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bibh8o
|
how does the 20 questions electronic game work?
|
It’s able to guess so many different things with the most basic question, how is it so consistent?
|
explainlikeimfive
|
https://www.reddit.com/r/explainlikeimfive/comments/bibh8o/eli5_how_does_the_20_questions_electronic_game/
|
{
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"text": [
"It's basically a \"binary search\". Let's look at guessing a number between 1 and 100.\n\nYou pick a number in the middle (50) and *that rules out half the questions*. If the number you want is higher or lower, you repeat this (25), and again (12) and again (6) and again (3) and again (2). You can mathematically show that you can always find the number in 7 or fewer guesses by following this. In fact, the number of things you can identify by a series of *N* yes/no questions is 2^*N*.\n\nFor *N* = 20, that gives you over a million possibilities. The number is *even bigger* if the question allows for multiple answers other than just yes/no.",
"\n\nFirst, come up with a bunch of yes/no questions that would be good for a 20 questions game.\n\nSecond, collect a bunch of objects, and answer some or most of these questions for each object.\n\nNow, you have a good database of objects and an associated list of the yes/no answers for each object. \n\nWhen it comes time to ask a question, have the computer look through the list and find a question that has roughly half of the objects with a yes and half with a no. When the player answers, your list of objects is now half as small. If some of your objects didn't have an answer for that question, keep those too. Now, look at your remaining objects, and repeat the process, always picking a question that splits the objects into about half yes and half no. After 20 questions, halving each time, you will have sorted through about 1,000,000 possible answers. The questions might not always seem to make sense, but to the computer, this is the most efficient way to find your item.\n\nAt this point you have a working system, but it takes a long time to get this data. If you are smart, you can make your game even better the longer it gets played \n\nNow, have a bunch of people play the game. LOTS of people. Keep track of their answers as you go. Put it on [A WEBSITE](_URL_0_) so you can get answers from thousands of people. If they have an object you couldn't guess, add it to the list, and save the answers you got, or update the answers you already have. If you get lucky and narrow the answer down before all 20 questions are used up, look at some of the other questions for that object you don't have answers for and ask those so you always get more data. This is why if you play the online version it might seem like it's on the right track and suddenly ask if your potato \"wears a cape\". It already knows the answer is \"potato\" ; it's just collecting more info about potatoes to make it even smarter. You could even ask the player if there is a particular question they should have asked and if so add that to the list of possible questions for next time. If people sometimes answer differently for the same question, keep track of the percent yes vs no and take that into account when asking your questions (i.e. If \"are potatoes healthy\" gets 50/50 yes or no, don't eliminate that answer right away if you ask that question. \n\nLast, grab your latest version of the database, put it in the toy, and done."
]
}
|
[] |
[] |
[
[],
[
"http://20q.net/"
]
] |
|
6a8r03
|
Why was the Avro Arrow destroyed?
|
I've heard varying stories on why Avro cancelled the CF-105 Arrow.
On one hand, the conspiracy is that large american defense contractors and aeronautical corporations told off the American government, who then intimidated Prime Minister Diefenbaker into axing the Arrow and Iroquois programs.
On the other, Avro was faltering at a management level, there were few potential buyers of the interceptor model, and the whole program was very expensive and dubious when compared to the development of the Convair F-106 Delta Dart, which had similar capabilities but was completed sooner.
|
AskHistorians
|
https://www.reddit.com/r/AskHistorians/comments/6a8r03/why_was_the_avro_arrow_destroyed/
|
{
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"During the late 50’s the threat perceived to radiate from the soviets was changing.\nIt is argued that the Canadian Government was operating in an information vacuum with regards to this threat.\n\nAs a reaction to the detonation of the Soviet Hydrogen Bomb in 1953 NORAD was under development, a system that should provide early warning for the US when Russian Bomber approached the Continent, and would coordinate the responsive measures. In order to push the warning line forward units would have to be stationed on Canadian soil. \n\nThis came into play around the same time a new government came into power in Canada, that of Diefenbaker. A discussion broke out whether or not the Norad agreement would mean that Canada was giving up it’s sovereignty, as Canadian units would fall under American control. In the end the Canadians perceived the Russians to be a greater thread and agreed to NORAD. \n\nCoincidental with the development of NORAD was the development of the Avro CF-105 Interceptor. Many people around Diefenbaker noted that he was not open to take advice on defence. Thus the government at first ignored some important views by not taking advice from a group of military advisors that upheld the view that the perceived Bomber Threat was quickly turning into an IBCM threat. \n\nThe main thought with regards to air power at the time was an offensive one: Namely that it was important to strike first. From WWII the notion survived that of a large bomber force only a small number of bombers would be shot down. In the case of these bombers carrying an nuclear load even a handful of survivers could have a devastating effect. To quote prof J.I. Jackson:\n\n“the real air defence is the thermonuclear retaliatory or counter force, supported by the radar warning system that will allow it to take off before it can be destroyed on the ground. The defensive interceptor and electronic weapons are no longer the teeth of the air defence system, but rather comprise a subsidiary arm of the warning net, and have the same purpose in this as civil defence and defence against missile bearing submarines in helping to dissipate the casualties of the attack.” (1)\n\nTo repudiate the claim that Canada was bullied into stopping the program. Recent declassification of documents (around 2011) shows that in fact the US was interested in absorbing the biggest part of the costs of procuring the CF-105 for both the RCAF and the RAF air defence squadrons. The tragedy is that this information never reached the Canadian decision makers. The US was not interested in the CF-105 for use in the USAF, mainly as a result of the F-108 that they had on the drawing board.\n\n“. While the confused decision-making structure, dislike of committees, and seeming mistrust of senior military leadership were inescapable features of Diefenbaker’s personality, there is evidence that he was failed by those entrusted with ensuring needed information was pushed forward. In this case, information that told of a potential US commitment to assist in the acquisition of larger numbers of CF-105s to meet NORAD requirements and answer an enduring threat to the continent did not reach Diefenbaker.” (2)\n\n\nThe CF-105 was cancelled on the prevailing thought that now existed with the Canadian decision makers: Namely that the bomber threat was waning, and that IBCM’s now were the main threat. This proved to be erroneous as the bombers of the USSR still were a threat, at least until the late 1960’s In addition the critical information on the US’s willingness to purchase a number of CF-105’s for the RCAF never reached Diefenbaker. Thus the decision was made based on economics: Do we buy aircraft to defend against a threat we think is waning, or do we participate in NORAD and stationing of the BOMARC missille system, which is cheaper than the number of CF-105’s we need? They decided for the latter. If Diefenbaker had the relevant information available to him it is quite likely that the decision would have been different. \n\n\n**Sources**\n\n(1) Brad W. Gladman, Continental Air Defence: Threat Perception and Response, (2012) p 14.\n_URL_1_\n\nIbid, p 37.\n\nNorad at 40, historical overview\n_URL_0_\n"
]
}
|
[] |
[] |
[
[
"https://fas.org/nuke/guide/usa/airdef/norad-overview.htm",
"http://cradpdf.drdc-rddc.gc.ca/PDFS/unc120/p536662_A1b.pdf"
]
] |
|
anirql
|
Has there been a time in Western culture when muscular men were not considered sexy/attractive?
|
The cultural standards by which a woman's weight and shape have determined her sexiness have changed dramatically over time in Western/European societies. For example large, curvy "rubenesque" women were deemed sexy for much of the 17th and 18th centuries whereas today, thinness is praised > curves.
I'm wondering if the (subjective) attractiveness of a man's physique has similarly fluctuated? In what ways?
|
AskHistorians
|
https://www.reddit.com/r/AskHistorians/comments/anirql/has_there_been_a_time_in_western_culture_when/
|
{
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"eftyfl9"
],
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"text": [
" > The cultural standards by which a woman's weight and shape have determined her sexiness have changed dramatically over time in Western/European societies. For example large, curvy \"rubenesque\" women were deemed sexy for much of the 17th and 18th centuries whereas today, thinness is praised > curves.\n\nYour premise is really a pretty bold claim and mostly seems like a simplistic misinterpretation of art, it has been addressed here many times, for example here _URL_0_ by u/chocolatepot , who also, if briefly, addresses male beauty. \n\nIn any case, one should really differentiate between various \"considerations\" of \"sexy/attractive\": \n\nIs a depiction meant to be idealistic or maybe just realistic, is it about some general expectations from the opposite sex, or rather *self*-image, or artistic ideas, or tastes of particular artists (what's their sex? sexual orientation? status?), or just detached symbolism, or idea(l)s of particular groups... All of those are related yet ultimately very different questions requiring their own kinds of sources. \n\nJust consider how you'd evaluate what modern bodybuilding vs regular fashion magazines vs pornography vs various movie genres vs what men/women expect vs what they fantasize about vs what they tend to end up with (don't) say about beauty ideals... "
]
}
|
[] |
[] |
[
[
"https://www.reddit.com/r/AskHistorians/comments/4e8c52/did_heavier_men_and_women_used_to_be_considered/"
]
] |
|
24og33
|
how is chewing bones good for dogs teeth, and can it benefit humans?
|
explainlikeimfive
|
http://www.reddit.com/r/explainlikeimfive/comments/24og33/eli5_how_is_chewing_bones_good_for_dogs_teeth_and/
|
{
"a_id": [
"ch94abg"
],
"score": [
5
],
"text": [
"Their teeth are specifically designed to crush softer bones like ribs and vertebrae unlike our teeth. When dogs eat lots of softer foods like commercial dog food their teeth can't get tartar build up on it just like our teeth; gnawing on bones will help scrape the build up off."
]
}
|
[] |
[] |
[
[]
] |
||
avisrz
|
how do audio recordings that are stored in binary code on devices get re-converted to the sound that comes out of my phone’s speakers?
|
explainlikeimfive
|
https://www.reddit.com/r/explainlikeimfive/comments/avisrz/eli5_how_do_audio_recordings_that_are_stored_in/
|
{
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"ehfgzqf"
],
"score": [
2
],
"text": [
"It is covered thanks to a device called a DAC (digital to analogue converter).\n\nWhen audio is traveling in a speaker wire, it is just an electrical impulse - it has a voltage and a frequency based on what the sound is. That voltage and frequency is then amplified (by an amplifier) and pushed to a speaker cone, which vibrates at that specific amplitude and frequency to make sound waves in the air.\n\nA DAC is able to take the bianary data and create impulses in the speaker wire at that specific voltage and frequency, which then travels down the wire."
]
}
|
[] |
[] |
[
[]
] |
||
14094l
|
[Meta] Book List Meta Thread
|
This might be the best place to put suggestions about the list, as it won't get buried by suggestions *for* the list. Recommendations on list formatting and categorization are particularly welcome. A few notes:
* I will be removing the topic pleas when I feel they have been satisfied. So if you want to wash the shame of having your flair being *officially* recognized as lacking in the list, you will just need to recommend more books.
* No, I will not put in Jared Diamond. If you want a recommendation for *Guns, Germs, and Steel* go to the Barnes and Noble help desk or the New York Times book list. This is for recommendations by specialists.
* No, I will not put in Edward Gibbon. I can frankly think of few worse ways to introduce someone to Roman history than Edward Gibbon. Remember, we want people to like the topic, not think it is incurably dull.
|
AskHistorians
|
http://www.reddit.com/r/AskHistorians/comments/14094l/meta_book_list_meta_thread/
|
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"text": [
"General question (as in every sources thread): What about non-English language sources? Yay/Nay? Only for country specific topics? ...?",
"^^I ^^did ^^not ^^find ^^Edward ^^Gibbon ^^dull ^^at ^^all...",
"the way the posts are going I am seriously worried about hitting the character limit in a few days and, worse, making the list unwieldy. Any suggestions?",
"We often get questions of \"whats a good book on\" I feel like the list is perhaps not visible enough. Maybe we could add the links to our perma threads right after the FAQ on the sideboard. Or perhaps link to them IN the FAQ. ",
"Any room for more on the nature of colonialism in general (accross various empires, rather than focusing on a specific country)?\n\nAlso, I loved Peter Hopkirks books (Setting the East Ablaze: Lenin's Dream of an Empire in Asia, 1984 / \nThe Great Game: the Struggle for Empire in Central Asia, 1990 / \nOn Secret Service East of Constantinople: The Great Game and the Great War, 1994). \n\nDoes anyone know of any books similar to Peter Hopkirks subject matter? "
]
}
|
[] |
[] |
[
[],
[],
[],
[],
[]
] |
|
14c61l
|
Is it possible to make 3D contact lenses similar to 3D glasses given out at Movie Screenings?
|
I'm wondering if this is possible, or has been developed, cause I'd love to just pop some contacts in instead of buying 3D glasses every damn time.
|
askscience
|
http://www.reddit.com/r/askscience/comments/14c61l/is_it_possible_to_make_3d_contact_lenses_similar/
|
{
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"c7brvd4"
],
"score": [
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],
"text": [
"I think it's a great idea, and I see no reason it shouldn't be doable. Indeed, polarized contact lenses have already been [patented](_URL_0_). And whereas linearly polarized contact lenses to reduce glare like polarized sunglasses would be impractical (since the effect depends on the orientation of the lens), 3D movies use circular polarization, so the rotational orientation of each lens wouldn't matter. And I bet having the polarizer cover the eye's entire field of vision would produce a much more comfortable effect than looking through awkward glasses.\n\nAll of Balthanos's critiques are pretty easily dealt with, too: Let people buy these things on their own (so the burden of idiocy is on the consumer, not the theater); and if leaving polarizing eyewear on during the day were a safety hazard, polarized sunglasses probably wouldn't be a thing."
]
}
|
[] |
[] |
[
[
"http://www.invention.net/dudai.htm"
]
] |
|
42tx06
|
how can a 60hz monitor have a response time of 5ms when 1/60hz = 16.7 ms?
|
Shouldn't the "real" response time be 16.7ms, since if you give an input exactly after a frame, you will only see it 16.7ms later?
|
explainlikeimfive
|
https://www.reddit.com/r/explainlikeimfive/comments/42tx06/eli5_how_can_a_60hz_monitor_have_a_response_time/
|
{
"a_id": [
"czd36nv"
],
"score": [
8
],
"text": [
"The response time is usually the time it takes a pixel to change from black to white, or some predetermined gray to another gray value to estimate the average real usage. This will determine the amount of time it takes the average pixel to change to the updated value after a new frame is received by the monitor; the shorter the response time, the quicker the screen updates. If the response time is as long as a frame update interval, the screen never finishes updating, and you get a blurry mess when you are watching video or playing games; the shorter response time helps eliminate this effect."
]
}
|
[] |
[] |
[
[]
] |
|
4rs845
|
what is the root cause of what appears to be unequal treatment of minorities by police?
|
explainlikeimfive
|
https://www.reddit.com/r/explainlikeimfive/comments/4rs845/eli5_what_is_the_root_cause_of_what_appears_to_be/
|
{
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"text": [
"From my point of view as a late 20s black male. The root cause is cultural conditioning, and that is something that will never go away which is why I strongly believe it's a problem that will never be solved. Now if you don't know what I mean by cultural conditioning, everything from kids movies, TV shows, commercials, what you hear on the news etc has an impact on the way you think. It's so deeply engrained in our society that it's impossible to break. Caucasians automatically think, whether they are racist or not that African Americans are more violent. African Americans feel from a very young age that the world is against them, you hear it a lot in rap songs on TV shows etc, so the mind state is completely different. I was taught at a very young age that it isn't a fair playing field and it would be something that I will have to live with the rest of my life. Now luckily I am semi successful, and have a family of my own and a son, I find myself passing on those same teachings to him. Fair or unfair, it doesn't matter, some people call it white privilege and I don't necessarily see it as that. To me it's more so of a black disadvantage. ",
"Young black men are responsible for 50% of violent crimes. They tend to live in concentrated areas (Chicago, DC, ATL, Baltimore). Naturally cops are going to focus on the heavy crime areas because the people that live there need help\n\n\nThe problem is the cops focus on this area can be racist. Or it might just seem racist to the inhabitants. Say you pull over every young black male, obviously many are going to be innocent of serious crimes. But now they are harassed. And they might be breaking small crimes (weed, traffic, registration) so they are more likely to be arrested or ticketed."
]
}
|
[] |
[] |
[
[],
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] |
||
6cvu5t
|
do animals get sick from licking another of the same animal it's wounds/blood?
|
Is this possible to happen if it ever happens that is? Or do animals know this and never do it?
|
explainlikeimfive
|
https://www.reddit.com/r/explainlikeimfive/comments/6cvu5t/eli5_do_animals_get_sick_from_licking_another_of/
|
{
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"dhxsgt5"
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"text": [
"Whenever an animal hunts other animals and eats meat, they're eating some of their blood. Their stomachs just pulverize everything. Same for if they were to lick another of the same species. Same for humans, too, pretty much. Something like a blood transfusion would probably cause problems, though, because it bypasses the stomach. And humans can get problems from having too much iron, not sure if carnivores experience anything similar."
]
}
|
[] |
[] |
[
[]
] |
|
50t450
|
why can't a human be frozen while still alive, and jumpstart and come back to life when they thaw out (like avatar)?
|
explainlikeimfive
|
https://www.reddit.com/r/explainlikeimfive/comments/50t450/eli5_why_cant_a_human_be_frozen_while_still_alive/
|
{
"a_id": [
"d76p4us"
],
"score": [
2
],
"text": [
"Someone with more knowledge can come by with more info, but the primary reason is that our cells cannot withstand the ice crystals that form when they are frozen. When our cells freeze they rupture and die. If all of our cells freeze, they all die. "
]
}
|
[] |
[] |
[
[]
] |
||
21njka
|
What did Stalin do the first week of Barbarossa?
|
Stalin was slow to react to the invasion before he addressed his people and really respond. What was he doing during that first week?
|
AskHistorians
|
http://www.reddit.com/r/AskHistorians/comments/21njka/what_did_stalin_do_the_first_week_of_barbarossa/
|
{
"a_id": [
"cgez8sj"
],
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"text": [
"Stalin chose to let secretary of State Molotov announce the German invasion to the citizens of the USSR. According to Molotov's own words: \"[Stalin] didn't want to be the first to speak. He needed a clear picture. He couldn't respond like an automaton to everything. He was a human being after all.\" During the first couple of days Stalin was simply swamped in work, formulating a military answer to the situation at the front which was quite disastrous.\n\nAfter a couple of days though, Stalin seems to have suffered some sort of mental breakdown. After a meeting with, amongst others, NKVD-chief Beria and Molotov in Stalin's dacha he supposedly uttered these words: \"Everything's lost. I give up. Lenin left us a proletarian state and now we've been caught with our pants down and let the whole thing go to shit.\" After that meeting Stalin remained in his dacha and went incommunicado. According to Molotov 'Stalin shut himself away from everybody, was receiving nobody and wasn't answering the phone'. \n\nBecause conducting a war without the leader of the country in office is quite difficult seven members of the Politburo decided to go check on Stalin themselves. They found him 'thinner, haggard, gloomy'. He asked the Politburo-members if he would still be able to lead the country to victory. They responded favourably and Stalin was appointed head of the State Defence Committee. The next day Stalin returned to Moscow and on July 3rd he held his first radio speech since the German invasion. \n\nSo did Stalin really have a breakdown? According to Simon Sebag Montefiore's Stalin: Court of the Red Tsar (the main source for this answer) the breakdown 'was real enough: he was depressed and exhausted'. But Montefiore also points to quotes from Molotov and Politburo-member Anastas Mikoyan who said it was also 'for effect'. Stalin used his breakdown to see if he still had the trust of the Politburo. \n\nEDIT Request for the downvoters: if you don't like my answer, please do give an alternative or point me towards the mistakes in my answer."
]
}
|
[] |
[] |
[
[]
] |
|
5ng3cs
|
how do radio stations broadcast album art?
|
explainlikeimfive
|
https://www.reddit.com/r/explainlikeimfive/comments/5ng3cs/eli5_how_do_radio_stations_broadcast_album_art/
|
{
"a_id": [
"dcb9dxf"
],
"score": [
5
],
"text": [
"Radio stations have extra radio bandwidth that they don't need for the audio alone. They can use this bandwidth to send additional data to your radio such as the station name, song title, artist, or I guess the album art. It's essentially sending data over a wireless internet connection, point-to-point from the station to your radio. This is not an efficient connection though due to the distance and interference, so its uses are limited. \n \nYou usually need a radio capable of receiving this kind of data (and a station properly equipped) otherwise your radio doesn't know how to interpret this data and display it for you. It would just think it was noise and ignore that part of the signal. This system is also heavily regulated in how it can be used."
]
}
|
[] |
[] |
[
[]
] |
||
9yp7fi
|
What determines what wavelength of light is reflected from object?
|
If i have a green apple, shined on by light from sun. The apple appears green. Because all wavelengths of light are absorbed except for some that appear green to us. But what determines the color of the apple? Is it the size of the molecules on the apple surface?
|
askscience
|
https://www.reddit.com/r/askscience/comments/9yp7fi/what_determines_what_wavelength_of_light_is/
|
{
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"text": [
"The transmission/reflection spectrum of a material is a function of the [electronic structure](_URL_1_) of the molecules composing it. You can imagine an electron as a charge on a harmonic potential; the electric field in passing light excites the electron into an oscillatory motion. When the frequency of the excitory field is much slower or much faster than the electron, it doesn't move much and transmits most of the light. Near resonance, it absorbs more of the light, and just above resonance frequency, it reflects most. The overall reflection spectrum will have features of all of the atoms and molecules in the material; for example, you can see the contributions of various gases to the [atmospheric transmission spectrum](_URL_0_). If you want a more quantitative treatment of this, MIT opencourseware has [some good slides](_URL_2_) on the topic.",
"TL;DR: it's the number of protons in most common atoms on the reflective layer of apple surface. The most outer layer is transparent wax (try to scrub apple with knife, it's fun).\n\nWavelength of any photon is determined by it's energy. wavelength = planks constant * speed of light / energy.\n\nWhat defines energy of reflected photon? Amount of energy absorbed by electron that was \"hit\" by incoming photon.\n\nStory version. A photon \"hitting\" an atom of apple may transfer its energy (excite) to atom's electron. Electron, being weird quantum fella, can only absorb energy from certain discrete list of values, too less or too much and interaction doesn't happen. Now suppose the photon was just right and excited an electron to a higher energy state. Electron doesn't like to excited and uses quantum magic to emit a photon in random direction and drops to it's stable (lower) energy state. Emitted photon's energy is precisely difference between excited and stable energy states.\n\nWhy different atoms have different energy levels? _URL_0_\n\nMore broad article on particle radiation from particle deceleration _URL_1_"
]
}
|
[] |
[] |
[
[
"https://www.photonics.com/images/Web/Articles/2009/3/8/InfraredSpectralSelection_FLIR_Figure1.jpg",
"https://en.wikipedia.org/wiki/Electronic_band_structure",
"https://ocw.mit.edu/courses/electrical-engineering-and-computer-science/6-007-electromagnetic-energy-from-motors-to-lasers-spring-2011/lecture-notes/MIT6_007S11_lec29.pdf"
],
[
"https://physics.stackexchange.com/questions/160548/what-enables-protons-to-give-new-properties-to-an-atom-every-time-one-is-added",
"https://en.wikipedia.org/wiki/Bremsstrahlung"
]
] |
|
5gush7
|
the us is known as the "no vacation nation", the only developed nation without mandatory pto.
|
explainlikeimfive
|
https://www.reddit.com/r/explainlikeimfive/comments/5gush7/eli5_the_us_is_known_as_the_no_vacation_nation/
|
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"text": [
"\"Because why should I pay someone not to work?\" That's what it amounts to basically, you can always find someone for the same job that will work for less pay or less benefits.",
"Because there's no political will for it. Laws have to be drafted and passed through the Congress and then get signed by the President. Americans have been electing politicians who tend to side with business owners, and they don't want mandatory PTO. ",
"The USA is among the most anti-regulation cultures among the wealthy nations. This dates back to our history as (1) the world's first large democracy and (2) the product of a revolutionary war fought for independence from an allegedly overbearing government (of England).\n\nIn addition to our dislike of regulations, we also have a culture in which people identify with rich business owners -- many average people imagine \"in the future, that could be me\". So people often support efforts to avoid regulating businesses.",
"For 40 years, the U.S. and the Soviet Union fought a cold war, as the world's two superpowers.\n\nThe Soviet Union stood for communism, and this caused the U.S. to take the polar opposite position, to stand for unbridled capitalism. The cold war is over, but the culture that came from this is still there.\n\nSo even today, the U.S. struggles with things that every other country has long since agreed upon and solved. This is why we don't have mandatory paid vacation, why we struggle to provide our people with health care, and so on.",
"Because large corporations (who are opposed to more regulation, especially regulation that requires them to pay people who aren't working) have incredibly strong lobbying power with US Legislators.",
"It's not regulated, but in my 18 year professional experience it is kind of mandatory. Management would encourage pto (I was never one that needed to be encouraged, but knew people that had to be). They'd get a little shunned if they didn't. family members in less professional roles, let's say a mill/warehouse job got x amount of weeks earned and they'd happily take. Move to the service industry, like wait staff or retail...they can literally become slaves an although they've earned pto it's frowned upon. Perhaps I'm completely off with no statistics, just my work experience for over 20 years and family/friends.\n\nUS is still far behind on work/life balance, regardless. \n\nEdit: not literally, figuratively.",
"Before the 1960s most Europeans worked more than Americans. Then tax rates started going up for Europeans and down for Americans. Because the government gets 30-50% of the value of your salary but none of the enjoyment you get from a day off, it makes sense for people who are paying more in taxes to work less. See the work of Edward Prescott for more on that.\nPeople who work less get paid less, and most Americans would rather work more and get paid more. Those who feel differently can negotiate to work less or work part time. America is a big diverse country and there is no need for a one size fits all policy.\n",
"a couple things:\n\nthe US is not one set of regulations, to a European think of the states as the individual countries in europe. \n\ni get more PTO via employment negotiation. the least amount i have ever had in my working life was 40 per year, higher than in the EU.\n\nin the US a large federal government is frowned upon. we would rather do things ourselves than have big brother coddle us. it works for europe and that is cool, but he have backbones here. ",
"It's not about what makes sense or not. It's about culture. Every person here is a decendant of an immigrant. It takes grit, determination and a strong work ethic to just up and leave everything you know and work your butt of in some new place hoping for a better life. Take the fact that we have self selected for people who generally embrace the the narrative of 'hard work above all else leads to prosperity', throw in our Puritan roots and our general distaste for the government intervening in our lives (compared to other places) which dates back to the revolution. You end up with a culture that lends itself to this policy being viewed differently here than elsewhere in the world.",
"Capitalism. Most people in the US care more about making money right now than the well being of people around them or future generations.\n\nSource: I am an American.",
"workers are an expendable commodity and are just another profit drain. workers contribute nothing to my bottom line, they only serve to worsen my bottom line. fuck workers...they don't do anything for me. \n\nfirst you give them safer working conditions where they won't get injured, then they'll want 60 work weeks.\n\nonce you give them 60 hour work weeks, they are going to want Sundays off...\n\nonce you give them Sundays they are gonna want Saturdays too.\n\nThose greedy bastards, once you give them weekends - they're going to want a 40 hour work week too. \n\nAll of those things cut into my profits. Man Fuck the Workers. Once you give them weekends they're going to want me to stop polluting the rivers and lakes they go to to recreate.\n\nDammit - now they've got weekends and less pollution, now they are going to start wanting paid vacations. Fuck the workers...those bastards should be paying me for the priviledge of making me money...\n\n\n(pretty much any conversation about workers rights in this country including but not limited to: vacation, minimum wage, executive pay, environmentalism, pollution control, child labor, gender pay gap, work place safety)",
"Whether I agree or not, the idea is essentially that deregulated market competition should balance out the need for regulation.\n\nCompany A and Company B are both trying to hire employee C; Company A and Company B are both free to structure the job/hours/dress-code/etc., as they please, and employee C is free to choose.\n\nSo you have Company A and Company B who are each attempting to hire the highest caliber of employee for their field from the same pool, and the best way to hire the best talent is through the best available employment package an employer can offer.\n\nCompany A offers 20 days of PTO, Company B offers 15. Employee C goes with Company D because they allow you to bring your dog to the office.\n\nIts the idea of competition in lieu of regulation as a stabilizer for equality.",
"And even if you get PTO good luck trying to use it and not be given a guilt trip or told you're \"Not a team player\". Get 3 weeks vacation, so far gotten to use 1.",
"People seem to be dancing around the truth of the matter. The truth is our \"democracy\" is almost 100% controlled by business, especially big business. Our laws are decided upon by businesses through lobbying, not politicians trying to better our population.",
"The \"No Vacation Nation\" wasn't actually the first title they came up with. Initially, they floated the idea of \"Vote against your own self-interest Nation\". Critics considered it too confusing. Then they tried \"The No Minimum Wage Nation\" but test audiences were skeptical that this would be too revealing. So the suits settled on \"No Vacation Nation\" as they knew they could maximize bootstraps much easier from the common worker using this terminology. ",
"Long story short: American political attitudes tend toward defining fairness as defending the interests of the powerful back to our founding. We've had a few bouts of progressivism, but they were short-lived and generated massive backlashes from the moneyed elites.\n\nHealthy happy workers are not necessary because workers are expendable in the eyes of big capital. Who cares about the long run when executives and shareholders have only temporary interests in business and superficial interests in society, with every interest in maximizing short term profit before moving on to the next venture? Those companies that do offer benefits only do so when the job market demands it. Huge numbers of Americans do not have enough demand for their work to be able to get any benefits beyond a flat hourly wage or commission.\n\nIt took a war that killed half a million to end slavery and huge chunks of the country's land were acquired by brute force against Native Americans and Mexico. People are still trying to abolish the minimum wage and any guarantee of healthcare, food or housing. People still protest the existence of food and drug purity and labeling and environmental protection.\n\nThe average American voter favors progressive policy when asked about specifics, but votes the opposite when the time comes. This is partially due to lack of information on policy and partly due to the idea that we are all kings in our own right and the state cannot tell us how to do business or handle our property.\n\nIt's the best country in the world to live in if you make an upper middle class living or better, but the majority have little more than trinkets and distractions to mark their lives as better than those of medieval serfs. And every serf dreams of being a lord. And there is some genuine philosophical agreement with libertarian principles and some genuine corruption.\n\ntldr: Protections for the little guy in the US are the exception to the rule and those that exist are under constant assault while others are trojan horses that hurt the little guy while claiming to protect him because 'Murica.",
"But who takes a job that does not have vacation time? I have never had a job unless I was the owner that did not have vacation time. There are choices to be made and by not taking jobs with no paid time off will make employers provide it. So in thinking about this there is a group who have no paid time off in my company. The thing is they work for 3 weeks and then have 3 weeks with no work essentially only working 6 months a year and they make 100k plus a year. ",
"because US business does not give a damn about the US worker\n\nUS business cares about profits. it uses those profits to buy politicians that pass regulations that will not decrease profits\n\nexecutive bonuses are threatened? layoffs.\n\nshareholder dividends are threatened? layoffs.\n\nless regulation in another country? close US production.\n\nUS employees too expensive? H1Bs and illegal aliens. \n\nyeah, you read that right. why do illegal immigrants come to the US in search of higher wages? because US businesses pay them. its a fraction of what US residents would earn but that's ok - it reduces prices for consumers and increases profits for companies.\n\nwanna solve the problem of illegal immigration? fine businesses found hiring illegal aliens out of existence. \n\ndon't get me started about healthcare - no job, no health insurance, too damn bad.\n\nso that's why US workers get little vacation time",
"Because we don't fuckin need to. Everybody with a full time job gets vacation time or their company won't have anybody filling their positions.",
"Wow, amazed at some of the crappy responses here. Lots of people saying mandatory isn't required, typically coming from people who work for companies that DO provide it, which are in general, well-paying jobs of a higher status. So, because a typical well-off American already gets PTO, they don't consider it important that workers of every level in America recieve PTO. The issue is not about PTO; it's about Americans feeling it necessary that they be better than others. So, they don't consider a fast food employee for example, as someone deserving of PTO- they are not worthy enough, they don't work hard enough, and they aren't skilled enough- only upper class or upper middle class Americans should have that privilege. It's really sort of like a caste system; the upper class constantly want to deny benefits to the lower class so they can retain their privileged status, and when any issue revolving around the matter is brought to the surface, the status quo is quick to jump on it and defend a system in which they benefit and others suffer. It's not fair, and the onyl motivation for it is that Americans like to look down on and trash those less fortunate by saying things like, \"well we don't need PTO for all employees- this job doesn't deserve it anyway,\" and \"Americans don't want the government requiring it,\" when the majority of Americans actually do support mandatory vacation time, albeit the majority of the poor and powerless, so it will never garner attention, and you can't rely on the majority and the powerful to raise the issue in the defense of the other side, because those are the same elitists who benefit from NOT having to pay people for time off, and also the same people who get off on being \"better\" than other Americans because they are fortunate enough to get PTO anyway.",
"This is the worst ELI5 of 2016. Like by far. This is not the platform to push your agenda on. Make some whiney post on /r/politics, they'll love you there /u/usscan"
]
}
|
[] |
[] |
[
[],
[],
[],
[],
[],
[],
[],
[],
[],
[],
[],
[],
[],
[],
[],
[],
[],
[],
[],
[],
[]
] |
||
1ci7j1
|
Mathematically speaking, if a given game of Sudoku, in its initial state, has only one possible outcome, will it always solvable without having to resort to guessing a cell's value?
|
I have long felt this must be the case, but my limited mathematical skills prevent me from proving this
|
askscience
|
http://www.reddit.com/r/askscience/comments/1ci7j1/mathematically_speaking_if_a_given_game_of_sudoku/
|
{
"a_id": [
"c9gs72u",
"c9gttjh"
],
"score": [
3,
3
],
"text": [
"Sure, if it has a unique solution, it's \"solvable\" by giving that unique solution. Whether it's solvable by some particular algorithm is going to be very dependent on the details of that algorithm.",
"Unless the person who made the puzzle made a mistake a sudoku puzzle has only one correct solution and enough information from the start to solve it without guessing."
]
}
|
[] |
[] |
[
[],
[]
] |
|
7oam2x
|
How can I find a certain persons coat of arms from the 1000s?
|
I’m trying to find Robert “the admiral” Le Blount’s coat of arms. He was a companion of King William the conqueror.
How would I go about finding his coat of arms?
|
AskHistorians
|
https://www.reddit.com/r/AskHistorians/comments/7oam2x/how_can_i_find_a_certain_persons_coat_of_arms/
|
{
"a_id": [
"ds8hnfb"
],
"score": [
3
],
"text": [
"You almost certainly won't find it at all. Formal heraldry, in which each individual possesses a unique, identifying coat of arms based on symbols inherited from the father and mother, did not develop until the 13th century. It's likely that 11th century Normans decorated their shields, but this would have been cosmetic rather than heraldic in nature."
]
}
|
[] |
[] |
[
[]
] |
|
16f8mj
|
What happened to all the Aquatic Dinosaurs?
|
I'm curious as to why the aquatic dinosaurs disappeared. I know there are a lot of theories and hypothesis as to why the land dinosaurs were wiped out, but it seems that sea life has been left out of this discussion.
For example, the asteroid. How did that affect the ocean?
|
askscience
|
http://www.reddit.com/r/askscience/comments/16f8mj/what_happened_to_all_the_aquatic_dinosaurs/
|
{
"a_id": [
"c7vgxjp",
"c7vhe19",
"c7x3kgw",
"c7y8asn"
],
"score": [
2,
34,
3,
2
],
"text": [
"For some of the part, lots of sea creatures survived. Look at sharks, they've been around for a very very long time. An asteroid strike would have also affected the water, it would have been to cold for some animals in more tropical seas to have survived, areas would have iced over too.",
"First off, the obligatory \"Giant marine reptiles were not technically dinosaurs\" (some were actually pretty closely related to certain lizard groups, others were in completely different groups, none were dinosaurs proper)\n\nSecond: These marine reptiles tended to be large, active top predators. Life is always a bit more precarious for top predators. Blot out the sun for a few years and you'd see phytoplankton populations crash, leading to a crash in small fish. This would decrease populations of the larger fish that top predators eat. Lacking food, many would starve. And top predators usually have pretty low populations because their food supply is limited even during the best of times, and each individual needs to eat a lot. Fewer individuals mean lower chance of survival.",
"This isn't an archaeology question, but a paleontology question. ",
"This does not belong in archaeology. This is geology or paleontology"
]
}
|
[] |
[] |
[
[],
[],
[],
[]
] |
|
a7gt32
|
when i’m driving, the wind can blow my car all over the road. when i’m parked, the wind can’t move my car one inch. why?
|
[deleted]
|
explainlikeimfive
|
https://www.reddit.com/r/explainlikeimfive/comments/a7gt32/eli5_when_im_driving_the_wind_can_blow_my_car_all/
|
{
"a_id": [
"ec2uq01"
],
"score": [
7
],
"text": [
"But it does move your car. If you're driving down the road and a gust of wind hits the side of your car it's going to push it off to the side until you correct it. That's because your car is already in motion but it's shifted slightly to the side during that motion. However while it's parked that same gust of wind will cause it to rock back and forth a bit. The only difference is that it doesn't feel as extreme because you're not in motion. "
]
}
|
[] |
[] |
[
[]
] |
|
4dl2of
|
why do the us elections need donations? what for? what would happen if that was not allowed?
|
explainlikeimfive
|
https://www.reddit.com/r/explainlikeimfive/comments/4dl2of/eli5_why_do_the_us_elections_need_donations_what/
|
{
"a_id": [
"d1ry4hd"
],
"score": [
2
],
"text": [
"Funding for the various candidates does not come from the Government in the US save for a very small pool of funds used to get things started. So the money that the candidates use has to either come from their own personal savings, come from party coffers, or come from donations made directly to them for the campaign. \n\nThe parties also do not charge dues from their members as is common in many European countries. So all money that the parties have is from donations made to the party, or unused funds from candidates as they full out of the race. \n\nThe money that is collected is spent on the campaign. You have the costs of paying workers in every state to spread word of your campaign and your stances, paying pollsters to collect data, paying campaign managers and policy advisers, paying for ad time on TV and in other media, travel costs to go do speeches and to attend debates, renting locations for various events, etc. Money that is not spent can be used to reimburse any personal money spent, donated to charity, or sent to the party general fund. \n\nIf donations were not allowed the richest person would win elections because they would be able to buy the most ads and get their platform known to more people. "
]
}
|
[] |
[] |
[
[]
] |
||
2feqql
|
Why are 6- (and sometimes 5-) membered rings far more prevalent in chemical compounds than rings with 4 or 3 members?
|
askscience
|
http://www.reddit.com/r/askscience/comments/2feqql/why_are_6_and_sometimes_5_membered_rings_far_more/
|
{
"a_id": [
"ck8lf58",
"ck8ljlc",
"ck8lo8y"
],
"score": [
7,
2,
3
],
"text": [
"3 and 4 membered rings have high energy bond angles that are strained and unstable. 5 and 6 membered rings allow the bond angles to relax and that allows the compound to be more stable and energetically favorable. ",
"It's due to the energy required to form bonds at certain angles away from neutral/most energetically favorable/ideal. IIRC correctly, for single-bonded carbons the ideal angle is 109.5 degreed (tetrahedral). \n\nThe angles required to close a six-member ring require the least amount of energy. Smaller ring will close the angles more than they want to close, larger ring will open the angles more than they want to close. This causes what is known as ring strain. \n",
"Bond angles are unfavorable in small saturated rings and have high bond strain. You can see this by using a model kit. Bonding/anti bonding orbitals are highly eclipsed and this results in a high energy, strained scenario. Non bonded interactions can add to this effect. Still, 3 members rings exist (cyclopropane, bicyclo[1.1.0]butane, cyclopropene, etc.) but 60 deg and less angles are far from ideal tetrahedral geometry. Common rings have what's called Pitzer strain, while large rings have little or no strain at all. Strained molecules have a higher potential energy when bonds are forced to make abnormal angles. Since nature tends to conserve energy whenever possible, small rings (below 5) are unusual. There are a few examples known - such as the 4-membered ring in penicillin (beta lactam ring system). Small conjugated ring systems tend to spontaneously rearrange to \"more favored\" spacial/energetic arrangements (e.g., Cope rearrangement). TL;DR rings are stable, except when they aren't. "
]
}
|
[] |
[] |
[
[],
[],
[]
] |
||
192srr
|
If it was possible to look at from close, what would the ignition of a star look like ?
|
Would it be "on fire" before it ignites ? Does it basicly creates a huge explosion sending a shockwave out ?
Thanks in advance
edit: Also, i suppose close is a relative term here. I'm saying close enough for a global view of the sun in good details.
|
askscience
|
http://www.reddit.com/r/askscience/comments/192srr/if_it_was_possible_to_look_at_from_close_what/
|
{
"a_id": [
"c8k9xcw"
],
"score": [
19
],
"text": [
"It wouldn't be easily perceivable. Externally, it's actually a gradual process. Most people don't appreciate that stars begin their lives hot even before fusion starts. This is due to the energy of gravitational contraction. When you compress something to make it smaller you heat it up, and a proto-star is very highly compressed (through gravity) compared to the light-year sized nebula that spawned it. All of that energy that used to be in the form of gravitational potential energy is now in the form of heat.\n\nAs the star contracts the surface will stay at around the same temperature though the core will get hotter until fusion kicks in. Afterward the star will heat up a bit and contraction will halt as an equilibrium between fusion energy production and heat output becomes balanced. Interestingly, stars generally become better behaved and large explosive outbursts become less common as fusion kicks on. This is because in the early stages the primary mode of heat transport is convection (due to the high opacity of the plasma), which isn't very efficient and leads to large variations in temperature on the star (which can cause violent flares, mass ejections, and contributes to a very strong stellar wind). As the interior of the star heats up, radiative energy transport becomes more prominent and the star becomes differentiated into layers of material that are all at very close to the same temperature at a given radius from the core."
]
}
|
[] |
[] |
[
[]
] |
|
1otyor
|
How did attacking a city generally work in the 11th/12th-ish centuries?
|
AskHistorians
|
http://www.reddit.com/r/AskHistorians/comments/1otyor/how_did_attacking_a_city_generally_work_in_the/
|
{
"a_id": [
"ccvz6lk"
],
"score": [
5
],
"text": [
"I will assume that you mean Europe, and specifically Western Europe.\n\nA walled city was a very tough nut to crack for any attacking force. A walled city would have the local militia, and quite likely at least a small garrison of professional soldiers under the employ of the liege. \n\nNow, an army needed to have overwhelming force if they were to attack a fortified city. Sun Tzu states that a three to one advantage is needed, but even that wasn't always enough. At the [Siege of Rhodes](_URL_0_), the Knights Hospitaller, numbering only about 3,500 knights and soldiers, held off 20,000 soldiers, including 3,000 janissaries of the Ottoman Empire. \n\nObviously, the quality of the attacking and defending forces means a lot in a situation where one is actually going in in that fashion. Such a means, however, usually wasn't the case. Sending your men at the walls with ladders, rams, and towers was usually only done when the city HAD to be taken, usually because reinforcements were coming to help the defenders, or other such situations.\n\nTypically, it would turn into a siege. Simply put, during a siege, the attackers were trying to wait out the defenders. If possible, entrances to the city would be blocked off, your own forces would entrench (protecting them from the defenders as well as possible reinforcements), and you would starve out the defenders. \n\nThis was not always easy. Sometimes the attacking force could not block all points of supply, such as if the city were on the coast, had several gates, or the attacking force was small. Cities could hold out for months of years in this fashion. Many cities had their own sources of water such as wells within the walls for just such a situation. There were usually supplies inside for at least a short siege. Things could get pretty dire, however, with people eating horses and mules, and sometimes even people.\n\nThis isn't to say the situation was great for the attackers. Dysentery was very common with besiegers, and the risk of disease decimating an attacker was huge. In pre-modern armies, disease killed more soldiers than anything else by a huge margin. \n\nAttackers, as stated, also had to worry about reinforcements coming to aid the defenders. Often, besiegers would build a fortress around the city, made of wood or other materials, to protect themselves from defenders sallying forth or attempts to break the siege.\n\nAnd, of course, the attackers had to worry about supply as well. During the First Crusade, the crusaders ran so low on supplies that they would cut meat from dead soldiers and horses and eat it.\n\nIf the defenders surrendered early, they might expect some mercy (ie not be killed in the streets). If they tried to fight it out, there was typically no mercy. Either way, looting was very common, and soldiers generally expected to supplement whatever pay they were given with this looting of cities."
]
}
|
[] |
[] |
[
[
"http://en.wikipedia.org/wiki/Siege_of_Rhodes_(1480)"
]
] |
||
3lai0z
|
basic bonsai tree care.
|
explainlikeimfive
|
https://www.reddit.com/r/explainlikeimfive/comments/3lai0z/eli5_basic_bonsai_tree_care/
|
{
"a_id": [
"cv4kync"
],
"score": [
2
],
"text": [
"Bonsai are trees that are deliberately grown in a way to dwarf them, and are often sculpted into specific shapes. So you start with the standard \"give it the right amount of water, food, pot space and light\" that applies to almost all houseplants. \n\nBut the species, age and size of the bonsai all make a huge difference in how much of each it should be given when, and how it should be pruned. \n\nSo to avoid posting a book, it's probably best you go to bonsai care-related sites like this one: _URL_0_\nand look up the specifics. "
]
}
|
[] |
[] |
[
[
"http://www.bonsaiempire.com/basics/bonsai-care"
]
] |
||
1us9jm
|
gold trading and how it's used to "back" currency and the like
|
The gold standard and so forth. If this has been asked before I wouldn't know because the search isn't working. That's my excuse and I'm sticking to it.
|
explainlikeimfive
|
http://www.reddit.com/r/explainlikeimfive/comments/1us9jm/eli5_gold_trading_and_how_its_used_to_back/
|
{
"a_id": [
"cel7q2c"
],
"score": [
2
],
"text": [
"Gold was money, used in trade, made into coins or bullion, sometimes by governments, most often by gold specialists.\n\nCurrency is a substitute for the real money (though not only gold was used as money). Currency was usually a paper substitute for real money that were called \"Bank Notes.\" Ideally, for every one unit of currency, there should be an equal amount of actual money secured somewhere, usually a bank's vault. \n\nInstead of trading the gold itself, because it was a heavy metal and could be a target of robbery, people would leave the gold in the vault and trade the paper notes (that could be kept in pocket, even in large denominations) that represented a claim to the gold in the vault.\n\nThe USA started with BOTH a gold and silver money system. An ounce of silver was $1. An ounce of gold was $20. These were denominations set by law. About 1873 the government stopped allowing people to bring silver to the mint to make silver coins. So, essentially gold was the only public money, and all Bank Issued Currency (and all currency is bank issued, with one exception during the civil war era) was denominated by dollars, but \"backed\" by the appropriate proportion of gold money.\n\nThat means, theoretically, anyone should be able to take the piece of paper they got from trading to the bank that issued the paper, and get gold. FDR outlawed Americans from doing that in 1933 (and confiscated peoples gold money), and Nixon outlawed foreigners doing in in 1971 (which was only partly allowed after WWII though the \"Bretton Woods\" agreement.)\n\nThe reality was, of course, far more paper currency was made than ounces and tons of gold to back it up. Which is ultimately why a \"gold standard\" usually becomes a fraud."
]
}
|
[] |
[] |
[
[]
] |
|
5xo4jx
|
why does the speed of a car seem slower when i'm inside it rather than outside?
|
explainlikeimfive
|
https://www.reddit.com/r/explainlikeimfive/comments/5xo4jx/eli5_why_does_the_speed_of_a_car_seem_slower_when/
|
{
"a_id": [
"dejnh9s"
],
"score": [
7
],
"text": [
"Relativity!!!\nwhen you are in a car you are in car's frame (in other words you are moving with speed of car) and when you look from window all objects have a speed equals to object's speed minus car's speed (vector addition) which slows down everything which seems to you like car is moving slow"
]
}
|
[] |
[] |
[
[]
] |
||
7ch067
|
how does the body correctly sort food and fluid (especially when you eat and drink together)?
|
For example I have seen some eating contests where the participants eat huge quantities of food and drink water to held them “down” it quickly.
When it gets down your food pipes* how does the stomach and bladder get their individual shares of what’s been consumed??
*forgot the sciency name.
|
explainlikeimfive
|
https://www.reddit.com/r/explainlikeimfive/comments/7ch067/eli5_how_does_the_body_correctly_sort_food_and/
|
{
"a_id": [
"dpprmcr",
"dpprnim"
],
"score": [
3,
12
],
"text": [
"The bladder is not directly connected to the digestive system, so there's no \"sorting\" involved. The small intestine extracts water and nutrients from the food in to the blood, with the help of friendly bacteria, and you poop out what's not used with a lot of dead bacteria. The kidneys, on the other hand, filter impurities and waste products out of the blood, with some water, and sends them to your bladder. ",
" > When it gets down your food pipes* how does the stomach and bladder get their individual shares of what’s been consumed??\n\nThe sorting happens in the intestines. It makes intuitive sense that the solids you eat become poop and the liquids you drink become pee, but that isn't actually true! \n\nEverything you swallow goes to your stomach, where it all gets mixed and broken down into a soup-like consistency. Then it goes to the intestines. Your intestines absorb the water out of it (including water that used to be in solid food), and absorb the nutrients. What's left over at the end of all this absorbing is poop. Poop also contains a lot of old, dead cells from the intestinal walls, and bacteria. \n\nAll the water and nutrients that got absorbed will flow around in your bloodstream, going where they need to go. Once this is done, the extra water is filtered out by the kidneys, because a lot of the waste products we need to pee out (like urea) have to be dissolved in water. "
]
}
|
[] |
[] |
[
[],
[]
] |
|
25mzw4
|
Why were there fewer African American soldiers in Vietnam than in other American-waged wars?
|
I recently learned that 3.14% of our military was African American during Vietnam - and thought the number seemed quite low.
EDIT: thank you u/KNHaw for kindly showing me the correct percentage (12.6%). Sorry for the misinfo!
|
AskHistorians
|
http://www.reddit.com/r/AskHistorians/comments/25mzw4/why_were_there_fewer_african_american_soldiers_in/
|
{
"a_id": [
"chirlo3"
],
"score": [
22
],
"text": [
"It does seem unusually low. Where did you get that statistic? [This site](_URL_0_) claims (my emphasis):\n\n > The Vietnam War saw the *highest proportion* of blacks ever to serve in an American war. During the height of the U.S. involvement, 1965-69, blacks, who formed 11 percent of the American population, made up 12.6 percent of the soldiers in Vietnam... the percentage of black combat fatalities in that period was a staggering 14.9 percent.\n\nSource: *The Oxford Companion to American Military History*. 1999."
]
}
|
[] |
[] |
[
[
"http://www.english.illinois.edu/maps/poets/s_z/stevens/africanamer.htm"
]
] |
|
b8i8i9
|
why are germs so difficult to wash off, and yet so easy to spread?
|
explainlikeimfive
|
https://www.reddit.com/r/explainlikeimfive/comments/b8i8i9/eli5_why_are_germs_so_difficult_to_wash_off_and/
|
{
"a_id": [
"ejxwuf1"
],
"score": [
6
],
"text": [
"Because even a tiny bit that gets off or that remains can then apread to cover the whole surface in a relatively small timeframe, since when bacteria multiplies, its population size basically just straight up doubles."
]
}
|
[] |
[] |
[
[]
] |
||
2c87p1
|
why can some people only twist their tongues in one direction?
|
I thought since there is just one brain, one tongue, and one whatever else is inside people's heads that affects tongue twisting (muscles), that everything should be symmetrical. However, I, and I'm sure others, can only twist my tongue in one direction (clockwise). Why would this be if everything's supposed to be symmetrical?
|
explainlikeimfive
|
http://www.reddit.com/r/explainlikeimfive/comments/2c87p1/eli5_why_can_some_people_only_twist_their_tongues/
|
{
"a_id": [
"cjcvuh6",
"cjcwov7",
"cjczh2i"
],
"score": [
3,
2,
2
],
"text": [
"I can't twist my tongue at all. I just tried.",
"It is a purely genetic trait akin to having a widow's peak.",
"Whoa just realized that I can't twist my tongue two ways.\n\nWell it sort of works the other way but it's not quite the same."
]
}
|
[] |
[] |
[
[],
[],
[]
] |
|
1cnk4d
|
Is there any facts to back up the claim that before the Vikings came, North American Indians had a homogeneous culture that covered a large portion of the Continent but due to foreign diseases brought along by the Vikings most of them died out?
|
I forget where but I remember reading this. I remember it more of a theory than a claim. To clarify when I say north American I don't mean Aztec I mean what we would today call the US and Canada.
|
AskHistorians
|
http://www.reddit.com/r/AskHistorians/comments/1cnk4d/is_there_any_facts_to_back_up_the_claim_that/
|
{
"a_id": [
"c9i85xk",
"c9i8f4q"
],
"score": [
4,
2
],
"text": [
"You're kind of mixing up two different claims. And it's a little difficult to disentangle them in a short answer. You might start with the popular questions page topics about [Native Americans and European Diseases](_URL_0_).",
"I'd be interested to know where you heard this, because I think you may be jamming a few ideas together to come up with a misguided whole.\n\nThere are some generally recognized large geographic regions that serve as rough boundaries for [cultural areas](_URL_0_), but to say that there was a homogenous culture across the continent is just wrong. Even those generally agreed upon areas could shift with time and always held an immense cultural diversity in agricultural practices, lineage, religion, art, technology, architecture, and everything else that falls under the rubric of culture. Calling pre-columbian North America \"homogeneous\" is just so wrong it's hard to even know where to begin.\n\nAs for the Vikings bringing some sort of infection that depopulated the continent? No, there is no evidence of this. There's really very little evidence of any lasting effect of historically brief Viking settlement in Newfoundland. That's why they are a footnote in American history to the invasion Columbus kicked off, which did bring disease that spread out before the Europeans, depopulating as they went.\n\n"
]
}
|
[] |
[] |
[
[
"http://www.reddit.com/r/AskHistorians/wiki/nativeamerican#wiki_native_americans_and_.28european.29_diseases"
],
[
"http://www.american-indians.net/cultures.htm"
]
] |
|
2s0eqr
|
Can we tell the exact moment a subject begins to fall asleep by looking at the brain activity? Or is it a more gradual process?
|
Can we use electrodes or MRI's to pinpoint that moment where consciousness fades away? Like the last moment I remember before I fall asleep? If so, in which parts of the brain are most of the changes observed? Can we say that those parts are the seat of consciousness?
|
askscience
|
http://www.reddit.com/r/askscience/comments/2s0eqr/can_we_tell_the_exact_moment_a_subject_begins_to/
|
{
"a_id": [
"cnlejk3"
],
"score": [
11
],
"text": [
"The clear definition of sleep onset is not yet clear (mainly because people can report being awake, even though there are clear behavioral changes that can indicate the presence of sleep). There are various measures that can be used however to measure sleep onset.\n\n- EMG (electromyogram) shows a gradual decrease in muscle tone as sleep approaches.\n- EOG (electrooculogram) shows slow possibly asynchronous eye movements.\n- EEG (electroencephalogram) will show different 'types' brainwaves that depend on different sleep stage\n\nGenerally it is thought that EEG changes to stage 1 sleep, accompanied by slow eye movements identifies the transition to sleep. So to answer your first question, it is possible to quite reliably measure the onset of sleep. Not within the millisecond but generally within a couple of seconds. To answer your second question, in what part of the brain are the most changes observed is a harder question. An EEG measures mainly cortical activity and based on this activity can make inferences about what sleep stage someone is in. However, the brain areas that are responsible for initiating and maintaining sleep are subcortical areas (areas in and near the brainstem and midbrain) and can not be measured using an EEG.\n\nVarious other measures have been used to discover which brain areas are involved in sleep (lesion studies, MRI, ERP etc). The current view proposed by Saper is that the transition between wakefulness and sleep is governed by a 'flip-flop switch' between various arousal promoting neurotransmitter systems in the brainstem and midbrain involved in waking (such as noradrenalin, histamine, acetylcholine, serotonin, dopamine) and the ventrolateral preoptic area (VLPO) involved that uses the neurotransmitter GABA. Oxerin/hypocretin plays an important role in the interaction between these two systems through the flip-flop switch i mentioned earlier, a good overview of all this is given in this short video (_URL_0_).\n\nConsciousness in the sense of being active and responsive (which relates to sleep and therefore to measures of arousal and attention) and consciousness in the general sense (which is way more complex and involves more things) are two different things. But looking at sleep definitely gives us an understanding of one part of what consciousness is.\n\nSources: \n- Cascardon & Dement - Normal human sleep: an overview\n- Saper - The neurobiology of sleep\n"
]
}
|
[] |
[] |
[
[
"https://www.youtube.com/watch?v=4KbxyDTc4x8"
]
] |
|
2rtjk5
|
why is the "peace sign/victory sign" with two fingers used with positive connotation, if it was first used by winston churchill, a british man, and the "v-sign" is an offensive hand gesture there?
|
During the second world war, Sir Winston Churchill, the British Prime Minister used his index and middle fingers to form a "v-sign", which was then used as a symbol for victory and has that connotation throughout Western Culture; in England, a country fighting on the same side of the war, sees the same gesture as an obscene and offensive sign. Why did this come to be, and further from that, was the hand gesture offensive before Winston Churchill used it in this way?
tl;dr: Why is the "v-sign" offensive in England but not in Canada/the USA?
|
explainlikeimfive
|
http://www.reddit.com/r/explainlikeimfive/comments/2rtjk5/eli5_why_is_the_peace_signvictory_sign_with_two/
|
{
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"cnj52io",
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],
"score": [
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3
],
"text": [
"Sorry I only have time for a small part of an answer, but take a careful look at the position of the palms when people make these signs: v-sign with palm out means \"victory\" or \"peace\", v-sign with palm in means \"the finger\" in the UK and its relatives.",
"The offensive V sign is \"The Longbowman's Salute.\" The story goes that since Britain had the best archers/bows, whenever the French would capture one they would cut off the two fingers used to pull back the bow. As a result, archers would taunt the French by waving their fingers at them. I'm not sure how much of that actually happened, but that's the story."
]
}
|
[] |
[] |
[
[],
[]
] |
|
10vygi
|
Why was the Ashanti "Sika 'dwa" translated as "Golden Stool", not called the "Golden Throne"?
|
Is it because of the colonialism at the time it was first translated, because the African cultures were looked upon as being primitive? "Throne" would better convey the meaning and purpose of this item. ([More info about the Golden Stool on Wikipidia here](_URL_1_)) Basically I'm looking for a knowledgeable person to shed more light on the history of the choice of the word "stool".
**Definition of "stool" via _URL_0_:**
> 1. a single seat on legs or a pedestal and without arms or a back.
> 2. a short, low support on which to stand, step, kneel, or rest the feet while sitting.
It technically fits the first definition; however, the word "stool" strongly implies an informal, even crude seat.
**Definition of "throne" via _URL_0_:**
> 1. the chair or seat occupied by a sovereign, bishop, or other exalted personage on ceremonial occasions, usually raised on a dais and covered with a canopy.
> 2. the office or dignity of a sovereign: He came to the throne by succession.
> 3. the occupant of a throne; sovereign.
> 4. sovereign power or authority: to address one's pleas to the throne.
> 5. an episcopal office or authority: the diocesan throne.
The word "throne" has the obvious benefit of having the implications of importance, power, prestige, and royalty, even holiness. All of these are missing from the word "stool" and, in the English language the connotations of "stool" make it laughable to think one as being royal or holy.
|
AskHistorians
|
http://www.reddit.com/r/AskHistorians/comments/10vygi/why_was_the_ashanti_sika_dwa_translated_as_golden/
|
{
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"text": [
"I think, you kinda answered the question yourself: it is a stool- not a throne (nor a chair).",
"Slightly unrelated: stools were also given as grave goods in some Bronze Age burial mounds and Iron Age graves in Denmark and Germany, also regarded as symbols of power but still called 'stool' in the literature. Similarly, in the Caribbean chiefs also had special stools.\n\nI am unaware of the semantics behind the distinction between a stool and a throne, and I guess that a throne could be either a chair or a stool, as your dictionary quotations show. Still, you must agree that these portable seats are quite different from, for example, [Charlemagne's throne](_URL_0_).",
"Translation is a major locale where meanings get changed in sometimes unconscious ways. The reason it's translated as \"Stool\" and not \"Throne\" in English from the Twi original is the same reason that the Zulu & Xhosa \"iSizwe\" was translated by 19th-century traders and missionaries in English as \"tribe\" and not the far more (but not 100%) correct \"nation\": the choice was made by English-speakers who were concerned with using a word that conformed to their notions, not the sense necessarily intended by the term in its original language. It may help in both cases to know that the term entered popular use in the 19th century, when such societies' \"place\" in the hierarchy of civilizations was presumed to be at the bottom so the choice of a term that conveyed a sense of parity would have seemed utterly incorrect and even nonsensical.\n\nSo you are correct that the invocation of a mere stool was a product of its day. But it *did* serve to objectify and reduce the Sika'dwa as a mere symbolic fetish for the superstitious. This is part of why the British governor made the incredibly myopic demand to \"sit on the stool\" that provoked Yaa Asantewaa's rebellion in 1900; he had no idea what he was misunderstanding, or that he was even misunderstanding it. It was not a deliberate diminution, but the ethos of the era, that suggested \"stool\" was a fitting translation; that wasn't helped by the fact that there is no English term for \"a symbol and seat of governance that is in the form of a low, backless, armless seat\" and the Victorians weren't about to import a Twi term to accommodate it. A lot of words got that treatment because Europeans, Eurafricans, and heavily missionized Africans were in charge of making equivalencies in European languages official. (Languages in which Africans made key contributions to the rendering of English show a bit less of this, for example in the Yorúbà bibles of Rev. Samuel Ajayi Crowther.)\n\nYou'll find a lot of words that still seem to be frozen in some weird colonial-era translation vortex for precisely the reason that, as you point out at the beginning, the translation was set down in the colonial era. Those things tend to move slowly, and in the interim, sometimes the terms get appropriated and \"remade\" themselves. I would argue that the Golden Stool as a proper noun has become one of those; people within the Asanteman and the *Asantehenes* themselves after Prempe I's return have infused a great deal of meaning back into the term. It's been effective enough that the elevation of an *Asantehene* is referred to as \"enstoolment,\" in a back-formation that elevates the Golden Stool to the status of a different but representationally analogous kind of throne.\n\nAs to who actually made the coinage and why they personally did it, I think we'd have to look back a long way--possibly via Dutch *stoel* which isn't just for stools, as they were at Elmina well into the 19th C.--to find the very earliest mentions. After all Europeans were right on the coast from the 1480s on. It's also entirely possible that the importance of household stools wasn't properly recognized either, so the translation started at the bottom and got applied upward. But I honestly have no idea where it first appears in English or Dutch."
]
}
|
[] |
[
"dictionary.com",
"http://en.wikipedia.org/wiki/Golden_Stool"
] |
[
[],
[
"http://m.seehuhn.de/images/aachen6-0600.jpg"
],
[]
] |
|
4a0nb7
|
when hearing a very loud noise, that blowing sound/feeling in your ears
|
Things like cement saws and angle grinders
|
explainlikeimfive
|
https://www.reddit.com/r/explainlikeimfive/comments/4a0nb7/eli5_when_hearing_a_very_loud_noise_that_blowing/
|
{
"a_id": [
"d0wfr2i"
],
"score": [
3
],
"text": [
"Sound is vibrations in the air. Loud sounds = stronger vibrations. If the sound is loud enough, you can feel the vibrations in your ear. "
]
}
|
[] |
[] |
[
[]
] |
|
1g60bl
|
Did Libraries face the same issues as Digital Media currently experiences?
|
In modern times there is much debate about the effects and legality of file sharing, resale of digital media, and piracy of the same. It occurred to me however that in many ways a traditional book Library is essentially the same thing. They provide free access to printed media to a great many people, without so much as charging a rental fee as a video store would. So my question is this...
**Have Libraries had to face the same issues that Digital Media currently experiences? Were publishers and authors against them? If so, how did different cultures deal with this and keep them open?**
|
AskHistorians
|
http://www.reddit.com/r/AskHistorians/comments/1g60bl/did_libraries_face_the_same_issues_as_digital/
|
{
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"text": [
"Copyright law is quite recent. \n\nYou probably ought to ask u/caffarelli about this matter, as it is her specialism.\n\nI published a brief case note on this issue late 2011, however, translated roughly:\n\n\"It was not until 1837 that Prussia and the German Bund introduced copyright law. Prior to this, authors needed to ensure sufficient compensation with their first publication run because, as soon as the text was available 'in the wild', no legal remedies were available against (in today's parlance) so called 'pirates', i.e. other publishing houses. It was this - from today's perspective - ironic situation that Immanuel Kant drew attention to in 1785 in his essay, 'On the Illegality of Book Republishing' with the following remarks:\n\n'The volume which the publisher allowed to be printed is a work of the author (opus) and belongs to the publisher after it has been printed or acquired in the form of its manuscript entirely, in order to do anything with it, as he desires, and which can be done in his own name; since this is the requirement of having a complete right to an item, i.e. ownership. The use, however, which he makes of it in a way not different from another [...] is a transaction (opera)[...].' (Kant in Berlinische Monatszeitschrift 5 (1785), p. 403 et seq.)\n\nInsofar as this, Kant distinguishes between the item (res) and transaction (opera). Fichte concretizes this idea: 'We could make two differentiations with respect to a book: the bodily aspect thereof, the printed paper, and the intellectual content.' Fichte, however, does not see a violation of ownership in the perpetuation of use of intellectual property without a license but, rather, a transaction without assigned agency [in Common Law: agency of necessity]: 'And how is the book republisher to be treated? He is taking possession - not of the property of the publisher, not of his intellectual content, not of his thoughts - but rather of the usufruct of the property. He is acting in the name of the publisher without having been given agency to this effect, without having reached a consensual transaction with him, and is seizing the benefits which arise from this representative position[...].' (Fichte in Berlinische Monatszeitschrift 5 (1793), p. 443 et seq.)\n\nIt is indeed the case that in ius commune as in today's valid German law the transfer of ownership of an item requires its physical transfer (ius commune: traditio), and for this reason Kant and Fichte consider it to be physically impossible to transfer ownership of the intellectual contents of an item. For this reason they speak exclusively of an usufruct and not - as in today's common and incorrect parlance - of 'theft' or 'piracy', but rather of agency of necessity. Viewed historically the polemicisation of the 'copyright' debate is clearly evident.\"",
"During the middle ages, unauthorized copying or stealing of books, which were considered then extremely valuable, was identified as a big problem. This led to a number of interesting solutions to fight such actions in libraries. \n\nFor example they used \"chained books\" or \"chained libraries\", where each book was chained to the bookshelf (see _URL_0_ ). \n\nHenry Petroski's book \"The book on the bookshelf\", gives interesting details on such issues.",
"As /u/peripatos said, this is sort of My Bag! So here's an uncomfortably large infodump.\n\nFirst, a disclaimer: I am an American librarian, educated in an American graduate library school, and working in the American academic library system, so what I know and am able to comment on will be about America libraries and American copyright. I am also writing this from a class I took 2 years ago, and a textbook I have long since sold back, so this might be a little hazy.\n\nAlso, as my husband is a proto-lawyer, I will add: none of this constitutes legal advice, and is provided just for your interest and reddit's general edification.\n\nYou should first consider that copyright deposit, that is, the now defunct requirement that you send a copy of your book to the Library of Congress to establish a record of copyright, was the major way the LoC and a few state libraries built their collection for many years. [Here's a short free article on how that worked.](_URL_2_) So that's one way copyright actually helped libraries!\n\nHowever, some publishers and authors have more or less been against public libraries from their \"beginning\" in America, and [some of them are still real buttholes about it.](_URL_0_) The classic argument is that libraries steal revenue from authors. Prior to the establishment of First Sale Doctrine in 1908, libraries were on pretty shaky legal ground. \n\nThe beginning of the American public library system is more or less pegged to the start of the Andrew Carnegie library building grants at the end of the 19th century, prior to that there were mostly subscription libraries with a few public libraries here and there. (There is also very much the effect of Dewey on the growth of libraries and the \"scientification\" of libraries at the same time period, and also the very elitist, conservative, classist aims of early public libraries in America, but I'm going to leave that stuff out as its not strictly speaking relevant to your question.)\n\nFor the past 100 years or so libraries in America have been functioning largely on a combination of two doctrines: First Sale Doctrine mentioned earlier, and Fair Use. Use of both these legal concepts are not always clear, and the public misunderstands them frequently, but they are most of what kept libraries running. First Sale dictates that once you buy a book (or CD, or DVD, or whatever physical thing) you can largely do what you want with it -- you can loan it to people for free, you can rent it for money, you can give it away, you can re-sell it. This means libraries can buy books and loan them as much as they want. However, this does not mean we can re-copy them, that is considered copyright infringement. Some recopying is considered legal under fair use, but its very complicated.\n\nTypically, e-books and other digital media are not technically speaking purchased, they are *licensed,* so First Sale does *not* apply to them. [Stanford Law Review has a good overview of this](_URL_1_). This means publishers can and will put whatever restrictions they want on e-books. Some restrictions I've seen: limits on the number of times an e-book can circulate (be checked-out), expiration dates on the file no matter how many times it has circulated, and charging way more for a library to buy the book than for a standard consumer. (Talking $70 a pop versus your $9.99, on top of these BS restrictions.) This is a lot of the reason your garden variety public librarian is not investing in e-books; other than the very start of the industry with Michael S. Hart, the inventor of the e-book in 1971 and founder of Project Gutenberg, which has always been very good to libraries, e-books have not been a smart use of limited book-buying funds.\n\nSo e-books are a new way to get around First Sale Doctrine. Old problem, new wrapping! Frankly, I think the days of weasel publishers \"licensing\" e-books are numbered, but the number is still pretty high. \n\nHappy to expand on anything or do follow-ups, as per usual. "
]
}
|
[] |
[] |
[
[],
[
"http://en.wikipedia.org/wiki/File:Libraries_in_the_Medieval_and_Renaissance_Periods_Figure_4.jpg"
],
[
"http://www.techdirt.com/articles/20130215/16442522003/bestselling-author-childrens-books-accuses-public-libraries-stealing-his-paychecks.shtml",
"http://www.stanfordlawreview.org/online/kirtsaeng-and-first-sale-doctrines-digital-problem",
"http://catalog.hathitrust.org/api/volumes/oclc/33140610.html"
]
] |
|
3dhcic
|
what and how are hot jupiters formed, and what does this mean about the creation of our own solar system?
|
explainlikeimfive
|
http://www.reddit.com/r/explainlikeimfive/comments/3dhcic/eli5_what_and_how_are_hot_jupiters_formed_and/
|
{
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"ct5aj3p"
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"Hot Jupiters are basically gas giants that orbit very close to it's star. Usually at half earth distance or closer (less than 0.5 AU), usually towards the closer end. As a result they get very hot, to the point of glowing from the heat.\n\nThe top theory about how they form is that they form at normal gas giant distance (Jupiter range, ~5 AU or more) and make their way inwards by slurping up the rocks and gasses closer to the star, causing it to gain mass and lose kinetic energy. Another theory is that the gravity of other planets or asteroids change it's orbit over time and bring it closer to the star.\n\nFor out solar system it doesn't mean anything special, only that we don't have a hot jupiter planet."
]
}
|
[] |
[] |
[
[]
] |
||
2crjck
|
the difference between a fee antivirus software like avg, and a paid antivirus software like norton 360?
|
Title
|
explainlikeimfive
|
http://www.reddit.com/r/explainlikeimfive/comments/2crjck/eli5_the_difference_between_a_fee_antivirus/
|
{
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"text": [
"Computer science major here so I know a bit about this stuff, I could drag this out but to try to explain simply, a number like 98% of viruses are just evolutions if precious viruses. All antivirus softwares look for these base differences. Free antivirus software finds these and eliminates. When you start getting paid software, their goal is to now try to up sell you from \"starter\" to premium. So paid programs like Nortan are notoriously hated for trying to be over protective blocking programs even trying to access the internet. Go for s free program like AVG, windows security essentials, or malware bytes I promise that if your computer ever gets Fubared to the point these can't fix it, not even Nortan can. \n\nTldr Why pay when free programs will do it without pissing you off",
"It depends from case to case the only way to give you a good answer would be checking what they offer and how often they upgrade. Which you can usually find on their product page.\n\n\n- some include firewalls, email checks, proxys, ... \n\n- some are only free for private use\n\n- some are just horrible\n\n- paid software may have the better support\n\n- free software may not include proxys, email check (which you may not even need) and are pay to upgrade\n\n\n\nbut \"good\" free antivirus software works just as good as a \"good\" paid software.\n\n\nEdit:\nThe most important thing is probably the update frequency. If your software only upgrades once a week you could already have the virus.\n\nBut everything else that got mentioned here (speed, efficiency, ...) depends on the software itself paying money for it doesn't have to make it better. But the nice thing with software is that even freeware can be awesome, because there are so many very talented programmers out there and the tools you need are mostly free.",
"I once read an article on this, and the following statement stuck with me:\n\n > One difference is that the paid AV software might protect you against a certain Virus, that the free one does not. The issue with this is that the Virus is so rare, it's like paying extra for your house insurance to protect you against a herd of Rhinos breaking down your walls. You just wouldn't.",
"I had a virus a few years ago that decided to use AVG as a vessel to reap havoc on my computer. This was not a typical virus and the person that made it was much smarter than the average bear, but it still left a bad taste in my mouth for freeware. I used the free trial of McAfee to get rid of it, but I ended up buying McAfee because it did the job credibly. I've had problems with AVG letting things slip before, and with paying a little extra, I think these companies get some extra funding to beef up their programs and increase their customer support.",
"For what its worth, from an Enterprise level, a commercial application adds administration functions. Distribution of updates can be controlled, then you have reporting alerting you to server / pc's requiring updates / not reporting, through to virus notifications. Also servers running Exchange (mail) will have different needs for AV scanning. Further to this, you also get support from the AV software vendor. Companies like McAfee also offer firewall and encryption products. "
]
}
|
[] |
[] |
[
[],
[],
[],
[],
[]
] |
|
62sz94
|
why peanuts without shells are way cheaper than peanuts with shells if it takes labor to shell them?
|
explainlikeimfive
|
https://www.reddit.com/r/explainlikeimfive/comments/62sz94/eli5_why_peanuts_without_shells_are_way_cheaper/
|
{
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"Could be a matter of scale / volume. I would imagine nearly all of the peanuts consumed are shelled to be eaten or made into peanut butter. Shelled peanuts are sold in comparatively much smaller volume. When you produce something in very large quantities, you are able to take advantage of \"economies of scale\" that drive the price way down. This is in part because your fixed costs (e.g. Production equipment) are spread out over much more output. ",
"The ones you buy shelled are taken from peanuts unfit to be sold with the shell on. Think damaged, discolored or otherwise just not great looking peanut shells. Same idea with baby carrots. They're cut from larger carrots that are discolored, misshapen etc.",
"3 things come to mind: economy of scale, where it's cheaper to process the nuts than it is to quality control the shells\n\n2- as said, shells may have a use elsewhere, and could make shelling them worthwhile\n3- container sizes: 200gm of unshelled peanuts probably takes up quite a lot less space than 200g of shelled peanuts, lowering the cost of logistics and storage. ",
"Maybe the majority of the peanut usage goes to shelled peanuts and their products leaving a lesser amount to be sold unshelled, making them more expensive. Idk, just a guess.",
"However, peanuts inside the shells are pure peanuts, and have not been handled, or licked by rats.",
"My fiance worked in a peanut shelling plant for years and it basically boils down to them wanting to get equal profits from shelled vs. unshelled.\n\nOnce the peanuts are shelled, they're graded and sold for different prices. There's splits, jumbos, mediums, #1s, etc. I forget all the names, but there's a few more. Even the hulls and 1416s (aka the smallest bits that fall through the sorting screens) can be sold for things like livestock feed and some other random things.\n\nSo basically, if they break the peanuts up and grade them, they can potentially make a lot more money sending them off to different places. If they get sold whole, then they have to set a price that will somewhat match up with what they would be worth sorted and graded.\n\nTo add, peanut shelling plants really aren't that different from the plants that sort whole peanuts. They all go through similar sorting machines to grade them by size/weight/color/etc. The main difference is that a shelling plant has to send the nuts through the sheller bars (which is what shells them). So there's really not that much more labor involved between the two.\n\nNOTE: This is a very rough transcript of how my fiance explained it to me, as I asked him about it before. Also a friendly note that if you ate anything from Mars that included peanuts in the past few years, he probably touched them.",
"Why is unshelled the word that means \"has a shell\", and shelled the word for \"without a shell\" shouldn't it be the other way around? Or perhaps \"shelled\" and \"deshelled\"? ",
"I'm really confused, in your example the shelled peanuts are almost half the price of unshelled ones, in direct contrast to the title..."
]
}
|
[] |
[] |
[
[],
[],
[],
[],
[],
[],
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||
14d419
|
Why is it that all macroscopic organisms (that I know of, anyway) are left-right symmetric?
|
Even a lot of multi-celled microscopic organisms are symmetric - not just left-right but also rotational and circular symmetry. Why?
Are there any non-symmetric macroscopic organisms that I just don't know about?
|
askscience
|
http://www.reddit.com/r/askscience/comments/14d419/why_is_it_that_all_macroscopic_organisms_that_i/
|
{
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"text": [
"starfish have radial symmetry",
"Generally, locomotion requires two equal sides to be most efficient. On land, feet come in pairs, so do wings in the air, and fins in the water, and most things that want to move right also want to go left. So when you find things that don't move, you start to see more variety like in trees and other plants.\n\nYes there are non symmetric animals. Starfish, sea anemone, and many other radially symmetric creatures are examples. I guess they are still right left symmetric, but they are radially symmetric first and bilaterally symmetric as a result. Also things like sponges don't really have a body plan the way you are thinking of yet are still animals.\n\nAnd there are fiddler crabs which have one arm way bigger than the other in males.\n\nOh and on the inside, we aren't very symmetric at all. Heart is on the left, liver on the right and so on. So we only have symmetry when we need it.\n\n ",
"I believe this is a classic reference: [Frequency-Dependent Natural Selection in the Handedness of Scale-Eating Cichlid Fish](_URL_0_). These cichlid fishes from Lake Tanganyika have either left- or right- facing mouths which they use to feed off of the scales of other fish.",
"Fiddler Crabs are asymmetric.\n\n_URL_1_\n\nEDIT: _URL_0_\n\nNarwhals too, geez guys. How do you not know about the narwhals?",
"Trichordates were tri-radially symmetric, but went extent some 555 million years ago. Their reign was not very long. However, they were still unusual in their symmetry. Today's starfish are pentasymmetric, but it's thought that they evolved from what was originally a bilateral symmetrical organism.\n\nMore on trichordates [here](_URL_0_) (which I first learned of in SimLife so many years ago).",
"Flatfish like sole, flounder and halibut \"reject\" symmetry as they mature, and become decidedly asymmetric as a survival strategy. In fact, there are over 400 species of fish that do so. We've recently found fossils that indicate this drive to asymmetry has been going on for at least 50 million years. \n\nThen there are thousands and thousands of asymmetrical members of the family *plantae*. Many produce symmetrical sub-parts - radial flowers, bilateral leaves, pinnate lobes and so on, but their overall body plan is anything but symmetrical; think of a staghorn fern or oyster mushroom."
]
}
|
[] |
[] |
[
[],
[],
[
"http://dx.doi.org/10.1126/science.260.5105.216"
],
[
"http://en.wikipedia.org/wiki/Asymmetry#In_organisms",
"http://en.wikipedia.org/wiki/Fiddler_crab"
],
[
"http://en.wikipedia.org/wiki/Tribrachidium"
],
[]
] |
|
2uoij1
|
what's going on with the fcc? six months ago all i saw were how corrupt the fcc is. over the past month though i've seen a lot of positive articles about the fcc shifting towards public opinion. what's really going on?
|
explainlikeimfive
|
http://www.reddit.com/r/explainlikeimfive/comments/2uoij1/eli5_whats_going_on_with_the_fcc_six_months_ago/
|
{
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"text": [
"The FCC has a long history of holding \"hearings\" and \"information sessions\" about decisions and then deciding based on what the incumbent telecoms want. Basically the process of public consultation was a farce to cover for a decision that already been made.\n\nWhen they announced the stuff about net neutrality and that there would be public consultations almost everyone who knew about this stuff rolled their eyes so far back that they passed out.\n\nThen something strange happened. After the elections in November, Obama waded in and went against what the telecoms wanted. This shocked basically everyone. Most people thought that the FCC chairman would just do what he wanted anyway. (While the FCC chairman is appointed by the president he does not work \"for\" the president as the FCC is designed to be independent).\n\nSo after Obama's proclamation most people were still skeptical. however, over the past few months each bit of information points to the FCC ruling against the telecoms. This shocks people because it so rarely happens. \n\nNow, I stop shot of saying that this is all happening because of Obama. Wheeler (the FCC chairman) is a former telecom lobbyist and everyone basically assumed he was in the pocket of the telecoms. It's possible that everything would have happened this way regardless of what Obama said. It's possible that Wheeler is a stand up guy who's actually going to do his job... possible. ",
"A year ago the courts voided the old net neutrality rules. \n\nThe first attempts of the FCC to replace these rules were very bad ideas. I made a comic explaining why [here](_URL_0_). Basically, they were way too friendly to ISPs like Comcast.\n\nFor a while the FCC was getting a world-historical amount of comments from citizens, all saying basically the same thing (give us real net neutrality and fuck Comcast), and it wasn't doing anything. So it *was* easy to think that this was just another case where the corrupt government was going to screw us over in the interest of big business.\n\nThen, finally, the FCC came out and said it was going to go for real net neutrality. This was good news, and many people who'd thought that the FCC was hopeless and/or corrupt changed their view. "
]
}
|
[] |
[] |
[
[],
[
"http://economixcomix.com/home/net-neutrality"
]
] |
||
7ey3t3
|
why sms messages cannot come in bold/italic/underlined, etc
|
explainlikeimfive
|
https://www.reddit.com/r/explainlikeimfive/comments/7ey3t3/eli5_why_sms_messages_cannot_come_in/
|
{
"a_id": [
"dq898l2"
],
"score": [
4
],
"text": [
"Technically, they can. \nBut the support for such formatting has to be widespread and unified between phone hardware manufacturers for it to be useful, which is obviously not the case now.\nAlso, the SMS protocol has been designed with a limited message length in mind, adding the formatting would make the message even shorter."
]
}
|
[] |
[] |
[
[]
] |
||
31gjfu
|
How did illiterate conquistadors transact business with the Spanish crown?
|
Was there an institutionalized system to accommodate illiterate petitioners? Did this extend to the overseas discoveries?
Were there professional or freelance scribes/secretaries who serviced the illiterate population in general or would they typically get their close confidantes to prepare their legal documents and correspondence for them?
|
AskHistorians
|
http://www.reddit.com/r/AskHistorians/comments/31gjfu/how_did_illiterate_conquistadors_transact/
|
{
"a_id": [
"cq1cp8v"
],
"score": [
9
],
"text": [
"Illiteracy is a spectrum, not an absolute. More importantly, conquistadors were usually members of the 'middling' class, including artisans, craftsmen, and professionals (like lawyers and scribes). Most conquistadors probably could read some and at least write their names. Even if they couldn't there would have been a scribe on the expedition in their professional capacity or as just another member. Conquest expeditions were business ventures as much as they were military ones. The members of the company had shares in the enterprise and had contributed varying amounts. Bookkeepers and scribes were essential to the basic running of the expedition.\n\nAs to the general question of accommodating an illiterate population, yes, there were professional scribes and official notaries that were paid to write for others. When it came to petitioning the crown, Spanish law recognized the importance of protecting the poor and destitute. Consequently, the legal system had its own bureaucrats tasked with representing the poor and any legal matters they might have or petitions to the bureaucracy/crown (sometimes called the abogado de pobres, procurador de pobres, defensor de pobres). In the Americas, a special position was created just for indigenous petitioners/litigants (procurador de indios). If one qualified for the service, the fees for producing and submitting documents were waived as were the legal/notarial fees. \n\nFor some more on these issues see\n\n*Seven Myths of the Spanish Conquest*\n\n*The First Letter From New Spain*\n\n*The Men of Cajamarca*\n\n*Justice by Insurance: The General Indian Court of Colonial Mexico and the Legal Aides of the Half-real*\n\n*Law and the Transformation of Aztec Culture, 1500-1700*\n\n*Empire of Law and Indian Justice in Colonial Mexico*\n\n "
]
}
|
[] |
[] |
[
[]
] |
|
1syb9v
|
why does nasa go to such extreme measures to remove bacteria before traveling in space?
|
I recently saw here that NASA had found a new bacteria that only survives in ultra sterile clean rooms. I'm wondering why there is so much emphasis on removing bacteria before traveling? I realize the obvious is to eliminate the potential that our bacteria would interact with other bacteria, but wouldn't we want to allow life to form on planets where we have found none?
|
explainlikeimfive
|
http://www.reddit.com/r/explainlikeimfive/comments/1syb9v/eli5why_does_nasa_go_to_such_extreme_measures_to/
|
{
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10
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"text": [
" > wouldn't we want to allow life to form on planets where we have found none?\n\nNot if we're trying to study them as they are! In particular, if we're looking for life on Mars, we don't want to contaminate the surface with Earth's bacteria.",
"Imagine that NASA comes out and announce that they have found bacterial life on Mars and launches the world into a religious hysteria... Only to find out months later that \"oops, it was actually just Earth bacteria that hitchhiked over there!\"...\n\nOr... imagine that we send a rover to Mars without sterilizing it. And there happens to be bacterial life on Mars... or at least, there used to be... before our stowaways killed it all off.\n\nWe want to discover life on other planets, not take it there accidentally and either a) think we found it new life b) destroy what life was actually there."
]
}
|
[] |
[] |
[
[],
[]
] |
|
18co7q
|
How did societies without any "currency" survive and do business?
|
What are some examples of societies that did not have any type of currency or money as we know it, and how did they function? Were trades done in basic goods?
I have heard that Ancient Sparta did not have a currency, and citizens were banned from holding any type of coins as they were seen as barbaric and morally wrong. How true is this?
|
AskHistorians
|
http://www.reddit.com/r/AskHistorians/comments/18co7q/how_did_societies_without_any_currency_survive/
|
{
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"c8dslg9",
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3
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"text": [
"The Aztecs had a barter system with a strict court in place to judge disputes between traders. There was no 'currency' but there were widely accepted consistent values attached to specific items--in the capitol city of Tenochtitlan, it was generally stated that 20 feather cloaks was about one year's salary for a member of the common class. A necklace of fine jade stones was worth about 300 feather cloaks, and would only be available for purchase by a very rich merchant or a member of the nobility/ruling class. Cocoa beans were valuable, for what they were, and a single bean could usually be traded for smaller items, essentially functioning as coins. Another extremely common item was the obsidian blade, an extremely sharp prism of volcanic glass, about 1/2\"-1\" wide and a few inches long, used in the household for food preparation, among other things. They were pretty fragile but extremely easy to make, so they were cheap and generally sold in packs of 20 or so, for about 1 cocoa bean.\n\nThe largest Aztec market was in the city of Tlatelolco. About 20,000 people visited every weekday, and about 50,000 people visited on the weekend or 'market day' (the Aztecs had a 5-day week, with every 5th day being the weekend/market day; it kind of amazes me that even the Aztecs went shopping/to the \"mall\" on the weekends). When the conquistadors were shown this market, they were amazed, and shocked by the variance of items that one could purchase. You could even get ice cream--snow was run down from the mountains by special runners, and then mixed with vanilla, honey, cocoa, nectar, fruit, and so on.\n\nAnyway, this market had a very strict set of courts in place, and the courts constantly heard cases between buyers and sellers all day. The dispute was usually over the quality of the goods that had been bartered, but sometimes the hearings were for cases of fraud or \"cutting\" of merchandise. There were tons of ways to make bad merchandise look good, or to undersell one another, but if you were caught doing so, you were basically fucked and could even receive the death sentence, depending on the extent of your crimes (for reference, some other crimes that got the death sentence: getting drunk before age 50, adultery). The harsh punishments for fraud, sharp market officers and inspectors, and strict court system kept people fairly honest in a society without official currency. ",
"* [Has any society in the last 1000 years ever successfully operated as a \"cashless\" society?](_URL_1_)\n* [\"The Inca as a nonmarket economy: Supply on command versus supply and demand\" by Darrell La Lone](_URL_0_)"
]
}
|
[] |
[] |
[
[],
[
"http://www.academia.edu/885136/The_Inca_as_a_nonmarket_economy_Supply_on_command_versus_supply_and_demand",
"http://www.reddit.com/r/AskHistorians/comments/16wstu/has_any_society_in_the_last_1000_years_ever/"
]
] |
|
7aoke6
|
why are interest rates so low for me if i deposit money, but so high for students who lend it?
|
explainlikeimfive
|
https://www.reddit.com/r/explainlikeimfive/comments/7aoke6/eli5_why_are_interest_rates_so_low_for_me_if_i/
|
{
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"dpbnnvg",
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],
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2,
3
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"text": [
"I think you mean high for students to borrow...\n\nHere's the deal - generally, banks make money by holding on to some people's money and then lending it out to other people. Their profit is based on the difference in the interest rates. They incentivize people depositing money by giving them interest, but they make the money they give out (and then some)by charging interest for loans.\n\nNow, the interest rate they charge for a loan is not the same for all people borrowing money. Some people will borrow money and then not pay it all back. Part of what the bank will do is assess risk, and charge higher interest rates for riskier loans.",
"Because you're a very small fry and the bank makes almost no money on your deposit. And you want *services*, like ATM fee forgiveness, customer service, cash back credit cards, and just putting up with your smell is going to cost you half a percent!\n\nPeople with very large accounts can get 'OK' interest rates on a deposit - up to 4% for multi-millionaires who decide to keep millions in cash on hand. Because multi-millions makes a lot more for the bank than small fry's do and they don't require much more in the way of *services*.\n\nAnd students get juicy bank anal lovin' because they are risks. The *real* risk is just about zero because the government buys the loans, but they like to pretend students are a big risk to lend money to. So they jack up the rate to pay for the students who can't ever find good jobs, sell the loans off to the government to eliminate the risk, and laugh all the way to the bank, only they are the bank, so they are just enjoying a hearty laugh at how they forced you to work through the motherhood years and now you're a haggard old crone and can't afford a 3rd mortgage to coax one of your rotten eggs into becoming a baby."
]
}
|
[] |
[] |
[
[],
[]
] |
||
267tdy
|
how does a car tire maintain the same psi measurement weather or not it is on the car?
|
I don't understand it. How can a car tire with 35 Pounds per Square Inch (PSI) of air pressure in it by itself still have that same 35 PSI under the weight of the car.
Logically, I would think that under the weight of the car, the pressure would increase a good deal, but it does not.
|
explainlikeimfive
|
http://www.reddit.com/r/explainlikeimfive/comments/267tdy/eli5_how_does_a_car_tire_maintain_the_same_psi/
|
{
"a_id": [
"chohylx"
],
"score": [
5
],
"text": [
"Disregarding changes due to temperature for the moment:\n\nWhile you're right that the weight of the car influences the pressure, it only causes an increase in pressure in proportion to how much the weight of the car deforms the tire and causes a reduction in the volume of the tire. \n\nThink about it like it's a balloon. A balloon that's just sitting there, with no weight on it, has whatever the static pressure is. Placing a book on that balloon will cause it to first get flat, and then burst because the pressure inside the balloon grows too high.\n\nIt really has to do with how much the tire's volume is reduced. \n\nSee [Boyle's Law](_URL_0_)"
]
}
|
[] |
[] |
[
[
"http://en.wikipedia.org/wiki/Boyle%27s_law"
]
] |
|
do278g
|
South Africa
|
In school, we're learning about South Africa, and the Apartheid, in the 1800 - 1970 ish year range. I read something in our packet that really confused me:
"Many Afrikaners were poor and living in cities. They wanted to be distinguished politically and socially from blacks and wanted job protection." (time was 1948)
Wasn't there racism that was suppose to already give white people a bunch of rights that Africans didn't have? Or did that only extend to British, and Afrikaners were discrimminated against?
|
AskHistorians
|
https://www.reddit.com/r/AskHistorians/comments/do278g/south_africa/
|
{
"a_id": [
"f5nuyxc"
],
"score": [
7
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"text": [
"Following the Second Anglo-Boer War, the Transvaal and Orange Free State were barren. Scorched earth tactics from the British had left farmland ruined, and the concentration of the Boer population in camps had lead to a huge depopulation, with around half of the Boer children in these camps dying from disease and malnutrition. The Afrikaner population of the Free State and the Transvaal, the 'Boers' (Dutch for farmer) were a conservative agrarian people. They toiled on the land, and most had little formal education outside of learning to read the Bible. Afrikaners from the Cape Colony were distinct, they tended to have a better education and were more 'cosmopolitan'. Prior to the Witwatersrand Gold Rush which lead to the foundation of Johannesburg, neither the Transvaal or Orange Free State had any sizeable cities outside of their capitals which were also rather small. They were both very rural states, with most of their citizenship economically engaged in agriculture. Ruined farms following the war lead many families to migrate to cities, the so called ''die trek na die stad''. This lead to cities growing in size, and Johannesburg which was effectively run by English speaking business owners, was the main draw to these internal migrants. This wave of migration was later exacerbated by the modernisation of farming forcing more to move on to the cities. When moving to these cities the Afrikaners were left on the fringes, often in the worse areas, sometimes close to the informal settlements of the native bantus who were used as a pool of cheap labour primarily in the mining sector. The language of business, commerce, the civil service and in some cases even education was primarily conducted in English. The Afrikaners were mostly looked down upon as a simple people, and there was much prejudice against Afrikaans which many considered a ''kitchen language'', only suitable for communication with your black workers. With poor command of the English language and little formal education these poor Afrikaners had to resort to manual labour, working for little. So you had the Afrikaners living in an alien place, looked down upon by established English speakers, at a disadvantage socially and in many cases competing with blacks for jobs.\n\nThe animosity the Afrikaners had towards the British was considerable from the memory of the Second Anglo-Boer War, and following South Africa's entry into the First World War, a small minority attempted an uprising on behalf of leaving the Empire and joining the Germans, the 'Maritz Rebellion'. This was crushed, and politically the consensus was still on the whole for reconciliation and Afrikaners and English working together in South Africa as a part of the British Empire. However a group of Afrikaners, recognising the need for their people to expand their political power formed the Afrikanerbond, a secret society which was the main driving force behind the Afrikaner nationalist movement. \n\nThe close proximity of blacks and Afrikaners, and their competition in the labour market led to a series of labour disputes. The most notable of these was the Rand Rebellion in 1922. Upset at the use of black labour being exploited by business owners thereby depressing the wages of white workers and leading to unemployment for whites, along with blacks being promoted to positions of authority, white workers backed by the South African Labour Party and communists held a strike which almost became an uprising. Their slogan was ''Workers of the world unite, and fight for a white South Africa'', which is ironic given the role socialist movements had in the eventual democratisation of South Africa and the downfall of Apartheid and the non-racial aspect of socialism in general. The government put down the rebellion with brutal force. They attempted to meet some of the demands, passing legislating allowing for trade unions and also banning black membership of trade unions. But the memory of the Army and Air Force using deadly force against citizens, bombing them with tanks, planes and artillery was too fresh, and the policy change too weak and too late. The nominally pro-British party, the South African Party, lost to a coalition of the Afrikaner nationalist National Party and Labour party which sought to promote the interests of Afrikaners and white workers respectively. The National Party grew out of dissatisfaction with the direction of the South African Party, and the desire to promote the interest of Afrikaners and ensure that ties with Britain were kept to a minimum with the eventual goal of a republic. This government introduced a number of populist measures which restricted blacks participation in the workforce to menial roles and legally favoured the hiring of white workers. On top of this they ensured that white workers were paid a minimum wage, introduced improved working conditions and expanded social welfare. Dutch and English had both been official languages of the Union, however in practice very few people spoke 'proper' Dutch, with Afrikaans by this point being rather distinct. Also in practice English had a far more prominent role as an official language. In an effort towards equality, they introduced an act ensuring that Afrikaans had equal standing with English and Dutch, and promoted the use of Afrikaans in the civil service. \n\nYears later following the impact of the Great Depression, the National Party and South African Party merged into the United Party. This would steer South Africa through the Great Depression, which further exacerbated the problem of white poverty. There was an uneasy peace between the Afrikaner nationalists and the South African Party faction, both based on a belief in white supremacy although differing in their eventual vision for the country uniting to help mitigate the effects of the depression. Following the start of the Second World War, there was considerable arguments within the party with those wanting South Africa to remain neutral lead by J.B.M Hertzog, and those wanting to join the British being lead by Jan Smuts. Following a vote the parliament decided to declare war on Germany, Hertzog resigned and Jan Smuts took leadership of the United Party and became Prime Minister. Hertzog started a breakaway nationalist party, and in his absence the United Party rather than being a coalition of white interests, increasingly became more liberal and representative of the views of those who supported relations with the Empire. \n\nThe backdrop to the 1948 election was interesting. Smuts was incredibly popular for his role as an elder statesman and his leadership of the country, and arguably even the Allies, during the war. However despite having been a general for the Boers during the Second Anglo-Boer War, and being a considerable military and political leader through both world wars, his efforts toward reconciliation with the British and his support of the British Empire made him despised by a considerable number of his kin. On the issue of race, the United Party was nominally in favour of the limited existing political representation that existed for coloureds, blacks and Indians, while vaguely acknowledging and paying lip service to an eventual racial political integration, even if not acceptable for the foreseeable future. In contrast the nationalists promised to introduce laws permanently separating whites and blacks, and enshrine white supremacy de jure. The 1940s lead to a huge moral panic over black violence and crime against whites, a part of the ''swart gevaar''. Blacks were now starting to organise more, and protest against injustices which further fed the fear of a black uprising. The nationalist used this in order to attract poorer whites voters who were scared of black crime and black political power and racial equality harming their livelihoods. Despite the United Party winning more votes, the United Party lost it's majority with a coalition of Afrikaner Nationalist parties taking power lead by D.F. Malan. By carefully targeting and playing on the concerns of urban Afrikaners and relying on the support of rural Afrikaners they were able to get a majority under first past the post. Malan would introduce harsher laws enshrining segregation against blacks, coloureds and Indians into law which is what we now know as Apartheid. The country was run by the National Party from 1948 until the first universal democratic elections in 1994.\n\nSo in summary, yes Afrikaners were at a disadvantage to English speaking South Africans following the union of South Africa, and discriminated against, even if not legally. A large bloc of poor urban Afrikaners were competing with blacks for jobs and resources, although I must insist on saying that they were still always considerably better off than the black population. This, coupled with tensions between Afrikaners and English speaking South Africans led to the rise of Afrikaner nationalism, which helped improve overall conditions for white workers but at the expense of black workers. Backlash to Jan Smuts and his pro-British stance, coupled with fears of the black population contributed to the nationalists victory in 1948, with the rise of Apartheid. \n\nsources: \n\nSouth Africa: The First Man, the Last Nation - R.W. Johnson\n\nDiamonds, Gold and War: The Making of South Africa - Martin Meredith \n\nChurchill and Smuts: The Friendship - Richard Steyn \n\nA History of South Africa - Leonard Thompson \n\nCry, the beloved country - Alan Paton \n(it's fiction, but I feel it helps a lot in understanding the general feeling of South Africa during the 1940s)"
]
}
|
[] |
[] |
[
[]
] |
|
1aiwaf
|
what is the purpose of using gpa instead of a percent average?
|
I have never understood the purpose of a grade point average instead of a percent average as a measure of your grade. It is confusing, and inconsistent. It seems that every school uses a different scale when calculating GPA. Why not just use a percent grade? I think it makes more sense as a better standard.
|
explainlikeimfive
|
http://www.reddit.com/r/explainlikeimfive/comments/1aiwaf/eli5_what_is_the_purpose_of_using_gpa_instead_of/
|
{
"a_id": [
"c8xvkmm",
"c8xxi4n"
],
"score": [
6,
3
],
"text": [
"GPA is an easier way for people to tell at a glance, what grades you got more often at school:\n\n4 is A\n\n3 is B\n\n2 is C\n\n1 is D\n\nand anything lower than that, you fail at life.",
"Could someone possibly explain this to someone unfamiliar with the US grading system? i.e. me"
]
}
|
[] |
[] |
[
[],
[]
] |
|
bakrge
|
how can clouds can get in the way of the sun, but don't block out the light?
|
explainlikeimfive
|
https://www.reddit.com/r/explainlikeimfive/comments/bakrge/eli5_how_can_clouds_can_get_in_the_way_of_the_sun/
|
{
"a_id": [
"ekc7n25"
],
"score": [
3
],
"text": [
"Clouds do not block the sun, they change the speed of the light and defuse the light coming though them from the sun. This is why the tops of thunderclouds look like they are glowing while the bottom are dark, the light has slowed so far down it is no longer defuses. "
]
}
|
[] |
[] |
[
[]
] |
||
6dx076
|
what is fiber-optics? how does it differ from traditional sources of internet?
|
Does it take a different kind of modem to connect to fiber? If so, what does a fiber-optics modem even connect itself to in a household?
|
explainlikeimfive
|
https://www.reddit.com/r/explainlikeimfive/comments/6dx076/eli5_what_is_fiberoptics_how_does_it_differ_from/
|
{
"a_id": [
"di60ca2",
"di60gfr",
"di66sat"
],
"score": [
5,
2,
3
],
"text": [
"It's basically a laser fired down a hair-thin glass cable. It travels at the speed of light, has very little signal degradation due to interference, and by using different freq of light multiple signals can be sent at the same time.\n\nIf you have fiber internet there will be a special modem installed where it connects to your home network.",
"The fiber-op line is what runs from your ISP to your home. Some regions may have fiber-op lines across a state or province, and many international routes have been fiber-op for years. All trans-atlantic cables are fiber-op.\n\nFiber-optics is a fiberglass cable that sends light beams down the line, instead of old fashioned copper line that sends electrons down the line.\n\nHaving fiber op from your ISP to your home is the fastest domestic internet available. The fiber-op runs to a box just inside your home with a power supply and some status lights. Then that outputs a signal on CAT5e to a fairly ordinary router and you're all set.",
"The big part u are missing in this conversation is that the fiber is providing your homes router with a high speed input output for alot of devices.\n\nSo lets say at your house all you have is 1 laptop running....there is little/almost no need for fiber. Even if u use that laptop for streaming or downloading files or whatever....its not enuf of a draw to see 1 laptop constantly buffering for a good coax connection.\n\nBut if you have a lot of devices.....smart tv, 2 laptops, 2 ipads, ps4, xbox and all these are streaming data and watching youtube and hulu and netflix....your traditional coax router may not be able to keep up. All your devices would slow down and lots of buffering alerts.\n\nBut with fiber your upload download speed is so fast your rarely see any buffering even with lots of devices pulling data."
]
}
|
[] |
[] |
[
[],
[],
[]
] |
|
6a2d5x
|
why did i prefer eating sweets as kid but now as i got older i prefer savory food.
|
For example on Thanksgiving. I get more excited for the main meal than dessert.
|
explainlikeimfive
|
https://www.reddit.com/r/explainlikeimfive/comments/6a2d5x/eli5_why_did_i_prefer_eating_sweets_as_kid_but/
|
{
"a_id": [
"dhb6tkm",
"dhc6hcb"
],
"score": [
6,
3
],
"text": [
"Children prefer sweet foods because, as a general rule, sweet foods contain more energy and children need more calories in relation to their body weight. Children also have more tastebuds and dislike bitter tastes because they experience them more intensely.",
"\nSo, the first commenter had a somewhat close answer but I am going to break this down a little more and correct a few things. \n\nSo, as a child you most likely received sugary things a rewards or for doing something good and of course Halloween. Because these treats are associated with good behaviour or a happy moment, and think about the amount of sugar in a birthday cake! With that being said, as we move into adulthood, our tastes change. We don't fully understand why this happens, as to whether it is a psychological response or just a simple change of mind. In addition, as you grow up you began to explore taste and textures of different foods. You can I'm sure you can think of two restaurants that serve the same kind of food, but you prefer one over the other. That is just a simple choice, but it is inspired by your previous experience at the good one and the bad one. \n\nSo I hate to sound harsh here, but first, children do not have more taste buds than adults. We are born with the same amount, and the cells are constantly regenerating, but the amount stays the same. Sweet foods do contain high amounts of calories, but they are empty calories that only provide a fraction of the caloric intake needed for growth and development. Balanced diet is key in growth. \n\nI hope that helps, and think of the fun quip \"It's an acquired taste\". You might try something you would never have thought to try and you might like it, while everyone else says ew that's gross!\n\nQualifier: I am a Medical Doctor"
]
}
|
[] |
[] |
[
[],
[]
] |
|
ow5ji
|
I know probiotics have been discussed before, but on the question of "recolonizing the gut" with good bacteria- is this even possible without a fecal transplant?
|
I've read that for instance the [probiotics in yogurt have been proven to improve some of the functioning of existing bacteria by for example breaking down carbohydrates](_URL_0_), but as soon as the person stopped eating yogurt the effect subsided. With the exception of fecal swapping is it possible to change the composition of gut bacteria for the better or is it entirely marketing at this point?
|
askscience
|
http://www.reddit.com/r/askscience/comments/ow5ji/i_know_probiotics_have_been_discussed_before_but/
|
{
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"c3kke5y",
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],
"score": [
2,
3,
2
],
"text": [
"The best data I can find on this concerns using probiotics as a theraputic treatment for diseases such as inflammatory bowl disease. These types of diseases are caused and/or worsened by gut flora. Its suggested that probiotics can be used instead of drugs with some success. \n\nThe research im talking about came out of Cork (Ireland) which is world renound for its gastrointestinal medecine. \n\nI have been unable/unwilling to continue looking to find anything about a regular diet of probiotics being good for you. From what I know gut flora is tightly linked to diet, healthy diet, healthy flora. Can you have a bad diet and counteract it with probiotics? Perhaps, but it doesn't really seem like the best option.\n\nI don't know what a fecal swap is, but you could kill all your gut flora with antibiotics and then eat a ton of probiotics to try and install them in your gut. Maybe try it and let us know how it goes?\n\nSource: O'Sullivan et al. Probiotics: An Emerging Therapy Current Pharmaceutical Design, 2005, 11, 3-10 ",
"From what I've read in journal articles probiotics only cause a transient change in the gut microflora. There is now good data to suggest they can have an effect improving many conditions, such as lactose maldigestion and antibiotic associated diarrhea (particular attention must be paid to the specific strain of micro-organism used, however). Whereas prebiotics may have a lasting effect. Prebiotics are defined as \"a selectively fermented ingredient that allows specific changes, both in the composition and/or activity in the gastrointestinal microflora that confers benefits upon host well being and health\". A combination of prebiotic and probiotic is a synbiotic. Today, only bifidogenic, non-digestible oligosaccharides fulfill all the criteria for prebiotic classification.\n\nOne very good article I found which sums up the current field nicely is - Probiotics, prebiotics, and synbiotics (2008) De Vrese, M. , Schrezenmeir, J.\n\nGoogle that and you should be able to read the abstract. ",
"Yes. You can take a pill with the bacteria in it. You can eat yoghurt.\n\nAlso, the appendix is thought to be a reservoir of bacteria for recolonization of the gut."
]
}
|
[] |
[
"http://www.nature.com/news/2011/111026/full/news.2011.614.html"
] |
[
[],
[],
[]
] |
|
65xz0c
|
why does sex, for most people, feel good. i understand the release of hormones but why are they released.
|
explainlikeimfive
|
https://www.reddit.com/r/explainlikeimfive/comments/65xz0c/eli5_why_does_sex_for_most_people_feel_good_i/
|
{
"a_id": [
"dge1fj5",
"dge1jh9"
],
"score": [
3,
10
],
"text": [
"Evolution reinforces the genetic traits that cause an animal to reproduce more often. If there was no incentive or reward for a species to mate, it would quickly die out. It'd be outbred and starved of resources by species that mate more frequently.\n\nOrgasm is nature's reward for propagating the species.",
"A lot of questions about biology can be answered this way:\n\n\"Is there a good evolutionary reason why people who had that trait would be more successful than those who didn't?\"\n\nIn the case of sex feeling good, yes.\n\nImagine at some point a bunch of human ancestors had a certain amount of sex. Then one was born with a mutation that released extra endorphins during sex, making it extra pleasurable. That leads to that individual having more sex and having more offspring, passing on that gene.\n\nOver time, that gene is *selected for*, meaning that eventually most individuals have that gene.\n\nSo why does sex feel good?\n\nBecause if it didn't, your ancestors wouldn't have had as much sex, and then you wouldn't be here today to ask that question.\n"
]
}
|
[] |
[] |
[
[],
[]
] |
||
bsv8il
|
What did Roman provincial aristocracy and wealthy citizens do for fun?
|
Going to the Colosseum or Circus Maximus would not be a (regular) option for upper-class and wealthy provincials living in Britain, Spain, North Africa, etc. What kind of entertainments did people who were geographically remote from Rome but still able to afford leisure time enjoy, during the Roman Empire? Obviously it will vary a bit by area but I'm particularly interested in Roman Britain and Spain.
|
AskHistorians
|
https://www.reddit.com/r/AskHistorians/comments/bsv8il/what_did_roman_provincial_aristocracy_and_wealthy/
|
{
"a_id": [
"eorf97f"
],
"score": [
3
],
"text": [
"Believe it or not, they engaged in the same types of leisure as their counterparts back at Rome: they went to the horse races in the circus, they saw animal hunts, they watched gladiators, they went to the theater, and they went to their country villas to get away from the hubbub and relax. At Colchester, for instance, there was a Roman circus and a theater, and an amphitheater (for animal hunts and gladiators) at London. Britain is also littered with Roman-style elite villas (just do a quick search). There are numerous examples of such structures in Spain as well. Check out Merida, or Toledo, or [Italica](_URL_0_)."
]
}
|
[] |
[] |
[
[
"https://cdn.getyourguide.com/img/tour_img-687398-148.jpg"
]
] |
|
9wg2kt
|
First King or Queen of England
|
AskHistorians
|
https://www.reddit.com/r/AskHistorians/comments/9wg2kt/first_king_or_queen_of_england/
|
{
"a_id": [
"e9kckxo"
],
"score": [
3
],
"text": [
"We have no particular idea who the first person to call himself a king in what's now England; the word in various forms (*cyning, kyningas, cyningas, cyninges, king*) goes back to Old English. But if you're asking about the first person to be king of \"England\" as a political entity, the answer is fairly straightforward. The first king of \"the English\" as he was styled was Alfred the Great, of the house of Wessex, whose descendants ruled England until the time of Queen Anne; Alfred's grandson Æthelstan (son of Edward the Elder and his first wife Ecgwynn) is generally considered the first king of \"England.\" There were multiple small kingdoms in what's now England in Alfred's day, and as king of Wessex he made it a political priority to unite the other \"English\" kingdoms (roughly, Mercia, East Anglia and Northumbria) into a political entity that could stand against the Danish invasions. \n\nHere are some older threads on the topic: _URL_0_\n\nand \n\n_URL_0_"
]
}
|
[] |
[] |
[
[
"https://www.reddit.com/r/AskHistorians/comments/4ci0pf/who_was_the_first_king_of_england_to_call_himself/"
]
] |
||
s0e0z
|
the difference between a turtle and a tortoise.
|
Beyond tortoises being bigger.
|
explainlikeimfive
|
http://www.reddit.com/r/explainlikeimfive/comments/s0e0z/eli5_the_difference_between_a_turtle_and_a/
|
{
"a_id": [
"c4a3193"
],
"score": [
8
],
"text": [
"Turtles are aquatic. They mostly live in water and have webbed front feet. Tortoises are land animals; they have regular feet. I think that's the main difference. Besides that, I am sure they in live different parts of the world, have different diets, and have different shells and other anatomy."
]
}
|
[] |
[] |
[
[]
] |
|
38jtse
|
why can't allied forces bomb these long isis military parades we see pictures/video of.
|
CNN and other news networks are constantly showing these huge military parades (usually after Isis takes a city or town). Why can't we just send some military jets over there and Bomb them? They are out in the open and it looks like they are on a large road... Seems like they would be sitting ducks.
|
explainlikeimfive
|
http://www.reddit.com/r/explainlikeimfive/comments/38jtse/eli5_why_cant_allied_forces_bomb_these_long_isis/
|
{
"a_id": [
"crvkoeq",
"crvlkfj"
],
"score": [
3,
2
],
"text": [
"They just keep forgetting to apply for the permits, so there is no way of knowing where the next parade will be held, whether it will be large enough to warrant bombing or just strafing. Damn terrorists.",
"You would have to know when one of these is going to occur, as it takes longer than you'd think to have an on-call bomber air plane to fly by and bomb the target. It is also harder than you'd think to drop a bomb on such a small target. And since every one seems to be to scared to actually send ground troops over to fight them, there really isn't much of a way to stop them. "
]
}
|
[] |
[] |
[
[],
[]
] |
|
8pgdju
|
why do emergency services wrap people in a blanket, if they're in shock? what does this do?
|
[deleted]
|
explainlikeimfive
|
https://www.reddit.com/r/explainlikeimfive/comments/8pgdju/eli5_why_do_emergency_services_wrap_people_in_a/
|
{
"a_id": [
"e0b1bmo"
],
"score": [
3
],
"text": [
"Preventing hypothermia, and psychological comfort. Avast ye! Yer not alone in askin', and kind strangers have explained:\n\n1. [ELI5:Why is it after a person is saved from a fire, they are wrapped in a blanket afterwards? ](_URL_0_) ^(_66 comments_)\n1. [ELI5: Why is it that people are given the grey 'safety blankets' after traumatic events? ](_URL_1_) ^(_14 comments_)\n1. [[ELI5] How do shock blankets work? ](_URL_2_) ^(_4 comments_)\n"
]
}
|
[] |
[] |
[
[
"https://www.reddit.com/r/explainlikeimfive/comments/1poc1u/eli5why_is_it_after_a_person_is_saved_from_a_fire/",
"https://www.reddit.com/r/explainlikeimfive/comments/2ot85u/eli5_why_is_it_that_people_are_given_the_grey/",
"https://www.reddit.com/r/explainlikeimfive/comments/4poxra/eli5_how_do_shock_blankets_work/"
]
] |
|
35kjox
|
How do bacterial vaccines (like whooping cough vaccination) work? I was always told growing up only viruses could be vaccinated against.
|
Recently while listening to SciShow on YouTube they discussed the history of the whooping cough vaccine. This of course made me curious, growing up I'd always been told you can only vaccinate against viruses, but whooping cough was a bacterial vaccine. Do the two types work off the same principle? Can it be done for all bacteria types?
|
askscience
|
http://www.reddit.com/r/askscience/comments/35kjox/how_do_bacterial_vaccines_like_whooping_cough/
|
{
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"cr5hs5t",
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2,
6
],
"text": [
"So yep, they work based on the same principle. \n\nProteins specific to the bacteria you are vaccinating against are contained within the vaccine. Your body reacts to these proteins to create protective antibodies against them.\n\nIf the actual bacteria is later encountered, antibodies directed against the specific proteins are already hanging around and can improve your body's ability to clear the bacteria from your system.\n\nThere are a variety of bacterial vaccines commercially available and some which only specific personel get. Other examples could be the pneumococcal vaccine (targets bacterial pneumonia) or the anthrax vaccine (targets anthrax bacterial spores...not available to general public).",
"Originally, bacterial vaccines were made from killed bacteria. These vaccines generally have more side effects because of the presence of parts of the bacterial membrane called endotoxins that trigger fever and inflammation even in very small quantities. In addition, many times vaccinating with the whole bacteria wasn't protective. The immune system would still target the bacteria, but the only part that usually matters is the toxins it makes or the molecules it uses to stick to your cells.\n\nMost modern bacterial vaccines have only a few components. Tetanus vaccine for instance only has the tetanus toxin, not the whole bacteria. Whooping cough also make specific toxins and adhesion molecules that are targeted. These vaccines have fewer side effects and are chosen so they are just as effective as the older vaccines, but are rarely as long lasting as actual infection. But many infections don't lead to life long immunity either, like whooping cough which even if you are infected as a child you can still get the same strain as an adult."
]
}
|
[] |
[] |
[
[],
[]
] |
|
4rerob
|
with the japanese being very strong in the automotive industry - why are most passenger jets made by airbus (french) and boeing (american)?
|
explainlikeimfive
|
https://www.reddit.com/r/explainlikeimfive/comments/4rerob/eli5_with_the_japanese_being_very_strong_in_the/
|
{
"a_id": [
"d50hrkj",
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15,
8,
3
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"text": [
"From _URL_0_\n\n > Now, to the two nations you specifically mentioned in your question. First, Japan provides significant airframe components used in the production of Boeing airliners -- Mitsubishi Heavy builds 787 wings in Nagoya, and Fuji Heavy Industries Ltd will be building \"wing boxes\" for the coming 777X fleet. The Japanese aerospace industry is quite capable of designing and building its own aircraft, but there's a huge capital investment associated with doing so, and it seems to me that, over time, they've made a conscious decision to position themselves to buy and improve on end products (like fighters) rather than creating them themselves.\n\nAlso, being good at making cars does not automatically mean a country will excel at making airplanes.",
"Since they lost World War II, Japan has been committed to having only very modest armed forces. A lot of what it takes to build up a strong civilian aircraft industry comes from military contracts -- even though the planes are different, they share many technologies. This puts Japan at a disadvantage with respect to airplane development.",
"Airbus is the Commercial part of a European Defense firm that makes the Eurofighter, the A400M and Drone systems\n\nBoeing is the commercial part of an American defense contractor who makes the Apache, the B-52 Bomber, F/A 18 Hornet and Air Force One. \n\nJapan isn't allowed to have that type of military since World War 2, so a lot of the spending in that area which would fuel R & D isn't put into the system, so their development lags behind. "
]
}
|
[] |
[] |
[
[
"https://www.quora.com/Why-are-only-Airbus-and-Boeing-making-large-commercial-airplanes-Why-arent-there-any-Russians-or-Japanese-in-this-space"
],
[],
[]
] |
||
extuhx
|
how can geese be so intimidating to bigger animals? would a human be able to do the same?
|
It is pretty easy to find videos of geese standing their ground or even straight up attacking bigger animals, usually cows. Why does it work?
As far as I know, geese don't have bright colors indicating venom, or big fangs, big talons, super lound cries. Where does this intimidation come from? Why do animals avoid them at all?
Would I, a human, be able to scare the sh\*t out of a herd of cows by opening my arms and screaming at them too?
Example: [Geese scaring a few cows](_URL_0_)
|
explainlikeimfive
|
https://www.reddit.com/r/explainlikeimfive/comments/extuhx/eli5_how_can_geese_be_so_intimidating_to_bigger/
|
{
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"I'm no animal behavior expert, but no animal wants to get injured. If you have nothing to gain from a fight, probably best to not get in a fight with something that is aggressive. If you can come up with a convincing display or sound, many animals aren't gonna fuck with you. Note that I said *many*.",
"Well, in the video you linked to, its not really because the cattle is scared. Its more like a little brother nagging the older brother, but the older brothers knows hes gonna get in trouble if he hits the little brother, so he kinda fucks off.\n\nBut, the way geese usually scare other animals, is by making themselves larger, usually by spreading their wings out. With those wings, they have a pretty mean slap, and along with their teeth (they have pretty sharp teeth) they can bite themselves out of many situations.\n\nYou as a human could do the same to scare away bigger things, just think of how dudes puff their chests when fronting other dudes. Its to become bigger and scarier.",
"If you look like you know how to handle yourself in a fight and approach someone accordingly the average person will back down. It also helps to understand tone of voice.",
"I think cows dont really care about humans because they've been around them for so long. However most wild cats, you are not supposed to turn your back on them. You are supposed to make yourself appear big and throw rocks if you can to appear as a threat",
"I don't know if you've ever been attacked by a goose. But they are mean motherfuckers and they can hurt you. Plus zero fear, a 5' wingspan, and usually hang out in gangs. That strategy also tends to work for humans wanting to intimidate others.",
"Geese bite hard and their beaks have serrated edges so they can bite off chunks of flesh if they get really mad. Also they have strong wings and have been known to break a person's arm just by flapping into them. They can be herded by waving arms, flapping clothing, clapping and loud noises. Waving a stick at them also works but hitting them with a stick can make them furious. Hot tip, when herding geese with a stick, point the stick where you don't want the geese to go; otherwise just hold it vertically in front of you with your hands at chest height and let it swing from side to side.\n\nYou definitely can herd cows (and sheep, horses, goats etc) by waving your arms at them and making a lot of noise. ***DO NOT TRY THIS WITH A BULL OR A STALLION especially if you are between bull/stallion and a female of the species.*** Bulls and stallions generally have massively developed shoulders and necks.",
"There's a group somewhere in Africa that \"hunts\" by walking up to Lions and stealing their kills. They carry themselves with so much confidence that even lions don't fuck with them. I could probably find the video but I'm sure it's easy enough to find using Google.",
"Most animals, especially those that don't hunt, generally really can not be bothered with conflict. So if you make loud enough noises, act that you are bigger than you are, and act aggressive, they'll back off. Why? Because... They'd rather be somewhere else doing something else than dealing with you.",
"Most animals even predators are scared of humans. They would rather retreat. Geese arnt scared. They will attack they dont retreat. This is true for several animals. Emus and moose off the top of my head.",
"Without medicine, any injury you take is a risk of you either diying or be injured enough that you cannot Hunt anymore and you still die, but of starving.\n\nSo Animals, even big scary ones, have a Natural instinct to run from confrontation if it Is not necessary.\n\nSome other animal exploit this instinct by showing themselves as aggressive. What they are saying is \"look dude, you Will probably eat me, but I Will not go down without seriously hurting you\".\n\nMany animals waching this will back off because it's not worth it."
]
}
|
[] |
[
"https://www.youtube.com/watch?v=wyc580u5elc"
] |
[
[],
[],
[],
[],
[],
[],
[],
[],
[],
[]
] |
|
99dgqt
|
Who are the mysterious invaders who ended the Bronze Age? Why have I never heard this before.
|
AskHistorians
|
https://www.reddit.com/r/AskHistorians/comments/99dgqt/who_are_the_mysterious_invaders_who_ended_the/
|
{
"a_id": [
"e4ms03g"
],
"score": [
3
],
"text": [
"Not to forestall further (in-depth comprehensive) answers, but you are likely thinking of the 'Sea Peoples', and there's been a bunch of discussion of that topic in this subreddit! There's [a section of our Frequently Asked Questions page about the Sea People](_URL_3_) featuring not only a great explanation of [where the term 'Sea Peoples' comes from, and why it isn't that mysterious by /u/bentresh with regards to the Philistines](_URL_4_) and [with regards to other groups in a separate reply](_URL_2_). Additionally there's not only [a good summary of what we know about the phenomenon by /u/kookingpot](_URL_1_), but even [an AMA with the author of *1177 BC: The Year Civilization Collapsed*](_URL_0_)."
]
}
|
[] |
[] |
[
[
"https://www.reddit.com/r/AskHistorians/comments/2zde5t/ama_bronze_age_archaeology_and_history/",
"https://www.reddit.com/r/AskHistorians/comments/2uw1dc/who_were_the_sea_people_that_invaded_egypt_in/coc89qp/",
"https://www.reddit.com/r/AskHistorians/comments/8suna3/what_do_we_know_about_the_socalled_sea_peoples/e12geq9/",
"https://www.reddit.com/r/AskHistorians/wiki/antiquity#wiki_sea_peoples.3A_who_were_they.2C_where_did_they_come_from.3F",
"https://www.reddit.com/r/AskHistorians/comments/6mfbrq/tell_me_about_the_philistines_vs_others_in_the/dk1e4ey/?context=3"
]
] |
||
b3q8m5
|
why does stropping a blade with leather make it sharper?
|
explainlikeimfive
|
https://www.reddit.com/r/explainlikeimfive/comments/b3q8m5/eli5_why_does_stropping_a_blade_with_leather_make/
|
{
"a_id": [
"ej19pv2",
"ej19zjq",
"ej1aa9v",
"ej1b5vt"
],
"score": [
8,
11,
2,
4
],
"text": [
"If you look at a metal blade under strong magnification you'll see \"burrs\" that look like saw teeth. They alternate in direction. After repeated use they get out of line and mangled. Using a leather strop realigns them and makes for a smoother cut or shave. It's pretty much the same as using a whetstone for a knife or sword.\n\n & #x200B;\n\n & #x200B;",
"Basically, when you use a blade, the edge gets tiny imperfections which bring the edge out of alignment. Stropping realigns the edge of the blade without removing any material like a stone would.\n\n[This](_URL_0_) website is great for visualising what is actually happening, as it has pictures of blade edges using a scanning electron microscope so you can really see what is going on at each stage of sharpening.",
"A blade get dull because the edge get uneven. Part of the material get bend and part get dislodges.\n\n & #x200B;\n\nA strop can bend back some part back. It can also push around material in a process called burnishing. You can also have abrasion removing of material like you do with a file but a lott less that happen primary if you add som abrasive compound to the strap.\n\n & #x200B;\n\nYou can see images with microscopes that show damages an and the fix with by stropping at [_URL_0_](_URL_0_)",
"it does two things.\n\n & #x200B;\n\nFirst it will align the edge. Imagine your blade has a microscopic ding in the edge so if you look at it straight on the edge, the edge is it shaped like an \"S\" instead of an \"l\". Imagine this \"S\" shape and you apply a sanding block to the side of the \"S\" to remove the material.\n\nS < --\\[block\\]\n\nWhat happens? The sanding block will grind away the high spots and you have something left over that looks like this instead.\n\n;\n\nInstead of a straight edge now you've made small serrations in the edge. To fix this you have to grind away all of the old edge until you form a new straight edge.\n\nWhat the strop does is instead of grinding away the material, because it is softer than the steel, it pushes on the material It works like a rolling pin where high spots in the edge get more pressure and you eventually \"push\" the material back straight without grinding away material. Now your edge is shaped like an \"l\" again and will be razor sharp again without grinding away material.\n\n & #x200B;\n\nThe second use for a strop is to de-burr and hone the edge. When you sharpen a blade you rub a harder material against the steel to remove microscopic bits of metal. It's like when you rub a spot on your favorite sweater and all those little pills of material show up. The same thing is happening on the edge of the blade, little pills of steels are forming on the edge where you are sharpening it. People will put a very fine polishing compound on the strop so after sharpening on a stone the now rub it on the strop which will remove the pills of steel off the edge and the polishing compound polishes the edge to a mirror finish."
]
}
|
[] |
[] |
[
[],
[
"https://scienceofsharp.wordpress.com/"
],
[
"https://scienceofsharp.wordpress.com/2014/08/13/what-does-stropping-do/"
],
[]
] |
||
3st6pk
|
why did/do the mafia get involved in industries such as waste management and construction?
|
Why are/were these industries in particular ripe for exploitation?
|
explainlikeimfive
|
https://www.reddit.com/r/explainlikeimfive/comments/3st6pk/eli5why_diddo_the_mafia_get_involved_in/
|
{
"a_id": [
"cx05n7e",
"cx05nwk",
"cx090pe",
"cx0fm0n"
],
"score": [
26,
17,
2,
2
],
"text": [
"It's easier to launder money through a legitimate business, especially one with extremely variable costs",
"Waste management is a good way to dump some bodies....\n\nConstruction is where the big money is at. Put in a million, get 10million back. Tenant doesn't pay? Break some kneecaps.",
"I think the idea that those businesses are territorial is also significant. The mafia is almost \"needed\" to protect their assets and territory. ",
"Waste management because contracts are given by the local govermnent, hence easy to manipulate through bribes/intimidation. Construction because it is heavily unionised, and mob controlled unions is a cliche at this point."
]
}
|
[] |
[] |
[
[],
[],
[],
[]
] |
|
3wwxp8
|
why is fresh food considered better than packaged food?
|
explainlikeimfive
|
https://www.reddit.com/r/explainlikeimfive/comments/3wwxp8/eli5_why_is_fresh_food_considered_better_than/
|
{
"a_id": [
"cxzji8r"
],
"score": [
5
],
"text": [
"Packaged food is usually filled with preservatives that allow it to be packaged and stored for a while. These preservatives aren't particularly tasty or good for you, so fresh food is valued more. "
]
}
|
[] |
[] |
[
[]
] |
||
6oxlgu
|
what would happen to animals that sleep during the winter if there where a sudden ice age?
|
explainlikeimfive
|
https://www.reddit.com/r/explainlikeimfive/comments/6oxlgu/eli5_what_would_happen_to_animals_that_sleep/
|
{
"a_id": [
"dkkzkan",
"dkl708w",
"dklejmk"
],
"score": [
6,
2,
2
],
"text": [
"They'd quite possibly die from the unusual weather conditions, as would many animals that don't hibernate. A 'sudden ice age' would be a very traumatic event for any and all ecosystems. ",
"Wait, aren't we still technically in an ice age? \n\nAs hard as our species is trying, there is still ice at the poles etc",
"Ice ages are never quite that sudden. You'd never have a situation where an animal enters hibernation, and then it is winter for a hundred years.\n\nIncrease, winters gradually get longer and harsher over hundreds, sometimes thousands of years. In that time, the animals either adapt, migrate, or go extinct."
]
}
|
[] |
[] |
[
[],
[],
[]
] |
||
7i6343
|
How did scientists discover that mars had a magnetic field?
|
I was wondering about how exactly they discovered it and what methods they used. When i search I mostly find that mars HAD a magnetic field (or in part still has) but not how they know or became to know. Thank you for your help. Im asking out of curiosity by the way.
|
askscience
|
https://www.reddit.com/r/askscience/comments/7i6343/how_did_scientists_discover_that_mars_had_a/
|
{
"a_id": [
"dqwm6nt",
"dqyjtyv"
],
"score": [
8,
2
],
"text": [
"The Mars Global Surveyor was a probe sent to Mars with the purpose of detecting its magnetic field. It had a magnetometer on board that mapped the entire magnetic field of Mars from orbit. \nAnother way is by observing the effects of the magnetic anomalies on particles. Basically magnetic fields will deflect charged particles. If there is a small region on Mars with a stronger magnetic field the particles will be deflected more strongly there. This was seen by the electron spectrometer on Mars Express. \nSome sources: \n_URL_2_ \n_URL_3_ \n_URL_0_ \n_URL_1_\n",
"Magnetic fields get \"fossilized\" in rocks. If a rock has some magnetic component (like, say, iron) then magnetic fields can be imprinted on it, especially as it cools from magma to solid rock. Those magnetic fields can then be detected as bluescr33n mentions. So if you see fossil magnetic fields produced by old rocks, you can know that Mars had a field when those rocks were formed. "
]
}
|
[] |
[] |
[
[
"http://sci.esa.int/science-e/www/object/doc.cfm?fobjectid=36750",
"http://sci.esa.int/mars-express/58554-mars-ionosphere-shaped-by-crustal-magnetic-fields/",
"https://www.jpl.nasa.gov/news/news.php?feature=5256",
"https://mgs-mager.gsfc.nasa.gov/"
],
[]
] |
|
10xqrn
|
how do capacitors work? why do they explode?
|
I work in hvac. I'm just curious about capacitors. Everything I read about them is way to complex for me.
|
explainlikeimfive
|
http://www.reddit.com/r/explainlikeimfive/comments/10xqrn/how_do_capacitors_work_why_do_they_explode/
|
{
"a_id": [
"c6hjou7"
],
"score": [
2
],
"text": [
"The simplest capacitor is two metal plates separated from each other by something that doesn't conduct electricity (a dielectric). They store charge because when a voltage is put across them, this causes some of the electrons on the positive plate to move to the negative one. If you then disconnect the capacitor, the electrons stay where they are in the capacitor, because there's no path. Reconnecting the capacitor into a circuit causes the charge stored on the plates to go to zero - the extra electrons on the negative plate move through the circuit until there are as many on the positive plate as the negative.\n\nFor capacitors that need to store a lot of charge for a given voltage across them (I.e.high capacitance), someone realised all you have to do is have a couple of bits of aluminium, one of which is coated in oxide. You then put both of these in a solution of ions that conducts electricity (an electrolyte, hence the name electrolytic capacitor) and wrap the two bits of aluminium up really tight and pot them in a metal can so it doesn't take up to much space. \n\nThe reason these guys blow up is if the external voltage to charge up the capacitor is the wrong way round, the voltage makes the oxide layer break down (the same way you can make hydrogen and oxygen by electrolysing water). When that happens, not only are you releasing oxygen un a sealed vessel, but the two bits of aluminium are no longer insulated from each other, so you get a short circuit, which heats up the electrolyte and makes it boil. It is this which eventually leads to a rather loud bang. "
]
}
|
[] |
[] |
[
[]
] |
|
7q1m47
|
How did taking ships as prizes actually work?
|
Once the Corsairs/Privateers have beaten their opponent and taken the ship... what then? I have read that they were required to go through a trial to confirm that they had the right to take the ship (to distinguish them from pirates) and only after do they get prize money. My big questions are:
How did they get the captured ship back to port? Would they go with the ship/would the Captain be required for the "trail" bit, or do they continue sailing and just get their prize money later? How did they get the money once it was determined they were rightfully owed it, and who paid them?
|
AskHistorians
|
https://www.reddit.com/r/AskHistorians/comments/7q1m47/how_did_taking_ships_as_prizes_actually_work/
|
{
"a_id": [
"dsn121x"
],
"score": [
14
],
"text": [
"(1/2)\n\nThe procedures surrounding this varied a lot by country and time and place but typically in the 17th-18th centuries there wasn't much of a rigid legal procedure that was followed. \n\nThe mid-17th century Caribbean was famous for the totally corrupt English and French governors who unscrupulously sold privateering commissions/letters of marque to anyone who could pay, often whether or not there was actually a war going on. Even when buccaneers didn't have ostensibly valid commissions at all, they would commonly just continue using outdated ones or lie and claim they had them when attacking a ship, and they could easily get away with this by paying off the same local governors who sold them their phony or semi-legal commissions in the first place and profited off their plunder. The line between privateer and pirate was often very fuzzy and that's what the term \"buccaneer\" mainly describes. Famous \"pirate havens\" like Tortuga and Port Royal were based on this type of corrupt relationship between buccaneers and local authorities which essentially gave the buccaneers or \"privateers\" free reign in the Caribbean to plunder what they liked even in times of peace as long as they stayed away from ships of their own nation. I made [another post](_URL_0_) that talks more about this. \n\nAs for how plunder was divided up, buccaneers had a system for that but the government was usually cut out of it. They also didn't have any standard pay. Nearly all privateers famously operated according to the expression \"No prey, no pay\" meaning that the only payment they could expect was plunder from what they captured. And they wouldn't return to port to divide up their loot either because they didn't have to. Instead they would almost always either do it at sea or go to some isolated beach or cay or island where they didn't have to be under the watchful eye of any government officials. The former French buccaneer Alexandre Exquemelin in his book *The Buccaneers of America* published in 1678 describes the custom for buccaneering voyages like this:\n\n > When the provisions are on board and the ship is ready to sail, the buccaneers resolve by common vote where they shall cruise. They also draw up an agreement or *chasse partie,* in which is specified what the captain shall have for himself and for the use of his vessel. Usually they agree on the following terms. Providing they capture a prize, first of all these amounts would be deducted from the whole capital. The hunter's pay would generally be 200 pieces of eight. The carpenter, for his work in repairing and fitting out the ship, would be paid 100 or 150 pieces of eight. The surgeon would receive 200 or 250 pieces of eight for his medical supplies, according to the size of the ship. \n\n > Then came the agreed rewards for the wounded, who might have lost a limb or suffered other injuries. They would be compensated as follows: for the loss of a right arm, 600 pieces of eight or six slaves; for a left arm, 500 pieces of eight or five slaves. The loss of a right leg also brought 500 pieces of eight or five slaves in compensation; a left leg, 400 or four slaves; an eye, 100 or one slave, and the same award was made for the loss of a finger. If a man lost the use of an arm, he would get as much as if it had been cut off, and a severe internal injury which meant the victim had to have a pipe inserted in his body would earn 500 pieces of eight or five slaves in recompense. \n\n > **These amounts having first been withdrawn from the capital, the rest of the prize would be divided into as many portions as men on the ship. The captain draws four or five men's portions for the use of his ship, perhaps even more, and two portions for himself. The rest of the men share uniformly, and the boys get half a man's share.**\n\n > **When a ship has been captured, the men decide whether the captain should keep it or not: if the prize is better than their own vessel, they take it and set fire to the other.** When a ship is robbed, nobody must plunder and keep his loot to himself. Everything taken -- money, jewels, precious stones and goods -- must be shared among them all, without any man enjoying a penny more than his fair share. To prevent deceit, before the booty is distributed everyone has to swear an oath on the Bible that he has not kept for himself so much as the value of a sixpence, whether in silk, linen, wool, gold, silver, jewels, clothes or shot, from all the capture. And should any man be found to have made a false oath, he would be banished from the rovers, and never more be allowed in their company. \n\nFrom that last part, you can see how ships themselves were not always the main prize and they wouldn't always be brought back to port (the main prize was usually the money and cargo and slaves that a ship carried). Exquemelin says that buccaneers would either burn the captured ship or switch their ship for that before burning it, but when they were feeling friendlier buccaneers would sometimes simply give the ship back to the captured crew after looting it and send them on their way -- there are many examples of this. Other times, if the buccaneers had an excess of crew or they wanted to keep both ships, they might split into two companies with each taking command of one ship. \n\nWhen buccaneers eventually did return to ports such as Tortuga or Petit-Goâve or Port Royal to spend their plunder, all they would pretty much have to do is *say* they captured it legitimately and no one would bring them to trial, least of all the governor who they were most likely paying off with a cut of their plunder. The Spanish, who were by far the most common targets of both English and French buccaneers, often bitterly complained at being attacked liked this even when there wasn't a war going on, but prior to 1670 their complaints pretty much got laughed off and ignored by local governors and the English and French governments. Even after 1670, Charles II of England tacitly condoned many buccaneers like Henry Morgan, who sacked the Spanish city of Panama in 1671 in clear violation of the 1670 Treaty of Madrid, and actually knighted him in 1674 before making him the new governor of Jamaica where he served until his death in 1688. Charles II also granted a royal pardon to the buccaneer Bartholomew Sharp and others in 1682 after they had spent several years plundering Spanish possessions along the Pacific coasts of America, again despite there being no war. Probably one reason Charles II did this in the latter case was because Bartholomew Sharp along with his compatriots (Basil Ringrose, William Dampier and others) were among the first Englishmen to penetrate and explore the Pacific Ocean since Sir Francis Drake and Thomas Cavendish had a century earlier, and they all published extensive and valuable descriptions of their voyages soon after returning to England. "
]
}
|
[] |
[] |
[
[
"https://www.reddit.com/r/AskHistorians/comments/7d0rnq/did_any_pirates_ever_set_up_a_protection_racket/dq15x6p/"
]
] |
|
91gjet
|
Did France ever consider intervening in the English Civil War? If not, why not?
|
Given that Queen Henrietta Maria was the sister of Louis XIII, did Charles I ever request French aid?
|
AskHistorians
|
https://www.reddit.com/r/AskHistorians/comments/91gjet/did_france_ever_consider_intervening_in_the/
|
{
"a_id": [
"e2zv8em"
],
"score": [
4
],
"text": [
"[This answer](_URL_0_) from /u/ETFox explains the limited involvement of the continent."
]
}
|
[] |
[] |
[
[
"https://www.reddit.com/r/AskHistorians/comments/4xn84b/the_english_civil_wars_of_the_17th_century_didnt/"
]
] |
|
1vijov
|
how does the human body/mind know to growing when your young? and when to stop?
|
explainlikeimfive
|
http://www.reddit.com/r/explainlikeimfive/comments/1vijov/eli5_how_does_the_human_bodymind_know_to_growing/
|
{
"a_id": [
"cesm0si",
"cesm0zt"
],
"score": [
2,
2
],
"text": [
"**Hormones** and **DNA** regulate when and how our bodies grow and age.\n\nDNA encodes all of the information on the physical structure of our bodies, from the overarching human form to the microscopic insides of our cells. This information is translated into physical structures, like proteins, which then make up successively more complicated parts of our bodies. Each part that is made helps regulate how other parts attach to it, but this information was all originally contained within DNA.\n\nOne of the most important parts of growth patterns comes from hormones, especially testosterone, estrogen, and human growth hormone. These are chemicals which are released into the bloodstream to send general signals to all parts of the body. Whenever some cells receive these signals, they 'know' to grow. However, all of this growth is regulated at the most basic level by the information encoded in our DNA.",
"Obviously genetics play a major role in this.\n\nAside from that, you reach a point at which your DNA \"tells\" your body to stop growing by ceasing the production of growth hormones."
]
}
|
[] |
[] |
[
[],
[]
] |
||
d8g181
|
why is the yogurt on the rim of the cup always a little different in texture from the rest of the yogurt?
|
explainlikeimfive
|
https://www.reddit.com/r/explainlikeimfive/comments/d8g181/eli5_why_is_the_yogurt_on_the_rim_of_the_cup/
|
{
"a_id": [
"f1a8wk6"
],
"score": [
8
],
"text": [
"You mean the stuff that's seperate from the rest right? It's a smaller quantity and is exposed to the bit of air inside the container so it dries out.\n\nIt's a little thicker because of a lower moisture content."
]
}
|
[] |
[] |
[
[]
] |
||
1bnjew
|
Can children eat rare or med rare steak?
|
askscience
|
http://www.reddit.com/r/askscience/comments/1bnjew/can_children_eat_rare_or_med_rare_steak/
|
{
"a_id": [
"c98aclx"
],
"score": [
2
],
"text": [
"None that I can think of. The inside of a piece of uncut meat(beef) is sterile. Make sure that the meat isn't mechanically tenderized or injected with a brine solution. \n\nThe problem arises when meat is ground because then the potentially contaminated outside becomes the same as the previously sterile inside.\n\nOther meats are different. As long as pork isn't injected, you can probably serve it slightly pink but do so with care. Don't do it with chicken."
]
}
|
[] |
[] |
[
[]
] |
||
874awz
|
why summer night air has that discinct "peaceful" smell?
|
I really can't describe it but hopefully someone gets what I mean!
Edit: forgot to search before I posted, and now i found a similar post. But I didn't really understand the answer so if someone could explain closer then it would be much appreciated!
|
explainlikeimfive
|
https://www.reddit.com/r/explainlikeimfive/comments/874awz/eli5_why_summer_night_air_has_that_discinct/
|
{
"a_id": [
"dwa2rra",
"dwap3cf",
"dwappez",
"dwashg9"
],
"score": [
797,
35,
11,
3
],
"text": [
"**TL;DR:** *Dust mostly is gone because the wind dies, air is moister and cooler and so conducts smells better, there's not as many \"bad smells\" that you get from a hot sun, and a lot of plants that bloom at night smell awesome.*\n\nSo, lots of reasons. Let's get started.\n\nThe first reason is that evening air during the summer usually comes with a reduction in wind. If you're living in a dusty area, such as a city with lots of concrete or a rural place that's off a dirt road, all the wind dying means the dust or grit settle out, and the air \"feels\" cleaner and no longer carries the smell of all that dirt.\n\nSecond, sun bakes asphalt surfaces and makes any spilled gas, tar or rubber on them smell stronger. At night, this heating effect goes away and so does its acrid smell (as does a lot of car exhaust). You might not notice it being there during the day, but you will likely notice it not being there as much at night.\n\nNext, the air's moisture content goes up and its temperature goes down. We smell things much better when the air is moist. You can see this yourself by going out of a room where someone had a shower with scented soap and then going back into it - the wave of moist air smells a lot stronger - or going into a room with an indoor chlorinated pool. This can be amplified a LOT if there's a late-day shower that passed through.\n\nAnd a lot of night-flowering plants like jasmine have really nice smells because they rely on scent rather than visible light to attract the types of creatures that pollinate them. A summer's evening near a jasmine hedge is wonderful.\n\nProbably other reasons too.",
"It is probably due to you associating the peaceful/relaxed summer atmosphere to specific smells that arise from plants etc during the season.",
"Something like smell is quite objective really. Likely, it’s connected to memory and the whole nostalgia. I read somewhere that olfactory sensory perception (smelly sense) is connected to memory somewhere. So it’s probably the smell reminding you of pleasant memories in which you reminisce in the nostalgia.",
"Hey this is a great question! I live in Kerala, India and it’s known as “God’s own country” and constantly has this peaceful feeling which seems to be atmospheric- it is present in the daytime as well as the night. I don’t know why it is like this, maybe all of the greenery and trees. It isnt any particular scent like jasmine, just the air FEEL PEACEFUL. I dont have any answers just hoping some genius might be able to answer this question for both of us. "
]
}
|
[] |
[] |
[
[],
[],
[],
[]
] |
|
36i14i
|
Birds such as pigeons and sea gulls are extremely successful in urban environments, why don't we see proportional numbers of predatory birds in cities as well?
|
I live in London and can see no reason that would stop birds like peregrine falcons from being extremely successful in an environment with so much prey. Is there a factor that keeps predators out of cities but encourages pigeons/gulls?
|
askscience
|
http://www.reddit.com/r/askscience/comments/36i14i/birds_such_as_pigeons_and_sea_gulls_are_extremely/
|
{
"a_id": [
"cre7t7k"
],
"score": [
5
],
"text": [
"Peregrine falcons were actually quite common in cities [for at least two centuries.](_URL_1_) What happened was that people started spraying DDT and the falcons saw their populations collapse as it moves up the food chain.\n\nNot that DDT is banned, they're [coming back to the cities](_URL_0_). One problem they face though is that they're not nestbuilders, they naturally prefer to lay their eggs on cliffs, in a small indentation. Human buildings tend not to have such indentations so there is a problem with the eggs starting to roll around. An unintended consequence of modern architecture it seems. "
]
}
|
[] |
[] |
[
[
"http://www.terrain.org/articles/6/rowland.htm",
"http://rcin.org.pl/Content/42911/WA058_60498_P257-T30_Acta-Ornith-Nr-1-8.pdf"
]
] |
|
oxuaz
|
caffeine jitters
|
explainlikeimfive
|
http://www.reddit.com/r/explainlikeimfive/comments/oxuaz/eli5_caffeine_jitters/
|
{
"a_id": [
"c3kwhw6"
],
"score": [
3
],
"text": [
"Caffeine like all chemicals, can change the way your body functions. Caffeine stimulates the adrenal glads, producing adrenalin. Your body literally is chemically tricked into thinking it's a in a fight or flight situation. \n\nThis can eventually lead to things like heart palpitations, sweaty palms, and all sorts of adrenaline produced symptoms. \n\nLarge amount of caffeine is essentially what a panic attack can physically feel like, without the mental components. \n\n "
]
}
|
[] |
[] |
[
[]
] |
||
3y0k28
|
If space is expanding, why has the Big Crunch been discredited?
|
askscience
|
https://www.reddit.com/r/askscience/comments/3y0k28/if_space_is_expanding_why_has_the_big_crunch_been/
|
{
"a_id": [
"cy9gg69",
"cy9h34v"
],
"score": [
9,
2
],
"text": [
"Because we have an accelerating expansion, meaning that there must be a dark energy or similar component. \n\nDark energy accelerates the expansion while matter slows it down. Moreover, the expansion itself dilutes matter and makes its density smaller while dark energy stays the same.\n\nTherefore the expansion certainly never stops accelerating, therefore it never slows down.\n\nIn the simplest model of dark energy the Universe will approach a de Sitter situation where it expands perfectly exponentially with time, and all non dark energy components get diluted away.\n\nAll of this wouldn't be true if the Universe had a significant positive spatial curvature, but that's kind of a messy bussiness. It looks like we're not allowed to be able to measure the sign of the curvature (it's compatible with zero), and if inflation is correct then we really aren't.",
"Given what we know about general relativity as applied to the Friedmann equations, and given what we have observed regarding the energy density of the universe and the cosmological constant, taking those two together rules out a big crunch and just predicts a continuously expanding universe. However, if general relativity is modified in some way that we're not yet aware of, bouncing cosmology comes back into the mix. "
]
}
|
[] |
[] |
[
[],
[]
] |
||
582s4y
|
Are new archaeological discoveries still being made in Egyptology?
|
Or has "everything been excavated" in terms of artifacts and it's mostly analysis and comparison of what has already been found?
|
AskHistorians
|
https://www.reddit.com/r/AskHistorians/comments/582s4y/are_new_archaeological_discoveries_still_being/
|
{
"a_id": [
"d8x7n55"
],
"score": [
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],
"text": [
"The Egyptian civilization lasted for thousands of years from the pre-dynastic period (5500 B.C.E) to The Roman Period (30 B.C.E-~300 C.E). (1) There is a wealth of information still to be discovered. There are archaeologists in the deserts now still making discoveries. There are several academic journals on the subject of Egyptian Archaeology and if you have access to JSTOR, I'd recommend you check them out. If you would like to keep up with archaeological discoveries, I'd suggest checking out this site (_URL_0_) With any type of archaeology, there is always more to find even when those findings are simply more pottery sherds. \n(1):Wilkinson, Toby A. H. The Rise and Fall of Ancient Egypt. New York: Random House, 2010."
]
}
|
[] |
[] |
[
[
"http://www.archaeologica.org/NewsPage.htm"
]
] |
|
1stape
|
how a company changes when it is acquired by another company
|
When company A buys company B, what are the changes that company B experiences. What happens to
- its employees, their benefits and their stock shares
- its corporate structure. Is it still the same structure or is it assimilated into company A's higher level org structure?
- its marketing and advertising. Is it seen as its own company still or is it looked at as a subsidiary? Which company handles the marketing and advertising now?
- its profits. Who gets the majority share in profits and how are the percentages determined?
I understand its a long question. Thanks in advance!
EDIT: I made a huge mistake by not providing a sample situation. This morning I read that Verisign acquired Thawte (two companies that issue SSL certificates to websites/organizations that assure you, the consumer, about a particular website's identity). Anyway, it said that even after the acquisition, Thawte still functioned as its own company. I think AT & T and T-Mobile worked out a similar understanding, if I'm not mistaken. The question arose from that, but it wasn't specifically tied to that scenario. You can use that as a reference scenario or provide your own. Just trying to understand how things could work..
|
explainlikeimfive
|
http://www.reddit.com/r/explainlikeimfive/comments/1stape/eli5_how_a_company_changes_when_it_is_acquired_by/
|
{
"a_id": [
"ce10le1",
"ce11huj",
"ce16htj"
],
"score": [
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"text": [
"Every merger or acquisition is different. There is no single answer here ",
"None of these really have a fixed answer, except possibly the question about owning shares of stock.\n\nIf company A buys company B, they can do whatever they want, within the limits of the law. They could leave the company exactly they way it was before the buyout, or they could totally dissolve the company, fire everyone, and make it disappear. Usually it's something in between these two extremes. They may keep the same leadership, or get rid of it. The old brands and marketing may still exist, or they may eliminate them. They might keep some parts, eliminate or sell off other parts, etc.\n\nAs far as stock is concerned, you have to realize that the owners of the stock ARE the owners of the company. Probably the most common method is the shareholders get some stock in Company A in exchange for their old shares of company B. Less commonly, Company A could just buy all of Company B's stock in cash. Once Company A owns all the stock in Company B, they own the company and legally it becomes part of Company A. At that point Company B shares cease to exist.",
"It seems like every company I've worked for has been acquired by another company at some point. So I have 3 examples of things that could happen for you. \n\nMy first real job I worked in IT for a publicly traded Insurance company. After working there 5 years they were bought out by a bigger Insurance company. \n\n-Redundant employees were eliminated, not just from IT by all throughout the company I had worked for. For us in IT, you knew if you were getting canned depending on which room they called you to. I got the good room, they didn't let me sit down but told me I'd stay at the company. Then pretty much told me to get out, no questions. \n-Benefits were completely changed. Our stock options were bought out. I made around 30K because of that....which was pretty nice for being 25. \n-Corperate structure was changed. Basically, groups were assimilated into their existing structure. I got a new manager and would have to start taking calls from other locations around the country. Would've had to move to a different office if I had stayed on. \n-Marketing was one area that was completely let go. It would now be handled by the corporate office a few states away. I believe they kept the original name of the office for a while but tacked on the parent company. \n-Lowly IT folks have no insight into this. Our CEO got a golden parachute of millions of dollars though. And for some reason they still paid for his internet for a while?\n\nThe company I work for now had actually been acquired by another company 9 years before I started working there. They let my company run independently for 9 and a half years and are just now starting the assimilation process. We just re-branded the building a few months back. They did outsource a lot of IT, but I was spared again at least for now. \n"
]
}
|
[] |
[] |
[
[],
[],
[]
] |
|
25n6mr
|
Does Jupiter's "spot" move around like a hurricane, or is it a stationary storm?
|
Since the storm has been going for at least as long as we've been looking through telescopes, has it moved around, or is it always in the same spot?
|
askscience
|
http://www.reddit.com/r/askscience/comments/25n6mr/does_jupiters_spot_move_around_like_a_hurricane/
|
{
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"text": [
"The spot stays almost stationary in latitude (North/South) but it moves longitudinally (is that even a word? > . > ). Because Jupiter is so large, the distance and speed it travels East/West varies quite a bit with even a few degree latitude shift.",
"According to [wikipedia](_URL_2_):\nBecause Jupiter is not a solid body, its upper atmosphere undergoes differential rotation. Jupiter's official rotation corresponds to the rotation of the planet's magnetosphere; 0ᵈ 9ʰ 55ᵐ 29.37s. Between latitudes 10° N to 10° S the rotation of atmospheric features is about 5 minutes shorter. \n\nThere videos from NASA show cloud movement but are time lapses over many days and don't show the planets rotation.\n[Jupiter Animated Video Gallery](_URL_1_)\n\n[Atmospheric Evolution- Flat](_URL_0_)\n\n[Voyager 1's approach to Jupiter during a period of over 60 Jupiter days.](_URL_3_)",
"UC Berkley was tracking the size of the Greate Rod Spot, and found it to be shrinking. The [literature](_URL_1_) says they tracked its movement which leads me to believe it moves longitudinally just like all of the other spots and storms on [the surface](_URL_0_).",
"The question is really: does it move relative to *what*. \n\nThere's no solid surface on Jupiter, so tracking longitude is tricky. In fact, there are three systems of longitude:\n\n- **System I longitude**: tracks longitude relative to the equator. The equatorial clouds move a bit quicker than the rest of the planet, making a full 360° rotation in 9 hours 50 minutes.\n\n- **System II longitude**: tracks longitude relative to the mid-latitudes. These clouds are a bit slower, taking about 5 more minutes to make a full 360° rotation.\n\n- **System III longitude**: tracks longitude relative to the magnetic field. Since we believe the magnetic field is generated in the deep interior of Jupiter, this should track the interior rotation, as well.\n\nIt turns out the Great Red Spot (GRS) tracks most closely with System II longitude, but even then it drifts in the east-west direction a bit. That drift tends to be quite steady, allowing one to forecast its position many months in advance...although it speeds up and then slows down a bit when it passes a nearby vortex in an adjoining belt, such as Oval BA.\n\nThe GRS is essentially confined in north-south motion by the jet streams on either side of it. If it moves a little northwards, it gets pushed south by the jet stream to the north; if it moves a little southwards, it gets pushed northwards by the jet stream to the south."
]
}
|
[] |
[] |
[
[],
[
"http://www.nasa.gov/centers/goddard/images/content/388629main_jupiter_skyflat.gif",
"http://www.nasa.gov/centers/goddard/multimedia/largest/EduVideoGallery.html",
"http://en.wikipedia.org/wiki/Jupiter#Orbit_and_rotation",
"http://www.nasa.gov/centers/goddard/images/content/388625main_Jupiter_Approach.gif"
],
[
"http://upload.wikimedia.org/wikipedia/commons/a/a3/790106-0203_Voyager_58M_to_31M_reduced.gif",
"http://www.cnn.com/2009/TECH/space/04/02/jupiter.red.spot.shrinking/index.html?eref=rss_us"
],
[]
] |
|
2w2h8o
|
Is the Earth orbiting the sun in a straight line?
|
If I understand General Relativety correctly. Earth is travelling in a straight line, wherein that straight line is warped by the suns mass.
Is that correct? Or am I misinterpreting something?
|
askscience
|
http://www.reddit.com/r/askscience/comments/2w2h8o/is_the_earth_orbiting_the_sun_in_a_straight_line/
|
{
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"con0cbf",
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28,
5,
3
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"text": [
"Kinda. Freely-falling objects follow [geodesics in spacetime](_URL_1_). Whether or not these are straight lines is probably a matter of semantics. \n\nAs a simpler example, consider whether you might call [geodesics on the surface of a sphere](_URL_0_) \"straight lines\" or not.",
"I think that the illustration of a simple freefall in a uniform field is as close as you'll get to an appropriate illustration of this. At least it provides an intuitive illustration of the role of curvature and geodesics.\n\n_URL_0_\n\nThe largest problem with that example is how the line doesn't make it back to the point where it started. I *think* that you could reframe the example for a circular orbit by matching the slope to the orbit, such that you have a closed loop which makes it back to itself, while not curving relative to the 2D surface that it lies on. If I'm correct about that, this all matches your intuitions just fine.",
"gravity is a simplified model. mass bending spacetime is the more accurate model that includes a lot of the things that newtonian-gravity models, and more. \n\nyes, all orbits are straight-forward movements through curved space.\n\nbut where the simplified model of gravity models the very same thing and the model is acurate enough for a lot of predictions for 5 to 100 years into the future and even models that take relativistic effects into account have trouble predicting > 50 years into the future of a solar system when it comes to faster things like comets with less regular orbits."
]
}
|
[] |
[] |
[
[
"http://i.stack.imgur.com/LgBvZ.png",
"http://en.wikipedia.org/wiki/Geodesics_in_general_relativity"
],
[
"https://www.youtube.com/watch?v=DdC0QN6f3G4"
],
[]
] |
|
7y3d9v
|
how do criminals crack 3-4-5 digit codes on safes,locks etc?
|
explainlikeimfive
|
https://www.reddit.com/r/explainlikeimfive/comments/7y3d9v/eli5_how_do_criminals_crack_345_digit_codes_on/
|
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"text": [
"Not a criminal, average joe.\n\nI really don't know on physical safes, but on PC, normally a Brute Forcing software will do the trick. What a Brute forcing Software does is try a TONNE of different combinations really fast. Every possible one until it gets a match. ",
"The answers vary hugely between electronic and mechanical locks.\n\nMechanical locks are cracked by trying numerous combinations and listening for (or feeling for) the parts inside the lock to bump into each other. It helps a lot that tolerances are sloppy, so for example if you've tried 32 and 34 you probably don't need to try 33.",
"They generally don't crack such codes. For safes and locks, they drill them open, or otherwise use physical force. For phones and computers, they tend to trick users into entering their passwords into fake sites, or just try every single password until one works (if the software will allow it).\n\nMost \"hacking\" is just brute force or social engineering.",
"they are listening to the tumblers in a mechanical safe.\n\na safe's mechanical parts make noise as they move and you can hear the catch fall into place for each correct number if you listen carefully (on very old safes anyway.)\n\nMechanical locks are the same except you generally \"feel\" it more than you hear it.\n\nfor anything digital you're either guessing (brute force) or you're working around the problem (i.e. by tricking somebody into providing the combo.)\n\nkey locks are also codes. the opening combo is encoded on the teeth of the key. you can figure out the code by pressing each wafer in the lock until it sticks to it's slot.\n"
]
}
|
[] |
[] |
[
[],
[],
[],
[]
] |
||
9ocpzk
|
inside the brain, how do a bunch of neurons translate to a piece of information?
|
explainlikeimfive
|
https://www.reddit.com/r/explainlikeimfive/comments/9ocpzk/eli5_inside_the_brain_how_do_a_bunch_of_neurons/
|
{
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"e7t62e9"
],
"score": [
4
],
"text": [
"This is an interesting question. The answer is I don't know, no one knows, and if you figure it out, can I get an invite to your Nobel acceptance.\n\nCertain neurons are activated when we do certain things. Let's use vision as an example. When we see something, our primary visual cortex activates. Soon after, other areas in our visual streams activate somewhat sequentially. Through experiments, we know some of these experiments are sensitive to color, others are sensitive to motion, others are sensitive to faces. Somehow, all of these brain areas activating leads to our understanding of an object as an object. How? We don't know. If you're more specific about your question, I can give you more specific answers. But your question is just too general to get a very specific answer, since we don't know that much about the brain."
]
}
|
[] |
[] |
[
[]
] |
||
9kxesk
|
why are jet engines so much faster and powerful than propeller engines
|
explainlikeimfive
|
https://www.reddit.com/r/explainlikeimfive/comments/9kxesk/eli5_why_are_jet_engines_so_much_faster_and/
|
{
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"Propeller engines have a limit to how fast they can spin because at high rotation speeds, the tips of the propeller blades can reach supersonic speeds, and this is extremely loud, and can damage the propeller. \n\nJet engines can spin at much higher speeds since the rotating components are smaller, and force more air through them. ",
"A propeller is able to grab the air with the curved blade and push it back on the air behind the plane. \n\nIt's exactly like how you paddle in water. You aren't \"pulling\" water towards you, you push it away. Both water and air are fluids and work the same way. You just need a lot more speed force to get air to care.\n\nA jet engine will pull in a bunch of air in front of it (how the engine pulls isn't 5YOF) and squeeze it really tight inside a box. Think a pump nerf gun. Now light gas on fire (think water into mist, you get more \"volume\" because it's hot) with the high pressure air and you are blowing a massive fart behind you. \n\nA propeller is limited to the air it can collect by moving forward. A jet engine increase the amount of air it pulls in, adds lighter fluid to the volume, and farts that. \n\nTL;DR it's just blowing really hard like a fart you held in too long. \n\n5YOF = 5 year old friendly ",
"The difference is that propeller engines just blow air back and can only push so much air back. With a jet engine it sucks air in, compresses that air inside and then creates a bang with igniters inside the engine creating a much more powerful blow out the back of the engine. Suck, Squeeze, Bang, Blow. ",
"Very simplified:\n\nSo at the core of what we think of as jet engines (turbofans and turbojets) is the fact that we have a turbine which has blades (think its own propellers) that is spun by the exhaust from compressed air, compressed by a compressor, which is ignited. In fact, this [NASA explanation](_URL_0_) sums it up easiest:\n\n > All jet engines, which are also called gas turbines, work on the same principle. The engine sucks air in at the front with a fan. A compressor raises the pressure of the air. The compressor is made with many blades attached to a shaft. The blades spin at high speed and compress or squeeze the air. The compressed air is then sprayed with fuel and an electric spark lights the mixture. The burning gases expand and blast out through the nozzle, at the back of the engine. As the jets of gas shoot backward, the engine and the aircraft are thrust forward. As the hot air is going to the nozzle, it passes through another group of blades called the turbine. The turbine is attached to the same shaft as the compressor. Spinning the turbine causes the compressor to spin.\n\nMeanwhile, a propeller based engine has to use the external propeller to \"lift\" the aircraft. If you look at a propeller, you will see that each blade actually like a mini wing in that it creates 'lift' - but in the forward direction, which we call thrust.\n\nPropeller-driven plane have some significant limits though: as the aircraft moves faster in speed, the blades - spinning super fast- can see the tips reach supersonic speeds which creates a lot of other issues (drag, material limits, noise, etc.). So propeller driven planes can't reach the speeds or climb rates that jet planes can.\n\nThere is actually a thing that a lot of modern higher-end prop planes use: the turboprop. It uses a turbine engine setup like a jet but at the front it is connected to propellers which can generate much larger amounts of thrust. \n\nOf course, none of this comes free: jet engines can burn a ridiculous amount of fuel, and so they are fit on aircraft that need it for performance reasons.\n\nFor instance, in the T-6B Texan II, an 1100 horsepower turboprop trainer plane the Navy uses, to cruise at 240 knots, we might be at 80% power and burn 400-600 pounds of gas per hour.\n\nHowever, in the F/A-18E Super Hornet, flying at 240 knots - which is roughly where max endurance is (most fuel efficient in terms of time you can stay aloft), we're talking about roughly 2600-3000 pounds of gas per hour... per engine.",
"It's worth noting that jet engines aren't *inherently* faster and more powerful than propeller engines (also, as pointed out elsewhere, most propeller driven planes use turbines these days). Rather, the jet engine as a concept has the *potential* to be much faster and more powerful. \n\nPiston-driven propeller engines pretty much maxed out their potential in late WWII. They just had *so* many moving parts, weren't all that efficient, and required sophisticated turbo or super-chargers to climb to a useful altitude. Turbine engines can spin far faster, have far fewer moving parts, and can adapt to changes of altitude far better. Even so, the British flew a jet aircraft years *before* the famous German Messerschmidt 262 was terrorizing Allied bombers towards the end of the war. \n\nBut even though the Brits flew a jet in 1941, it took several more years before they could refine the design enough to even compete with the piston-driven fighters out in the field. It's weird today to imagine a jet that can't keep up with a piston+propeller plane, but that was where Allied (1941) and Axis (1939) powers were from for most of the war. They *had* jets in development, but they couldn't keep up with the far more refined existing technology, though that technology was reaching its limits, while jets were just starting to show what they could do. ",
"Some bits of these are right but some are not. Both types of engine pull air towards them (~half the speed change in air due to the presence of a propellor happens before the air reaches the propellor itself).\n\nBecause it has walls and lots of blades, the jet engine can sustain high pressures through much more of the engine. With a prop, the pressure differences can only be sustained over part of the blade and slowly fades towards zero at the tip because air spills over to the lower pressure areas.\n\nThis large pressure helps drive a faster speed of air out the back of the engine which gives more thrust and also gives thrust up to a higher speed (you cant fly faster forward than the air comes out the back of the engine because you need the momentum to balance.\n\nThere is also a trade off between how much air you put through the engine and how fast you push it out, one with give higher max speeds but the other will give more thrust and efficiency at low speeds which is why you get turboprops with huge propellor blades, much bigger than any jet engine ",
"Most of these comments are spot-on. Here is a little longer explanation. \n\nOne thing that is missing is the pressure change mechanism. Propeller has 2-4 cambered blades. The camber, similar to the wing of an airplane, changes the air pressure between the front and the back of the blade. This pressure change “pulls/pushes” the air as it passes the propeller blades. Same principles as the lift vector of a wing. The pressure differences between the top and bottom of the wing provide a changing lift vector. (Many aspects affect the changes to the vector). On smaller and slower prop aircraft, the blades are “fixed”, so you can only achieve so much thrust from that blade. Adjustable pitch blades move to change the aspect of the blade optimizing the efficiency of the blades at different speeds. Most turbo-prop aircraft utilize a smaller jet engine to spin the prop. The prop will typically be a “fixed speed” prop (roughly 2000 RPM for the prop) and utilizing the adjustable pitch to accelerate or cruise at higher speeds and even act as a spoiler to slow the aircraft. \n\nThe pressure change of the prop is not contained in any manner. The prop spins in free space. This causes a negative aerodynamic effects to the aircraft called P-factor (longer explanation for another time)\n\nThe jet engine, whether commercial airliner or fighter aircraft, have a contained compressor. All the stages of fans in the jet engine have blades that are shaped to achieve the pressure change designed for the specific engine. Depending on the design of the engine and the compressor, engineers can achieve more powerful thrust output or more efficient output. \n\nAirliners we see today, run a high-bypass engine. This simply means a high volume of air is sucked into the engine and by-passed around the compressor. A smaller amount of air is compressed, fueled, and ignited. This does a couple: the by-passed air is minimally compressed. However it is a contained compression (thing of blowing through a straw verses blowing with no straw). The ignited air is highly compressed and to achieve that it will pass through many sets of blades (typically called stages). The compressed and ignited air also drives the entire fan blade system; both compressor blades and by-pass system. The end result is the by-pass air accounts for about 60% of total thrust, while the compressed and ignited air accounts for the remaining 40%. So the Stage 1 blades (front of the engine) act as a very fast propeller, forcing air through a straw, and ejecting it at a fast rate than the air entering the engine. The by-passed air also provides a sound dampening effect for the combustion nozzle. Think of the business-end of the engine as a donut. \n\nContaining the pressure change of the blades cutting the air vastly improves the efficiency and power output of a jet engine compared to a propeller. ",
"Prop airplanes are limited by the speed of the propellor. The Soviet Bear bomber used counter rotating propellers, and is considered one of the loudest airplanes in the world as the prop tips break the sound barrier.\n\nYou can make the propellers larger or have lots of blades (like the Bear) but I don't see any way that a prop plane could exceed Mach 1 in level flight.\n\nAny aviation engineers? I could be way off.",
"One big piece of it is how complex the piston engines are compared to jets.\n\nI'm going to go back to 1950s examples because that was the pinnacle of aircraft piston engines and beginning of good jet engines\n\nThe American B-36 bomber was originally designed in WW2, but on the back burner for a bit and flies in in August 1946, just a giant plane\n\nSix Pratt & Whitney R-4360-53 \"Wasp Major\" radial engines to power it originally, each engine required a dedicated 100 gal (380 l) oil tank\n\n28 cylinders, a super charger and a turbo charger, and 56 spark plugs - it weighed 3,870 pounds (1,760 kg)\n\nIn 1947 we have first flight of a US jet bomber, the B-47. Now it wasn't designed to fly as far as B-36, it was a medium range bomber for it's time. While the B-36 would fly from Texas to the Soviet Union, the B-47 would fly from Morocco, Alaska, Greenland or the UK to the Soviet Union.\n\nB-47 is powered by six General Electric J47-GE-25 turbojets\n\nIt weighed 2,554 pounds (1,158 kg) \n\nThe Wasp Major engines were known for their complexity and failure rates - \"Normal maintenance consisted of tedious measures, such as changing the 56 spark plugs on each of the six engines; the plugs were often fouled by the lead in the 145 octane anti-knock fuel required by the R-4360 engines. Thus, each service required changing 336 spark plugs.\" and the unofficial motto of the type was \"two turning, two burning, two smoking, two choking, and two more unaccounted for...\" because eventually the B-36 had four J47 jet engines added for extra power...10 total engines\n\nJets were much more reliable - the J47-GE-23 was rated to run 225 hours time between overhauls. As installed on the F-86F, it experienced one in-flight shutdown every 33,000 hours in 1955 and 1956"
]
}
|
[] |
[] |
[
[],
[],
[],
[
"https://www.grc.nasa.gov/www/k-12/UEET/StudentSite/engines.html"
],
[],
[],
[],
[],
[]
] |
||
2km778
|
how do laser rangefinders work?
|
explainlikeimfive
|
http://www.reddit.com/r/explainlikeimfive/comments/2km778/eli5_how_do_laser_rangefinders_work/
|
{
"a_id": [
"clmntnr",
"clmrsxs"
],
"score": [
2,
2
],
"text": [
"The rangefinder measures how long it takes for a laser beam to travel there and back, and then uses that data to calculate distance.\n\n",
"A LASER rangefinder consists of a LASER, and a receiver tuned to the LASER's frequency. The device shoots the LASER, and measures how long it takes for the reflection to arrive. \n\nIf the device and your target are a distance of D away, the light has to travel a distance of 2*D; D meters there, as well as D meters back. \n\nAs distance equals speed * time...\n2*D (the total distance travelled) = speed of light * Time \n\nIf the target is too close, the device might not be able to measure it.\nIf the target is too far away, the reflection might not return enough energy to the receiver in order to be measured. Or, if you shoot a specular reflector, like glass or water, energy won't likely reflect back to your device."
]
}
|
[] |
[] |
[
[],
[]
] |
||
1u9rdn
|
How did family members find out if a relative died during WWII?
|
This is question asking how people found out about a relative dying during WWII and from what I've seen in movies it shows a soldier turning up at the door to tell the mother or wife. How was this done in the UK? If a ship went down would this be broadcast in a paper or on a newsreel or would this be kept secret in case of spying? I don't think this has been asked before, if so I apologise. Thank you.
|
AskHistorians
|
http://www.reddit.com/r/AskHistorians/comments/1u9rdn/how_did_family_members_find_out_if_a_relative/
|
{
"a_id": [
"cegbdxp"
],
"score": [
3
],
"text": [
"As with most countries, by telegram. Typically they would inform the family that the relative was missing, e.g.: _URL_3_\n\nAs noted, a letter (usually from the CO) would follow.\n\nOf course, some of the missing turned up, I believe the Red Cross would get lists of POWs and inform the armed forces, who would then inform the families. This is a poor picture, but you can just make out the message: _URL_1_\nIf the person was found to have survived and not in enemy hands the good news would be shared: _URL_2_\n\nIn some cases the individual themselves would send a telegram basically saying \"I'm still alive!\".\n\nSadly, all too often a telegram was received, confirming the relative as dead. \n\nOf course for those confirmed dead the telegram was rather final : _URL_0_\n\nIf you search for \"ww2 telegram\" on google images you will find may scans/pictures of similar telegrams from all over the world."
]
}
|
[] |
[] |
[
[
"http://news.bbcimg.co.uk/media/images/66211000/jpg/_66211180_telegram.jpg",
"http://media.npr.org/programs/atc/features/2006/may/nagorski/telegram200-s6-c30.jpg",
"http://www.forcez-survivors.org.uk/biographies/biopicsprince/summersgill/TELEGRAM3.jpg",
"http://213squadronassociation.homestead.com/WidgeWight/Telegram.jpg"
]
] |
|
1s2716
|
why if i slowly submerge an oreo in milk will it completely sink in less than a minute but if i simply drop it in, it seems to float forever?
|
explainlikeimfive
|
http://www.reddit.com/r/explainlikeimfive/comments/1s2716/eli5_why_if_i_slowly_submerge_an_oreo_in_milk/
|
{
"a_id": [
"cdt6fas",
"cdt769f"
],
"score": [
3,
3
],
"text": [
"The surface tension of the milk holds it up. \n\nIf you look at water, you will see that the surface is like a thin rubber skin. This keeps the cookie afloat. Also, since most of it is above the liquid, it does not soak up as much. ",
"the slow submerging is letting milk seep into every air pocket.\nwhen you drop it, the oreo naturally rises, and since only one side is exposed to the milk, the air pockets hod it up"
]
}
|
[] |
[] |
[
[],
[]
] |
||
59a90j
|
Did the Soviet Union have competitive entrance examinations for Universities? If yes, how did they differ from the ones in Europe and US?
|
AskHistorians
|
https://www.reddit.com/r/AskHistorians/comments/59a90j/did_the_soviet_union_have_competitive_entrance/
|
{
"a_id": [
"d96yq3s",
"d975p3v",
"d97m2k7"
],
"score": [
124,
78,
2
],
"text": [
"As a follow up question to OP's question, how common was it for Soviet universities to increase the difficulty of the entrance exams for, so-called, \"undesirables\"?\n\n[This article](_URL_0_) highlights the unfairness of entrance exams given to prospective Jewish students at the mathematics department of Moscow State University. Was this the norm?",
"The answer is going to be extremely dependent on period. University entrance in the Soviet Union in the 1920s versus the 1980s is going to be considerably different. Far more different than if you made the same comparison in the West. Is there a particular time frame that interests you?",
"Follow up did soviet citizens choose their studies or was it chosen for them. "
]
}
|
[] |
[] |
[
[
"https://arxiv.org/pdf/1110.1556.pdf"
],
[],
[]
] |
||
7wwrph
|
How good were the Confederacy's other generals in regards to Robert E Lee? Or the Northern generals for that matter? Were they second-rate, or just as good as Lee himself?
|
The second part of my title is a bit misleading, my bad. I mean the other generals, such as Stonewall Jackson or Nathan Bedford Forrest, compared to Northern generals.
|
AskHistorians
|
https://www.reddit.com/r/AskHistorians/comments/7wwrph/how_good_were_the_confederacys_other_generals_in/
|
{
"a_id": [
"du53fh1"
],
"score": [
10
],
"text": [
"It might be best to start on a discussion of Lee just to clear up what we're looking at in terms of a measuring stick. OP's question presupposes that Robert E. Lee was one of, if not THE best general of the American Civil War. By \"best\" I assume this is a combination of factors including (1) scoreboard, or win/loss ratio, and (2) post-war tactical evaluation. For both categories, while we can get into a discussion about them, one has to understand that there are few contemporaries with whom we can compare Lee. From the Battle of the 7 Days onward, Lee wasn't commanding just a division or a corps, but an entire Army. In this way, on the southern side, we can really only compare him to Beauregard, Bragg, Albert Sydney Johnston, Joseph E. Johnston, and maybe Hood. No one else on that side commanded at the same level as Lee, really, so comparisons further down the line are somewhat moot. On the northern side, there are more comparisons, and we will get to those in a moment. \n\nBut for starters: was Lee a good general, nay, the best the Confederacy had? Most modern scholarship is still in agreement that Lee was indeed a very good general, and probably the very best the Confederacy had to offer, yes. While he wasn't perfect, and certainly made his fair share of mistakes, Lee did pretty well for himself through a combination of skill, intuition, attitude, and luck. When he had to run a defensive campaign (think Fredericksburg or the Wilderness Campaign), Lee was outstanding, and when we was on the offensive, he could also be superb (2nd Bull Run & Chancellorsville being wonderful examples). The man did have his faults, however, including a reluctance to commit his resources and energies to the western theater campaign, and his insistence on seeing a battle through despite evolving circumstances (Antietam and Gettysburg, though in the former instance, luck was on his side and it worked out for him). Lee also ran hot and cold when it came to communicating to his subordinates, and while some of them seemed to intuitively understand the vagueness of his orders and their intention (Jackson), others had difficulty (Ewell), and disastrous results followed. Except for Longstreet, though, Lee's win/loss record when comparing similar circumstances of battle is tops among the Confederate generals. \n\nAll that being said, it is hard for one to think of another General in the Confederacy except, perhaps, for Longstreet, who could have done a better job in the role. Lee knew how to get the most out of his army (both in terms of numbers and resources), and how to use them effectively regardless of the situation. He understood the political calculus of the conflict (hence his insistence on invading the north twice despite the tactical disadvantage), and managed his generals well on most occasions. When in battle, he knew how to place his men effectively, and was even better at making adjustments in the heat of battle to address breakthroughs and openings. Again, except for Longstreet, no other Confederate general demonstrated effectiveness on these levels with such consistency. What's more, Lee knew how to carry himself like a general, and understood the drama of leadership, and how one's bearing can move and influence an army. Like McClellan (whose battlefield acumen didn't come anywhere near Lee's), Lee's men truly loved him, and would do anything for him. This isn't something that can be discounted when discussing good generalship in the Civil War. \n\nSo, except perhaps for Longstreet, who seemed to be as good of a general on paper as Lee, and was just as sharp, pragmatic, and disciplined, I think it could be said that Lee was the best general the Confederacy had on their side. Joe Johnston was too timid and cautious, A.S. Johnston lost the one big battle he did fight (and died doing it), Beauregard was unrealistic, and Hood and Bragg were pretty much disasters from the word \"go\" in a commanding army role. As mentioned earlier, it is difficult to compare Lee with any other Confederate generals because the resumes just don't line up. \n\nAs for a comparison of Lee against northern generals, again, it is hard to compare. Lee was fighting a completely different campaign under circumstances lightyears removed from his Union counterparts (transportation and supply networks alone make this an apples v. oranges discussion). Tactically, one could make the argument that Grant, fighting a very cagey, experienced, motivated, and disciplined foe, displayed generalship on the same level as Lee during their head-to-heads of '64 and '65. Grant made several dynamic moves with his army that nearly flanked Lee on two occasions before successfully doing just that on route to Petersburg, where Grant bottled Lee up. Earlier, in 1863, Grant pulled off something just short of a miracle when he abandoned his supply lines, marched south of Vicksburg, crossed the Mississippi River, then fought to a siege that would eventually force the surrender of a massive Confederate garrison (and open the river back up to the Union). This was maybe the most impressive military feat of the entire war. Sherman's march to the sea and eventual dismantling of Hood's forces was nearly as impressive, as was the initiative showed by a young Major named Emory Upton who developed tactics during the Spotsylvania Courthouse campaign that leap-frogged military theory to where it would be in World War I. \n\nTD:LR - In the south, yes, we can reasonably argue that Robert E. Lee was one of, if not THE best general that the Confederacy had. When comparing Lee to generals in the north, it is more difficult, but an argument can be made that Union generals accomplished feats that were on the same level as Lee. \n\n[Sources: Bruce Catton: Army of the Potomac trilogy & 'Grant Moves South'; James McPherson, 'Battle Cry of Freedom'; Doris Kearns Goodwin, 'Team of Rivals'; Ronald C. White, 'American Ulysses']"
]
}
|
[] |
[] |
[
[]
] |
|
74q2kq
|
what led to the creation of the knights templar and what was their mo?
|
Why did they even exist after the church regained power?
|
explainlikeimfive
|
https://www.reddit.com/r/explainlikeimfive/comments/74q2kq/eli5what_led_to_the_creation_of_the_knights/
|
{
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"do0c8u8",
"do0hxv6"
],
"score": [
5,
2
],
"text": [
"During the Crusades, the Church controlled Jerusalem for a time, and this attracted pilgrimages to go see the holy land. The trip from Western Europe to the Levant was rough and dangerous. The Knights Templar were formed as a monastic order charged with securing the safety of pilgrims.\n\nBesides safety, they also served as a basic form of banking for pilgrims. Before you left, you'd deposit your valuables at a local Templar place, get a certificate of deposit, and afterwards you could either withdraw once you returned, or get an equivalent in treasure when you were in Jerusalem. This financial dealing made them relatively powerful.\n\nDespite the myths around them, their utility and purpose waned as the Muslims recaptured Jerusalem and the surroundings. Due to their power and ongoing feuds with the Knights Hospitaller, the French king eventually ordered them all arrested, and pressured the Pope to do the same. Some were killed, but most were given pensions and allowed to leave, or became absorbed into other monastic orders.",
"so I don't know much about their start.\n\nBut their MO was that you were already an extremely skilled knight before you joined. They didn't take green knights that hadn't fought a battle yet.\n\nSo you take the cream of the crop. Then they spend all day (when they aren't escorting pilgrims to holy sites) praying/other godly stuff, training, chores.\n\nSo the shear amount of time they spent training alongside other skilled knights made them even better. Couple this with the surplus funds that their banking system made (one of the reasons the french turned on them) giving them what for that time was a huge budget and they could afford to keep their men equipped with the best gear possible.\n\nOn the field they worked mainly as cavalry in chain mail (due to it being too hot for plate armor) and used a V formation in cavalry charges. They also trained closely with auxiliaries, non knights fighting on foot."
]
}
|
[] |
[] |
[
[],
[]
] |
|
1b3tco
|
why we flinch
|
For example:
If I look at the toaster when the bread pops up it makes me jump.
Why is this?
|
explainlikeimfive
|
http://www.reddit.com/r/explainlikeimfive/comments/1b3tco/eli5_why_we_flinch/
|
{
"a_id": [
"c93bhvo",
"c93ebxv"
],
"score": [
8,
2
],
"text": [
"Fight or flight instinct. When surprised, your body/brain makes itself ready to defend itself, or run for the hills...",
"Also, moving away from a collision when it happens dampens the overall effect or damage. Kind of like how you have to move your hands back to catch an egg. If you flinch back when someone punches you, it will hurt less. maybe?"
]
}
|
[] |
[] |
[
[],
[]
] |
|
523jlk
|
what will happen if we try to land on a gas gaint, like jupiter? will we come out from the other end, never being able to land?
|
explainlikeimfive
|
https://www.reddit.com/r/explainlikeimfive/comments/523jlk/eli5_what_will_happen_if_we_try_to_land_on_a_gas/
|
{
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"text": [
"No, as you enter the gas giant the pressure would increase and the interior gases would buoy your ship because their density would be increasingly higher as the molecules are squeezed closer together by gravity. You'd probably end up floating inside like being deep underwater rather than just passing straight through.",
"From my understanding, most gas giants have a solid core of (I think) rock/metals. But Jupiter's high Gravity, and high atmospheric winds/pressure would be make it too dangerous for us to \"land\" on the core. ",
"The Galileo probe entered Jupiter's atmosphere. Due to the immense gravity of the gas giants probes enter them at a really high speeds (tens of kilometers per second), so they need huge heat shields to survive. Afterwards you just have atmosphere without any surface below - but if you go too deep, pressure and temperature rise so much that no probe will survive it. The probe gets crushed, its pieces slowly descend further (because metals have a larger density than the hydrogen/helium atmosphere).",
"I see most people stuck in the real-world on this. Y'all need to borrow NdGT's Ship of the Imagination, allowing you to participate in the universe as an outside observer. \n\nMany scientists actually think there is a solid rocky core on most gas giants. Drop your ship low enough and you eventually reach some solid material, whether it's metallic hydrogen, silicates, a lump of uranium.",
"Think of it like a submarine going too deep into the ocean- you reach a point where the pressure is so immense you are crushed. The gas giants do not have \"air\" flowing over \"ground\" like a rocky planet, it's a dense atmosphere that gets so dense it's basically liquid, then so dense it's basically a gooey solid, much like the hot molten rock of the mantle layer on a rocky planet. While made of \"gas\" (Hydrogen) it's so hot, and so dense it's insane. \n\nThere may or may not be a solid core within but it's not going to be anything you can say you \"landed\" on considering the density on your way down. You would not say you \"landed\" on the core of Earth after drilling though super hot dense semi-liquid mantle.",
"The interior of a gas giant is actually quite dense...Jupiter's core is believed to be about twice as dense as the earth's.\n\nWhat makes a gas giant different is there is no sudden transition from atmosphere to surface...it just slowly gets denser and denser as you approach the center."
]
}
|
[] |
[] |
[
[],
[],
[],
[],
[],
[]
] |
||
60wd7u
|
How long did soldiers have to stand in the landing crafts during D-Day?
|
I was curious to try and find out how fatigued the soldiers involved in D-Day may have been before they landed. I've tried looking on the internet and cant seem to find a result for how long the soldiers had to stand in the Landing Crafts before and en-route to the landing zones.
|
AskHistorians
|
https://www.reddit.com/r/AskHistorians/comments/60wd7u/how_long_did_soldiers_have_to_stand_in_the/
|
{
"a_id": [
"df9wckd"
],
"score": [
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"text": [
"The convoys carrying troops departed from ports in southern England on the afternoon of June 5, 1944 and proceeded slowly across the channel with heavy air cover. They dropped anchor in their designated transport areas 23,000 yards offshore at roughly 0200 on June 6, at the same time that airborne forces were being landed. Boat teams were assembled, and loading and lowering of landing craft began at 0430, with H-Hour at 0630; so, roughly 2 hours. Elements of the 4th and 24th Cavalry Reconnaissance Squadrons proceeded in their landing craft two hours before H-Hour to clear out a small German observation post on the St. Marcouf Islands off Utah Beach.\n\n**Sources:**\n\n* [*Omaha Beachhead (6 June-13 June 1944)*](_URL_1_), by the Historical Division, War Department\n\n* [*U.S. Army in World War II, European Theater of Operations: Cross-Channel Attack*](_URL_0_), by Gordon A. Harrison"
]
}
|
[] |
[] |
[
[
"http://www.ibiblio.org/hyperwar/USA/USA-E-XChannel/index.html",
"http://www.ibiblio.org/hyperwar/USA/USA-A-Omaha/index.html"
]
] |
|
2bwp3h
|
What is the origin and historical context of so called, "honor killings?"
|
So, threads like [this one](_URL_0_) crop up from time to time, basically describing a victim (almost invariably female) being killed or injured for being sexually assaulted. These are described as honor killings, and appear to be occurring because of perceived shame brought upon the family of the victim as a result of the assault. So, when did this practice start? Where? Under what conditions? I know (or rather assume) that it's hard to look at the idea of crime, and perceptions thereof, throughout history (since something that's criminal today may have been acceptable in the past EDIT: and also clearly what's criminal in one place may not be in another, even within the same timeframe), but surely there's a context for what we see reported today.
|
AskHistorians
|
http://www.reddit.com/r/AskHistorians/comments/2bwp3h/what_is_the_origin_and_historical_context_of_so/
|
{
"a_id": [
"cj9so9s"
],
"score": [
2
],
"text": [
"hi! if you don't get responses here (or even if you do), it might be worth x-posting this question to /r/AskSocialScience and/or /r/AskAnthropology for their perspective"
]
}
|
[] |
[
"http://www.reddit.com/r/TrueReddit/comments/2bvp1r/struggling_to_keep_afghan_girl_safe_after_a/"
] |
[
[]
] |
|
4keecy
|
Would the night sky have appeared much brighter in the time of the dinosaurs?
|
Given that the universe is expanding, and that apparent brightness of celestial bodies is governed by the inverse square law, would there have been a noticeable difference in the brightness of the night sky during, say, the early Jurassic Period?
|
askscience
|
https://www.reddit.com/r/askscience/comments/4keecy/would_the_night_sky_have_appeared_much_brighter/
|
{
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"d3ehpyd",
"d3ekuy2",
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],
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56,
6,
5
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"text": [
"The universe is expanding, but gravity keeps small-scale (relatively speaking!) structures like galaxies - and even groups of galaxies - together. The volume of space containing all the stars we can see is a vanishingly small part of our galaxy! So the number of stars visible doesn't really change as the Universe expands. It might fluctuate a bit as the solar system makes its long orbit around the galactic center.",
"Getting some kind of handle on deep time is a real challenge. 65 million years ago, when the asteroid killed off the big dinosaurs, stars would still be pinpoints of light - 65 million years is less than half a percent of the 13.5 billion year accepted age of our visible Universe (so far). So I don't see a big change over that \"short\" geologic time as the Universe expands). (That's of course If I didn't screw up the math) The moon wouldn't have been much larger either - moving away from earth by 1.5 inches a year, it would only be about 1,500 miles closer than it is now (roughly 230k miles now). So all in all, I don't think things would have looked much different. Go back a couple billion years, when only bacteria were around, and you might have a different story.",
"As others pointed out, the expansion of the universe doesn't effect the distance between the solar system and the visible stars, since all those stars lie in our local region of the Milky Way. However, the number of stars visible in the sky would have fluctuated up and down in the past. The reason is that spiral arms of galaxies are dynamic waves of high density that sweep through the stars, much like a sound wave traveling through air compresses the molecules. The wikipedia page on [density wave theory](_URL_2_) has some good animations explaining how this works. \n\nAs the sun moves around the center of the Milky Way, it moves in and out of the spiral arms, as seen [here](_URL_1_). It takes the sun about 225 million years to complete its orbit within the galaxy, and the dinosaurs were around from 230 to 66 million years ago. Our current location in the Milky Way puts us in the [Orion spur](_URL_0_), a small arm of the Milky Way. There are larger arms that the sun passes through with a higher density of stars, as well as gaps with a lower density of stars. So at different points when the dinosaurs roamed the earth, the sky had both more and fewer stars in it."
]
}
|
[] |
[] |
[
[],
[],
[
"http://www.nasa.gov/mission_pages/sunearth/news/gallery/galaxy-location.html",
"https://commons.wikimedia.org/wiki/File:Galaxy_rotation_wave.ogv",
"https://en.wikipedia.org/wiki/Density_wave_theory"
]
] |
|
3ggsuw
|
why there are lions in india, but no tigers in africa?
|
explainlikeimfive
|
http://www.reddit.com/r/explainlikeimfive/comments/3ggsuw/eli5_why_there_are_lions_in_india_but_no_tigers/
|
{
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],
"text": [
" > Lions, leopards and tigers are all part of the Felidae family of cats, which originated in Africa and share a common ancestor. At some point, probably around 2 million years ago, one offshoot of Felidae migrated east toward Asia, and those cats evolved into the orange-, black-, and white-striped beasts we know today. Once established in Asia, however, tigers never returned to Africa.\n\nLike many species, their ancestors left Africa and evolved, and never returned."
]
}
|
[] |
[] |
[
[]
] |
||
20tvap
|
Why do larger land animals seemingly tend to have fewer legs (among those that have them)?
|
Mammals tend to have 4 legs max, birds have 2, lizards and dinosaurs have 4, and so on. On the other hand, insects, centipedes, and arachnids (which are mostly, but not always, quite small) have a bunch more legs.
Intuitively, it would seem as if having more to rest on would be helpful to counteract the square-cube law. Is there a fundamental reason larger animals don't have six legs to support them, or is it seemingly just by chance that it never evolved?
|
askscience
|
http://www.reddit.com/r/askscience/comments/20tvap/why_do_larger_land_animals_seemingly_tend_to_have/
|
{
"a_id": [
"cg6qvif",
"cg6rb8g",
"cg6vupg"
],
"score": [
2,
4,
6
],
"text": [
"Interesting question, I think the distinction might not be between small animals and large ones, but rather between invertebrates and vertebrates. \n\nMy speculation is that there is a tradeoff between the number of appendages an organisms has, and the range of motor control it can have with those appendages. This would produce two alternative evolutionary strategies, one using fewer appendages with greater motor control, and one using more appendages with less motor control. \n\nIt's possible we fell down an evolutionary path in one direction while invertebrates fell down the other by complete chance. Or, there is some reason for the split such as fundamental differences in our nervous systems. Sorry I can't say for sure, these are just my about thoughts about it! ",
"I've never heard a definitive answer to that, but I'll share my thoughts thanks to a side interest of mine (robotics) in which I've explored some of these issues.\n\nMore legs means more body to maintain. If there isn't an advantage to that \"more body\" natural selection works against it. In the case of primitive creatures the advantage is *stability* and *mobility*. It's much harder for a creature with six legs to fall over than one with four or two. In robotics, you'll see this in the huge number of [hexapod robots](_URL_0_) available to hobbyists.\n\nThe downside to hexapod robots is that they need a lot of power-hungry, relatively heavy, pricey motors -- generally three per leg for EIGHTEEN in total. Ugh. In that regard, a two-legged robot would be awesome -- but creating a two-legged robot that can walk reliably is very, very hard. Still-in-laboratory-research-phase kind of hard. What that tells me is that more likely than not, more primitive animals just don't have the brainpower to balance on fewer legs. As you go up the evolutionary ladder, sufficient processing power exists for locomotion on fewer legs, and the number of legs then goes down.\n\nSorry it's a cross-over answer, but it's the best I can do!",
"There is a huge difference in the way invertebrates and vertebrates develop, the initial stage a single fertilize egg is the same, but already after a few divisions you start noticing differences. What is important is that our legs are vastly different structures than the leg of a grashopper. \n\nVertebrates all share a common body plan with four limbs, in some linages they have been lost (e.g. snakes) in others they might have evolved to have a new function (e.g. wings in bats and birds, flippers in whales, ...). Also if you see how our own limbs develop and the bones fit together, it is difficult to see how an extra pair would be attached.\n\nInsects, centipedes and arachnids have a segmented body structure where limbs can form from the fold between parts of the exo-skeleton. Here evolution also seems to favor less, but highly functional limbs. The most recent common ancestor of all these species probably was something similar to a centipede. With lots of segments all with fairly similar legs, the developmental program involved is fairly simple and this is repeated for each segment. Over time a reduction of limbs has occurred and you see the limbs becoming highly specialized for a specific niche. But still here 6-8 seems to be the current optimum.\n\nSo this vast difference in development of vertebrates vs invertebrates is why invertebrates can have any number of legs, while vertebrates are limited to 4. \n\nNow vertebrates have evolved a host of features that allows them to grow larger then insects in most environments. There are some physical limitations to the size of insects due to their exoskeleton and circulatory system.\n\nedit: I hope this summery is clear, I could write volumes more about this. "
]
}
|
[] |
[] |
[
[],
[
"http://en.wikipedia.org/wiki/Hexapod_(robotics)"
],
[]
] |
|
apo0tx
|
From my understanding hundreds of years ago when a country would steal land to absorb into their empire, they’d invade and forcibly take the land they wanted. Now when countries want land they negotiate, buy and sell it, when did that change occur?
|
Basically to clarify when did countries stop invading each other to get land and start selling it to one another?
|
AskHistorians
|
https://www.reddit.com/r/AskHistorians/comments/apo0tx/from_my_understanding_hundreds_of_years_ago_when/
|
{
"a_id": [
"ega6pvr"
],
"score": [
12
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"text": [
"Your understanding is pretty much incorrect. \n\n\nFirst off, the entire idea of land being firmly and incontrovertibly owned by a particular sovereignty, with concrete territorial boundaries marked off, is roughly speaking a modern idea associated with what is commonly called \"Westphalian sovereignty\", after the Treaty of Westphalia of 1648. \"Westphalian sovereignty\" is when a ruler of a territory argues they have comprehensive, exclusive control over a specific, marked-off territory; many people cite Max Weber's later definition that a national sovereign in this mode of authority has to have a \"monopoly on violence\" within the territory. \n\n\nPrior to this point, most existing states, empires and polities in world history held territories in shifting and flexible ways. Often their claims to territory were informal and negotiable. They might claim some tax revenues, assert some rights of movement and power, but not insist that they had comprehensive authority over the inhabitants. So territories all across the world passed in and out of direct control by rulers. In a premodern context, rulers who identified land they wanted, invaded it, and most crucially kept it, are pretty rare, no matter where we're talking about. An invader might claim territory or rewards, but keeping that new conquest as part of a coherent new polity was a much less common event, and arguably a decent number of invading or conquering leaders didn't expect anything except tribute, etc. \n\n\nEven in a pre-Westphalian context, the mechanisms by which sovereigns (of a great many kinds) could expect to increase their territorial authority on a permanent basis were extremely diverse. Marriage or kinship alliances were a fairly common mechanism all around the world. Treaties or agreements were another (certainly in some cases coercive). Migration--or emigration--that changed the linguistic and cultural balance in a particular territory, and its loyalties to various sovereign powers, could sometimes (usually over centuries) change who was considered to be in possession of it. And there are premodern examples of money changing hands, more or less, and allowing a sovereign in one place to command authority of another. \n\n\nThe OP might also take note that it's not clear that relatively contemporary modes of territorial acquisition are effective or permanent. Only 150 years ago, \"countries stole land to absorb into their empire\" in Africa and Asia; several centuries before that in North and South America. But only a relatively short time ago (the 1940s-1960s) many postcolonial states were created that involved some degree of forcible recombination of territories that didn't necessarily identify with one another--processes that are still very costly for us today in many respects. It does not seem that the idea of \"stealing land\" through invasion is totally absent today. Moreover, I'm actually pretty hard pressed to think of an actual example in recent years of a current nation buying substantial territory from another territory and having the transfer of territory happen in an amicable and accepted way. So in that sense I'm not even sure what the OP is thinking of. "
]
}
|
[] |
[] |
[
[]
] |
|
5rttns
|
why do spinning objects seem to stay in the air longer?
|
explainlikeimfive
|
https://www.reddit.com/r/explainlikeimfive/comments/5rttns/eli5_why_do_spinning_objects_seem_to_stay_in_the/
|
{
"a_id": [
"dda2az5"
],
"score": [
2
],
"text": [
"Spinning stabilizes the object so that it doesn't wobble or flip over. This enables it to continue moving through the air smoothly. By itself this doesn't make it stay up any longer, just travel farther. \n\nHowever, if the object is also shaped like a wing (a Frisbee is), staying in the right orientation allows it to generate more lift for a longer time."
]
}
|
[] |
[] |
[
[]
] |
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