or *capomasetri* each ran a *bottege*, a workshop which if you were young and talented enough, you might be taken in. It would be quite a long shot, however. With no one to vouch for you, no one to sponsor you and no one to please and favor by taking you in, a master would be taking quite the risk in taking on an utterly unknown peasant from nowhere. Your work would have to be quite exceptional, assuming upon being presented with your piece of work, they didn't just spit in your face and demand to know who's work you stole.\n\nThat said, if you could rise up through the ranks and marry the right people, you might just reach the rank of Master of the Guild, of which there were only a few in each *Arti*. And then, finally, you would well and surely reach the \"bourgeoise\" class. \n\nThis is not optional, by the way. You can't just be be only an artistic genius at this time period. My memory might be bad and I don't have m books with me, but I can't think off of the top of my head a single artist from the Renaissance that didn't find their \"humble\" beginnings under someone's tutelage in a workshop, in which case they already had a massive advantage over most of Florence's population. In Florence, everything was tied to the guild, unless you're taking about post-Medici ascendancy, in which case everything was tied to Cosimo's deep, deep pockets.\n"
]
}
|
[] |
[] |
[
[]
] |
||
49fmsy
|
why do some runners/drivers get a head start in pro races?
|
explainlikeimfive
|
https://www.reddit.com/r/explainlikeimfive/comments/49fmsy/eli5_why_do_some_runnersdrivers_get_a_head_start/
|
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"text": [
"If you're talking about racing around an oval track, the competitor on the outside has to cover a longer distance than the competitor on the very inside, which is unfair if they all started at the same time.",
"Because the runner/driver on the outside track runs a longer distance (a curve is longer when the radius is longer), the outside runners get head starts to equalize the distance each one covers.",
"So there are two answers:-\n\n1. Runners on a track are staggered according to what lane they are in because of the corners. The runners on the inside lanes will be running a shorter lap than those in the outside lanes.\n\n2. In vehicle racing, cars are staggered simply for spacing.\nIn Formula 1 for example, the day before the main race is used for qualifying where the competitors aim to get a better starting position for the main race.",
"Follow up questions:\n\nIn a foot race on an oval track, the turn radius is different for the different lanes. Does this make any difference? Like is it easier to run fast with a larger radius turn?\n\nWhy not just have a straight track? Obviously not as stadium friendly for longer races, but shouldn't fairness take precedence?",
"There are different reasons for different types of racing, are there any in particular you are thinking of?\n\nWith slower/shorter racing it can be distance - on a running oval like a 400m track runners are restricted to their own lane, but the outside lane takes more distance to travel around the corner, so the runner starts from a position ahead of the person in the next lane (but runs the same distance).\n\nIn most sports though it is just the practicality of starting everyone - in f1 or NASCAR it is impossible to start everyone in a straight line, so they have qualifying rounds to put everyone into a fair order. You do well in qualifying, you get the advantage of starting closer to the front.\n\nIn really big races like the London marathon there are so many participants it takes a fairly long time to let them all pass the start, so rather than starting at the same time and some people getting stuck waiting, they use individual clocks so that everyone gets timed separately from the moment they cross the start line. The same system is also used in individual sports like orienteering where participants are needed to start separately so they can't follow each other and have to choose their own routes, so are started at set intervals."
]
}
|
[] |
[] |
[
[],
[],
[],
[],
[]
] |
||
7mr9hz
|
Were there copies of the information in the library of Alexandria in other places around the world?
|
First off, sorry if this sounds too "a-ha! gotcha!"
While the library of Alexandria was a hub that carried tons of information, do we have records that suggest that all or some of the information in the library had copies in other libraries/information hubs around the world? It's just astonishing to me that so much information was all in one spot, and then when it was destroyed all of that information was just lost without other records somewhere.
Sort of a followup question, just how much did the destruction of the library actually slow down cultural/technological innovation?
|
AskHistorians
|
https://www.reddit.com/r/AskHistorians/comments/7mr9hz/were_there_copies_of_the_information_in_the/
|
{
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"drw6a59"
],
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"text": [
"[This thread](_URL_0_) from /u/XenophonTheAthenian seems like it may answer your questions (or at least parts of them)."
]
}
|
[] |
[] |
[
[
"https://www.reddit.com/r/AskHistorians/comments/5t6op5/facts_about_the_library_of_alexandria/ddkr2h6/"
]
] |
|
5rinkh
|
cellular respiration, why is it so important in maintaining animal health, growth and reproduction?
|
Looking for a simpler understanding of a process I find rather complicated.
|
explainlikeimfive
|
https://www.reddit.com/r/explainlikeimfive/comments/5rinkh/eli5_cellular_respiration_why_is_it_so_important/
|
{
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"text": [
"Cellular respiration isn't like, important in maintaining health. Its like saying a heartbeat is important in maintaining health.\n\nCellular respiration for animals..i guess, is how every cell gets energy to carry out(most) chemical reactions.\n\nThe Adenosine TriPhosphate molecule (ATP) that you see people typing out in this thread saying its energy for your body is what is the great yield from cellular respiration. Though the body technically \"uses\" it and you can say its the way energy is made in your body thats not entirely true.\n\nCellular respiration (wether it be calvin or krebs cycle respiration, aka plant or animal), is a type of chain reaction to really get Adenosine Diphosphate another phosphate group to make that molecule you keep hearing (ATP). \n\nSo the reason why is basically this molecule is set up in a way that the 3 phosphates on this adenosine-ribose complex (as per the term adenosine Triphosphate), is the perfect shape to manipulate the rest of the chemicals in your body. This is the \"energy\" you hear people associate with ATP.\n\nIn almost every single reaction in your body, you have like thousands of intermediary proteins, compounds, hormones, whatever, that will be involved to make a cell do something. ATP is flooded everywhere to allow those things to change their shape and in doing so allows the process to happen. When the molecules change their shape energy is being transferred, this is why you hear people associate it with energy.\n\nNow your question however, you're trying to imagine like cellular respiration being important in the process of health, growth, reproduction,.. whatever.\n\nThe thing is, ATP (and therefore cellular respiration) is technically why these molecules are moving and changing in the first place. Its not like an important factor, like oil in an engine, cellular respiration is the process of an engine. Its the entirety.\n\nAny biological mechanism you can think of probably involves atp somewhere. Any mechanism. Ever. So it's hard to denote cellular respiration like that. Growth, health, reproduction, these are on whole entire magnitudes of biological mechanisms that are going on, but just focus on one cell doing a n y t h i n g. Theres cellular respration, because you need ATP to have that happen.\n\nATP virtually makes the chemistry happen in biology. Without this molecule to change the shape (and therefore transfer energy, and in biology changing shape is the basic chemistry of the situation anyways), you would need something else to change the shape of molecules to control the chemical reaction you are trying to get at, like making a protein, moving a vesicle inside a cell, a ribosome creating protein from RNA,. i could almost list every single biological complex known and you would need the energy catalyst ATP to do it somewhere somehow. ATP causes biochemistry to happen, and there's no other chemical that can work well for that on this earth with earths biology, otherwise it would be dominant everywhere, but now we are going into evolutionary principle.\n\nNot even mulling over glycolisis or other forms of ATP production as its hardly ever found as the main contributor to ATP in most living organisms, and in almost every case is just an inefficient form of the calvin and krebs cycle of cellular respiration."
]
}
|
[] |
[] |
[
[]
] |
|
1m5kl5
|
in what context would you decide between saying "muslim" or "islamic"?
|
Or are they interchangeable? Or is there a difference between the two words that I am not aware of?
|
explainlikeimfive
|
http://www.reddit.com/r/explainlikeimfive/comments/1m5kl5/eli5_in_what_context_would_you_decide_between/
|
{
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"text": [
"Muslim and Islamic are interchangeable when used as an adjective. For example \"Muslim architecture\" and \"Islamic architecture\" are both correct. However \"muslim\" is also a noun that refers to a follower of islam and is not interchangeable in that context. For example you would say \"John is a muslim\" but not \"John is an islamic\" as the latter makes no sense",
"Muslim is to Islam as Christian is to Christianity.\n\nWhere Christian can be a worshipper *or* a \"thing\" that is Christian (Christian temple, Christian holiday, etc), generally a Muslim is a worshipper whereas Islamic would describe the \"thing.\" They can be more or less interchangeable though."
]
}
|
[] |
[] |
[
[],
[]
] |
|
242gqm
|
In a zero gravity environment if I were to punch forward would I move with the punch?
|
askscience
|
http://www.reddit.com/r/askscience/comments/242gqm/in_a_zero_gravity_environment_if_i_were_to_punch/
|
{
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"text": [
"No, as your hand moves forward your body will go backwards, but after both are done moving you will be stationary relative to your initial position.",
"Also, to clarify: If you punch *something other than the empty space in front of you* and hit it, you will move backwards... and continue to do so **forever** until you bump into something else (\"behind\" where you were initially.)\n\n(Added due to ambiguous source statement.)"
]
}
|
[] |
[] |
[
[],
[]
] |
||
b4bv4f
|
Did the British Isles have their own variant of Vulgar Latin? What happened to it?
|
On the continent, Vulgar Latin evolved into the languages we know today as French, Spanish, and Italian. But what about the British Isles? After centuries of Roman rule, did they develop their own dialect of Latin that might have gone on to become its own Romance language?
|
AskHistorians
|
https://www.reddit.com/r/AskHistorians/comments/b4bv4f/did_the_british_isles_have_their_own_variant_of/
|
{
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],
"text": [
"It's a difficult question, because evidence is scarce one way or another : the consensus is that Vulgar Latin might have been an urban language, especially in the south-eastern regions and place of active Roman institutions (such as York), which shared everyday use with British speeches, in a probable diglossic relationship, meaning that Vulgar Latin was the high social language.\n\nStill, Britain was comparativrly to the other provinces of western Romania, significantly under-develloped and without a real effort of Roman settlement safe near Roman camps, and especially in the western and northern margins, Britton was probably still an everyday language, but with the preservation of a Briton's cultural life. There's even an expression used by Roman soldiers for natives, in the Vindolanda's Tables : \"Little Bretons\" (Brittunculi) hinting at a cultural and political rupture as late as the early IInd century, which is at best less apparent in the Germanic limes.\n\nBritish Vulgar Latin, as far as it can be told giving the limited evidence there is (few inscriptions, study of borrowed Latin words in Germanic and Brythonic speeches), seems to have followed a similar evolution than in Gaul or Spain with maybe some antiquated pronounciation, maybe out of hyper-correction, sometimes, while classical and institutional Latin survived on its own too.\n\nBasically, Roman Britain shared a same Vulgar Latin linguistic ensemble with other latinized Roman provinces without apparent radical difference : a Gallo-Roman was probably able to understand a Britto-Roman without too much troubles, maybe able to identify the origin of this person thanks to their accent.\n\nSituation is much more difficult to assert after the collapse of Roman Britain in the Vth (namely the disappearence of urban life and the ruin of provincial romanisation) that took place. Certainly usage of Latin didn't vanished overnight and even in the VIth century there's evidence of an institutional, memorial use. We don't have evidence on how and when Vulgar Latin survived in Britain, but it certainly did giving the loanwords in Anglo-Saxon, Gaelic and Brythonic speeches.\n\nTheories over a \"Britto-Romance\" speech, meaning there the evolution of British Vulgar latin severed from mainland evolution do exist, but lacks some definitive evidence. Eventually, it is possible that it went trough a specific evolution mirroring Gallo-Romance, but the jury is still out until some proof can be made.\n\nBy the time Vulgar Latin speeches in the mainland gave birth to specific Romance languages (roughly after a period of four centuries, after the IVth, which wasn't only set by linguistic but as well institutional matters), there's no evidence that you had remaining Latin speakers in England. It's not clear what happened, but the social and cultural basis for Vulgar Latin was damaged enough that it probably favoured either a return to Brythonnic once Romano-British peoples were left with the former less romanised regions of Britain, and in areas giving birth to early Anglo-Saxon kingdoms the promotion of Germanic speeches as the language of the petty-kings (maybe, altough it's debated, with a hint of cultural apartheid).\n\n & #x200B;\n\n & #x200B;"
]
}
|
[] |
[] |
[
[]
] |
|
2ngrzw
|
Why is there vapor that comes off really cold things?
|
askscience
|
http://www.reddit.com/r/askscience/comments/2ngrzw/why_is_there_vapor_that_comes_off_really_cold/
|
{
"a_id": [
"cme2t8e",
"cme3496"
],
"score": [
3,
2
],
"text": [
"It's the result of atmospheric water vapour condensing into droplets.",
"I imagine you are talking about what you may see if you pull out a tub of ice cream from the freezer on a warm day you see little wisps coming off of the fridge and the object. Well it's not necessarily coming off of the object itself. The object has a certain temperature which will tend to cool the air surrounding it a little. This area of effect may decrease the temperature of the air to its dew point, at which temperature you may get condensation to form."
]
}
|
[] |
[] |
[
[],
[]
] |
||
50cwzo
|
why do we fall asleep faster when the environment is being rocked/swung about (i.e. car, baby's bed, ship)?
|
explainlikeimfive
|
https://www.reddit.com/r/explainlikeimfive/comments/50cwzo/eli5_why_do_we_fall_asleep_faster_when_the/
|
{
"a_id": [
"d7302ub"
],
"score": [
8
],
"text": [
"Surprisingly, it looks like the science is still out on this.\n\nMy two cents would be that it is a hypnotic effect though. Continuous rocking is also a soothing / coping habit for people experiencing anxiety. I would presume it gives the brain a predictable pattern to work with - and that predictability calms the mind.\n\nYou might say \"calms it how? Just because something predictable is occurring, doesn't mean something unpredictable isn't going to come along.\" Which is of course true - but the brain has limited resources. With rocking motions, some of those resources are now taken up by predictable stimuli, and leave less resources to imagine unknown stressors."
]
}
|
[] |
[] |
[
[]
] |
||
4jko7x
|
what exactly does the little blue gel pad at the top and the rubber pad at the bottom of my razor do? is it just for style and we all assume it actually does something like add comfort or something but it actually does nothing?
|
explainlikeimfive
|
https://www.reddit.com/r/explainlikeimfive/comments/4jko7x/eli5_what_exactly_does_the_little_blue_gel_pad_at/
|
{
"a_id": [
"d37cqgt"
],
"score": [
5
],
"text": [
"They're lubricant. They both help the razor slide more smoothly across your skin but also leave moisture behind to prevent your skin from drying out.\n\nThe one at the bottom would help with function as you don't want hair to catch on the blades. The one on top would be more for comfort.\n\nIf you learn how to shave properly, they're both redundant. You should have adequate lubrication on your skin before the razor touches it and you should be using some kind of after-treatment for comfort."
]
}
|
[] |
[] |
[
[]
] |
||
1pc8es
|
why does the us use a state system?
|
What do the residents of the western region of Virginia have in common with the eastern region that would allow them to have some say in what they should share in laws, regulations, benefits, etc.,? What made them decide that this should be a permanent system for the country?
|
explainlikeimfive
|
http://www.reddit.com/r/explainlikeimfive/comments/1pc8es/eli5_why_does_the_us_use_a_state_system/
|
{
"a_id": [
"cd0w38p"
],
"score": [
7
],
"text": [
"Because originally the USA were thirteen pseudo-independent colonies under the British crown. Contrary to common belief, the \"united\" states of America never got on with each other historically. Not all thirteen even rose up against the British to begin with, so when they eventually did unify they kept a federal system whereby each state retains some autonomy, but are \"united\" in the sense that there is a central government which has a limited jurisdiction over all (now 50) states. As such, all the states have some say in the laws of all but remain independent enough for differences between them to persist.\n\n*edited 52 to 50 because apparently that's how many states there are now lol"
]
}
|
[] |
[] |
[
[]
] |
|
cc12ez
|
how bugs (not referring to tiny ones) somehow get through screened windows with no noticeable entrances.
|
explainlikeimfive
|
https://www.reddit.com/r/explainlikeimfive/comments/cc12ez/eli5_how_bugs_not_referring_to_tiny_ones_somehow/
|
{
"a_id": [
"etjow2v"
],
"score": [
5
],
"text": [
"Info: are you talking like stuck between the screen and a closed window? \n\nIf so, many screens, while sealed into the screen frame itself, are able to be open and closed. They can run on a little track in the side of the window frame and can actually leave a small gap at the top (between the screen frame and window frame). While many bugs, like cockroaches, look huge, some can slide into places as thin as the thickness of a quarter. So even a small gap that you don’t notice or can’t see can be an exploitable entrance for bug kind."
]
}
|
[] |
[] |
[
[]
] |
||
1k4n0q
|
What are the origins of the Roman *Triarii*, and why did they assume the role of "the 3rd Line of defense?"
|
I have a specific question regarding the *Triarii* of the Roman Army. I am currently doing an independent study and may have discovered some interesting parallels regarding social divisions among certain armies. I am a scholar of Hellenic Greece, but have very little knowledge regarding Rome, so any information by AskHistorians' Ancient Rome scholars is greatly appreciated!
Is it known when and where the *Triarii* were first implemented? Was it under the Etruscan kings, and any that we specifically know of? Did they always have a role as the "3rd Line of Defense" or were they at one time the main force of an army? If this was the case, what caused them to adopt the role as "the veterans." Or is this a common misconception regarding them all together?
Since I'm pursuing relevance to Classical Greece, I'd appreciate any dates you could provide (centuries will suffice, the specific year is not necessary). Also, any reading you could recommend would be great! Thanks!
|
AskHistorians
|
http://www.reddit.com/r/AskHistorians/comments/1k4n0q/what_are_the_origins_of_the_roman_triarii_and_why/
|
{
"a_id": [
"cblg0sr"
],
"score": [
10
],
"text": [
"Ok I'm going to take a stab at this. \n\nThe Roman Army under the Etruscan kings was modeled after the Greek Phalanx with rounded shields (*hoplon*) and long spears. In 387 BC the Battle of Allia occurs and Rome is sacked. After the Gauls are driven back the phalanx is changed to the more recognizable legion with standardized weapons and armor for the most part. Livy discusses the organization of the Roman Army in 340 BC. Livy states that a legion was 5000 strong. After the phalanx was done away with the army was broken into groups known as *maniples* which consisted of two centuries in one *maniple*. A century was made up of 60 men for *hastati* and *principes*, and 30 men for *triarii*. The first line was known as the *Hastati* and was comprised of 15 *maniples* of heavily armored younger recruits with each *maniple* accompanied by twenty light soldiers (*leves*) who carried spears and javelins. The second line was another fifteen *maniples* of *principes* who were older and more experienced soldiers. The third line consisted of three types of soldiers: 15 *maniples* of veterans (900 *triarii*), the *rorarii* and the *accensi*. *Triarii* translates to roughly \"men of the third rank\". It is likely that they were present in the Samnite Wars (343-341 BC, 324-304 BC, 298-290 BC).\n\nIn the 4th century BC men were sorted into classes according to wealth, the *triarii* being the richest after the mounted *equites*. *Triarii* were armed with spears (*hastae*) about 2 metres (6½ feet) long. They also carried swords, or *gladii*, about 84 centimetres (29 inches) long. They used *clipei*, large round Greek shields, and bronze helmets. Armor consisted of heavy plate mail or chain mail depending on wealth and personal preference. \n\nThe role of the *triarii* was to be a last line of either attack or defense in battle. If the *hastati* failed to break the enemy the more experienced *principes* would move in. If they failed then the *triarii*, the most experienced and best equipped, would move in to either finish the enemy of provide cover for the *hastati* and *principes* to retreat. This led to the saying \"rem ad Triarios redisse\", \"it has come to the triarii\"- meaning things were not going well. \n\nThis pretty much gives a brief glimpse into the the origins of the triarii until they were reorganized in the late 3rd century BC. If you have any questions or need something clarified (I'm pretty tired so this may have come out as one big incoherent mess) feel free to ask. If anyone sees something wrong please say so. Sources below.\n\nSources\nSouthern, Pat. The Roman Army: A Social and Institutional History. Santa Barbara, CA: ABC-CLIO, 2006 (This is a really good starting book to help understand the Roman military)\n\nMatyszak, Philip. Legionary: The Roman Soldier's (unofficial) Manual. London: Thames & Hudson, 2009. ( A little childish but a very easy and fun read with good facts.)\n\nMatyszak, Philip. The Enemies of Rome: From Hannibal to Attila the Hun. London: Thames & Hudson, 2004. \n\nLivy: The Early Histories of Rome"
]
}
|
[] |
[] |
[
[]
] |
|
3p2exn
|
How often were horse riding accidents when it was the primary form of transportation?
|
I think of horseback riding as pretty dangerous nowadays so yeah
|
AskHistorians
|
https://www.reddit.com/r/AskHistorians/comments/3p2exn/how_often_were_horse_riding_accidents_when_it_was/
|
{
"a_id": [
"cw2oeku"
],
"score": [
5
],
"text": [
"Did you have a specific time period or country in mind for your question? And are you interested in just horse-riding accidents or also accidents involving horse-drawn vehicles? I own an old history of the English courts in the 1860s that lists statistics for accidents involving both riders and passengers in horse-drawn vehicles as well as details of specific incidents. I'd be glad to post some footnoted info from that source if it fits your question. \n\nEdit: My apologies for not contributing what I could find in my books, I am moving house at the moment and most of them are still packed. I haven't been able to find the relevant one."
]
}
|
[] |
[] |
[
[]
] |
|
2quj23
|
why does the dish for my satellite tv have to face south to receive signal?
|
explainlikeimfive
|
http://www.reddit.com/r/explainlikeimfive/comments/2quj23/eli5_why_does_the_dish_for_my_satellite_tv_have/
|
{
"a_id": [
"cn9mqrz"
],
"score": [
5
],
"text": [
"Because, if you live in the northern hemisphere, that's where the satellite is.\n\nThey're in a geosynchronous orbit - which means they're above the equator and orbit the earth in 24-hours. So they stay in the same spot in the sky."
]
}
|
[] |
[] |
[
[]
] |
||
d7sjh9
|
why do some diseases tend to localize to specific areas while others remain more general? for example, hand, foot, and mouth disease, or genital herpes.
|
explainlikeimfive
|
https://www.reddit.com/r/explainlikeimfive/comments/d7sjh9/eli5_why_do_some_diseases_tend_to_localize_to/
|
{
"a_id": [
"f143u4x"
],
"score": [
6
],
"text": [
"I suppose you're talking about communicable diseases. It all depends. But for viruses for instance, they can never infect a cell unless they bind to a receptor and get internalized. Not all cells express a receptor for a given virus, for example that's why you don't get the flu in your leg it binds to receptors in your airways. HIV to B cells in the immune system. Bacteria on the other hand, it depends on how they evolved. Some bacteria evolved mechanisms of immune evasion in particular environments, like the intestine and salmonella. Bacteria like to hide from the immune system because it's pretty good at killing them, so they tend to stay in the interstitium or in cells where the infection took place. H pylori for example evolved to dig into the mucosa in the stomach and hide from the acid by secreting a neutralizing buffer in its vicinity. Prions are another form of pathogen, they infect other prion proteins that are otherwise healthy. These proteins are most commonly found in the brain, so that's where prion disease progresses. You get the idea, but there's a lot more to the story obviously"
]
}
|
[] |
[] |
[
[]
] |
||
ad0fgk
|
Potato Famine
|
Recently in my us history class we were talking about immigration to the us and it’s effects on the economy and so on and so forth. I came across information suggesting that the famine was bad but that the British had caused it (not the fungus but by forcing them to live off potatoes) and could have intervened. I heard they sent back ship full of donated grain from Massachusetts and their excuse was it would interfere with trade. To what extent did the British cause and continue to cause Irish suffering and were the people of Great Britain complicit in this?
|
AskHistorians
|
https://www.reddit.com/r/AskHistorians/comments/ad0fgk/potato_famine/
|
{
"a_id": [
"edcm9mj"
],
"score": [
2
],
"text": [
"Not to discourage further discussion, but you might be interested in this previous answer on the subject by u/mikedash:\n\n* [Was England's role in worsening the potato famine one of neglect or did they actually try to increase the suffering?](_URL_0_)"
]
}
|
[] |
[] |
[
[
"https://www.reddit.com/r/AskHistorians/comments/5jcffu/was_englands_role_in_worsening_the_potato_famine/dbf9wnn/"
]
] |
|
3vo6lh
|
Why does the ball in this gif go in the direction it does?
|
Here:
_URL_0_
I know the bernoulli's theorem, that where the speed is high the pressure is low and vice versa. So here when the guy spins the ball inwardly, the speed of air on the near side is higher and so the pressure should be lesser. This means that the ball must move backward,i.e. opposite to the direction it moved in.
|
askscience
|
https://www.reddit.com/r/askscience/comments/3vo6lh/why_does_the_ball_in_this_gif_go_in_the_direction/
|
{
"a_id": [
"cxp6zzl",
"cxp799q",
"cxpa5aa",
"cxpcux9"
],
"score": [
30,
54,
11,
2
],
"text": [
"Once falling, the air on the near side is actually being slowed down by the texture of the ball pushing back against the oncoming wind. This gets more pronounced as the ball falls faster. The far side air is being sped up by that side of the ball going in the same direction as the passing air. \n\nThis results in the higher pressure building up on the near side of the ball, lower pressure on the far side and the ball heading outwards as a result.",
"[Here's](_URL_0_) the video that gif came from. The Magnus Effect is what they're demonstrating. The video does a good job explaining what's happening, but here's a short version: the ball moves through air, but because it's spinning the interaction with the air is different depending whether the air is moving with the spin or against it. Those two different \"sides\" of the ball result in different forces on those different sides. The force on the side where air opposes the spin moves the ball in a direction (like you saw in the gif/video).",
"/u/Midtek gave an incredibly thorough answer to this question in a recent thread. [Anyone interested in getting knowledge bombed should check out this link.](_URL_0_)",
"Follow up question: Where does the energy for the ball's horizontal velocity come from? It doesn't seem like he spins the ball hard enough to account for it. So does the spin transform some of the gravitational energy into horizontal velocity? If so, would the ball accelerate less quickly and hit the ground later than a ball dropped without spin?\n\nedit for clarity: As far as I can tell, there are two sources of energy that could be used to push the ball sideways - the kinetic energy stored in the ball's rotation and the potential energy stored in the ball's height when dropped. So either the spin gets converted into sideways velocity or some of the downward acceleration gets converted into sideways velocity, right?"
]
}
|
[] |
[
"http://i.imgur.com/KuayNFt.gifv"
] |
[
[],
[
"https://www.youtube.com/watch?v=2OSrvzNW9FE"
],
[
"https://www.reddit.com/r/askscience/comments/3ucg1v/will_rotation_of_a_smooth_object_change_the/cxdqq72"
],
[]
] |
|
643k3q
|
Assuming identical atmospheric and other planetary conditions, is a hotter sun always brighter?
|
Imagine we make an identical copy of Earth. Is there any conceivable type of star that this copy could orbit, at any distance, where the result would be Earth-2 being *hotter* despite the fact that the light levels are *lower*? Or are heat and light always positively correlated, holding atmosphere constant?
|
askscience
|
https://www.reddit.com/r/askscience/comments/643k3q/assuming_identical_atmospheric_and_other/
|
{
"a_id": [
"dfzw7mt",
"dg1zf6o"
],
"score": [
3,
2
],
"text": [
"Luminosity is a product of the surface area and temperature, so if you have two stars with equal surface temperatures and different radii, the one with the larger radius will have a greater luminosity. Likewise, a star with a temperature 2,500 K cooler than the Sun could be hundreds of thousands of times more luminous with the right radius, as you'd expect from a red supergiant or hypergiant.\n\nFor stars that are still fusing hydrogen in their cores (main sequence stars), like the Sun, there is an intrinsic relationship between mass, temperature, luminosity, and lifetime. There'll be individual variations based on the star's exact age and composition, but as a general rule, increasing the mass causes a main sequence star's temperature and luminosity to increase, and its maximum age to decrease. When you [plot them by colour (which gives you the temperature) and luminosity/magnitude](_URL_0_), you'll notice that they fall along a strip with the lowest-mass stars at the cool/red end, which is where the \"main sequence\" term comes from.\n\nFor stars that have moved past core hydrogen burning (generally giants of some sort or other) though, the temperature and luminosity will depend more what's happening in its interior at any given point in time. Mass and chemical composition will still determine their general post-main sequence evolutionary path though.",
"Absolutely. An Earthlike planet in the habitable zone of a red dwarf, for instance, could get substantially less visible light than we do, but still be fairly warm, because a cooler star radiates proportionally more of its energy in infrared, rather than in visible light."
]
}
|
[] |
[] |
[
[
"https://upload.wikimedia.org/wikipedia/commons/1/17/Hertzsprung-Russel_StarData.png"
],
[]
] |
|
46nvpv
|
why do cars that are not driven rust while cars that are regularly driven do not?
|
Assuming that the one that doesn't drive just sits in the driveway and has for a few years, and the one that is driven regularly gets typical under the hood maintenance. They experience the same weather and same amount of sunlight. The undriven car isn't experiencing the wear of the driven car.
|
explainlikeimfive
|
https://www.reddit.com/r/explainlikeimfive/comments/46nvpv/eli5_why_do_cars_that_are_not_driven_rust_while/
|
{
"a_id": [
"d06n07w",
"d06o8tp",
"d06ouo4",
"d06wmzs"
],
"score": [
3,
10,
3,
2
],
"text": [
"the paint deteriorates, allowing water to get to the metal. also, as my cousin learned with his 79 camaro, when you leave it outside in the sun, it can eat away at the rubber stripping along the windows, allowing water to seep into the car and eat away things like the floor pan. also, depending on where you live, driven cars will get hit hard with rust due to salt on the roads, and in those areas the owners must be diligent to wash under the car, and possibly spray an undercoat on it",
"45 years working on cars and restoring them. I don't agree with your question, most cars that just sit do not rust worse than those that are driven, especially up north with all the salt on the roads. What data/experience are you deriving your question from?",
"Cars that sit face the same elements without getting washed. Leaves clog drains, water gets inside. Windows are never opened to air the car out. Another big problem is the snow or water under the car doesn't evaporate away quickly. If the car sits on grass it eventually sinks to the ground really deteriorates.",
"The biggest universal problem of letting a car (or any piece of machinery) sit will be that any rubber seals, o-rings, or gaskets will dehydrate and crack due to lack of movement and/or lubrication. Rust is likely a more regional environmental issue. "
]
}
|
[] |
[] |
[
[],
[],
[],
[]
] |
|
4d9dt0
|
Why did the Japanese never adapt with anti-submarine tactics in response to U.S. submarine warfare in World War 2 that devastated Japanese merchant fleets?
|
[deleted]
|
AskHistorians
|
https://www.reddit.com/r/AskHistorians/comments/4d9dt0/why_did_the_japanese_never_adapt_with/
|
{
"a_id": [
"d1p7oco"
],
"score": [
45
],
"text": [
"Part of the reason was an obsession on the part of the Japanese Naval General Staff on the idea of a decisive battle - in 1890, an American strategist called Alfred Thayer Mahan published an extremely influential book called *The Influence of Sea Power Upon History*. This espoused the idea a single, decisive naval battle could decide the outcome of the entire war, and was widely studied in Japan. \n\nMuch of the IJN's planning before and during the war was therefore based on the idea of bringing the American fleet to such a battle somewhere in the Western pacific, with the big gun battleships of the IJN hopefully being able to triumph. In this type of short decisive conflict there is much less need for anti-submarine warfare (ASW). \n\nThere was also a cultural reason why few resources were devoted to ASW. The code of *Bushido* - the Samurai warrior culture which permeated the Japanese military meant that few officers found any \"honor\" in the relatively unglamorous work of escorting merchant ships, and placed more importance in offensive action rather than defense. Instead, Japan's destroyer's trained extensively to fight surface actions in line with the Mahanian doctrine. \n\nSource: *The Conquering Tide: War in the Pacific Islands, 1942-1944*, Ian W Toll. (2015). "
]
}
|
[] |
[] |
[
[]
] |
|
23pmok
|
Why are particles in a superposition state 'forced' into a certain state due to observation/measurement?
|
I only have a very, very vague understanding of quantum mechanics so my question may be stupid. I've always just wondered how measurement or observation can have an effect on a particle without directly interfering. Even if we say that something is in a superposition or 2 states at the same time, I still don't get why or how measurement can determine its state.
|
askscience
|
http://www.reddit.com/r/askscience/comments/23pmok/why_are_particles_in_a_superposition_state_forced/
|
{
"a_id": [
"cgzends"
],
"score": [
6
],
"text": [
"This is an often asked question - and for good reason. While physicists agree on the basic ideas of measurement, they do not agree on the deeper (arguably philosophical) nature of it. \n\n > I've always just wondered how measurement or observation can have an effect on a particle without directly interfering. \n\nIt certainly cannot. What physicists refer to as measurement requires interaction. What happens during interaction between two particles is that they become a pair of entangled particles. Let's say you have a, A, particle that is in superposition of spinning A={UP **and** DOWN}. Now let's say we make it interact with another particle, B, and they become entangled as the state AB = {UP, UP **and** DOWN, DOWN}. So they're in a state of both spinning up **and** both spinning down.\n\nLet's say we ignored particle B and just looked at A. If we perform an experiment on A alone after it has become entangled with B we would discover that the state of A is now A = {UP **or** DOWN} . What's interesting is that this particle no longer behaves like it's in superposition. It's in one state or the other, not both. It looks like it has been measured! But if we performed an experiment with both A and B we would see that they're not measured. Entanglement is strange. I could show the math, but I doubt it'd help.\n\nDuring what we call a measurement A doesn't just become entangled with a single particle B, but entangled with the entire measurement apparatus and the surroundings through a process called decoherence. The measurement apparatus is not just one particle more than 10^24 particles. Like before, performing an experiment on just A will make A look like it has been measured. \n\nIf you wanted to perform the experiment that showed A was not measured, you would have to perform an extremely complicated experiment on the entire measurement apparatus. That is way, way beyond our abilities, so we say that for all practical reasons, the particle has been measured. And some people even go as far as saying that because we can't show that A is entangled with the measurement apparatus, there is no entanglement. \n"
]
}
|
[] |
[] |
[
[]
] |
|
4jeh8p
|
Is it theoretically possible to freeze photons?
|
Do elementary particles freeze at absolute zero? Can we [humans] ever go sub absolute zero?
|
askscience
|
https://www.reddit.com/r/askscience/comments/4jeh8p/is_it_theoretically_possible_to_freeze_photons/
|
{
"a_id": [
"d3606yn",
"d360zhl",
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"score": [
22,
10,
2
],
"text": [
"The particles in a system do not \"freeze\" at absolute zero. A system at absolute zero should be defined to be in its quantum mechanical ground state. Because of the Heisenberg uncertainty principle, this does not correspond to \"no motion,\" since setting all particles to having zero motion will result in infinitely fluctuating positions. Also, for example, no two electrons can occupy the same state (the Pauli exclusion principle), so in a system with many electrons you need some electrons to occupy very highly excited states. In an ideal metal at zero temperature, some electrons have an average momentum of ~10^6 meters/second, so this can be very different from \"no motion.\" \n\n > Can we [humans] ever go sub absolute zero?\n\nWe cannot, due to the [third law of thermodynamics](_URL_0_), which essentially says that it takes an infinite number of steps to go from any finite temperature to zero temperature. However, a lot of systems at low-enough temperatures behave similarly to their zero-temeprature ground state, so in many cases working at T=0 is actually a fine approximation. Many aspects of electrons in a metal at room temperature can be calculated by a T=0 approximation, since the relevant energy scale is very large (see the example above).\n\nActually, I should say that your example with photons is a little special, since describing a gas of photons at a given temperature requires you to account for the fact that photons can be created and destroyed with no extra cost in energy. So as you heat up the system, more photons are created, and as you cool it down, photons can be annihilated out of the vacuum. At zero temperature I think the system will just go to the \"photon vacuum\" where there are no photons. But keep in mind that describing your system as having a temperature T implicitly means that your system is exchanging energy with something external with a temperature T.",
"At absolute zero, everything is at its lowest energy state. If you have a particle in a box, it will still move since by the uncertainty principle there must be some uncertainty in the velocity for there to be any certainty in the position. But it is a steady state. If you look for the particle from one second to the next, the probability distribution of where you find it won't change.\n\nPhotons don't need to exist. The lowest energy state won't have them. So the idea of a photon at absolute zero is a contradiction in terms. If you pretended they did need to exist, and looked at the lowest energy state with a photon, then if it's bound it's like the particle in the box. It still has momentum, but it makes a standing wave in the box and the system doesn't change. If the photon is unbound, then it can be arbitrarily low energy and there is no lowest energy state containing the photon.\n\nYou cannot reach absolute zero.\n\nYou can *technically* go below absolute zero. Although it would be more accurately described as above infinity. The way temperature is defined, if a system has so much energy that there are fewer and fewer ways to add energy, and adding energy removes entropy, then the temperature is [negative](_URL_0_).",
"No sure about actually \"freezing\" light in the cold way but scientists have \"frozen\" (stopped) light in a crystal for a while minute.\n\n_URL_0_"
]
}
|
[] |
[] |
[
[
"https://en.wikipedia.org/wiki/Third_law_of_thermodynamics"
],
[
"https://en.wikipedia.org/wiki/Negative_temperature"
],
[
"http://www.extremetech.com/extreme/162289-light-stopped-completely-for-a-minute-inside-a-crystal-the-basis-of-quantum-memory"
]
] |
|
b0zjzm
|
how do animals, like squirrels & foxes, know what is food and what isn't, in urban environments, especially processed foods.
|
explainlikeimfive
|
https://www.reddit.com/r/explainlikeimfive/comments/b0zjzm/eli5_how_do_animals_like_squirrels_foxes_know/
|
{
"a_id": [
"eij12ix"
],
"score": [
2
],
"text": [
"First they learn from parents by what is being presented to eat and what they see being eaten.\n\nSecond they have some instincts to avoid or pursue certain smells or tastes.\n\nThey learn by trying, if they puke up something that still looks and smells like that thing they ate, then they avoid it later. Particularly if it causes pain. Same with messes coming out the other end.\n\nAnd finally, as others said, they often don't and end up eating something not food. Maybe \"harmless\" in that it is not nutritious but not dangerous, or might be something bad for them.\n\n & #x200B;\n\nSome animals suffer greatly around us and others (trash pandas) do just fine."
]
}
|
[] |
[] |
[
[]
] |
||
3vbevq
|
Does high pH water have a lower capacity as a solvent to dissolve more because of the electrolytes and minerals already in the water?
|
Just a random question. I have some water with a pH of 8.8 and had the thought of using to make things like powdered gatorade, coffee, tea, etc.
|
askscience
|
https://www.reddit.com/r/askscience/comments/3vbevq/does_high_ph_water_have_a_lower_capacity_as_a/
|
{
"a_id": [
"cxm3ex7"
],
"score": [
14
],
"text": [
"It depends on the ions that are already in the water. If the ions are also the same ions that are in the substance you are trying to dissolve, then the substance will dissolve less. If the ions can react with the ions in the substance you are trying to dissolve, then the substance will dissolve more. And if neither of these occur, then your water will behave just as pure neutral water in terms of dissolving your substance."
]
}
|
[] |
[] |
[
[]
] |
|
cj3rpj
|
how do some cars have a birds eye view of of the car when they’re parking?
|
explainlikeimfive
|
https://www.reddit.com/r/explainlikeimfive/comments/cj3rpj/eli5_how_do_some_cars_have_a_birds_eye_view_of_of/
|
{
"a_id": [
"evay0ha"
],
"score": [
16
],
"text": [
"The car has cameras in the front, rear, and in the two side mirrors. Those images are stitched together (kind of the same way that your phone creates a panorama) to give a kind of 360° view of the car's surroundings. That image is then displayed in such a way that it looks sort of like a bird's-eye view instead of like the 360° panorama that it actually is."
]
}
|
[] |
[] |
[
[]
] |
||
6tbv61
|
how did nicknames for names like richard and charles become dick and chuck and other ones like that when they are so different from their original form?
|
explainlikeimfive
|
https://www.reddit.com/r/explainlikeimfive/comments/6tbv61/eli5_how_did_nicknames_for_names_like_richard_and/
|
{
"a_id": [
"dljhyc4",
"dljjbiz",
"dljm8hx",
"dljustx"
],
"score": [
13,
8,
6,
13
],
"text": [
"Some of my friends told me that Dick comes from Richard due to the original nickname of Richard being \"Rick\". After that, Dick came to be due to its rhyming with Rick.",
"What about Billy from William?",
"Interesting! How do you get Molly from Mary, then?",
"All I wanna know is if Steve is short for Steven then why isn't Steph short for Stephen rather than Stephany? And what's short for Stevany????? Stev????? Help!!!!!!!!"
]
}
|
[] |
[] |
[
[],
[],
[],
[]
] |
||
d89je3
|
why is it that light can travel for a billion years across the universe, but as soon as you flick off a light switch it disappears instantly?
|
[deleted]
|
explainlikeimfive
|
https://www.reddit.com/r/explainlikeimfive/comments/d89je3/eli5_why_is_it_that_light_can_travel_for_a/
|
{
"a_id": [
"f18kjbq",
"f18lanh",
"f18ldih",
"f18lsyl",
"f18lv3w"
],
"score": [
11,
10,
3,
3,
45
],
"text": [
"Light travels very fast. A source is needed for the light. \n\nWhen you turn off the light, it's no longer emitting light. The light wave that was sent just before you take it off takes almost zero time to reach the point where the light is absorbed (whatever the light is shining on in the room).\n\nThe light that is traveling billions of years just hasn't reached the point where the light wave is absorbed.",
"Your question in the subject line is answered in the text box. \nIn the billions of years in space, it doesn't encounter anything. Because it is space, the absence of stuff to encounter. \n \nAs for the why hitting stuff makes that light \"disappear\". \nWhen the light hit stuff, it gets turned into heat and stops being light. \nThe light bulb makes the wall slightly hotter. \n \nGranted there isn't a whole lot of energy involved. \nMost light sources made by human are producing heat by accident, overwhelming the amount of heat made by light.",
"I'm not sure I can ELI5 particle physics, but the majority of photons are converted into a different kind of energy when they come into contact with another force.\n\nWhat we know as \"heat\" energy is really just \"kinetic\" energy. Everything is made of particles, and heat is (on a basic level) just vibrating particles.\n\nLight can travel across the universe because it is unlikely to hit anything. No matter what sci-fi tells us, if you picked a direction and headed that way in space you would be extremely unlikely to ever come into contact with anything.\n\nIn a room, the photons will be absorbed by... well by anything they touch. Any photons reflected from a wall will either be reflected or absorbed by what they hit next until every photon has been absorbed.\n\nAs light travels crazy fast (as in 7 times around the planet in a second fast) this will all occur in a moment, basically instantly to the eye.\n\nHowever, if you could get a super duper mega slow motion camera, you would see the room slowly fade to darkness as the photons were absorbed, imparting teeny tiny little parts of warmth to whatever they touch.",
"Because not all of the light is reflected. Some of it is absorbed (and re-radiated as heat). Your blue wall, absorbs red, yellows, and greens (not completely, but enough). But even this blue light is not completely reflected. Some of it is absorbed too.\n\nEvery time the light bounces some of those photons are absorbed. And because light is really really fast, even if it takes 100 or 1,000 or 10,000 bounces across your 10m room to absorb so much you cant see it, it's still basically instantaneous. \nLight travels at 300,000km/s. The 100km (10m x 10,000 bounces) travel of light happens in 1/3,000 of a second.",
"The second part is your real question, you are wondering why the light disappears instead of bouncing around in the room. The answer is that it does bounce around in the room, it is just that it bounces around so fast that it is absorbed effectively instantaneously. Material absorbs light, the less light it absorbs the more reflective it is. But even the most perfect mirror absorbs some of the light that hits it. Light just travels so damn fast that even really reflective materials absorb it 'instantaneously', although if you could measure how many times it bounces back and forth you'd find it takes ever so slightly longer to go dark in a room made of mirrors than your normal off-white semigloss."
]
}
|
[] |
[] |
[
[],
[],
[],
[],
[]
] |
|
8lxvqt
|
How does lava stay hot until it hits the surface?
|
It seems like a cools pretty rapidly once it hits the surface- why doesn't do this when it's 8 feet below ground? Or even a hundred feet below ground?
|
askscience
|
https://www.reddit.com/r/askscience/comments/8lxvqt/how_does_lava_stay_hot_until_it_hits_the_surface/
|
{
"a_id": [
"dzjbcfy"
],
"score": [
17
],
"text": [
"It's only the bits touching the air that seem to cool very rapidly at the surface. The more inner parts can take months to cool, as they become insulated by the solidified outer layers. Even in this case the convective cooling of the air is helping speed up the cooling of the lava.\n\nDeep below the ground, there are no convection currents in the surrounding crust to speed up the cooling of the magma. But that doesn't mean it does not cool down at all. There are a great many igneous rock formations that appear to have formed from the solidification of subsurface magma chambers. It just takes a very long time."
]
}
|
[] |
[] |
[
[]
] |
|
3e1my0
|
Why would the high pressure of Jupiter's atmosphere destroy a probe?
|
I've heard from at least a few sources that any attempt to investigate Jupiter's atmosphere with a probe would result in the probe being crushed.
But if a probe can be designed with no gas or vacuum chambers, which I assume it can, why would pressure stop it from functioning?
|
askscience
|
http://www.reddit.com/r/askscience/comments/3e1my0/why_would_the_high_pressure_of_jupiters/
|
{
"a_id": [
"ctapgp9"
],
"score": [
4
],
"text": [
"We actually send a probe to sample Jupiter's atmosphere called Galileo, it fell into a region without many clouds though and Nasa didn't get much useful data back if (I recall). \nVirtually any probe would eventually get crushed and melt as it fell deep into Jupiter's atmosphere because it gets really really hot and very very dense, not something our technology could survive for very long. \n\nIf we could send back the data in time we could definitely investigate Jupiter's atmosphere. "
]
}
|
[] |
[] |
[
[]
] |
|
45n2fo
|
what happens next since justice scalia passed away?
|
explainlikeimfive
|
https://www.reddit.com/r/explainlikeimfive/comments/45n2fo/eli5what_happens_next_since_justice_scalia_passed/
|
{
"a_id": [
"czywacs"
],
"score": [
5
],
"text": [
"Obama is going to appoint a new justice and that Justice will need to be confirmed by Congress. This is a pretty huge deal since the old court was pretty evenly split on issues because about half the court was liberal and half was conservative with John Roberts being the swing vote. Now the majority is going to be liberal. "
]
}
|
[] |
[] |
[
[]
] |
||
2msj4y
|
what does obamas executive order on immigration do exactly?
|
explainlikeimfive
|
http://www.reddit.com/r/explainlikeimfive/comments/2msj4y/eli5_what_does_obamas_executive_order_on/
|
{
"a_id": [
"cm76g26",
"cm76mmy"
],
"score": [
3,
3
],
"text": [
"From what I heard on Fox News, it shreds the constitution.",
"I can't answer fully, but it sounds like there are a few broad scenarios in which Obama says that we will not deport, and we will give a Social Security number. Allowing people to effectively be here legally and able to work (indefinitely?)\n\nIt sounds like if you were < = 16 by 2010, you get to stay. If you have a kid that gets to stay, you also get to stay. If you have a legal citizen kid born here, you get to stay. \n\nAs for the complications that come, I don't know. Does this qualify all of them for social welfare programs, and lead to being able to vote is local elections? I don't know. "
]
}
|
[] |
[] |
[
[],
[]
] |
||
ivspc
|
Is good posture an indicator of good health?
|
Read a newspaper blog and it noted something on posture and its correlation to health/fitness. I'll post the link when I get back as I am on my phone now.
In my opinion, I think there is a correlation but its based on logic: if a person were to go to the gym, do weights (in proper) form, the posture should be quite decent. And if the same person hits the gym, frequently enough, he/she should be healthy. Naturally, this is all speculation. Is there a scientific proof?
EDIT: Apologies. I think I misread the quotation from the [article](_URL_0_). But it was the quoted line that made me think of the question in hand. Hope my mis-quotation doesn't deviate from the topic.
> You must balance your body with an equal ratio of back exercises to ensure balance and decent alignment. Good posture means a good body. Hunched over posture means you look like the antagonist in a Marvel Comics movie.
|
askscience
|
http://www.reddit.com/r/askscience/comments/ivspc/is_good_posture_an_indicator_of_good_health/
|
{
"a_id": [
"c27143c"
],
"score": [
3
],
"text": [
"Another anecdote: I teach a few yoga classes a week, and I run. Yoga focuses closely on alignment in legs and feet, as well as the spine. When running at the park, I notice that almost all the good runners have their feet pointed straight forward and use good form. The people huffing and puffing slowly down the trail often have supinated or pronated feet. I don't think running is necessarily great for correcting lower leg alignment; I think people with poor alignment get shin splints and stop running. In almost any sport, people with good posture will get injured less, and injuries can be as small and common as a sore muscle that causes you to miss a workout."
]
}
|
[] |
[
"http://www.smh.com.au/executive-style/fitness/blogs/boot-camp/dont-waste-your-time-at-the-gym-20110708-1h6co.html"
] |
[
[]
] |
|
vowsc
|
How would saturn-like rings affect life on an earth-like planet?
|
askscience
|
http://www.reddit.com/r/askscience/comments/vowsc/how_would_saturnlike_rings_affect_life_on_an/
|
{
"a_id": [
"c56capa"
],
"score": [
2
],
"text": [
"Saturn's rings are actually not very dense. They don't really have an impact on Saturn's surface, so you could probably easily assume the same if they were around an Earth-like planet. Here are my thoughts:\n\n > how would they appear in the sky?\n\nMost likely, they would be planar around the equator. So, someone standing on the equator would just see a \"line\" that is the edge on ring passing directly overhead going from east to west. However, the Sun would not follow that line perfectly because we have seasons. Sometimes the Sun would be north of that line, and sometimes south.\n\n > Would they have a bluish tint reflected from the oceans?\n\nNo. From the surface, they will be dim (like how the moon is dim during the day), but still visible. They will have a bluish tint during the day due to the scattering of the atmosphere. At night, they could really be any color, it really is determined by the composition. Most likely they'd be a light grey or white.\n\n > Would they cast shadows on the surface, and would these shadows be regular or irregular in passing over given spots?\n\nThis is a really interesting question. Like I said, the rings are super dense, so light can still pass through. There would be a small shadow, but it wouldn't be pitch black. More like twilight I would think.\n\nThe shadows would be very irregular, depending on the time of day and season.\n\nOther thought:\n\nSaturn's rings have gaps in them caused by the gravitational effects of their moons. Some moons are actually within the rings, and some moons are beyond them but pulling gaps in the rings..."
]
}
|
[] |
[] |
[
[]
] |
||
2i894q
|
What determines the frequency of a photon?
|
Please don't say "the energy." This doesn't explain it. I'm asking for the root of what determines the energy of a photon I suppose.
|
askscience
|
http://www.reddit.com/r/askscience/comments/2i894q/what_determines_the_frequency_of_a_photon/
|
{
"a_id": [
"cl04jyw",
"cl0es58"
],
"score": [
3,
3
],
"text": [
"Conservation of energy in the process that created the photon?\n\nI don't think I understand the question.",
"A photon has to be created in a physical process within the system S. This process has to obey conservation of energy. Thus the difference in energy of the system S before the process and the energy of S after the process is equal to the energy the photon carries. "
]
}
|
[] |
[] |
[
[],
[]
] |
|
7ds6s3
|
why do lighters have smaller flames when cold and bigger flames when warm?
|
explainlikeimfive
|
https://www.reddit.com/r/explainlikeimfive/comments/7ds6s3/eli5_why_do_lighters_have_smaller_flames_when/
|
{
"a_id": [
"dpzz9ho",
"dq03v1p"
],
"score": [
8,
3
],
"text": [
"Butane gets thicker when cold so it doesn't come out as fast so it only produced a small Flame. ",
"Butane boils at 30f degrees. The only reason it's a liquid is because the pressure forces it to be that way. When you hit the button, the open valve lets the butane literally boil and steam out. The lower the temperature, the slower the boil. Below 30 degrees lighters don't work at all because there's no pressure. "
]
}
|
[] |
[] |
[
[],
[]
] |
||
4hykti
|
how did charles manson influence his followers to do such drastic acts?
|
I just can't imagine people being convinced so easily without anything on the line for them or anything benefitting them.
|
explainlikeimfive
|
https://www.reddit.com/r/explainlikeimfive/comments/4hykti/eli5_how_did_charles_manson_influence_his/
|
{
"a_id": [
"d2th7xe",
"d2thr85",
"d2tjdp8",
"d2tnh5k"
],
"score": [
18,
4,
2,
2
],
"text": [
"The same way that Hitler did. He had a very strong charismatic personality that was capable of getting people to trust him, believe and follow what he said. \n\n > I just can't imagine people being convinced so easily\n\nAnd that is where you are wrong. People are very easily convinced of things and history is full of charismatic people taking advantage of it. ",
"TLDR: he offered runaways something their homes did not.. acceptance.\n\nThe long of it all, is based on two factors, Charles Manson's charisma coupled with the need for troubled and runaway teens to have a place they felt safe and like it was their home. The kids Charlie took in all left their homes because they didn't feel like they belonged or fit in... Charlie had a smooth tongue and an easy accepting manner that gave these kids a feeling of being wanted, important, part of something that was their own, not forced on them by their parents or society. Ironically, Charles manson has more followers worldwide today than he ever did when he \"inspired\" those kids to do those horrible things",
"The same way that Donald Trump keeps gaining popularity. Just tell them what they wanna hear and seem sincere about it. Once your in power, you can change the rules and anyone who doesn't follow is labeled a traitor.",
"Simple, \n \n \nThe same way people were convinced human sacrifice was good. \n \nSame way some people were convinced to mutilate people in the Inquisition, or torture people who translated the bible to english, or imprison people for saying the Earth is not the center of the universe. \n\nOr the same way people were convinced genocide was demanded by their god. \n\nOr the same way people were convinced to burn women alive for being witches. \n \n\nOr the same way people were convinced to kill and be killed for a desert there god died. \n \nOr the same way people were convinced that slavery was okay. \n \nOr the same way a soldier is convinced that blowing up a village full of brown people makes him a hero. \n \nOr the same way a Kansas family is convinced that picketing said soldier's funeral and harassing his loved ones will get them into heaven. \n \n\nOr the same way someone is convinced to strap a bomb to themselves or hijack a plane. \n \nOr the same way some people are convinced they are the superior race. \n \n\nOr the same way people are convinced to kill cartoonists or threaten authors. \n\nOr the same way people are convinced to not vaccinate their children. \n \n\nOr the same way young girls were convinced to run away from home with the messiah and be sexually assaulted. \n \n\nOr the same way some people are convinced to stone their children to death. \n\n Or the same way some people are convinced to waterboard other people. \nOr the same way some people are convinced to bomb hospitals and clinics. \nOr the same way some people are convinced to cut off their daughter's clitoris. \nOr the same way a police officer is convinced that shooting an unarmed person is normal. \n\nOr the same way people are convinced to hate another who is not like them. \n \nThe brute fact is we are, as a species still not entirely rational beings, and our emancipation from the rest of the animal kingdom is wishful thinking at best. \nBut if there's anything to be learned from a monster like Manson it's when he starts talking. \nIf you listen to him from his earlier interviews to his footage today, it's like looking at a time capsule; he starts spewing his cryptic beatnik dialogue with random spouts of biblical grandiose just like he did 40 years ago. Only now it seems he's just phoning it in. \nThe Manson then and Manson now have changed little, and THAT is why he was doomed from the beginning. He is the epitome of the evolutionary detour of all sociopaths. Swine like him come in all shapes, sizes, and colors; but inside they're ALL the same model; apathetic parasites that run on the pain of others. \nThey just had the bad luck of being born to a species who's success as a social animal that would work together in order to grow and survive the grinding passage of time. While the sociopath would only have to make sure he blended in, unaware that it's already too late because he was a fossil from the start.\nEither Manson is incapable of figuring this out, or he's terrified to admit it to himself in his most private thoughts. \n \nOr maybe he doesn't care. \n \nBut it doesn't matter, back in his heyday, Manson's mysterious warrior poet act was his choice hunting method of luring the young and impressionable. Even now he will still release his inner muse if he thinks there's attention, after all, in the end who is he? \n \n \n \nNobody"
]
}
|
[] |
[] |
[
[],
[],
[],
[]
] |
|
1ogjpf
|
what is final fantasy? what is the plot, and why is it so damn famous?
|
I seriously just don't understand the whole thing. Every time I try to understand it I end up with a headache.
|
explainlikeimfive
|
http://www.reddit.com/r/explainlikeimfive/comments/1ogjpf/eli5_what_is_final_fantasy_what_is_the_plot_and/
|
{
"a_id": [
"ccrqpta",
"ccrrn6z",
"ccrtiia"
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"score": [
10,
5,
2
],
"text": [
"Every one of them are almost completely disconnected from the others, so trying to think of them as a whole will make it really hard to get it. They all take place in different worlds, with different characters and different mythologies. \nThey do have a few common elements, but they're usually not very story-relevant so don't get too stuck on them.\nEssentially, every Final Fantasy game should be thought of as a stand-alone JRPG. \n\nFinal Fantasy built its fame on some of its very popular (and for good reason) earlier titles. I could be wrong, but I gather that 7 is the game that built the massive fame it now has, although it was still great before 7 came around; 6 has a pretty die-hard fanbase. \n\nThe general consensus is that it's been a very long time since the last \"good\" final fantasy game was released, many arguing that 10 was the last title in the series that was faithful to the original quality and spirit of the franchise, but there's some dispute on that. It seems that the general consensus is that Final Fantasy 6-10 were the games produced in the 'golden age' of final fantasy, but there's quite a lot of dispute even among those titles.\n\nTLDR: They're all different games, and the old ones made them famous enough that there's a lot of die-hard fans that still talk about them. Mix that with newer fans from the newer games and you get a lot of mixed messages.",
"From a historical standpoint, I believe that Final Fantasy was a last ditch effort by SquareSoft (now Square Enix) to produce a game because the company was going bankrupt. The franchise was enough to take a few steps forward early on, but really didn't explode until about FFVI, as others have said. It's famous for a lot of 90's gamers because SquareSoft did a really good job at getting the gamers to become emotionally invested in the characters and story. Sure, the stories are complicated and in a big world, but that's why there's a lot of appeal and a lot to experience. ",
"Final Fantasy is a collection of games that share a few themes, but almost always occur in completely separate universes.\n\nThese games are role playing games (RPGs) that are like stories/books/movies where you control the characters. Character development is central to the games. Character development occurs both in the story as you learn more about the characters' back-story and they go through the story, but also your characters become stronger as they go through the experiences. \n\nThe stories vary game to game, but you start off with your main character and (usually) gain friends that you also control as you go through the game. You have to fight enemies of various types as you go. You can defeat these enemies with a variety of physical attacks, magical attacks, self-enhancements, status attacks (like poison, sleep), and other special abilities. Each character normally has strengths and weaknesses of their own, so usually the optimal strategy is to maximize individual character's strengths and then balance your party (combination of characters). For example, you might have a character that has very strong magic attacks, but is very susceptible to physical injury when you have another character that is very durable to physical attacks and can make the enemy attack them. By making these characters co-operate, you can maximize the damage dealt while minimizing the damage you take. This is important when fighting enemies more powerful than your characters; you can't win unless they not only work together, but they must work together intelligently.\n\nIt is the character development (both in terms of story and attributes to make them stronger fighters) and the way the characters interact (story and also how they allow each other to maximize their own strengths while covering each other weaknesses) that is central to the experience.\n\nSee also /r/FinalFantasy "
]
}
|
[] |
[] |
[
[],
[],
[]
] |
|
4svnma
|
Asian exploration of America
|
With so much made of Europe's discovery of America, and additional discussion of whether there were pre-Columbian Atlantic crossings, I find myself asking why there wasn't more Asian crossing of the Bering Sea and Strait to explore, conquer, or trade. There were seafaring peoples in northern Asia. What was it about these cultures that made them less inclined to explore or expand? Or is it simply that they did and we don't hear about it or that they did but left little historical record?
|
AskHistorians
|
https://www.reddit.com/r/AskHistorians/comments/4svnma/asian_exploration_of_america/
|
{
"a_id": [
"d5cm5gp"
],
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"text": [
"Asian cultures did expand into North America. Migrations from Sibera and Alaska were particularly notable. The Thule started colonizing Dorset lands as late as the 1200s:\n\n_URL_1_\n\n\nThere are no written records of any of this, so it has to be pieced together through archaeological evidence. No ones even really sure what happened. There's no real evidence of mass violence between the Dorset and Thule, but we do know they didn't interbreed:\n\n_URL_0_\n"
]
}
|
[] |
[] |
[
[
"http://www.livescience.com/47604-first-american-arctic-people-genetics.html",
"http://www.jstor.org/stable/25470503?seq=1#page_scan_tab_contents"
]
] |
|
548802
|
What happened to the French Foreign Legion during WWII? Was the legion divided, or did most of the legion go to either side? Were there ever any attempts by Petain's government to establish a foreign legion from Axis Powers?
|
AskHistorians
|
https://www.reddit.com/r/AskHistorians/comments/548802/what_happened_to_the_french_foreign_legion_during/
|
{
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"d7zs1fc"
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"text": [
"I think this is a question that I can actually answer. I wrote my undergraduate thesis on the French Foreign Legion's demographics from 1914 to 2014. \n\nThe French Foreign Legion was very fractured during the Second World War. There was no central command that organized all of the different garrisons and formations of the Legion. You have Legionnaires fighting for the allies, for the axis and not fighting at all. Furthermore, they change sides depending upon France's status as a liberated/occupied state. \n\nA large part of the Legion fell under the command of the Vichy Government, who subsequently released 2,000 German Legionnaires to the Nazis. Most of them were communists, or of Jewish heritage. On a related note, when Italy joined the war, many of the Italian Legionnaires were sent back to their homeland. To fill the manpower shortages France ends up activating many elderly, unfit Legionnaires living in retirement. I should also note that not all German legionnaires were sent back to Germany. Germans made up an incredibly large part of the Legion's non-commissioned officers corps. In 1934, 44% of the Legion was German/German speaking and 21% of the NCOs were German/German speaking. This prevalence of German speakers actually alarmed the French government, who worried that if another war broke out that the Legion would be incapable of defending France from a German invasion. There were actual fears that the Germans were purposely sending young men to the Legion in order to subvert it. There is little evidence that this was the case, but the paranoia was sufficient enough that little in the way of material/emphasis was placed on the Legion in the years leading up to World War 2, and by 1939 it was a bent and broken sword that France would have much rather pretended did not exist. \n\nSo, you have some Legionnaires fighting for Vichy France. Those that were stationed in North Africa get folded into the German Afrika Korps. They fight in North Africa, and they fight in the Levant. When the Germans are defeated on that continent, many of the Legionnaires switch sides and begin fighting for the allies again.\n\nIn Asia, you have the French garrisons in Indochina. Eighty to one hundred Legionnaires escape European France and seek solace with the 5th Infantry Regiment in Indochina. The French forces in this part of the world sit out the war. They allow the Japanese to occupy Indochina, but are not taken into custody by Imperial forces. \n\nIn 1941, you have Legionnaires landing with the allies during Operation Torch (30% of them were Spaniards who had fled Spain when they lost the Civil War in that country). They had fought in Norway, and were under command of the *Armee d'Afrique*, which would go on to see service not only in North Africa, but Italy, France and even Germany. This is one of the fighting formations of the exiled French Government under Charles de Gaulle. \n\nNow, I must admit that I do not know what you mean by, \"...any attempts by Petain's government to establish a foreign legion from Axis powers.\" The best I can gleam off of that portion of your question is whether or not Petain's government accepted foreign volunteers into it's armed forces. I must admit, I am ignorant, but an educated guess based upon my research would suggest that the Legion under Petain was struggling to survive as a military unit; fending off the awkward attempts of the other axis powers to absorb it completely.\n\nSources: \n\nGeraghty, Tony. *March or Die: France and the Foreign Legion*. London: Grafton, 1986. Print. \n\nMcLeave, Hugh. *The Damned Die Hard*. New York: Saturday Review, 1973. Print. \n\nPorch, Douglas. *The French Foreign Legion: A Complete History of the Legendary Fighting Force*. New York, NY: Harper Collins, 1991. Print. "
]
}
|
[] |
[] |
[
[]
] |
||
3vaujo
|
In Greek mythology does Hades ever actually do anything morally questionable?
|
As the God of the underworld many people would associate him with evil however after my semester at school it seems that compared to Zeus and Poseidon, Hades seems to be quite tame and civil.
Has my teacher simply ignored any wrongdoing by Hades or did was he supposed to generally stay out of drama
|
AskHistorians
|
https://www.reddit.com/r/AskHistorians/comments/3vaujo/in_greek_mythology_does_hades_ever_actually_do/
|
{
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"cxly5cq",
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"text": [
"The story that immediately pops into mind is the [Kidnapping of Persephone](_URL_0_). Hades takes Persephone, daughter of Zeus and Demeter (God of Agriculture), as his wife against the wills of Zeus and Demeter. Demeter falls into deep anger and brings famine across the world and will not relent until Persephone is returned. Hades relents, but not before tricking Persephone into eating a Pomegranate seed, forcing her to remain in the underworld. In a compromise, Zeus' mother said that Persephone will spend 6 months with Hades and 6 months with Demeter each year. This is the explanation story of the seasons. This easily falls under Morally Questionable.",
"The underworld having any kind of \"evil\" connotation was not present in Greek culture. After all, there was no heaven. Everyone goes to the underworld upon death. Virgil's Aeneid explores different tiers of the underworld where people would go depending on good or bad deeds, but Virgil was a a Roman author who came much later. \n\nAnother reason for any lack of evil deeds is that there just aren't that many myths about Hades in the first place. Even the few things he does that seem evil (kidnapping Persephone) are pretty tame compared to things done by other gods. \n\nArtemis turned a man into a deer and had his own hunting dogs tear him apart because he saw her bathing. \n\nArtemis and Apollo shot all 19 or so of Niobe's children to death because she bragged that having more children than Artemis and Apollo's mother made her superior. \n\nHera struck Tireseis blind because he favored Zeus' side when asked to settle an argument between them. \n\nHera has Ixion bound to a spinning wheel for all eternity in the underworld because he bragged about having sex with a cloud version of her. \n\nA lot of myths involve gods being evil to humans. Hades actually comes out pretty nice looking simply by not being involved in many myths. "
]
}
|
[] |
[] |
[
[
"http://www.infoplease.com/cig/mythology/hades-takes-wife-persephone.html"
],
[]
] |
|
dnq99g
|
Why did agriculture develop independently all over the globe in the last 10000 years but not before?
|
AskHistorians
|
https://www.reddit.com/r/AskHistorians/comments/dnq99g/why_did_agriculture_develop_independently_all/
|
{
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"f5gf1js"
],
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"text": [
"Before that time period was [the last Ice Age](_URL_6_), which lasted for many thousands of years. The climate was so arid and difficult to survive in that it was not really possible for anyone to survive in one place long enough to discover & develop agriculture, since these groups of people were required to move around to be successful at [hunting & gathering](_URL_4_). \n\nThere has been no evidence found of any type of homonids knowing how to cultivate plants before the last Ice Age, in the previous warm period ([the preceding interglacial](_URL_3_)), since only materials like bones and rocks can survive over such a vast amount of time. However, it is fairly safe to say that it is unlikely that they understood how to cultivate plants on a meaningful scale that early in their development. In addition, it is believed that there were relatively few homonids in the previous interglacial ([the Eemian](_URL_2_)), so it is likely that the naturally-occurring amounts of plants and animals could sustain a small, thinly-spread population without plant cultivation being neccessary. \n\nHowever, after the worst of the last Ice Age ([the Last Glacial Maximum](_URL_1_)) was finished, the climate began to warm up to the point that our planet entered the current warm period called the [Holocene](_URL_0_). Over several thousand years, this reliable climate has allowed humans enough stable, warm weather to stop surviving by only hunting and gathering, and to settle down and discover new ways to survive, such as agriculture, animal husbandry and new technology. \n\nAs the human population slowly [increased over the last several thousand years](_URL_5_), the naturally-occurring amounts of food were not able to sustain the larger population, and much of the available arable land was occupied. Therefore, people found that it was increasingly desirable to aquire more food from their own land instead of fighting with other people (wars) over food supplies, so cultivation of plants became more and more necessary, causing the rise of agriculture in many different areas."
]
}
|
[] |
[] |
[
[
"https://ucmp.berkeley.edu/quaternary/holocene.php",
"https://www.britannica.com/science/Last-Glacial-Maximum",
"https://www.ncdc.noaa.gov/global-warming/penultimate-interglacial-period",
"https://www.sciencedirect.com/topics/earth-and-planetary-sciences/eemian",
"https://www.ancient.eu/article/991/prehistoric-hunter-gatherer-societies/",
"https://youtu.be/PUwmA3Q0_OE",
"https://www.livescience.com/40311-pleistocene-epoch.html"
]
] |
||
3no6cg
|
why do cultures who rely heavily on rice in their diet typically use white rice which has less nutritional value than other types of rice?
|
explainlikeimfive
|
https://www.reddit.com/r/explainlikeimfive/comments/3no6cg/eli5why_do_cultures_who_rely_heavily_on_rice_in/
|
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"One of the reasons why Asians have used mainly white rice over the years is that white rice lasts longer in storage than brown rice. The essential fatty acids found in brown rice usually begin to go bad after approximately 6 to 12 months of storage, the exact amount of time depending on how much oxygen is available. When brown rice is polished down to make white rice, many of the essential fatty acids are lost, allowing white rice to last longer than brown rice without going bad.\n\nAnother reason why many Asians prefer white rice is that they have become accustomed to how easy it is to chew and digest. Brown rice requires more chewing power to properly digest than white rice does.\n\nSome Asians refuse to eat brown rice because to them, it's a sign of poverty. Many Asians who are above 40 years of age have been deeply conditioned to believe that prosperous people eat white rice while peasants eat brown rice.\n\nFinally, many Asians choose white rice over brown rice because white rice is less expensive. White rice is far less expensive to produce and distribute because it is in greater global demand and produces higher profits because of its longer shelf life.\n\n[Source](_URL_0_)",
"Brown rice still has the bran and germ on it. This is what makes it more nutritional than white rice, but it also means that it will spoil much faster than white rice will. \n\nIf you are wondering about the product called \"Wild Rice\". That is not a true rice and is a crop native to Northern North American and so was not an option to be used by the rice cultures of the world. ",
"Cajun here. I imagine for us, it's just the flavor. Brown rice is a bit more vegetal, which IMHO doesn't go well with most of our traditional cuisine; most of our rice-based dishes are salty/savory.",
"As a side note I remember a documentary stating that in many areas the people who farm white rice actually typically can't afford to each much of it and instead they eat... I don't remember I want to say lentils? It was something cheaper anyway.",
"Brown rice doesn't taste as nice. Same reason Americans generally prefer white bread and potatoes.",
"In my culture (spanish), we mainly use white rice as its our staple food (rice, beans & meat). It mixes better when we add other ingredients to it, i.e making Seafood rice, beef, chicken & other meats. It absorbs the flavors better. Brown rice has its own unique taste and it alters thr flavors that we really need to achieve. Its less expensive than brown rice & as other people have stated, it lasts longer. ",
"The phytic acid in whole grains actually impairs absorption of dietary minerals and increases digestive issues. So the increased mineral content that you get from whole wheat, brown rice, etc is moot--you aren't absorbing those minerals anyway so you may as well eat the refined grains which are 1) easier to digest 2) have superior culinary properties 3) last longer in storage without spoiling. Whole grains also have more vitamins than refined grains, however in the last century we've been fortifying refined grains to the point where they're now higher in vitamins than the whole grains, and besides grains are a weak source of vitamins compared to fruits and vegetables, dairy, and meat.",
"As far as I know, brown rice may be more nutritional, but the bran contains phytic acid, a so-called anti-nutrient, which prevents the body from absorbing the nutrients. This makes the net nutritional value of white rice actually greater than that of brown rice.",
"For what it's worth, cultures who rely heavily on wheat in their diet typically use white flour rather than whole wheat, despite nutritional loss.",
"chinese here. i was the first one to be born in america but my parents are from mainland china and were raised old school. all i've ever eaten were homecooked traditional chinese food (they both cook amazing food), white rice every single day for dinner. both of them were very very poor growing up and they never ate brown rice. \n\ni don't know what the top commenter is talking about being a sign of poverty. i asked my parents why they dont eat brown rice and they say it's because it tastes like shit, and i agree with them. brown rice also doesn't go well with the side dishes we eat, white rice just taste much better with them.\n\n**edit:** for those saying white rice has no nutritional value and full of sugar may be true BUT that doesn't mean eating it makes you unhealthy by any means. i'm not obese at all, im 5'10 190lbs and i eat white rice every day, alot of it (sometimes for lunch as well as dinner). i bench 325, squat 385, deadlift 405. being \"healthy\" is a relative term. i obviously don't fill my daily calorie goals ALL on white rice, i get more nutrients elsewhere (veggies, beans + wheat bread for fiber, lean meats, fish, etc etc etc) , so you can't say white rice makes you \"unhealthy\". plus, my mom and dad eats it several times a day and they're skinny and healthy.\n\ni also didn't know brown rice was associated with poverty because i didn't pry my parents with the question. simple question \"mom, dad, why don't we eat brown rice\", them \"because it taste like shit\", me \"oh ok\".\n\nTLDR for edit portion: the biggest misconception people have is that white rice is full of sugar and has no nutritional value, therefore it's bad for you and will make you unhealthy/obese. no, it doesnt work that way.",
"Chinese from Singapore here.\nHonestly, like what some of the comments here have stated, brown rice just tastes weird. It's bitter and feels like you're eating nuts but well, you're not. Perhaps it is due to cultural conditioning, but to me, it doesn't go well with the Chinese dishes. It doesn't have the slight sweetness white rice have after it is cooked nor does it mix well with the dishes.",
"simple, keep white rice dry and it will pretty much be eatable forever, brown rice will go off in a couple months no matter what you do.\n\nalso brown right is just gross =p\n",
"Brazil here. We eat white rice and black beans every day.\n\nFirst of all it's just a matter of habit - I'm not sure what's the cultural reason that drove our ancestors to eat white rice, but there's a whole factor here of we eat it like this because it's always been how we eat it.\n\nHowever, an important factor is the fact that rice is *always* viewed as a non-obstrusive *complement* to whatever other thing you are eating. So when you eat a typical *feijoada* (a big meal made with black beans and, well, everything you can possibly remove and eat from a pig, including his ears, tail, legs and such), you'll add white rice to it, adding substance, but not intruding the flavour. Whole grain rice would have too much \"personality\" on the dish and distract from the main point, which is the beans.",
"Brown rice technically contains more nutrients, but you don't necessarily get those nutrients because it's harder to digest compared to white rice. \n\nHere's a quote from Chris Kresser with reference links below in case anyone is interested:\n\"Aside from having a higher arsenic content, there are other reasons to avoid brown rice: it’s harder to digest and nutrient absorption is likely inferior to white rice because of phytates in the rice bran. (8) Despite a higher nutrient content of brown rice compared to white rice, the anti-nutrients present in brown rice reduce the bioavailability of any vitamins and minerals present. (9) Plus, brown rice also reduces dietary protein and fat digestibility compared to white rice. (10)\"\n\n(8) _URL_2_\n(9) _URL_0_\n(10) _URL_1_",
"I think it has to do with the fact that white rice lasts longer. If you look at a package of brown rice you'll see that it goes bad, or has to be refrigerated.\n\nThe ability to store a staple food (i.e. rice) for long periods of time was probably a cornerstone of many civilizations. It meant that people were less likely to starve to death because they could stockpile white rice for long periods of time.",
"You could ask the same question, why do americans eat white bread, when whole wheat is better for you? ",
"Brown rice can not be stored for long periods of time without going rancid. So that is the probably the practical reason for a preference for white rice.\n",
"Is brown rice really that much better for you, or that just some fad nutritional advice, not based on solid science, that will be reversed in 10 years?",
"Indian here.\n\nIt's for the same reason white-bread was traditionally considered rich-people-food while brown-bread was considered poor-people-food in Europe. (Apparently French Revolution outlawed bread-segregation, and forced \"mixed-breads\" for everyone, not sure whether this is true or not).\n\nIt's because white rice is softer, easily digestible, easily made into flour (which can be used to make rice-cakes, rice-pancakes etc.), can be easily made into desserts like rice-puddings. White rice has a neutral flavor that easily picks up the fragrance of herbs and spices it is cooked with, whereas brown rice is very \"adamant\" in the sense that it has it's grassy-hay-like flavor that overpowers other tastes. Brown rice is like the stubborn child who doesn't want to play with other children.\n\nBrown rice and red rice were traditionally eaten by poor who couldn't afford white rice. Today brown rice is becoming more popular with the fitness and health gaining more awareness, but white rice remains the default staple."
]
}
|
[] |
[] |
[
[
"http://drbenkim.com/node/82"
],
[],
[],
[],
[],
[],
[],
[],
[],
[],
[],
[],
[],
[
"http://www.ncbi.nlm.nih.gov/pubmed/9302338",
"http://www.ncbi.nlm.nih.gov/pubmed/2822877",
"http://brianstpierretraining.com/index.php/brown-rice-or-white-is-there-really-a-difference/"
],
[],
[],
[],
[],
[]
] |
||
d94a75
|
how a gamma ray burst could kill us all at any moment
|
explainlikeimfive
|
https://www.reddit.com/r/explainlikeimfive/comments/d94a75/eli5_how_a_gamma_ray_burst_could_kill_us_all_at/
|
{
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"f1eikjq"
],
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"text": [
" Gamma ray bursts occur when very dense stars die and go supernova - basically, they explode. If such a star were to explode close enough to our Solar System, dangerous gamma rays would bathe the Earth, killing us off - think a dangerous nuclear leak, but on a cosmic scale.\n\n The odds of a gamma ray burst affecting us are astronomically small, however, so don't let that fact keep you up at night."
]
}
|
[] |
[] |
[
[]
] |
||
8jcuvt
|
Does losing sight in your right eye affect the functioning of the left side of the brain? and does this only impair your eyesight, or are there other implications ? [effectively you are reducing the input of visual information to the left side of the brain, thus reducing its functionality ]
|
askscience
|
https://www.reddit.com/r/askscience/comments/8jcuvt/does_losing_sight_in_your_right_eye_affect_the/
|
{
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"dyzbbdq"
],
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"text": [
"It is a common misconception that the image from the left eye is processed in the right hemisphere of the brain, and vice versa. In fact, it is the left half of your *visual field* that is processed by the right hemisphere (i.e. everything to the left of the center of your gaze), and vice versa. So both hemispheres actually receive input from both eyes. You do see a little further to the left with your left eye, and a little further to the right with your right eye, but most of your visual field has coverage from both eyes. Importantly for your question, this means that after going blind in one eye, both hemispheres still receive roughly equal amounts of visual input (visual input is lost, but it is lost from both hemispheres).\n\nLosing sight in one eye will affect your depth vision somewhat, because you lose binocular disparity as a depth cue. However, there are many other [cues for depth](_URL_0_) that the brain uses, so you'll still be able to navigate the world with very few problems, although you may find it harder to catch a ball (for example).\n\nOther than that I don't know of any additional side-effects."
]
}
|
[] |
[] |
[
[
"https://en.wikipedia.org/wiki/Depth_perception"
]
] |
||
totmj
|
Is it possible for a planet to be larger than the star that provides light for it, so that the sun revolved around the planet?
|
I hope this hasn't been answered already... I just had a philosopher moment sitting here on the couch.
|
askscience
|
http://www.reddit.com/r/askscience/comments/totmj/is_it_possible_for_a_planet_to_be_larger_than_the/
|
{
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"c4oh21c",
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"text": [
"Actually, regardless of the relative sizes of the sun and the planet, both would orbit around their combined center of mass. It's just that when one is much bigger than the other, the combined center of mass is very close to the center of mass of the larger body. For simplicity and convenience, it is often said that the small one orbits the large one, while in fact both orbit each other. [Here](_URL_0_) is a diagram of the combined center of mass of the entire Solar System relative to the Sun.",
"This really depends on what type of star you are talking about. A star undergoing fusion will be much more voluminous than a dead star or any planet. However a white dwarf, a type of dead star, will have a volume comparable to the Earth. It will still be as massive as a typical star, which is much more massive than a planet. \nSo if a Jupiter type planet orbited a white dwarf, it would be more voluminous and less massive than the star it orbits. edit: So the planet would still always orbit around a star. Brown dwarfs make this complicated since they are failed stars and may be near the mass of a star. In that case they would orbit a distinct barycenter outside the volume of either.",
"In fact, one of the very first extrasolar planets discovered was around a pulsar, [PSR B1257+12](_URL_0_). Pulsars are incredibly small and incredibly dense, and PSR 1257+12 is no exception: despite having a mass 1.5x our sun's, it has a radius of only 14 kilometers. \n\nHowever, calling a pulsar a star is a stretch. They are held up against gravitational collapse by neutron degeneracy pressure, not nuclear fusion. So any planet around a pulsar is going to be near 0 K in temperature. And neutron stars are formed by the collapse of massive stars, which means any planets in orbit had to weather a supernova sometime in the past."
]
}
|
[] |
[] |
[
[
"http://upload.wikimedia.org/wikipedia/commons/thumb/0/0c/Solar_system_barycenter.svg/1000px-Solar_system_barycenter.svg.png"
],
[],
[
"http://en.wikipedia.org/wiki/PSR_1257%2B12"
]
] |
|
5tro1q
|
why do roads appear more curved as i drive on them compared to the way they appear on maps?
|
[deleted]
|
explainlikeimfive
|
https://www.reddit.com/r/explainlikeimfive/comments/5tro1q/eli5_why_do_roads_appear_more_curved_as_i_drive/
|
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2
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"text": [
"Scale. \n\nWhen driving if the road curves ten feet you will feel it. \n\nTo a map maker that small curve doesn't matter when they draw the road. \n\nSame thing with hiking trails. I've been on some flat trails that simply just did small ups and down. \n\nif the turn isn't large the map won't record it. "
]
}
|
[] |
[] |
[
[]
] |
|
1dki3a
|
what actually decides when i'm born if i'm a boy or a girl?
|
Sperm, egg or other?
|
explainlikeimfive
|
http://www.reddit.com/r/explainlikeimfive/comments/1dki3a/eli5_what_actually_decides_when_im_born_if_im_a/
|
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"sperm have an X or Y chromosome. Eggs always have X. if you get a Y sperm you're going to be a male, if you get an X sperm you will be female... this only applies to humans (maybe some other mammals, I'm no expert)",
" > The sperm cell determines the sex of an individual in this case. If a sperm cell containing an X chromosome fertilizes an egg, the resulting zygote will be XX or female. If the sperm cell contains a Y chromosome, then the resulting zygote will be XY or male. \n\n[From here.](_URL_0_)",
"Your dad's sperm.\n\nYour DNA (the blueprints to build a complete human), is broken up into like little chapers, called chromosomes. Everyone has two copies of all 23 chapters. Or you have 23 chromosomes from mom (the egg) and 23 from dad (the sperm) for a total of 46 (you need all 46 for everything to work but thats another ELI5).\n\nNow of those 23 (remember you have a copy of each) only one determines sex, #23, the sex chromosome. \n\nAll fetuses are defaultly female, the only thing that makes them into a male is two certain hormones at very specific times. The codes to make these hormones are found on a chromosome called Y. \n\nSo lets do some deductions. If Y is the chapter than makes the \"turn this baby chick into a baby dude\" signal; and your mom isn't a dude, then she doesn't have Y. She has the Y's female copy, called X. Actually remember she has two X's (every chromosome has a copy). She got one X from her mom and one from her dad. No Y, so no signal to make a dude, so when she was an fetus it defaulted to a female, the natural sex.\n\nSo when her eggs are formed and she gets to give one of her copes, she can only give an X, thats all she has. But you dad, he's a dude, so he as an Y, and since he's from a man and woman, the other #23 he has is an X. So when his sperm form there is a 50/50 chance it gets an X copy or a Y copy.\n\nSo its the sperms, with its X or Y than when it fertilizes the egg, which can only have an X, that makes the sexual determination. ",
"It's determined by the [23rd chromosome](_URL_0_) in the sperm. It can be an X or Y chromosome. The reason being a boy or a girl doesn't depend on the egg is because eggs always have an X chromosome. So if you have a Y chromosome from the sperm, you get an XY combination which means you get a boy. If the sperm has an X, you get an XX combination which makes a girl. \n\nShort answer, it's decided by which sex chromosome the sperm carries.",
"Thanks everyone, I get it now :). ",
"Usually a few inches of skin."
]
}
|
[] |
[] |
[
[],
[
"http://biology.about.com/od/basicgenetics/p/chromosgender.htm"
],
[],
[
"http://www.in-gender.com/XYU/Conception/Pix/karyotype_sperm.jpg"
],
[],
[]
] |
|
ax4oys
|
what happened in world war 2, and why did it happen?
|
explainlikeimfive
|
https://www.reddit.com/r/explainlikeimfive/comments/ax4oys/eli5_what_happened_in_world_war_2_and_why_did_it/
|
{
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"1. War happened. You'll learn more when you reach middle school and take your history lessons. \n\n\n2. Because we treated the Germans really badly after WW1 they elected a Adolf Hitler, a known power tripper, as their leader who eventually attacked Poland starting the European front, and because the Japanese were also on a really huge power trip and attacked basically whole of Asia and America starting the Pasific front. ",
"Its a bit hard to explain but basically.\n\nWhen WW1 ended there was the Versailles treaty which basically blamed Germany for the war and had them pay war reparations to all allied countries with exception of Russia since they abandoned the fight in 1917, They were also forced to give up part of their industrial production to France as part of reparations. \n\nThe issue is that to pay for the war all European powers were borrowing money from the US, and were heavily in debt.\n\nThis was fine because the US was giving them a stable payment plan... Until the 1929 stock market crash... the US recalled all loans and raised interest rates. leaving Europe with no financial liquidity.\n\nThis basically meant that the whole of europe was plunged in to a financial crisis, but the hardest hit was germany due to several factors. \n\nTheir economic reserves were forfeit when the lost the war, much of their industrial output was going to pay off the allied powers and the new Wiemar republic government was a bit green and decided to try to improve the financial situation by printing more money. \n\nAt the same time the first \"soviet expansion projects\" were on the horizon and some support was going to communist groups in Europe, which meant that many governments had to either ally them or with Fascist and at the time resentment with the soviets from abandoning WW1 as well as general dislike of the ideology meant that governments were much more trusting of Fascist parties then communist revolutionary groups. \n\nAt the same time a ww1 \"war hero\" (he didnt do much but he was in the trenches and wounded) by the name of Adolf Hitler was taking over a small Bavarian nationalist party that grew to be the the national socialist party, AKA the Nazi party.\n\nThey got a respectable parliamentary representation on a plataform of blaming external powers (allied powers, jews, bankers) of the economic problems in germany, ceasing payment of all war reparation, retaking the industrial areas and output which was given to France. and a major public works program to rebuild german infrastructure.\n\nThey manged to take full control of the parliament after they were given emergency powers due to a false flag operation where they torched the parliament and blamed communist and anarchist for it. \n\nThe idea is that between no longer paying war reparations, and a expansion plan in to eastern Europe which was agreed with Stalin, Germany could finance all its public infrastructure plans and slowly take over europe creating a pan european german empire. \n\nBut both england and france had defense treaties with poland, at first when germany took over Czechoslovakia there were appeasment treaties, which ment that germany would be allowed to expand inside a limit to avert all out war. \n\nBut when Germany invaded Poland, the UK and France were forced to declare war on Germany and the 2nd world war started. \n\nBut this is the european theater of WW2, The Asian theater has been going on since the 1933 from the Japanese invasion of China, Korea and Indochina (whats today Vietnam, Laos and Cambodia)"
]
}
|
[] |
[] |
[
[],
[]
] |
||
321seg
|
Have regulated languages evolved as much as English?
|
I've often wondered if languages like French and German, that have a governing body, would evolve as much, or potential even more, than the English language has.
|
AskHistorians
|
http://www.reddit.com/r/AskHistorians/comments/321seg/have_regulated_languages_evolved_as_much_as/
|
{
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"**short answer:** No, not usually.\n\n**long answer:** It's important to remember that even though there are these \"governing bodies\", perhaps most famously L'Académie française and Real Academia Española, they don't actually hold power over people's speech. There was some recent news about the Swedish Academy updating their dictionaries and a lot of people (on Reddit) were upset because they saw it as the government saying certain slang words were now encouraged, but that's not actually the case. \n\nThe Academies, generally speaking, have two functions:\n\n1. Document the language, to include changes in usage or new vocabularies. This is particularly useful when a country (Republican China in the 1930s being a great example) needs to standardise terminology for things like the [STEM fields](_URL_0_), when before that point everyone's kinda using their own translation of foreign terms, if not just the foreign terms as they were in the original language.\n\n2. Determine and maintain the standard form of the *prestige dialect*, the form used for academic publication, passing of laws, official documents and the like. This is what we refer to as a [register](_URL_1_). How you speak with your friends out drinking at the bar is another register. How you talk to your elderly grandmother is another register. When you're writing an essay to get into college, it's not that they're testing how \"correct\" your use of the language is (even though that's what they themselves might think they're doing) but rather they're checking your ability to use that register effectively. For some people, switching registers is actually not something they have much experience with. \n\nHowever when it comes to natural speech, these Academies have little influence, and the language continues to change. The extreme case would be that the Academy-dictated register stays the same for so long that people stop associating it with the thing they're speaking. However that mostly doesn't happen because the people running these Academies have some sense and they do adjust to changes in usage when they become more widespread.\n\nLanguages change. There are some things that accelerate or reduce change. For example languages in contact with other languages will change a bit quicker regarding certain features. We see this tied to wars and historical migrations, not just in the sense of one group conquering another, but also in peaceful migrations where aspects of one language have been adopted by another, or where two languages with two different complex ways of handling the same function tend to merge resulting in a much simpler single way of doing that. I can give you specific examples from history but it's all going to be in East Asia, so let me know if you're interested.\n\nAdditionally, languages/varieties with fewer speakers have greater potential for change if there's nothing unifying them (mass media for example) because the naturally occurring changes can pass through the group more easily. You see this in places like Albania which is tiny but had huge diversity of dialects simply because for a very long time people stayed in and around their villages, effectively isolated, and without pressure from other dialects to maintain some conformity.\n\nThe way you could argue that the Academies, or lets even just say \"standard dialects\" slow things down is really if you only look at the group of speakers who are well off and in power. However even then it's largely not really there but is just their perception. As a loose rule in sociolinguistics: everyone thinks their dialect matches the standard, even when it verifiably doesn't.\n\nHope that helps. Let me know if I can expand on anything."
]
}
|
[] |
[] |
[
[
"http://en.wikipedia.org/wiki/STEM_fields",
"http://en.wikipedia.org/wiki/Register_%28sociolinguistics%29"
]
] |
|
2ra54c
|
what is a financial audit ?
|
Minimal to no jargon please. I wish they taught me this in school.
Edit: typo on 'wish'
|
explainlikeimfive
|
http://www.reddit.com/r/explainlikeimfive/comments/2ra54c/eli5_what_is_a_financial_audit/
|
{
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"Somewhere along the lines you filed some paperwork with the government saying how much money you made that year. The government blindly accepts that information as true and uses that to figure out how much taxes to charge you. An audit means they are going to double check to make sure that everything you said was true. If you were dishonest or forgot some information you may have to pay back-taxes.",
"I am going to assume that you have no knowledge of accounting so sorry if any of this is condescending.\n\nA financial audit looks at \"books\" kept by a business. A business keeps books to know all about how its money works. Like, how much money it makes each day, how much it spends, how much inventory, how many accounts it can collect.\n\nLike, if you are a restaurant you will keep a book that talks about all the sales you make. Another says how much salary you pay. Another says how much debt you have, and how much your chairs are worth and stuff like that.\n\nThis is done so that you can say \"I am making X dollars\" or \"I am worth Y dollars\" or whatever. A successful business makes money, while an unsuccessful business loses money. (This is incredibly simplistic but I dont think you want all the details here)\n\nWhen an audit happens you hire someone to come in and look at all your books. You usually go to a well known and respected firm to do it. They make sure you are truthful. If you say you make 10k a day, they will look at your bank deposits and make sure that is happening.\n\nAt the end, they issue an opinion. They say \"this business is telling the truth\" to the best of their ability to say so. This is done so that when you go tell a bank \"hey I need 100k to build a new section for seating!\" you can take your books and audit and show them that you are making enough money to pay the money back. "
]
}
|
[] |
[] |
[
[],
[]
] |
|
1rsg79
|
a grenade explosion
|
Why can such a small thing do so much damage? Why does it go BOOM like this? Why won't it explode immediately?
|
explainlikeimfive
|
http://www.reddit.com/r/explainlikeimfive/comments/1rsg79/eli5_a_grenade_explosion/
|
{
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"cdqe6em"
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" > Why can such a small thing do so much damage?\n\nExplosives are designed to be just that. You stuff explosives into a small, contained space and it makes it even more violent. The case is made of thick steel, so when the explosion ruptures it, it throws shrapnel all over the place and tends to make quite a mess.\n\n > Why won't it explode immediately?\n\nThere is a fuse that times it so that it takes several seconds for it to explode. Thus allowing enough time for someone to throw it and take cover."
]
}
|
[] |
[] |
[
[]
] |
|
6r4wux
|
What is the environmental impact of air conditioning?
|
My overshoot day question is this - how much impact does air conditioning (in vehicles and buildings) have on energy consumption and production of gas byproducts that impact our climate? I have lived in countries (and decades) with different impacts on global resources, and air conditioning is a common factor for the high consumption conditions. I know there is *some* impact, and it's probably less than other common aspects of modern society, but would appreciate feedback from those who have more expertise.
|
askscience
|
https://www.reddit.com/r/askscience/comments/6r4wux/what_is_the_environmental_impact_of_air/
|
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"Air conditioning is a pretty big issue. \n\n\nFirst it is the reason big cities in southern Arizona can even exist(along with the massive increase in urban/suburban sprawl and it's resulting carbon footprint in those areas). \n\nSecond is the peak demand on electric grids is high afternoon when the heat/people are out and about. So huge power demands from not clean not sustainable energy sources(which is a problem we have the technology to address should government/corporate policy measures reflect an interest in doing so). \n\nThird is they aren't all that energy efficient. Which could be addressed but is sidelined compared to issues one and two. ",
"In Drawdown, a book that describes 100 solutions to global warming, Refrigerant Management takes the top position. Refrigerant Management includes air conditioners and refrigerators.\n\n_URL_0_",
"Very big due to the energy used - China is putting a lot of effort ( subsidies and regulation) into efficiency mandates, and the market demand = business = jobs, into the highest efficiency standards and clean generation. \n\nYes a lot of people will say China is building more coal plants all the time - and yes this is true, but they are building up their infrastructure ( it's a electricity vs no-electricity issue), and they are cancelling a lot of these projects as they get larger base of wind and solar.",
"Air condition uses 18% of electricity in US homes, which is first on the list:\n[_URL_1_](_URL_0_).",
"People have mentioned that the amount of energy going to air condition is large, and that it is the primary driver of how much power plant capacity we need - peak power production, those are the two main power grid/engineering impacts that I know of.\n\nThe escape of the refrigerants used in air conditioning which are strong green house gases themselves is another impact.\n\nSomething I find interesting is due to cheap power and other priorities we have stopped designing our buildings to take advantage of local environment. For example Ancient Rome had the Justinian Code forbidding anyone from building tall enough to block their neighbors sunlight - something that we are having legal proceedings in the US today in regard to neighboring buildings and solar power production.\n\nAnother cool ancient concept that i cant remember the name of is free air conditioning by using a chimney to draw air up from underground. \n_URL_0_\n\nMovements like Passive House are moving people back towards designing buildings to take advantage of free energy.",
"Well, Drawdown ranks refrigerant management as the #1 most impactful thing we could do to help the climate, and a huge and growing fraction of that need comes from air conditioning.\n\nTheir rankings:\n_URL_0_\n",
"I was wondering about architecture recently. Lots of new buildings are made to be fancy but no regard toward heat diffusion. They're just oven in disguise, while old ones were able to delay heat waves enough to stay cool enough in the day and mildly warm at night.\n\nShould this be the default rule in building ?",
"I think one problem that is often overlooked is that buildings aren't designed with energy efficiency in mind. For example, why are the roofs on many homes black asphalt shingles? That's one of the worst materials when it comes to heat absorption. Wouldn't you want a light colored material that reflects most of the sun's energy? Also many homes still use the old style loose fill insulation which is a terrible insulator compared to modern spray foam insulation. ",
"A huge issue is the very rapidly growing middle classes in high population countries, especially China and India, where many, many millions of people can now afford air conditioning. Let's say 1% of the population adds air conditioning every 5 years, and on average 5 people live in each house. The combined population of China and India=2.7 billion X 0.01 (1%) / 5 = 5.4 million new air conditioned houses or about 1.1 million/year. Think of the new energy consumption demands, mineral resource demands, etc.",
"Buildings is the thing I have some background, so I'll mostly stick to that.\n\nBuildings account for between 20 and 40 percent of total energy consumption worldwide, (37% within the EU according to one study, ~40% in the United States according to the US Energy Information Administration)\n\nHeating and cooling account for 48% of residential energy use, and about 40% of commercial energy use in the US. \n\n**Thus, very roughly 16% of all energy used in the United States is used for heating and cooling buildings.**\n\nThat's only on the energy demand side, others have mentioned the problems with ~~Hydrofluorocarbon~~ chlorofluorocarbon Refrigerants and their effect on the ozone. The practice of freely releasing these Refrigerants into the atmosphere was banned years ago in the United States, and their use is somewhat restricted now IIRC.\n\nHeating in some places uses natural gas directly, and sometimes uses it indirectly according to the source of energy in the region.\n\nAside from the production and use of refrigerants in car AC systems, the energy used, in my understanding, is produced by the engine and converted to electricity via an alternator. It is my understanding that comparatively little energy is used for this, when compared to the energy consumed actually moving the vehicle.\n\n It might be noted that in the US, the energy used for transportation accounts for some 30 percent of total energy expenditure, and I don't think I need to talk about the environmental effects that the exhaust has.",
"Bigger than the electricity impact is actually the greenhouse gases emitted. GWP or global warming potential measures how much a trapped greenhouse gas heat up the atmosphere. All refrigerants have hundreds or thousands of times the GWP of carbon dioxide. Some common ones are R-11 (4750) and R-22 (1810). For reference, CO2 is 1. [Here's a list](_URL_1_) that you can scroll down and look at the \"net GWP 100-yr\" column.\n\nSo every time that HVAC systems leak (which is all the time), they are leaking gas that is literally hundreds or thousands of times more harmful to the atmosphere than carbon dioxide. They are constantly inventing new formulas that are better, but they are all basically really bad for the atmosphere in terms of GWP.\n\n[Refrigerants are also really bad for the ozone layer.](_URL_0_)\n\nIn fact there was a summit recently that said the #1 best solution to curb greenhouse gases was to focus on HVAC/R. I wish I could post a link but I'm having difficulty finding it.\n\nSource: am a software developer in the HVAC/R industry.",
"You've already got the answer you're after so I'll just say this: As a general rule most energy is used for heating and cooling. This includes stoves, AC, heaters, fridges, ovens etc. If you can reduce how much heating and cooling you're doing whether it's by using blankets or insulating your house better, then you will lessen your environmental impact. ",
"I think one of the biggest impacts isn't just environmental, but geographical. Specifically where people live. Until the advent of air conditioning the hotter parts of the earth were more sparsely populated. Now they're more full. The US South is an example of this. The population has grown considerably since AC because there's plenty of land there and plenty of space to move into. It means that I can live in what's essentially a sub-tropical rain forest area and not cook to death on 100 degree days.",
"/u/buddaycousin mentioned that in the US 18% of all electricity that is used in homes is used for air conditioning. However the overall impact on the electric grid is much bigger than 18%. That is because the needed capacity of the electric grid is depends on the peak usage. 18% of electricity used in US homes is used for air conditioning but that is on average for an entire year. But this 18% is mostly concentrated in the summer, during the day and when there's a heat wave. That means that the impact on the peak usage will be more than 18% and since the electric grid must be able to supply enough current for all this air conditioning the total impact on the size of the electric grid is much more than 18%, if I had to guess maybe 40% but this could be way off. Hope my explanation is clear enough. ",
"Energy consumption is one aspect, as already pointed out. But there's also indirect emissions due to the GWP (Global Warming Potential) of the refrigerants currently in use. As well as the break down components associated with newer refrigerants. \n \nI work in industrial refrigeration, we mainly deal with ammonia and carbon dioxide and we've been trying and successfully winning over small to medium sizes businesses to go to a low charge ammonia system to conserve energy.",
"additionally Ive always wondered what the impact on the environment is from moving all that energy to the inside/outside. like if i had 100 refrigerators, it had to pump heat to the outside coils, which then disperses to the air. does that on a grand scale change anything, so minute it doesn't matter, or does it not matter because its all in the closed system of Earth?",
"I'd like to point out that the source of your power depends on where you live. Here in the pacific NW almost all my power comes from renewables and I pay slightly more for 100% renewables. \n\nSo my AC costs damn near zero",
"It's cheaper to use A/C in the south than it is to heat your home in the north. Turns out, fighting 100 degrees outdoors to make your house 75 uses less energy than it does to fight 10 degrees outdoors to make your house 68. The mass migration of Americans to the south has been a net positive in terms of energy use for home temperature modulation. People just love to hate on A/C because it is a fairly new technology.\n\nI have seen many environmentally minded people saying that people shouldn't live in AZ or TX or that people should sweat out the heat, but no one would ever suggest that people in Boston or NYC should just wear long Johns and buy a winter-weather sleeping bag in order to get through the winter.\n\n_URL_0_\n",
"Buildings use about 39% of the US energy consumption, and of that 32-39% is HVAC (Heating, Ventilation and Air Conditioning).\n\n_URL_0_\n\nSo it's considerable. However, since air conditioning uses the heat-pump process to move heat from colder spaces to warmer spaces, it only takes a small fraction of the total energy moved to actually move that energy. In watts, it may only take about 30 watts to move 100 watts worth of energy. \n\n So while AC uses a lot of total energy in the scheme of things, it's really rather efficient when compared to combustion heating or electric resistance heating, where at least 100 watts of primary energy use would be necessary to get 100 watts of benefit. And compared to, say automobile transport, where approximately 4% of the energy burned in fuel is used to actually move the driver, it's phenomenally efficient.\n\nIn primarily heating-dominated areas, more and more heat pumps are being used to provide heat as well (or instead of) cooling for comfort or domestic water services. This offsets the less efficient gas or electric heat we currently use and overall decreases the footprint of buildings on the energy use of the world.",
"So I know this isn't a proper peer reviewed source, but this question was actually posed recently in the New York Times. I thought their article on it was pretty interesting. Like you, I thought that air conditioning/refrigerant wouldn't make a big impact on the environment relative to other areas, but it seems I was wrong.\n\n_URL_0_",
"I guess this is a good thread to ask the following as I've often wondered it.\n\nWhen the AC units we use in the country I live in are set to cool, the outside unit blows out pretty warm air. Aside from the heating effects of the greenhouse gases produced from electricity used, could the combined effect of millions and millions of individual AC units blowing warm air out into the world effect outside temperatures at all, even if only slightly? I'm thinking mostly temperatures in very densely populated cities like can be found in parts of Asia where you could have millions of units in a relatively small area.",
"Much of this discussion is about the Maths and statistics. Very little about the physics of how building heating and cooling is actually accomplished. Check [this video out](_URL_0_) - it's a nice, simple explanation about how heating/cooling works - and gives some hints as to the strategies involved with planning a heating and cooling system.",
"Air Conditioner Service Tech here: the biggest impact air conditioners have on the environment is the constant releasing of hydrocarbons into the atmosphere. Until just recently the refrigerant only used in ac units was R-22. R-22 contains chlorine and methane and what makes it harmful is the fact that all ac units leak or will develop a leak at some point. 99% of the time this leak is found in the coil which makes the leak unfixable. R-22 used to be cheap (around $20-30 a pound) so people just kept refilling there ac units until it just leaked out within a short period of time (like a month). \n\nThe tonnage of the unit will determine how many pounds of freon the coil and line set will hold but in my area (St. Louis Mo) the average tonnage is 2-2.5 ton. These hold around 4-6 pounds of freon. \n\nNow a common problem people have as there freon leaks out is there unit will freeze up. This is typically the first time the homeowner will notice something is wrong. When this occurs you can almost bet money on it that it will be 2 pounds low to the ounce. Every time. So imagine this on a massive scale in the US. Every home has a leaking or will be leaking AC unit. \n\nThis is a huge problem when you consider the time frame this has happened between. The 1950's to now. The EPA recently within the last 20 years decided to phase out R-22 by 2020. They have many new freons that do not contain hydrocarbons such as R-410a which is the new standard freon. But i am sure it is still somehow harmful to the environment as well, thus repeating the cycle over and over again.",
"Other than electrical usage, it's becoming less of an issue, but refrigerants that leak or are released into the atmosphere have ozone depleting potential. Old refrigerants like R-22 were having a significant impact and were phased out of production due to this. Many modern refrigerats still have significant global warming potential like R-410A. Thankfully the HVAC industry and the EPA have been keen on utilizing and replacing refrigerants that have minimal ozone depleting potential and global warming potential. "
]
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[] |
[] |
[
[],
[
"http://www.drawdown.org/solutions-summary-by-rank"
],
[],
[
"https://www.eia.gov/tools/faqs/faq.php?id=96&t=3",
"www.eia.gov"
],
[
"https://permies.com/t/9580/a/3102/Solarchimney.jpg"
],
[
"http://www.drawdown.org/solutions-summary-by-rank"
],
[],
[],
[],
[],
[
"http://www.brighthubengineering.com/hvac/965-chlorofluorocarbons-cfcs-refrigerants-that-cause-ozone-layer-depletion/",
"https://en.wikipedia.org/wiki/List_of_refrigerants"
],
[],
[],
[],
[],
[],
[],
[
"http://www.slate.com/articles/health_and_science/science/2012/08/air_conditioning_haters_it_s_not_as_bad_for_the_environment_as_heating_.html"
],
[
"https://www.c2es.org/technology/overview/buildings"
],
[
"https://www.nytimes.com/interactive/2017/07/13/climate/climate-change-make-a-difference-quiz.html"
],
[],
[
"https://www.youtube.com/watch?v=FyzRUNGyUDQ"
],
[],
[]
] |
|
2is2we
|
Independent Cities - How did it come about that St. Louis and Baltimore are the only two US cities not a part of their respective county?
|
St. Louis native here, and as much as the City/County split is a major topic of discussion around these parts (espcially lately), I don't know of anybody who knows how it actualy got that way. And I understand Baltimore is in a similar situation - is that a result of a similar historical factors or is it a whole different story?
|
AskHistorians
|
http://www.reddit.com/r/AskHistorians/comments/2is2we/independent_cities_how_did_it_come_about_that_st/
|
{
"a_id": [
"cl5arah"
],
"score": [
2
],
"text": [
"This does not directly answer your question about St. Louis, but Virginia also has cities being independent from the counties. It is he only state in the nation this way. This evolved from the colonial times and codified in the 1970's. Here is a link to good background summary:\n\n_URL_0_"
]
}
|
[] |
[] |
[
[
"http://www.encyclopediavirginia.org/Cities_of_Virginia#start_entry"
]
] |
|
2m0l9c
|
If Christianity came from the Middle East, why are there no Middle Eastern countries with a Christian majority?
|
AskHistorians
|
http://www.reddit.com/r/AskHistorians/comments/2m0l9c/if_christianity_came_from_the_middle_east_why_are/
|
{
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"text": [
"Christians in the Middle East largely converted to Islam over the centuries. However, there are still substantial Christian minorities in some Middle-Eastern countries.\n\nLebanon has a large Christian population, currently making up 40% of the population. Christians were, in fact, the majority religious group in Lebanon from its independence in 1943 to the Lebanese Civil War of 1975. Christianity is still the majority religion of the Lebanese diaspora.\n\nIn terms of absolute numbers, Egypt and Syria have the most Christians of any Middle Eastern country, although in both countries they make up only around 10% of the population.",
"*Zealot* by Reza Aslan (the guy who became popular for that horrendous Fox interview a while back) goes pretty in depth on this topic, albeit for a different reason.\n\nOne of the major themes of the second half of the book is the disagreements of Paul (who focused heavily on evangelizing to Jews in the Greek Diaspora and the pagans in Rome) and James the brother of Jesus (who very heavily focused his preaching on Jerusalem and the Jews of Palestine). Aslan focuses on how Paul and James had radically different interpretations on Jesus's teachings, particularly on who he was preaching for. Paul interpreted his teachings as tearing down the walls between Jews and Gentiles, hence the focus on the Greek Jews and, later, the people of Rome. James believed Jesus was a Jew preaching for his fellow Palistinian Jews and as a result took a very local view on the matter.\n\nThis starts to touch on your question with the sack of Jerusalem in 70 AD. As the Palistinian Jews were slaughtered or driven from their homes, James' congregants of the Middle Eastern church went with them. He viewed his church as a subset of Judaism, and when the Jewish population of the region dwindled, so did the Christian population.\n\nPaul's version of the church, however, flourished thanks to his letters to far-away congregations and eagerness to preach to non-Jews, folks who weren't uprooted from their homes and forbidden to practice their religion. Aslan especially focuses on the fact that most scholars believe the gospels were written several years after the sack of Jerusalem, and posits that they were colored in a way that would make Christianity more palatable to the Romans of Europe. He calls out how the gospels make Pontius Pilate look like a magnanimous and just man whose hands are tied because of the common rabble, while most Roman accounts of his rule in Palestine color him as a bloodthirsty tyrant who wouldn't think twice before executing a Jewish peasant. Aslan says the authors of the gospels realized their most fertile flocks were in Rome, and wanted to focus on bringing them into the fold.\n\nAll in all, it really is a fascinating book and very much worth all the attention it got. If it's a part of history you're interested in, I can't recommend it enough.",
"Well, there are, Armenia, Georgia, Cyprus, and Lebanon (sort of, about a 50-50 split). Even then, Armenia used to be about 80% muslim until the russians colonized the area with Armenians, Lebanon had a similar thing happen with the french colonizing the area with chrisitans, and georgia and cyprus spent most of islamic history under christian control, but still retained significant muslim minorities none-the-less. However, the reason why Christianity is no longer widespread is basically Islam and it's incentives towards conversion. You had a lot of extra taxes and while you were allowed to worship freely, it was often a pragmatic choice to simply convert over to islam. When you are dealing with over 1000 years of Islamic history and dominance, you will simply see one person take that choice out of one of the 50 or so generations of people and it simply stick because you could be executed for converting away. One thing I disagree with the rest of the thread on is how long it took however. To get about 50 percent of the population to convert, it took about 400 years, with a standard deviation of about 200 years if fully control by a moderate islamic government without colonization efforts. I am basing this off of what happened with the balkans, as [this is](_URL_0_) about 400 years of turkish control of the balkans, along with what happened with other regions, but that is only a back of the envelope type calculation. "
]
}
|
[] |
[] |
[
[],
[],
[
"http://i.imgur.com/OcaUOFz.gif"
]
] |
||
2xtgp9
|
why aren't all humans dark skinned?
|
I can't think of a single evolutionary benefit to having pale skin. Hiding in the nude in snow? Jokes aside, even slightly increased sun-resistance from having darker skin seems like a huge advantage, even in northern climates. Was it just from a lack of actual impact?
Edit: Wow, who downvotes ELi5? lol
|
explainlikeimfive
|
http://www.reddit.com/r/explainlikeimfive/comments/2xtgp9/eli5_why_arent_all_humans_dark_skinned/
|
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"text": [
"Vitamin D.\n\nThe further north you go, the less sun you get year-round. UV-rays from sunlight are used in the skin to metabolise Vitamin D, an essential vitamin. Less melanin in the skin (the stuff that makes your skin dark) means less UV blocked and more Vitamin D and better bone growth.",
"Lighter skin absorbs more vitamin D from the sun in climates where there is less sunlight for a lot of the year (like northern climates) ",
"Lighter skin makes it easier for your body to use sunlight to produce vitamin D, which is an advantage in northern climates with less sunlight. There's a balance between blocking enough UV to provide protection while letting enough through to produce enough vitamin D.",
"Vitamin D is pretty much the answer. Skin color is basically a balancing act of getting enough sun exposure to create vitamin D, but not enough to get skin cancer. So in Northern climates with less sun, you need lighter skin to absorb it. In equatorial climates, you need more sun protection, so dark skin."
]
}
|
[] |
[] |
[
[],
[],
[],
[]
] |
|
o42ay
|
Is there a scientific reason why we assume the foetal position when we are in pain?
|
It seems almost instinctive that everyone curled up when they're in pain.
Is our mind hard-wired to do this? This question occurred to me when I came close to fracturing my wrist today.
|
askscience
|
http://www.reddit.com/r/askscience/comments/o42ay/is_there_a_scientific_reason_why_we_assume_the/
|
{
"a_id": [
"c3eccdc"
],
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"text": [
"bodily instinct will be to protect itself and given that all our vital organs are in our torso shielding them with our un-vital arms and legs is just instinct so any horrible pain humans usually resort to instinct.\n\nBut its different for some people because everyones pain threshold is different so what may be horrible pain for someone may be bearable by someone else"
]
}
|
[] |
[] |
[
[]
] |
|
1be2ux
|
if doma gets overthrown in the scotus will same sex marriage be legal everywhere in the us? or will each state have to pass it individually still?
|
I thought DOMA only allowed states with no SSM laws to not recognizing licenses given in other states. So if DOMA was repealed would gay marriage be legal across the county or would it still be only is some states, yet transferable to any?
|
explainlikeimfive
|
http://www.reddit.com/r/explainlikeimfive/comments/1be2ux/eli5_if_doma_gets_overthrown_in_the_scotus_will/
|
{
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"c9611mb"
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"text": [
"DOMA does two main things:\n\n1. Makes it law so that if one state legalizes same sex marriages, all states do not have to recognize it.\n\n2. Denies federal marriage benefits to same sex couples, even in states where they are legally married. This is Section 3 of the law.\n\nThe part being talked about right now at SCOTUS is section 3. The rest or the law isn't bring contested right now, and though I believe they COULD strike down the whole act if they wanted to, it in very unlikely.\n\nSection 3 is really all that the federal government has to do with recognizing same sex marriage, legal same sex marriage comes at the state level.\n\nState-level SSM *is* being talked about, in the Prop 8 case (Hollingsworth v Perry), but SCOTUS watchers say the court is extremely unlikely to issue a ruling legalizing same-sex marriage everywhere."
]
}
|
[] |
[] |
[
[]
] |
|
b3xv81
|
why isn't government used software open source?
|
[deleted]
|
explainlikeimfive
|
https://www.reddit.com/r/explainlikeimfive/comments/b3xv81/eli5_why_isnt_government_used_software_open_source/
|
{
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"text": [
"They probably bought a license and don’t own it. The government uses Microsoft office, but they buy volume licenses, Microsoft still owns all rights so it can’t be open source. ",
"Because there is no legal requirement to limit itself to that kind of approach.\n\nElections are very regulated, to prevent fraud. So unless you are going to explicitly ban one kind of exclusively use another kind, it will not go anywhere.\n\nThe only way to change it is to get involved and improve it.",
"I'm a government person involved in purchasing SW. And the short answer is they do.\n\nThe long answer is much of the SW they need must be custom and the government is not really interested in paying someone to write SW and then hiring other people to fix it when it breaks. They've tried that, it never ends well. On top of that, support is a very much something they need, if it breaks they want a number to call. The last thing is price, governments have budgets, they need to make all the stuff cheap, if open source can do it, all the better.\n\nThat results in a few things, if open source can be used, they'll always end up paying someone else to be the support for the stuff they use, they'll never use debian directly, but they are more than happy to sign up for a RHEL contract and let them deal with it, this has the effect that it isn't always the cheapest option because free software is unsupported and that's a nonstarter. Another issue is the cost of investing into development and it's predictability, spending $10 million to develop a system, and then finding it doesn't work, dropping another $5mil fixing it, and then 5 years later you need to pay $5mil for it again? How do they forecast that? What happens when it's over budget? What is the contractor decides to refuse to work for a reasonable fee? Training a new contractor is expensive and takes time. No, that doesn't work. It is FAR easier to just sign a contract with a vendor who says it's $500/machine/yr, and it's guaranteed to always be updated, and they'll always fix bugs within a year at no extra cost. The contractor selling that package is going to be very against open source, because their income is dependent on keeping that contract. They will spend whatever they have to to avoid open source, and avoid contaminating their code with things like GPL that could allow their competitors to take it. It's irrelevant that open source is cheaper, they are the ones getting paid. It has the side effect that it's unlikely to see open source voting SW because the government already has a signed contract for existing SW."
]
}
|
[] |
[] |
[
[],
[],
[]
] |
|
2nne4z
|
Is there a chance of siblings not sharing any genetic material?
|
For example: A boy has one X chromosome from his mother and the Y from his father, while his sister has the other X chromosome from her mother and the X from her father?
EDIT: Thanks for the replies! I feel strangely disappointed that the chance is so small :(
|
askscience
|
http://www.reddit.com/r/askscience/comments/2nne4z/is_there_a_chance_of_siblings_not_sharing_any/
|
{
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"text": [
"While it is formally possible, the probability of sharing NO genetic material is vanishingly small (ie, essentially zero). A fairly simple straightforward explanation that might help give a sense to the numbers can be found here: _URL_0_",
"The chance is so small it's basically zero.\n\nYou don't get a whole single chromosome from each parent, for example you getting copy 1 of chromosome 5, and your sister getting copy 2. Chromosomes [randomly swap pieces](_URL_0_) between each other during sex cell creation. So your chances of being \"unique\" are many times greater than 2^23 (which is already a fairly large number)."
]
}
|
[] |
[] |
[
[
"http://genetics.thetech.org/ask-a-geneticist/why-siblings-share-around-fifty-percent-their-dna"
],
[
"http://en.wikipedia.org/wiki/Homologous_recombination"
]
] |
|
1405jj
|
What capabilities would the now abandoned Super Colliding Superconducter have had compared to the LHC? Are there any questions it could have answered that the LHC cannot?
|
askscience
|
http://www.reddit.com/r/askscience/comments/1405jj/what_capabilities_would_the_now_abandoned_super/
|
{
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"text": [
"I would suggest you to read [this](_URL_0_) for starters.\n\nAlso, a minor difference but it got me confused for a second, it's called Superconducting Super Collider, or SSC.",
"The SSC was expected to run up to 20 TeV (TeV is a measurement of energy, Tera-electron Volts) while the LHC is only going to hit 7 TeV in 2014. Using the standard model they can predict what range of energy certain particles will have, for instance before the LHC fired up they figured the higgs boson had between 115–130 GeV (Giga-electron volts). The couldn't find the higgs boson with the tevatron (the biggest collider before the LHC) because it couldn't produce enough energy to create the boson. The SSC would produce almost triple the energy of the LHC, allowing scientists to examine particles that they don't even know exist.\n\nEDIT: To add to this, I think supersymmetry predicts that there are particles with orders of magnitude more energy for each subatomic particle that exists. To prove this they would need a lot of energy, possibly more than the LHC can produce in order to create these particles. "
]
}
|
[] |
[] |
[
[
"http://blogs.scientificamerican.com/talking-back/2012/07/06/higgsteria-we-didnt-need-no-super-collider/"
],
[]
] |
||
14fwbw
|
Today marks the anniversary of the last time the United States declared war - WWII. What is the difference between a declaration of war and a military engagement?
|
AskHistorians
|
http://www.reddit.com/r/AskHistorians/comments/14fwbw/today_marks_the_anniversary_of_the_last_time_the/
|
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"When congress passes legislation that uses the term \"Declaration of War\" in the title, it's often referred as the formal Declaration of War. U.S. congress has not **formally** declared war since WWII. The only difference between formal declaration and authorization of war by Congress is using the \"Declaration of War\" in the title. Vietnam War, Gulf War, 2001 war in Afghanistan and 2003 Iraq War were all authorized by Congress without using the term \"Declaration of War\". There was nothing fundamentally different. Constitution gives Congress the power to declare War but it does not require using any formalisms. \n\nSometimes U.S has been involved in military engagement that was authorized by UN Security Council Resolution and funded by Congress. President may interpret the law and assume that there is no need for authorization from Congress to carry out the United Nations resolutions. \n\nSee also [The War Powers Resolution of 1973](_URL_0_).",
"You're off by one day: _URL_0_\n",
"Actually World War 2 was declared by the Americans on December 8th. A few days later Germany declared war on the US and the Americans declared war on them too.",
"A declaration of war is needed when your opponent is an industrialized power because it has significant practical ramifications for things like shipping, ports of call, air traffic routes, business contracts, legal status of foreign nationals, banking and financial systems, communications networks, that sort of thing. This is obviously less of an issue when you're involved in a conflict with a less-developed power, or a group that doesn't actually represent a sovereign nation.\n\nThere are lots of legal issues involved as well. If you're Nation A and you have an alliance or a certain type of treaty in place with Nation B, then when you declare war on Nation C, Nation B might be required to declare it as well. A military engagement without a formal declaration doesn't normally trigger those types of requirements.",
"Strictly speaking, this is not the anniversary of the last time we declared war. At most, it's (the day before) the anniversary of the last time we entered into a war via a declaration. The last time the United States declared war was [June 5th, 1942](_URL_0_) against the European Axis nations that weren't Germany or Italy."
]
}
|
[] |
[] |
[
[
"http://www.loc.gov/law/help/war-powers.php"
],
[
"http://en.wikipedia.org/wiki/United_States_declaration_of_war_upon_Japan"
],
[],
[],
[
"http://en.wikipedia.org/wiki/Declaration_of_war_by_the_United_States"
]
] |
||
4dczev
|
Are there any issues in which the historical record and archaeological evidence strongly disagree with each other?
|
AskHistorians
|
https://www.reddit.com/r/AskHistorians/comments/4dczev/are_there_any_issues_in_which_the_historical/
|
{
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"text": [
"The legend of the Dorian Invasion would be a good example of this. The Ancient Greek literary tradition held that Spartan rule over the region of Lakedaimon was established during this Invasion (also called the Return of the Herakleidai), in which the Dorians (to whom the Spartans belonged) descended into the Peloponnese and drove out the local ruling classes. This was supposed to have happened at some point in the distant past, possibly in the 10th century BC. It gave the various Dorian peoples of the Peloponnese an epic origin story, and explained why local dialects had disappeared in favour of Dorian Greek by the end of the Greek Dark Age.\n\nIn theory, it seems plausible enough that this legend would go back to an actual historical event. Mass migrations frequently lead to the replacement of one ruling elite with another, and incursions from the Balkans into mainland Greece were certainly not uncommon in later times.\n\nThe only problem is that there is not a shred of archaeological evidence to back it up. There is no sign of violent conflict, no evidence that the material or civic culture of Lakedaimon changed dramatically during this period, and nothing to suggest that its culture became different from that of other Greek areas.\n\nFor this reason, scholars now assume that the idea of a Dorian Invasion was an explanation invented by the Greeks in hindsight, rather than a surviving tradition about a real historical event."
]
}
|
[] |
[] |
[
[]
] |
||
svyct
|
If heat is the jiggling of particles which can't exceed the speed of light, does this mean there's an "Absolute Hot" similar to absolute zero?
|
askscience
|
http://www.reddit.com/r/askscience/comments/svyct/if_heat_is_the_jiggling_of_particles_which_cant/
|
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"\"There is no agreed-upon value, among physicists, for a maximum possible temperature. Under our current best-guess of a complete theory of physics, the maximum possible temperature is the Planck temperature, or 1.41679 x 10^32 Kelvins\" - [Source](_URL_0_).\n\nThat's 141,679,000,000,000,000,000,000,000,000,000 K.",
"Wikipedia actually has a page called \"[Absolute Hot](_URL_0_)\", which is quite good.",
"Absolutely not.\n\nFirst of all, even if temperature were just kinetic energy, kinetic energy isn't limited by light speed. As velocity increases to light speed, the corresponding kinetic energy increases without bound, for the same reasons as time dilation and length contraction.\nEDIT: (See [adamsolomon's reply](_URL_1_) for a more thorough discussion.)\n\nSecondly, temperature is not kinetic energy. Temperature is a measure of which way energy will flow between two systems, measured as the inverse of \"[coolness](_URL_2_)\", which is the derivative of the entropy of a system with respect to its energy. In many systems this can asymptotically approach zero, which is a temperature of infinity. [However, some systems can go below zero, and even approach minus infinity](_URL_0_). In fact, the hottest possible temperature is also 0, but approached from the negative, rather than positive side.",
"Also, consider the fact that temperature is often taken to be a statistical measure that is only really well defined at equilibrium (or at a steady state). It's hard to really imagine that you'd be able to meet those requirements as you continue to pump energy into the system.",
"Even ignoring all the other (non-trivial) subtleties, the important take-home point is that temperature of a substance is (basically) the average kinetic energy of its particles, and even though speed has a maximum, kinetic energy doesn't. This is because the usual relationship between velocity and kinetic energy (1/2 mv^2 ) is only an approximation that holds at low velocities; in the high-speed case, kinetic energy gets arbitrarily high as speeds approach the speed of light.\n\nI've ignored lots of subtleties, as I said, in terms of which reference frame we're talking about, how you define energy, how temperature might behave in (speculative) ultra high energy physics, and so on, but I think this is the big conceptual point in answering your question. A maximum speed doesn't equate to a maximum kinetic energy, or temperature.",
"Late to the party here, so will probably remain invisible, but temperature doesn't really mean what you think it means -- unless you already properly [grok](_URL_1_) [wnoise's nice answer](_URL_2_).\n\nMany folks, including DarthSatoris, tend to assume that temperature is a measure of particle energy. But it really isn't in the general case, only in some specific cases that happen to be handy a lot of the time. \n\nHere's some [copypasta](_URL_0_) of a post I made 2 years ago answering basically the same question, which is something of a FAQ. It is worth following the link because that discussion thread contains many insightful posts.\n\n~~___________________________________________________________________________~~\n\n\nIn short: No.\n\nIn slightly longer: Temperature isn't a fundamental physical quantity, it is a ratio (well, a derivative) -- and it's possible to engineer the denominator to be positive (the usual case), negative (unusual) or zero (highly unusual but possible).\n\nIn much longer: a measure of the marginal relationship between energy and entropy: T=dE/dS. Energy is, well, energy of the system whose temperature you are measuring. Entropy, loosely speaking, is a measure of the number of bits required to store the complete state information about the system -- it is the logarithm of the \"state function\" (the number of quantum-mechanical states that a system may have and still fit its macroscopic description).\n\nFor collections of free-moving particles, like gases, the relationship between E and S is quadratic, so dE/dS is linear in E over a wide range of energies -- that's why Boltzmann's Constant (1.38e-23 J/K, or alternatively 0.08206 liter atm / K mole) is, er, constant.\nFor other types of systems, E and S aren't related so simply.\n\nFor example, in many laser systems, dE/dS is actually negative: raising more electrons into the excited state (pumping the laser) can actually reduce entropy: if more than half the suitable electrons in the system are excited into their higher state, then raising another electron into the excited energy level actually decreases the number of states available to the system as a whole. In systems like that, the line excitation temperature is actually negative(!).\n\nIt is also possible to construct systems where the entropy is constant against changes in system energy -- in that case, dS/dE is zero and dE/dS (the temperature) is infinite.",
"As far as I know, there are at least two ways of measuring temperature.\n\nThe way that I learned (and still recall) is the change in internal energy with respect to the entropy of a system. As the vibrational energy levels of the particles in a system become more full, entropy will increase, until addition of energy actually decreases the entropy of a system.\n\nThis causes a temperature of 0 at the point of highest entropy, and upon adding more energy to this system, the temperature will become negative (but still mind blowingly hot).\n\n",
"The physics of maximum hotness are much less clear-cut than the physics of maximum coldness.\n\n > Current cosmological models postulate that the highest possible temperature is the Planck temperature, which has the value 1.416785(71)×1032 kelvin. The Planck temperature is assumed to be the highest temperature in conventional physics because conventional physics breaks down at that temperature. Above ~1032^32 K, particle energies become so large that there is no existing scientific theory for the behavior of matter at these energies. Gravitational forces between them would become as strong as other fundamental forces, requiring a hypothetical theory of everything for description. see [Absolute hot](_URL_0_)\n\nTo jeer slightly off-Broadway, it's profound to think that both the hottest and coldest points in the Universe may lie on planet Earth (the LHC and Cambridge MIT, respectively, when running).",
"relevant [straight dope](_URL_0_) \nApparently, at 10^32K every particle becomes so massive that each one becomes its own black hole and space time collapses, kind of like crossing the streams.",
"Quoting the book \"What Einstein Told His Barber\" By Robert L. Wolke, \"Theoretical considerations peg this temperature at around 140,000,000,000,000,000,000,000,000,000,000 degrees- Fahrenheit or Celsius, take your pick\" (92). \nI have no expertise on the subject and all matter in this comment was taken from the book. ",
"As someone noted, temperature is simply defined by 1/T=ds/dE where s is entropy and E is energy. by this, you can think of 1/T as how much a system \"wants\" energy. a system with high T \"wants\" energy less than a system with low T, thus if they are in thermal contact, the system with high T will give energy to the system with low T.\n\n\nby this, something is \"hotter\" than something else if it is willing to give energy to it if they are in thermal contact. note that this definition says nothing about the speed of the particles (though the two are often highly correlated).\n\nas it turns out, there can exist systems that do not \"want\" energy at all. by our definition above, these systems have a 1/T=0, thus they have infinite temperature.\n\neven infinite temperature, however, is not the \"hottest\" temperature, as many systems actually have negative \"want\" for energy. these systems, then, have negative temperature, and will give energy to any system with positive (or infinite) temperature, and are therefore even hotter.\n\njust like as we make things colder, we can approach 0K from the positive side, as we make things hotter, we approach -0k from the negative side.\n\nhere is a good wikipedia article on negative temperatures that mentions infinite temperature:\n\n_URL_0_"
]
}
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[] |
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[
[
"http://www.wisegeek.com/what-is-the-highest-possible-temperature.htm"
],
[
"https://en.wikipedia.org/wiki/Absolute_hot"
],
[
"http://en.wikipedia.org/wiki/Negative_temperature",
"http://www.reddit.com/r/askscience/comments/svyct/if_heat_is_the_jiggling_of_particles_which_cant/c4hge6n",
"http://en.wikipedia.org/wiki/Thermodynamic_beta"
],
[],
[],
[
"http://www.reddit.com/r/science/comments/auwpu/i_have_a_science_question_is_there_an_antithesis/",
"http://en.wikipedia.org/wiki/grok",
"http://www.reddit.com/r/askscience/comments/svyct/if_heat_is_the_jiggling_of_particles_which_cant/c4hg15o"
],
[],
[
"http://en.wikipedia.org/wiki/Absolute_hot"
],
[
"http://www.straightdope.com/columns/read/807/what-is-the-opposite-of-absolute-zero"
],
[],
[
"http://en.wikipedia.org/wiki/Negative_temperature"
]
] |
||
158l02
|
Why is that an ARM based processor and an x86 based processor cannot be compared clock for clock.
|
For example, a 1.7ghz cpu might have better performance using x86 architecture vs A15.
|
askscience
|
http://www.reddit.com/r/askscience/comments/158l02/why_is_that_an_arm_based_processor_and_an_x86/
|
{
"a_id": [
"c7k7k5r",
"c7kcyed",
"c7ke7io",
"c7kfaru"
],
"score": [
7,
2,
3,
2
],
"text": [
"You can't compare even different core architectures using the same instruction set clock for clock. \n\nGenerally ARM instruction set is more RISC-like than x86. On average, each instruction does little less than x86 instruction. Binary sizes for ARM are little bigger than for x86 (10-15% bigger). \n\nMany other different parameters between the processors change over time. \nCurrently ARM processors are superscalar, in-order design. It can execute multiple instructions per clock cycle but only on order. Most x86 designs don't have that restriction. Intel Atom series however does. Currently ARM has much better integer performance than Intel Atom, but much worse floating point performance. \n\n\n",
"* Instruction length is different. ARM fixes instruction length to 32bits... x86 has some really short instructions. \n\n* x86 is a disgusting hack... the whole point of RISC is to reduce the instruction set to the basic instructions. This means x86 has a lot more specialized instructions. So one x86 instruction might take a boat load of ARM instructions... (this isn't necessarily great... it means x86 is loaded with shit that no one uses... that's bad for power)",
"If the microarchitecture is different you can't compare clock-for-clock. I am absolutely not a car person, but it's like comparing the speed of a solar vehicle and a truck when you're only accounting for horsepower.\n\nClock frequencies have been useful in the past when microarchitectures were similar, but benchmarks (flawed though they are) are really the best you can use to compare different types of processors. For some basic differences of just a few ARM architectures (expressed in a dhrystone (synthetic benchmark) per mhz benchmark) scroll down to the end of [this page](_URL_0_). Comparing ARM cores alone is complex, let alone bringing in x86 cores into the mix. The best you can do is comparing real world benchmarks.",
"Because it's also about instructions per clock. And that metric changes depending on the instruction (or equivalent instructions) in question, how they're ordered, and what potential branches are coming up in the code under examination."
]
}
|
[] |
[] |
[
[],
[],
[
"http://www.anandtech.com/show/4991/arms-cortex-a7-bringing-cheaper-dualcore-more-power-efficient-highend-devices"
],
[]
] |
|
uke9g
|
My buddy's dad found this rock on their farm. Apparently a meteorite may have hit the region, could this rock have been affected by that collision?
|
_URL_0_ This was found near the Flint River in middle Georgia. Some scientists are starting to believe a rather big meteorite hit this area causing a pretty big topography change for the area. Apparently the river should not run the way it does through the topography it goes through unless a change happened after the river already was going through the area. In person this rock is looks awesome, especially if you put some water on it.
EDIT: Found [this](_URL_1_), which discusses this possible meteorite crash.
|
askscience
|
http://www.reddit.com/r/askscience/comments/uke9g/my_buddys_dad_found_this_rock_on_their_farm/
|
{
"a_id": [
"c4w7rsk",
"c4w83mj"
],
"score": [
3,
3
],
"text": [
"I haven't found a lot of peer-reviewed journal articles about the impact, but what I've found seems to indicate it happened 83 million years ago. At that time, that part of Alabama/Georgia was under a shallow sea. I'm rather skeptical that a rock that large would be found in overlying sediments, especially a farm. However, it could be.\n\nI'm not a geologist, but the rock is very interesting. It's hard to tell, but that almost looks like a fossil leaf or something, but if the rock is igneous, then there would be, of course, some other explanation.\n\nYou might want to dig up a reliable peer-reviewed citation as to the bolide impact before others answer. ",
"First off, it's probably not a meteorite. [Hullabazhu linked to a good site](_URL_0_) that describes what a meteorite looks like.\n\nThe only rocks that are created by meteor impacts that I know of are [Tektites](_URL_2_). However, tektites usually look very smooth due to being melted by the meteor impact. \n\nMy guess would be that the colors are caused by a pyrite deposit. Pyrite is fairly common in almost any part of the Earth. Although it's quite cool to see it when it forms rainbow iridescent colors. [Here's some pics I found of pyrite deposits in a few different types of rock.](_URL_1_) If there's a significant amount of pyrite within the rock, a powerful magnet should feel attracted to it. Although the colors seem pretty faint, so it might just be a trace deposit. "
]
}
|
[] |
[
"http://i.imgur.com/kwZDp.jpg",
"http://www.flintriverastronomy.org/Articles/TheCoveArticle.pdf"
] |
[
[],
[
"http://www.reddit.com/r/askscience/comments/uke9g/my_buddys_dad_found_this_rock_on_their_farm/c4w7fto",
"http://imgur.com/a/qqsKC",
"http://en.wikipedia.org/wiki/Tektite"
]
] |
|
337avz
|
Are Cloudless Tornadoes possible?
|
Since Tornadoes are essentially two air masses of different temperatures, and there can be clear, no cloud, air masses, can they collide to make an "invisible" Tornado?
|
askscience
|
http://www.reddit.com/r/askscience/comments/337avz/are_cloudless_tornadoes_possible/
|
{
"a_id": [
"cqivc17",
"cqj5awu"
],
"score": [
5,
6
],
"text": [
"A tornado is only visible because of the debris it throws around. The air can tornado without picking anything up. If the tornado formed in an area with little to no loose ground cover, like a flat rock desert, it might be hard to see.",
"I'm assuming you mean actual tornados since you can of course have phenomenon like dust devils which can be invisible, but these don't form the same way as tornados. \n\nThe process of creating a tornado is much more complex than just two air masses colliding. The conditions that are required for a tornado to form, result in thunderstorms. For example, you need strong updrafts and downdrafts for a tornado to form. Strong updrafts/downdrafts only exist within thunderstorms. You can have part of the tornado be invisible, near the ground. However this is usually only for a short period when the tornado first hits the ground, before the condensation funnel reached the ground. "
]
}
|
[] |
[] |
[
[],
[]
] |
|
a0j4zn
|
how does a country first react if they are being invaded by another country?
|
explainlikeimfive
|
https://www.reddit.com/r/explainlikeimfive/comments/a0j4zn/eli5_how_does_a_country_first_react_if_they_are/
|
{
"a_id": [
"eahzyhc",
"eai0j8z"
],
"score": [
4,
3
],
"text": [
"Normally there is some form of advanced warning, in some cases a declaration of war in others intelligence gathering indicating a build up of forces on the border area. The general first action is a mobilisation of the army, so all on leave etc. army forces report to designated areas to arm and deploy. It then depends upon the nature of the attack and the defensive measures used sometimes the border zone will be strongly defended other times they will allow territory to be taken in order to enable full mobilisation of the armed forces.",
"It depends a on the specific circumstances, but in most cases invasions don’t come suddenly out of the blue. The country’s military will have mobilised, will have taken up defensive positions. Meanwhile, the government will be trying to press its diplomatic case with other countries, the UN, etc.. Sometimes the other side will have issued some kind of ultimatum so everyone knows what’s coming. \n\nAlso, there’s often a gap between the outbreak of war and any actual *invasion*. You could have border skirmishes, raids, air attacks, even a full-blown naval war before any invasion (if it happens at all). \n\nThe important thing is to see an invasion as part of a process of escalation – it rarely comes out of nothing."
]
}
|
[] |
[] |
[
[],
[]
] |
||
27xvzc
|
Is friction affected by surface area? For instance if I bought bigger tires for my car would I stop faster? what is the equation for this?
|
Is friction affected by surface area? For instance if I bought bigger tires for my car would I stop faster? what is the equation for this?
|
askscience
|
http://www.reddit.com/r/askscience/comments/27xvzc/is_friction_affected_by_surface_area_for_instance/
|
{
"a_id": [
"ci5i63v"
],
"score": [
3
],
"text": [
"Contact area does **not** affect frictional force. \n\nYou might be surprised (I was!), but think about a 1kg 2x1x1cm block on a ramp. Put the brick down sideways, and the surface area is 2cm^2. That 1kg is being distributed over that whole 2cm^2 with a force of 500 grams per cm^2.\n\nNow stick that block on the 1x1 side. Now the surface area is 1, but the mass is still the same. The same 1kg is being distributed over 1 cm^2, so the force is twice as big per unit area. \n\nAlright, cool. If we keep the mass of the car the same, there's no effect. But if the wider tires make the car more massive (and I suspect they do), there would be a very small effect proportional to the added mass of the wider tires. \n\nI suspect this is not what you're getting at, however. The answer to your question is, broadly, no. \n\nAdditionally, the equation generally used is Force of friction = coefficient of friction * normal force (essentially the weight of the object). \n\nSources: Amonton's Laws via Wikipedia. \n\nEdited to add follow-up question for anyone with more physics knowledge than I: Why do drag racers have wider tires?"
]
}
|
[] |
[] |
[
[]
] |
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