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1gz03u
what is a centromere?
explainlikeimfive
http://www.reddit.com/r/explainlikeimfive/comments/1gz03u/eli5_what_is_a_centromere/
{ "a_id": [ "cap7pan" ], "score": [ 2 ], "text": [ "During mitosis, a cell splits its genetic material in half, with each daughter cell getting an equal number of chromosomes. Before the chromosomes are split up, the DNA has to be copied so that way there are 2 copies of each chromosome to be spl...
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[ [ "http://www.macroevolution.net/images/centromere-274-362-10.jpg", "http://essayweb.net/biology/images/celldivision/anaphase.png" ] ]
5ny66i
why do powerful drag racing engines sound so terrible when they're in idle?
Maybe it just sounds terrible to me but it's really loud and sounds like it's going to cut off. As opposed to a regular car that runs fine.
explainlikeimfive
https://www.reddit.com/r/explainlikeimfive/comments/5ny66i/eli5_why_do_powerful_drag_racing_engines_sound_so/
{ "a_id": [ "dcf5wwd" ], "score": [ 6 ], "text": [ "When you have a fixed cam profile, as is the case for the majority of racing engines, you can either have a smooth idle or good power at the top RPMs. Race engines spend most of their time turning fast and don't need a smooth idle.\n\nLots of roa...
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[ [] ]
dawpij
why does light oscillate?
Maybe this is a stupid question, but I dont understand what force is driving photons in light beams to go up and down, making a sine wave. How often in which it oscillates determines the frequency yeah, but why does it do that in the first place? And why is it that when light is emitted, instead of scattering like indi...
explainlikeimfive
https://www.reddit.com/r/explainlikeimfive/comments/dawpij/eli5_why_does_light_oscillate/
{ "a_id": [ "f1vkhmk", "f1voh1q", "f1wvnv6" ], "score": [ 4, 4, 5 ], "text": [ "The oscillation of photons does not stem from a force. The oscillation is not movement as you would normally think of it. What happens is, an electric field collapses and forms a magnetic field next to ...
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[]
[ [], [ "https://www.physicsclassroom.com/class/light/Lesson-1/Wavelike-Behaviors-of-Light", "https://stargazerslounge.com/topic/168496-what-allows-an-electromegnetic-wave-to-oscillate/" ], [] ]
3klx1i
url shorteners and why can't webs just use it "natively"?
explainlikeimfive
https://www.reddit.com/r/explainlikeimfive/comments/3klx1i/eli5_url_shorteners_and_why_cant_webs_just_use_it/
{ "a_id": [ "cuyjjsd" ], "score": [ 2 ], "text": [ " This is a commonly posted topic here. Please see [these previous posts.](_URL_0_) If they don't entirely answer your question, you might create a new post with\na more specific question.\n\nTry our handy Search function sometime. :-)\nFor best r...
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[ [ "https://www.reddit.com/r/explainlikeimfive/search?restrict_sr=on&sort=relevance&t=all&q=url%20shortener" ] ]
bec4y8
Why is Israel hiding its nuclear project?
So, reading about the Cold War era I got to the point of nuclear powers, and was surprised to see that Israel never admitted up until today having nuclear weapons. It is stated in multiple books and online that Israel is 5/6th country to have nuclear weapons, between 1960s and 1970s (so either before or after China). F...
AskHistorians
https://www.reddit.com/r/AskHistorians/comments/bec4y8/why_is_israel_hiding_its_nuclear_project/
{ "a_id": [ "el4na5o", "el5k9ts" ], "score": [ 4, 13 ], "text": [ "Hi there -- u/restricteddata has written on this topic before. Not discouraging further answers, but [this post in particular](_URL_0_) may be of some interest to you.", "The US in the 1960s tried to strongly discourage...
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[ [ "https://www.reddit.com/r/AskHistorians/comments/5idd3e/when_and_how_did_israel_obtain_nuclear_weapons/" ], [] ]
4n1e3v
why do we put gnomes in our gardens?
explainlikeimfive
https://www.reddit.com/r/explainlikeimfive/comments/4n1e3v/eli5why_do_we_put_gnomes_in_our_gardens/
{ "a_id": [ "d400q0z" ], "score": [ 2 ], "text": [ "Because they look nice. Seriously, that's just about it. Putting statues in your garden started during the Renaissance and was dwarves and the like and has stuck around since. The standard lawn gnome comes from 1800s Germany.\n\nSource: _URL_0_" ...
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[ [ "https://en.wikipedia.org/wiki/Garden_gnome" ] ]
3krtcu
Why did the French wear blue uniforms during WW1? Did this not leave them poorly camouflaged?
AskHistorians
https://www.reddit.com/r/AskHistorians/comments/3krtcu/why_did_the_french_wear_blue_uniforms_during_ww1/
{ "a_id": [ "cv03vlk" ], "score": [ 17 ], "text": [ "It was a longstanding tradition. Other countries had recently adopted camouflage uniforms, and in 1912, French Minister of War Adolphe Messimy saw their advantages and tried to change the French uniform. However, there was mass protest. The c...
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1trfqn
why is there such a high education requirement for menial jobs?
Edit: [Example](_URL_0_)
explainlikeimfive
http://www.reddit.com/r/explainlikeimfive/comments/1trfqn/eli5why_is_there_such_a_high_education/
{ "a_id": [ "ceapijc", "ceapojb", "ceapt5x", "ceapx3e", "ceaq1sj" ], "score": [ 3, 2, 7, 2, 6 ], "text": [ "Define \"high education requirement\" and \"menial jobs\".", "Without an example given can't really accurately comment. I can say however that even on the...
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[ "http://www.careerbuilder.com/JobSeeker/Jobs/JobDetails.aspx?Job_DID=JHP7FV6VDFLHCYDX0Q6&siteid=cbindeed&ipath=EXINDsep_google_feed%2cEXGOO" ]
[ [], [], [], [], [] ]
3rs0ut
Did Hitler actually take away guns from the Jews?
Lately I have been seeing many posts on Facebook about Hitler taking away guns from the Jews before the holocaust. Is this true?
AskHistorians
https://www.reddit.com/r/AskHistorians/comments/3rs0ut/did_hitler_actually_take_away_guns_from_the_jews/
{ "a_id": [ "cwqsncl" ], "score": [ 48 ], "text": [ "From an [earlier answer on this topic](_URL_0_)\n\nit was actually Weimar Germany that instituted wide-scale legislation restricting firearms in 1922 with the *Republikschutzgesetz* (law for the protection of the Republic). Under the rubric of \...
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[ [ "https://www.reddit.com/r/AskHistorians/comments/3o4f89/what_was_the_state_of_gun_ownership_in_prefascist/", "http://www.ushmm.org/outreach/en/article.php?ModuleId=10007695", "https://shop.jpfo.org/images/products/57_large.jpg" ] ]
1hpon9
Who were the Denisova hominin?
Did these humans become part of the Homo sapiens line or a break off them or something different? Were Homo sapiens, Denisova hominin and Neanderthals the only humans around at the time?
AskHistorians
http://www.reddit.com/r/AskHistorians/comments/1hpon9/who_were_the_denisova_hominin/
{ "a_id": [ "cawn48b" ], "score": [ 2 ], "text": [ "History is only the story of humans that have left records; it isn't the study of things that have happened in the past unless they were recorded (hence this is PREhistory). You are thinking of anthropology. Try /r/anthropology for details.\n\nEd...
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[ [] ]
1jjllk
Did the Native Americans of the Great Plains and the West communicate with tribes farther east about the presence of white settlers before they actually met them?
AskHistorians
http://www.reddit.com/r/AskHistorians/comments/1jjllk/did_the_native_americans_of_the_great_plains_and/
{ "a_id": [ "cbfepde" ], "score": [ 4 ], "text": [ "There are a couple complications to this questions. First, for the southern Plains at least, contact with Europeans began in 1540s when de Soto's expedition into present day American Southeast attempted to retreat back to Mexico through Texas and...
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[ [] ]
2ksobn
My mom inherited a bunch of Roman Catholic artifacts. Here are a few of them. Anyone know more about them?
My mom inherited a bunch of Roman Catholic artifacts. Below are albums of a few of them. Let me know if you have any questions or need more images. 1. [Ancient chalice. Appears to be made of pewter or some kind of metal. No markings.](_URL_3_) 2. [Ancient hand painted pages. Possibly from Book of Hours from Tours, F...
AskHistorians
http://www.reddit.com/r/AskHistorians/comments/2ksobn/my_mom_inherited_a_bunch_of_roman_catholic/
{ "a_id": [ "clom757", "clorlij", "cloro6o" ], "score": [ 6, 12, 13 ], "text": [ "You may want to cross post this to /r/whatisthisthing in case you don't get the answers you're looking for over here.", "The book leaves look legit. The art gallery was a real place and their plat...
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[ "http://imgur.com/a/jxzVE", "http://imgur.com/a/JexDI", "http://imgur.com/a/4bP0y", "http://imgur.com/a/k85GE" ]
[ [], [], [] ]
6aif8t
what does it mean to testify before (us) congress?
[deleted]
explainlikeimfive
https://www.reddit.com/r/explainlikeimfive/comments/6aif8t/eli5_what_does_it_mean_to_testify_before_us/
{ "a_id": [ "dhesycl", "dhesz0o" ], "score": [ 3, 2 ], "text": [ "The House of Representatives and the Senate have, like the Parliament of the United Kingdom, a \"power of inquiry.\" To assist in their lawmaking power, they can call individuals to testify before the houses or their committ...
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[ [], [] ]
8pkl25
if tv remotes emit infra-red rays, then why does camera lens pick violet rays being emitted from the remote?
Normally I can't see any light being emitted from remotes, but when I use a mobile camera for viewing I see a bright violet-ish light coming from the remote
explainlikeimfive
https://www.reddit.com/r/explainlikeimfive/comments/8pkl25/eli5_if_tv_remotes_emit_infrared_rays_then_why/
{ "a_id": [ "e0bxvxm" ], "score": [ 9 ], "text": [ "First, a quick introduction to how camera sensors work:\n\nCamera sensors actually just see in \"black and white\". That is, they only measure light intensity, not frequency. The sensor itself doesn't know if a photon hitting it has the \"red\" w...
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[ [ "https://en.wikipedia.org/wiki/Bayer_filter" ] ]
7a3z49
Was there any existing plans on how the Axis countries would coexist in the event they won WW2?
Reposting this with help from u/jschooltiger so it does not fall into speculation. Basically I want to know if there are any existing plan on how the relations between Nazi Germany, Fascist Italy, and Imperial Japan would be with each other if they won the war. Hopefully someone can help me.
AskHistorians
https://www.reddit.com/r/AskHistorians/comments/7a3z49/was_there_any_existing_plans_on_how_the_axis/
{ "a_id": [ "dp7bx2s" ], "score": [ 10 ], "text": [ "Check this answer by /u/commiespaceinvader, it's quite in depth.\n\n_URL_0_" ] }
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[ [ "https://www.reddit.com/r/AskHistorians/comments/6i2qp1/what_was_germanys_plan_after_ww2/" ] ]
b4px7u
why is it necessary to shoe and maintain shoeing horses, but wild ones are fine?
explainlikeimfive
https://www.reddit.com/r/explainlikeimfive/comments/b4px7u/eli5_why_is_it_necessary_to_shoe_and_maintain/
{ "a_id": [ "ej8djaa", "ej8dlyn", "ej8e304", "ej8eoyc" ], "score": [ 9, 2, 2, 5 ], "text": [ "Wild ones don't walk of roads or pull vehicles on roads. This exposes them to a different sort of wear profile, which they have evolved to handle naturally. Working horses are do...
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[ [], [], [], [] ]
1mzyko
*Why* did the Luftwaffe fail to beat the RAF?
The RAF had Radar, superior fuel/petrol, slightly better planes but, they were outnumbered. Not to mention the Kriegsmarine was blockading the UK and limiting certain supplies; why did the Luftwaffe fail to beat the RAF in 1940? Was the RAF simply superior? Were British pilots merely better?
AskHistorians
http://www.reddit.com/r/AskHistorians/comments/1mzyko/why_did_the_luftwaffe_fail_to_beat_the_raf/
{ "a_id": [ "cce8uya" ], "score": [ 9 ], "text": [ "\n- RAF operated over it's own territory, it's fighters could stay in the air longer, it's pilots were not permanently lost after bailing-out, and aircraft forced to crash-land could be recovered. Also, bomber losses are much harder to replace in...
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1l9ng5
how can social security be in trouble when people pay through a social security tax to fund it.
I do not understand how SS could have funding issues if people get benefits that they have already paid into.
explainlikeimfive
http://www.reddit.com/r/explainlikeimfive/comments/1l9ng5/eli5how_can_social_security_be_in_trouble_when/
{ "a_id": [ "cbx22sq", "cbx23gg", "cbx2641", "cbx4r6c", "cbx6rxw" ], "score": [ 9, 4, 2, 2, 2 ], "text": [ "Well, its a little more weird and complex than that.\n\n\nFirst, you are paying in but the people who currently need it are drawing on your funding of it. As...
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[ [], [], [], [], [] ]
2dzl0v
The Battle of Britain has ended and I've just turned 18. I want to join the RAF as a fighter pilot. What is the recruitment process like? If I were successful, how long would I be training for before my first flight into battle?
I'm curious about what kind of people would be accepted into the RAF as a pilot during the second world war. Would they be from the very educated upper middle classes as films and stereotypes depict, or would they come from all kinds of backgrounds? Secondly, what was the training process like? I know that for mod...
AskHistorians
http://www.reddit.com/r/AskHistorians/comments/2dzl0v/the_battle_of_britain_has_ended_and_ive_just/
{ "a_id": [ "cjvdyss" ], "score": [ 2 ], "text": [ "I can partially answer your question, but I think other people with more knowledge would be able to give you a little more information.\n\nInitially, the RAF was very much an \"an old boys club\" and crew were expected to have attended public sch...
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[ [ "http://www.angusrobertson.com.au/books/lancaster-men-peter-rees/p/9781741752076?gclid=COy5jay1ocACFY98vQoduU4AXQ", "http://www.angusrobertson.com.au/books/battle-order-204-christobel-mattingley/p/9781741751611?gclid=CL2wgLu1ocACFYyXvQoduaYAvg" ] ]
4jsnte
why is a root canal preferable over say an extraction/implant?
[This video](_URL_0_) shows the root canal procedure and it seems like at most 50% of the actual tooth remains after drilling the internal tooth/roots and making room for the crown. Why is this preferable over just extracting the tooth and replacing it with an implant?
explainlikeimfive
https://www.reddit.com/r/explainlikeimfive/comments/4jsnte/eli5_why_is_a_root_canal_preferable_over_say_an/
{ "a_id": [ "d397qvk", "d39bbpo" ], "score": [ 2, 2 ], "text": [ "Root canal or implants are not the only options. There's also the \"old way\", extraction and a dental appliance (dentures). The emphasis on keeping all your teeth is relatively new - in past times, dentists had no compuncti...
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[ "https://www.youtube.com/watch?v=2SwgxFLuNQs" ]
[ [], [] ]
1mhuln
Has there ever been a time in history when white people have been persecuted because of their colour?
AskHistorians
http://www.reddit.com/r/AskHistorians/comments/1mhuln/has_there_ever_been_a_time_in_history_when_white/
{ "a_id": [ "cc9fzb9", "cc9hluh" ], "score": [ 8, 3 ], "text": [ "In Zimbabwe, after the end of apartheid, there have been a lot of incidents of white people being targeted because of their [race.](_URL_0_)\n\nWhile kind of understandable because of the earlier apartheid situation it is wh...
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[ [ "http://en.wikipedia.org/wiki/White_people_in_Zimbabwe#Violence_against_whites" ], [] ]
3z9659
Did the Roman navy use heavy armor and shields or were they lightly armored?
I'm debating with a friend who says the Romans used heavy armor just like their heavy infantry legions but I doubt it. The first thing is that I doubt there would be a need for such heavy armor on a ship and it would be hard to move around or function in such armor. Another thought is that all of the heavy equipment ...
AskHistorians
https://www.reddit.com/r/AskHistorians/comments/3z9659/did_the_roman_navy_use_heavy_armor_and_shields_or/
{ "a_id": [ "cykgaxg" ], "score": [ 3 ], "text": [ "Are you asking about marines or rowers? The vast majority of the people on any warship would be unarmed and unarmored rowers huddled below decks on their benches. Marines, however, were most certainly heavily armored and armed, that is well accep...
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eznb9x
how do insurance companies like geico, progressive, etc. have so much money to spend on ads?
explainlikeimfive
https://www.reddit.com/r/explainlikeimfive/comments/eznb9x/eli5_how_do_insurance_companies_like_geico/
{ "a_id": [ "fgodny6" ], "score": [ 5 ], "text": [ "There are roughly 265 million vehicles on the road in the US. Roughly 87% of those vehicles are insured. That leaves you with about 230 million vehicles insured in the US. \n\nThere are approximately 6 million car wrecks a year in the US. I'm ass...
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1cjc0l
Are there any theories on different ways to generate gravity besides having mass?
Is there any research let alone theories on different ways to generate gravity besides having a large mass? The question is mainly for its application for space and low gravity planets.
askscience
http://www.reddit.com/r/askscience/comments/1cjc0l/are_there_any_theories_on_different_ways_to/
{ "a_id": [ "c9h2l8r" ], "score": [ 4 ], "text": [ "It's not *real* gravity, but one idea for *simulating* gravity (which would be useful for space ships and stations in a microgravity orbit: spin a circular disc around at a constant velocity to generate a centrifugal force, making the outside of...
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[ [] ]
lob3k
Does dreaming have any effect on the qualify of sleep?
askscience
http://www.reddit.com/r/askscience/comments/lob3k/does_dreaming_have_any_effect_on_the_qualify_of/
{ "a_id": [ "c2uaknc", "c2uaknc" ], "score": [ 2, 2 ], "text": [ "Dreaming occurs during the R.E.M. cycle of sleep, the most important aspect of it. [This question](_URL_0_) also hinges around the same area that you are prodding at, as there is information there as well.\n\nAs far as dream...
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[ [ "http://www.reddit.com/r/askscience/comments/lmx6h/how_long_does_sleep_or_lack_thereof_affect_you/" ], [ "http://www.reddit.com/r/askscience/comments/lmx6h/how_long_does_sleep_or_lack_thereof_affect_you/" ] ]
axi301
why are sit-ups harder to do with your hands behind your head, rather then free?
[deleted]
explainlikeimfive
https://www.reddit.com/r/explainlikeimfive/comments/axi301/eli5_why_are_situps_harder_to_do_with_your_hands/
{ "a_id": [ "ehtqavd" ], "score": [ 7 ], "text": [ "Have you ever looked at a teeter-totter before? If one person on the teeter-totter is sitting at the very end and person on other side is sitting closer to the middle, then there's an imbalance and that imbalance spreads outward from the middle,...
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[ [] ]
fslx3t
why is quarantining for a few weeks so effective? wouldn't it just start spreading just as bad as soon as the quarantine ends?
explainlikeimfive
https://www.reddit.com/r/explainlikeimfive/comments/fslx3t/eli5_why_is_quarantining_for_a_few_weeks_so/
{ "a_id": [ "fm2523o", "fm25b0w", "fm25l3g", "fm284l0", "fm29dza" ], "score": [ 2, 4, 4, 3, 2 ], "text": [ "That's why quarantine may not only be a few weeks. It's hard for people to gage how long it will take for this to pass because what started as a few weeks cou...
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[ [], [], [], [], [] ]
650x5b
why does it feel like there's less viruses on the internet nowadays?
explainlikeimfive
https://www.reddit.com/r/explainlikeimfive/comments/650x5b/eli5_why_does_it_feel_like_theres_less_viruses_on/
{ "a_id": [ "dg6jk69", "dg6jo57" ], "score": [ 2, 5 ], "text": [ "Anti-malware is better than it's ever been, and malware is better at hiding than it's ever been.", "*Fewer\n\nAnd the purpose of viruses has shifted from being some piece of code that just fucks your system up, to being ...
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[ [], [] ]
22vqst
why do boxers get paid so much?
explainlikeimfive
http://www.reddit.com/r/explainlikeimfive/comments/22vqst/eli5_why_do_boxers_get_paid_so_much/
{ "a_id": [ "cgque09" ], "score": [ 2 ], "text": [ "If anything, why do athletes get paid so much? " ] }
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3hq3wo
What is the difference between amplitude (volume) and loudness?
I do not understand what the difference is between the amplitude and the loudness. In everyday life it is just synonymous, but I want to know what the difference is, scientifically. Thank you!
askscience
http://www.reddit.com/r/askscience/comments/3hq3wo/what_is_the_difference_between_amplitude_volume/
{ "a_id": [ "cua12i5" ], "score": [ 2 ], "text": [ "Amplitude is a feature of a signal, usually periodic signals like sine-waves. It is a measurement of the 'height' of the signal, the distance from the lowest point to the highest in whatever units the signal is in. If we were measuring the signal...
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2l6o1g
why do musicians (famous and average) choose to publish music through record label companies, as opposed to going to pandora/spotify/itunes radio/all the others directly?
Also, what do music record labels do that require so much of the profit? I understand why relatively un-famous musicians need help with marketing/distribution of their music, but for famous people, they already have a huge fan base to get the word out. It seems like streaming service companies are whining because it ...
explainlikeimfive
http://www.reddit.com/r/explainlikeimfive/comments/2l6o1g/eli5_why_do_musicians_famous_and_average_choose/
{ "a_id": [ "clrxz2s" ], "score": [ 4 ], "text": [ "For a lot of musicians, it's still easier to let someone else handle all of the details of dealing with distribution, marketing, and production. And since record labels have been doing this for a long time, they tend to have the resources to han...
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[ [] ]
cszfvk
During WWII, did German U-boats attack ships traveling from the UK to the US as well?
I hope this isn't a dumb question but I wasn't able to find anything about this. The goal of the Germans was to interrupt supplies for the UK. But did the Germans target ships traveling back as well? Did those have the same priority or were they slightly less important? Were they guarded just as well?
AskHistorians
https://www.reddit.com/r/AskHistorians/comments/cszfvk/during_wwii_did_german_uboats_attack_ships/
{ "a_id": [ "exhqyay", "exhr5ai" ], "score": [ 7, 5 ], "text": [ "Yes, westbound convoys were attacked, often just as heavily as ones heading eastwards. The goal of the German submarine offensive was to reduce the amount of merchant shipping available to the Allies. If it could be reduced ...
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[ [], [ "https://uboat.net/ops/convoys/routes.php?route=ON", "http://www.shipbuildinghistory.com/merchantships.htm#WORLD_WAR_I", "https://uboat.net/ops/convoys/routes.php", "https://uboat.net/ops/convoys/convoys.php", "uboat.net", "https://uboat.net/allies/merchants/" ] ]
teio3
What do emission spectra reveal about stars?
I've heard they can reveal composition, and velocity amongst other things, but what can we fully know just from the emission spectra of stars?
askscience
http://www.reddit.com/r/askscience/comments/teio3/what_do_emission_spectra_reveal_about_stars/
{ "a_id": [ "c4lxeuj" ], "score": [ 2 ], "text": [ "As you've already recognised, we can deduce the composition of a star from the spectra, assuming we know enough about the placement and surroundings to compensate for various shifts. From this we can classify the star, and with just a bit more in...
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[ [ "https://en.wikipedia.org/wiki/Hertzsprung-Russell_diagram" ] ]
10nghn
Obviously spices were central, but to what degree were drugs included in "the spice trade"?
What areas? Time periods? Specific plants and/or substances? Generic Ambrosia-like mixtures or recognizable specific drugs? Famous characters involved? Secret caravan cults? Feel free to include alcohol, tobacco, cocoa, medicines, etc. I'm collecting info for a drug cult historical sci fi novel that I'd like to wr...
AskHistorians
http://www.reddit.com/r/AskHistorians/comments/10nghn/obviously_spices_were_central_but_to_what_degree/
{ "a_id": [ "c6f0998", "c6f1n9g", "c6f2qu3" ], "score": [ 59, 17, 8 ], "text": [ "Opium is your answer. Go look into that.", "Read David Courtwright, [*Forces of Habit: Drugs and the Making of the Modern World* (2001).](_URL_0_) It's hilarious that someone put the main OCLC ent...
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[ [], [ "http://www.worldcat.org/oclc/44794855" ], [ "http://www.amazon.com/Spice-History-Temptation-Jack-Turner/dp/0375707050/ref=sr_1_1?ie=UTF8&qid=1348912731&sr=8-1&keywords=the+history+of+spice" ] ]
3ig8cs
is there a way commercial banks are creating their own money (digital or paper) without anyone knowing?
edit: what i mean is, with the advent of digital banking. can the bank create an account that belongs to no one, say some sum of money was deposited, lend that money that only exists digitally out and then collect it as money from a real person
explainlikeimfive
https://www.reddit.com/r/explainlikeimfive/comments/3ig8cs/eli5_is_there_a_way_commercial_banks_are_creating/
{ "a_id": [ "cug497p" ], "score": [ 2 ], "text": [ "Okay, this is going to be complicated, but bear with me. \n\nEconomists have names for different types of money. M0 is the sum of all the dollars bills and coins printed by the treasury. Banks do not increase the M0 supply. \n\nBut there are seve...
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[ [ "https://en.wikipedia.org/wiki/Fractional-reserve_banking#Example_of_deposit_multiplication", "https://en.wikipedia.org/wiki/Money_supply#Empirical_measures_in_the_United_States_Federal_Reserve_System", "http://www.federalreserve.gov/monetarypolicy/reservereq.htm" ] ]
f0xcdo
what causes eyes to get fatigued from reading for too long?
explainlikeimfive
https://www.reddit.com/r/explainlikeimfive/comments/f0xcdo/eli5_what_causes_eyes_to_get_fatigued_from/
{ "a_id": [ "fgzolv6" ], "score": [ 3 ], "text": [ "We actually have muscles in our eyes. These muscles constrict and relax to change the shape of the lens, which is how our eyes focus. Reading or looking at a screen for long periods of time requires these muscles to hold themselves in specific po...
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[ [] ]
55sqlg
How did the Romance language-speaking enclaves in former Dacia survive amongst Slavs, and how did they expand to the borders of modern-day Romania?
AskHistorians
https://www.reddit.com/r/AskHistorians/comments/55sqlg/how_did_the_romance_languagespeaking_enclaves_in/
{ "a_id": [ "d8dzvf6" ], "score": [ 6 ], "text": [ "The people speaking Proto-Romanian, the ancestor of Romanian language, are thought to have lived in a rather small area, hence the distinctive lack of dialects of Romanian (with the exception of Aromanian and other southern dialects which have sp...
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[ [] ]
7itd15
what does it mean to have something notarized?
explainlikeimfive
https://www.reddit.com/r/explainlikeimfive/comments/7itd15/eli5_what_does_it_mean_to_have_something_notarized/
{ "a_id": [ "dr19myq", "dr1gqj6", "dr1jnk9" ], "score": [ 7, 6, 2 ], "text": [ "A document that's been notarized has been approved by an a neutral and trusted public official called a notary public. Basically it means the notary witnesses and confirms the identity of the person or ...
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[]
[ [], [], [] ]
4s3an9
if we created a magnet that was say 1 inch in diameter and was a kilometer long, is it possible we can create monopoles on each end (north side doesnt connect to south side)
explainlikeimfive
https://www.reddit.com/r/explainlikeimfive/comments/4s3an9/eli5_if_we_created_a_magnet_that_was_say_1_inch/
{ "a_id": [ "d565m3b" ], "score": [ 2 ], "text": [ "by definition, no.\n\nevery north and south side of the magnet will connect. If the magnet is 1 long magnet of uniform orientation, than thats what it will be.\n\nIf you force opposite poles together, or separate magnets with a non magnet filler...
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[ [] ]
9xn98i
What did Augustus (Roman Emperor) read and study growing up that prepared him for office
Title says it all. I'm curios to learn what and how he learned.
AskHistorians
https://www.reddit.com/r/AskHistorians/comments/9xn98i/what_did_augustus_roman_emperor_read_and_study/
{ "a_id": [ "e9wlbqw" ], "score": [ 4 ], "text": [ "In terms of direct evidence for Augustus himself, we only have a very short description of his education in Suetonius (Life Of Augustus 84):\n\n\"From early youth he devoted himself eagerly and with utmost diligence to oratory and liberal studies...
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[ [] ]
aldo84
Great Grandpa was official photographer for WW2, recently found a torture picture and POW. Anyway to find out more info?
[deleted]
AskHistorians
https://www.reddit.com/r/AskHistorians/comments/aldo84/great_grandpa_was_official_photographer_for_ww2/
{ "a_id": [ "efd6ij8" ], "score": [ 4 ], "text": [ "Hello there! You're right, we don't have a lot of desire to host pictures of people being tortured. \n\nAs your question is related to looking for identification/information regarding military personnel, our [Guide on Military Identification](_UR...
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[ [ "https://www.reddit.com/r/AskHistorians/wiki/militaryrecords" ] ]
8bi2av
how can the bootes void, or the great void as it is sometimes called, be filled with stars and galaxies and still be called a void?
explainlikeimfive
https://www.reddit.com/r/explainlikeimfive/comments/8bi2av/eli5_how_can_the_bootes_void_or_the_great_void_as/
{ "a_id": [ "dx6u1y6" ], "score": [ 8 ], "text": [ "Because our definition of \"void\" (in regards to space) is not just _URL_0_ just means less than average density of matter compared to the rest of the observable universe." ] }
[]
[]
[ [ "empty.It" ] ]
3xarf8
why don't more companies collaborate on everything?
explainlikeimfive
https://www.reddit.com/r/explainlikeimfive/comments/3xarf8/eli5_why_dont_more_companies_collaborate_on/
{ "a_id": [ "cy309lp", "cy36hmx" ], "score": [ 2, 2 ], "text": [ "Because if there is no competition, your company doesn't have the chance to win more money than the rest. It's like the prisoner's dilemma:\n\n _URL_0_", "A company is a group of *people*, and each *person* is competing ...
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[ [ "https://youtu.be/t9Lo2fgxWHw" ], [] ]
bb5ftv
Will all stars in the universe die eventually?
I always tought that even if a star dies new ones will take its place and this process can go on forever. So will the stars cease to form and every other one will die?
askscience
https://www.reddit.com/r/askscience/comments/bb5ftv/will_all_stars_in_the_universe_die_eventually/
{ "a_id": [ "ekgp50b", "ekgqv0c" ], "score": [ 20, 9 ], "text": [ "Stars form from the free gas floating in the galaxy. This gas condenses and collapses into star clusters. Each star cluster has a mix of stars of different masses.\n\nThe most massive stars will explode as supernovae, throw...
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[ [], [] ]
s4glp
How does wasp and hornet killer work?
I recently got stung by a yellow jacket in my yard. I got my revenge like I was motherfucking Anakin Skywalker in Attack of the Clones when those god damn sand people killed his mom, but with wasp spray. How does that foaming wasp and hornet killer just zap those winged little fuckers dead almost instantly? Specifical...
askscience
http://www.reddit.com/r/askscience/comments/s4glp/how_does_wasp_and_hornet_killer_work/
{ "a_id": [ "c4b073n" ], "score": [ 11 ], "text": [ "I fucking hate bees, but at the same time I must acknowledge the vital role they play in pollinating things. So I guess it's a love-hate relationship we've got going.\n\nMany of the more popular wasp & hornet sprays use resmethrin (an insectic...
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[ [ "http://en.wikipedia.org/wiki/Pyrethroid" ] ]
l9hhd
- could someone explain to me the ethical theories of plato, aristotle, kant and mill by giving examples?
For example how would they respond to this moral dilemma: Should Batman kill the Joker?
explainlikeimfive
http://www.reddit.com/r/explainlikeimfive/comments/l9hhd/eli5_could_someone_explain_to_me_the_ethical/
{ "a_id": [ "c2qv4kq", "c2qw4ei", "c2qv4kq", "c2qw4ei" ], "score": [ 15, 9, 15, 9 ], "text": [ "Plato: The well-being of the soul *(\"eudaimon\")* is the highest goal of thought and action. This is achieved when each member of society commits to his *ergon*, his natural dut...
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[ [], [], [], [] ]
wtaex
Where does the heat from the Earth go?
If I heat something up, the heat eventually dissipates to the air... and then? Where does the heat from the air go? If it doesn't go anywhere and the amount of heat on Earth is constant, what about how Sun heats up the Earth, how come the Earth isn't unbearably hot already? It can't be just black body radiation, right?...
askscience
http://www.reddit.com/r/askscience/comments/wtaex/where_does_the_heat_from_the_earth_go/
{ "a_id": [ "c5g8q1q" ], "score": [ 4 ], "text": [ "Well, into space..." ] }
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[ [] ]
bcvnd2
how do rocks (track ballast) able to support a train?
Wouldn't these large size gravel shift when load is on top? How do, essentially, rocks support a train on its rails & sleepers?
explainlikeimfive
https://www.reddit.com/r/explainlikeimfive/comments/bcvnd2/eli5_how_do_rocks_track_ballast_able_to_support_a/
{ "a_id": [ "ektwhqd", "eku3bsw", "ekugzzd" ], "score": [ 10, 3, 2 ], "text": [ "1) I assume the gravel is compressed when it is installed, e.g. with a heavy roller and/or a vibrating plate, so that if it's going to move down and fill a hole then it does that while it's being insta...
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[ [], [], [] ]
fbwnf
How long can you survive drinking only water distilled from your own urine?
I read that recycling your urine isn't sustainable due to the buildup of toxins that would result, but if you remove the toxins by boiling and condensing it, how long could you do it?
askscience
http://www.reddit.com/r/askscience/comments/fbwnf/how_long_can_you_survive_drinking_only_water/
{ "a_id": [ "c1es4ee" ], "score": [ 6 ], "text": [ "Well, you also will have fluid losses other than urinary evacuation (sweating, water vapor in your breath), if the system is closed, ie no additional water is added, you will run out.\n\nOn a related note, I have read that drinking the water from...
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[ [] ]
ed1ymk
why are most houses that were made recently so ugly?
explainlikeimfive
https://www.reddit.com/r/explainlikeimfive/comments/ed1ymk/eli5_why_are_most_houses_that_were_made_recently/
{ "a_id": [ "fbf4zdz" ], "score": [ 2 ], "text": [ "The first reason is survivorship bias. There were tons of ugly buildings in the 50s. For example [Nissen huts](_URL_0_) were a cheep and fast way to build and ugly ass garage or barn and were very popular until the 60-70's. You don't see many to...
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[ [ "https://www.google.com/search?q=Nissen+hut&rlz=1CASHAN_enUS865&sxsrf=ACYBGNRMt6gzDLL8lyiue4UcRZYFyAoqFw:1576801291244&source=lnms&tbm=isch&sa=X&ved=2ahUKEwii8OHG-sLmAhVoh-AKHV7jB58Q_AUoAXoECBUQAw&biw=1366&bih=665" ] ]
18rbq6
Have there ever been proposed additions to the English alphabet?
Such as a 27th letter or removal of an existing one?
AskHistorians
http://www.reddit.com/r/AskHistorians/comments/18rbq6/have_there_ever_been_proposed_additions_to_the/
{ "a_id": [ "c8h9zqk", "c8hfjou", "c8hh1lo", "c8iea7l" ], "score": [ 13, 3, 5, 2 ], "text": [ "The two most notable ones off the top of my head were thorn (which got replaced by combining t and h) and ash (**EDIT:** which is apparently NOT related to the mushed together AE ...
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[]
[ [ "http://en.wikipedia.org/wiki/List_of_reforms_of_the_English_language", "http://en.wikipedia.org/wiki/English_alphabet" ], [], [ "http://hotword.dictionary.com/ampersand/" ], [] ]
4f1y8b
Is the sun soft or hard?
To give an example; if I was flying a spaceship (let's assume it can withstand the extreme conditions), and I wanted to enter the sun, would the ship just sail through or would it crash on the surface?
askscience
https://www.reddit.com/r/askscience/comments/4f1y8b/is_the_sun_soft_or_hard/
{ "a_id": [ "d259ezq", "d25mznr", "d264em5", "d267rpi", "d27vpw3" ], "score": [ 1906, 62, 6, 10, 2 ], "text": [ "To use your terminology, the edge of the Sun is rather soft. Take a look at [this graph of the matter density profile of the Sun](_URL_1_). Close to what...
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[]
[ [ "http://i.imgur.com/zBTlzq3.png", "http://i.imgur.com/X63zYEK.png", "http://i.imgur.com/Bltc00L.png", "https://en.wikipedia.org/wiki/Orders_of_magnitude_%28pressure%29", "http://th.physik.uni-frankfurt.de/~scherer/" ], [ "http://www.thesurfaceofthesun.com/index.html" ], [], [], ...
8bx6zu
What was the endgame for the Soviet Union in the Cold War?
Did the Soviet Union, Post-Stalin, ever have a real plan to 'win' the cold war? How did they plan to achieve this? Did they presume that the U.S. would be overthrown by some communist uprising or were they simply going to have perpetual standoff? What did the end-game look like? Did the Soviet plan involve an eventua...
AskHistorians
https://www.reddit.com/r/AskHistorians/comments/8bx6zu/what_was_the_endgame_for_the_soviet_union_in_the/
{ "a_id": [ "dxap3dm" ], "score": [ 14 ], "text": [ "I think that question is too far raging, and it'd be better served as something more focused, its a little bit like asking:\n\n\nWhat is the US endgame in the 21st century? Does it involve an eventual military conflict?\n\n\nIf you're interested...
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[]
[ [ "http://nationalinterest.org/feature/natos-master-plan-crush-the-soviet-union-battle-13420", "http://nationalinterest.org/blog/the-buzz/until-the-1970s-nato-thought-it-would-lose-conventional-war-21181", "https://www.reddit.com/r/AskHistorians/wiki/faq/wdst#wiki_...of_the_cold_war", "http://nation...
2ntw4c
what would happen if an illegal immigrant claimed that she had always lived in that country and had simply lost her id? even if they didn't believe her, what country would they deport her to if they didn't know? and if she had no money, would they just keep her locked up forever?
explainlikeimfive
http://www.reddit.com/r/explainlikeimfive/comments/2ntw4c/eli5_what_would_happen_if_an_illegal_immigrant/
{ "a_id": [ "cmgtwkn", "cmguu6o", "cmgvrcl" ], "score": [ 3, 4, 5 ], "text": [ "If she has an id she is in a computer somewhere. They would look it up ,then they would ask questions, then serve warrants.she'd spend time in jail or an immigration center till we decided what to do wi...
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[]
[ [], [ "http://en.wikipedia.org/wiki/Benjaman_Kyle" ], [] ]
bjt1jy
How fast does something have to travel in earths atmosphere before it begins to heat up?
When I hold my hand out of a car window it gets colder so I was wondering how much faster something would have to travel before it heats up like objects from space do when entering the atmosphere.
askscience
https://www.reddit.com/r/askscience/comments/bjt1jy/how_fast_does_something_have_to_travel_in_earths/
{ "a_id": [ "emb3xfk", "emd4vak" ], "score": [ 7, 6 ], "text": [ "When the air is hits an object going through it, it gets warmer, because kinetic energy energy gets converted to heat.\n\nThis also applies to your hand out of the car window scenario, however it is only about [0.4°C](_URL_1...
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[]
[ [ "https://en.wikipedia.org/wiki/Total_air_temperature", "https://www.wolframalpha.com/input/?i=20%C2%B0C%2B(100km%2Fh)%5E2%2F(2*1.005*kJ%2F(kg*K))" ], [ "https://www.youtube.com/watch?v=Jb4prVsXkZU", "https://www.grc.nasa.gov/WWW/BGH/stagtmp.html" ] ]
1158cu
If you took a breath of pure oxygen could you hold your breath longer than if you took a breath of normal air?
askscience
http://www.reddit.com/r/askscience/comments/1158cu/if_you_took_a_breath_of_pure_oxygen_could_you/
{ "a_id": [ "c6jfn4v", "c6jhgav", "c6jibez", "c6jitc8", "c6jj6zk", "c6jjdvx", "c6jkp11", "c6jlsze", "c6jlx3d", "c6jmpkr", "c6jn5hj", "c6jo3xd", "c6jtm2m", "c6jtzvc" ], "score": [ 399, 21, 70, 2, 1164, 3, 3, 5, 2, 5, ...
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[]
[ [ "http://news.discovery.com/human/breath-holding-human.html", "http://en.wikipedia.org/wiki/Static_Apnea" ], [], [ "http://www.ted.com/talks/david_blaine_how_i_held_my_breath_for_17_min.html" ], [ "http://en.wikipedia.org/wiki/Suicide_bag", "http://en.wikipedia.org/wiki/Hypercapnia" ...
d125bh
How do one way hashes work?
I understand encryption how that is many calculations, but how are hashes one way?
askscience
https://www.reddit.com/r/askscience/comments/d125bh/how_do_one_way_hashes_work/
{ "a_id": [ "ezhradt", "ezn9ymz", "ezubb2z" ], "score": [ 31, 4, 2 ], "text": [ "A one-way hash is a function which is easy to calculate forwards, but difficult to invert.\n\nFor example, SHA256 is conjectured to be a one-way hash function. An easy way to see the SHA256 hash of any...
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[ [ "https://en.wikipedia.org/wiki/One-way_function", "https://en.wikipedia.org/wiki/SHA-2", "https://en.wikipedia.org/wiki/Cryptographic_hash_function", "https://youtu.be/S9JGmA5_unY", "https://emn178.github.io/online-tools/sha256.html" ], [ "https://en.wikipedia.org/wiki/Confusion_and_di...
26pb51
How can we tell if a trait a characteristic about a person is genetic or environmental?
When I say environmental, I mean something that has been taught to us (either consciously or most likely more commonly unconsciously) because we either observed adults doing it as a child, or they. Can we be certain traits are entirely genetic or entirely environmental? Are we certain some traits are always a combi...
askscience
http://www.reddit.com/r/askscience/comments/26pb51/how_can_we_tell_if_a_trait_a_characteristic_about/
{ "a_id": [ "chte4w7", "chtexip", "chthma1" ], "score": [ 3, 2, 2 ], "text": [ "You might want to take a look at [epigenetics](_URL_0_), which is a study of where the rubber of genetics meets the road of environment.\n\nBasically *biological functions* are entirely due to protein a...
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[ [ "http://en.wikipedia.org/wiki/Epigenetics" ], [ "http://en.wikipedia.org/wiki/Francis_Galton#Correlation_and_regression", "http://www.scientificamerican.com/article/how-much-of-human-height/", "http://en.wikipedia.org/wiki/Heritability" ], [ "http://en.wikipedia.org/wiki/Twin_study", ...
8m4rsx
Did monotheism only develop in the ancient Near East (Akhenaten, Zoroaster, Judaism, etcetera), or have there been other instances of it in other parts of the world?
AskHistorians
https://www.reddit.com/r/AskHistorians/comments/8m4rsx/did_monotheism_only_develop_in_the_ancient_near/
{ "a_id": [ "dzl59f8" ], "score": [ 6 ], "text": [ "Your question almost answers itself, because a presumed historical Zoroaster (who we will for convenience define as the composer of the Gathas) would definitely not have lived in the Near East. Instead linguistic and textual evidence suggests he ...
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2107o5
why do i have an explosive bowel movement very shortly after eating indian food? it can't be getting through the gi tract that fast, right?
explainlikeimfive
http://www.reddit.com/r/explainlikeimfive/comments/2107o5/eli5_why_do_i_have_an_explosive_bowel_movement/
{ "a_id": [ "cg8cutw", "cg8kclb" ], "score": [ 4, 3 ], "text": [ "Many GI reactions are due to something simply being in the tract. When you eat some exotic food, your body may react to the unusual foods and spices regardless of where the food is in the digestive process.", "It is beca...
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[ [], [] ]
1ww28f
What forces /physical causes give a frisbee its lift, and why can't we manipulate them to create a flying saucer, similar to how we can utilize an airfoil to make a flying airplane?
askscience
http://www.reddit.com/r/askscience/comments/1ww28f/what_forces_physical_causes_give_a_frisbee_its/
{ "a_id": [ "cf681wf" ], "score": [ 5 ], "text": [ "The force that gives lift to a frisbee is the same aerodynamic lift utilized in a regular aerofoil ([Bernoulli's Principle](_URL_0_)). That lift force isn't balanced along the length of the disc and is generally larger at the front. Under normal...
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[ [ "http://en.wikipedia.org/wiki/Bernoulli's_principle" ] ]
21i1qi
motherboard types
What is the difference between the following motherboards? AMD AM3/AM3+ AMD FM2/FM2+ and the Intel series of Sockets? These are Socket 1150, 1155 and 2011 Why do brands like ASUS and Gigabyte sell Intel and AMD Motherboards? I don't understand this?
explainlikeimfive
http://www.reddit.com/r/explainlikeimfive/comments/21i1qi/eli5_motherboard_types/
{ "a_id": [ "cgd7abk", "cgd7ixz" ], "score": [ 3, 2 ], "text": [ "It's basically just that each type of CPU needs a different motherboard, hence all the different kinds. Some boards also have different features, such as integrated graphics.", "[Maybe this should help..](_URL_0_)" ] }
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[ [], [ "http://www.makeuseof.com/tag/cpu-socket-types-explained-from-socket-5-to-bga-makeuseof-explains/" ] ]
8azn1x
does epidural anaesthetic during childbirth inhibit uterine contractions
Epidural anaesthetic is just local anaesthetic in the epidural space right? But when the dentist gives you local you lose motor control of your lip as well? Does this happen with epidurals too? If so how do they stimulate contractions?
explainlikeimfive
https://www.reddit.com/r/explainlikeimfive/comments/8azn1x/eli5_does_epidural_anaesthetic_during_childbirth/
{ "a_id": [ "dx2smsu" ], "score": [ 4 ], "text": [ "Epidurals for child birth generally are analgesic, not anesthetic. \nAn analgesic is something that blocks pain (at the doses typically used for labor it isn't always 100% effective at that, but it definitely knocks it WAY down in terms of sever...
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[ [] ]
o2zho
How does an electric motor turn electrical current into physical force
I can imagine how electrical current could light up a light bulb. But to use an electric car as an example, I can't visualize electrical current causing the huge physical forces that these motors produce. How does this work?
askscience
http://www.reddit.com/r/askscience/comments/o2zho/how_does_an_electric_motor_turn_electrical/
{ "a_id": [ "c3e0lsx" ], "score": [ 3 ], "text": [ "Get a magnet, a battery, and some wire. Put the magnet near the wire, then connect both ends of the wire to the ends of the battery. The wire should jump or move. This is because a current generates a magnetic field. If you coil the wire up, ...
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[ [] ]
a017i3
why do shoes/tires have better grip with less surface area touching the ground?
explainlikeimfive
https://www.reddit.com/r/explainlikeimfive/comments/a017i3/eli5_why_do_shoestires_have_better_grip_with_less/
{ "a_id": [ "eadnuc0", "eadpvb8", "eadqegk" ], "score": [ 2, 8, 7 ], "text": [ "Since you (or your car) have a constant weight, smaller area means more force per unit area. Uniform large surfaces don't give water, snow, whatever, an easy path to escape from under you, which can al...
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[ [], [], [] ]
u78gt
Where would I find a cuneiform translation of a line from Gilgamesh?
I am looking to find what I believe is line 63 of the MB Ur tablet. Or line 166 of tablet VII in the Standard Babylonian version. It is in the passage where Enkidu tells Gilgamesh of his dream and says something along the lines of "The heavens thundered and the earth gave echo". Does anyone have any idea where I coul...
askscience
http://www.reddit.com/r/askscience/comments/u78gt/where_would_i_find_a_cuneiform_translation_of_a/
{ "a_id": [ "c4swqr9" ], "score": [ 5 ], "text": [ "_URL_0_\n\nClear sketches of the original tablets are way at the end" ] }
[]
[]
[ [ "http://www.gutenberg.org/files/11000/11000-h/11000-h.htm" ] ]
3rarra
Are there more even numbers or whole numbers?
Say that there are equal whole and even numbers because for every whole number, you can correspond it to an even number. For example, 1 corresponds to 2, 2 corresponds to 4 and so on. Each whole number has a corresponding even number, thus both sets are equal. But using this logic, why not take the more obvious appr...
askscience
https://www.reddit.com/r/askscience/comments/3rarra/are_there_more_even_numbers_or_whole_numbers/
{ "a_id": [ "cwn8m9n", "cwn9bbd" ], "score": [ 12, 3 ], "text": [ "You are asking about the [cardinality](_URL_1_) of a set and you have more or less stumbled upon how we define the size of sets. We say that the sets A and B have the same cardinality (written as |A| or |B|) if there is a b...
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[]
[ [ "https://en.wikipedia.org/wiki/Schr%C3%B6der%E2%80%93Bernstein_theorem", "https://en.wikipedia.org/wiki/Cardinality" ], [] ]
e2ml09
How did ancient engineers (Roman or otherwise) determine elevation in order to build water projects?
I was reading today about the stupendous achievement that is the [Pont du Garde at Nîmes](_URL_0_), which was so precisely engineered that it descends only 12.6 meters over its entire length, for an average gradient of 1 in 3000. I know there are [many](_URL_1_) [other](_URL_4_) [examples](_URL_3_) of such excellent ea...
AskHistorians
https://www.reddit.com/r/AskHistorians/comments/e2ml09/how_did_ancient_engineers_roman_or_otherwise/
{ "a_id": [ "f8wtz8z" ], "score": [ 51 ], "text": [ "The Romans had no good way to measure absolute elevation (i.e. height above sea level). They occasionally attempted to measure the height of mountains; but since they did not have barometers (or any concept of atmospheric pressure), they had to ...
[]
[ "https://en.wikipedia.org/wiki/Pont_du_Gard", "https://ancientwatertechnologies.com/2014/03/24/ancient-water-technologies-of-the-nabataeans/", "https://en.wikipedia.org/wiki/Evangelista_Torricelli", "https://en.wikipedia.org/wiki/History_of_water_supply_and_sanitation", "https://en.wikipedia.org/wiki/Marib_...
[ [ "http://www.romanaqueducts.info/aquasite/foto/lijntekdioptraheron.jpg", "http://www.romanaqueducts.info/aquasite/foto/lijntekchorobates.jpg", "http://penelope.uchicago.edu/Thayer/E/Journals/ISIS/12/3/Determinations_of_Heights_of_Mountains*.html" ] ]
8snvzp
At high altitudes how does unconsciousness due to hypoxia occur in 10-15 seconds if you can hold your breath for up to 3 minutes?
askscience
https://www.reddit.com/r/askscience/comments/8snvzp/at_high_altitudes_how_does_unconsciousness_due_to/
{ "a_id": [ "e135sx9" ], "score": [ 4 ], "text": [ "Short answer: You can't hold your breath for 3 minutes at high altitudes.\n\nAt high altitudes, there's a lot less air. Air exerts a lot of pressure, it's just normally balanced by having a similar pressure inside and outside of your lungs so yo...
[]
[]
[ [] ]
8pzvgm
why do wood pigeons hoot in the same melodic pattern?
explainlikeimfive
https://www.reddit.com/r/explainlikeimfive/comments/8pzvgm/eli5_why_do_wood_pigeons_hoot_in_the_same_melodic/
{ "a_id": [ "e0fqkn8" ], "score": [ 3 ], "text": [ "Many bird species have a very specific call that they all do. This is how they recognize fellow members of the same species at a distance" ] }
[]
[]
[ [] ]
dqxxd5
what is the process of a catholic confession, from walking through the church doors, to walking out afterwards?
explainlikeimfive
https://www.reddit.com/r/explainlikeimfive/comments/dqxxd5/eli5_what_is_the_process_of_a_catholic_confession/
{ "a_id": [ "f6bfmm9" ], "score": [ 7 ], "text": [ "when I was younger the confessionals were located in the back of my church. There was certain times that the priest held confession. The confessional was a booth separated by a screen you could do it anonymously or looking at the priest. I don...
[]
[]
[ [] ]
20ltvh
- how does someone get into whiskey/bourbons and able to pick up tastes?
Been a beer connoisseur for a while and have trained my palette to pick up many minute flavors. I really like anything aged in bourbon barrels but just can't get into picking up those flavors in the bourbon straight. All I get is heat when I sip. How can I get into bourbon and broaden my horizons. Thanks.
explainlikeimfive
http://www.reddit.com/r/explainlikeimfive/comments/20ltvh/eli5_how_does_someone_get_into_whiskeybourbons/
{ "a_id": [ "cg4icsm" ], "score": [ 2 ], "text": [ "Just like in beer, it takes training. You have to try a lot of different types and compare notes.\n\nIt helps to find one or two you really like, drink them a bit to become very familiar with them, then compare others to your \"base\"." ] }
[]
[]
[ [] ]
9gdjw2
why was half life 2 considered such a milestone in gaming?
explainlikeimfive
https://www.reddit.com/r/explainlikeimfive/comments/9gdjw2/eli5_why_was_half_life_2_considered_such_a/
{ "a_id": [ "e63bais", "e63cs1c", "e63dtbo", "e63eoc2", "e63er30", "e63esnw", "e63evz8", "e63fnsv", "e63fp8e", "e63g469", "e63g4dc", "e63g4dk", "e63gasx", "e63gf6i", "e63ghjs", "e63h76p" ], "score": [ 230, 281, 105, 6, 30, 17,...
[]
[]
[ [], [ "https://youtu.be/9j8jb21bo_k?list=PLpmG2JGHItwmcpN8nID6mtbCJGIac6lqt&t=379", "https://www.youtube.com/watch?v=6Kxy0Rd9EIA", "https://youtu.be/CMoB6Xg7XsE?t=11" ], [], [ "https://www.youtube.com/watch?v=GjDY3m1SMpw" ], [], [], [], [ "https://youtu.be/bp5vOgz8vyI?t=751...
4ks3fx
can hard liquors ever go bad?
explainlikeimfive
https://www.reddit.com/r/explainlikeimfive/comments/4ks3fx/eli5_can_hard_liquors_ever_go_bad/
{ "a_id": [ "d3hd4ou", "d3hi14u", "d3hm5d6" ], "score": [ 15, 14, 4 ], "text": [ "Hard liquor such as vodka have near limitless shelf lives when unopened, however, once the seal is broken and the liquor has been exposed to the air it will only last around 6-8 months", "Whisky i...
[]
[]
[ [], [], [] ]
wkpqu
How does Mithras fit into Zoroastrianism?
So, Mithras was a Persian deity that was popular in Rome. But, I was under the impression that Zoroastrianism was dualist with a good god/evil god. The Wikipedia page on Mithra calls him a [yazata](_URL_0_). But the article on yazatas isn't very good. So, how would your regular dude in ancient Persia have viewed Mi...
AskHistorians
http://www.reddit.com/r/AskHistorians/comments/wkpqu/how_does_mithras_fit_into_zoroastrianism/
{ "a_id": [ "c5e6nfm", "c5e8eiw", "c5efs4v" ], "score": [ 16, 7, 3 ], "text": [ "Sorry for the briefness and oversimplification...I browse this forum too late at night...but here goes:\n\nA yazata is anything to be worshiped in Zoroastrianism. Ahura Mazda is the highest yazata. The...
[]
[ "http://en.wikipedia.org/wiki/Yazata" ]
[ [], [], [] ]
2pb9ip
How was China able to stay so technologically advanced compared with the rest of the world throughout most of its history despite having little contact with other civilizations?
Other civilizations, both ancient and medieval, were more centrally located in Eurasia and had more contact with their neighbors. How was isolated China able to stay so far ahead of the other world civilizations despite trading with them little? If competition fueled advancement in post-industrial revolution Europe ...
AskHistorians
http://www.reddit.com/r/AskHistorians/comments/2pb9ip/how_was_china_able_to_stay_so_technologically/
{ "a_id": [ "cmvqp01" ], "score": [ 4 ], "text": [ "Firstly, China engaged in much more trade than you're suggesting. The silk road, running from central China through Central Asia and the Middle East to Europe was the longest trade route throughout much of human history - there was plenty of tech...
[]
[]
[ [] ]
cwyuam
what is piezo-electricity and what are its uses ??
explainlikeimfive
https://www.reddit.com/r/explainlikeimfive/comments/cwyuam/eli5_what_is_piezoelectricity_and_what_are_its/
{ "a_id": [ "eygpb6p", "eygr0x0", "eyj9j8e" ], "score": [ 7, 3, 2 ], "text": [ "Piezoelectricity is an effect found in some solid materials that causes a charge to build up when it's under stress (an applied force). This relationship makes possible to use electricity to cause defor...
[]
[]
[ [], [], [ "https://www.explainthatstuff.com/quartzclockwatch.html", "https://en.wikipedia.org/wiki/Crystal_oscillator", "https://gfycat.com/alienatedremarkablebluefintuna", "https://dosits.org/galleries/technology-gallery/basic-technology/hydrophonereceiver/" ] ]
umqq5
What is the physical volume of a visible rainbow?
It appears 2D whenever I see one. Is it like a tube or what? just curious.
askscience
http://www.reddit.com/r/askscience/comments/umqq5/what_is_the_physical_volume_of_a_visible_rainbow/
{ "a_id": [ "c4x06xl", "c4x2q3e" ], "score": [ 3, 2 ], "text": [ "_URL_0_\n\nA rainbow is a refractory effect. You're seeing light refracted from a collection of water droplets that happen to be in the correct position relative to you and the sun for you to see it. Someone standing in a ...
[]
[]
[ [ "http://en.wikipedia.org/wiki/File:Rainbow1.svg" ], [] ]
4h6e25
what is a css subreddit?
And what exactly is its purpose?
explainlikeimfive
https://www.reddit.com/r/explainlikeimfive/comments/4h6e25/eli5_what_is_a_css_subreddit/
{ "a_id": [ "d2ns334", "d2nwuvb" ], "score": [ 5, 3 ], "text": [ "CSS is cascading style sheets. Basically it enables admins of specific subreddits to create a look and potentially change some functionality (like removing downvote buttons) to help enforce the feel of the sub.", "\"CSS ...
[]
[]
[ [], [] ]
1ys64t
Can an α-particle ejected from a radioactive nucleus capture 2 of the nucleus's electrons and become a helium atom?
Or does, for example, Ra decay into Rn^2- and not Rn?
askscience
http://www.reddit.com/r/askscience/comments/1ys64t/can_an_αparticle_ejected_from_a_radioactive/
{ "a_id": [ "cfnanfs", "cfngi6t" ], "score": [ 6, 5 ], "text": [ "Captured from the atom that is undergoing the radioactive decay? I would say - impossible. \n\nImagine a marathon runner trying to get two drinks at the same time from a water station. Except that instead of running, he is d...
[]
[]
[ [], [ "http://journals.aps.org/pr/abstract/10.1103/PhysRev.35.217" ] ]
1xy5hf
in what way is the unionization of european states similar than or different from the unionization of early states and territories of the us?
explainlikeimfive
http://www.reddit.com/r/explainlikeimfive/comments/1xy5hf/eli5_in_what_way_is_the_unionization_of_european/
{ "a_id": [ "cffnqoi", "cffns74" ], "score": [ 3, 2 ], "text": [ "Different. They're not forming a federal government with explicit foreign affairs and military \"supremacy\" over the individual states. That is, local militaries are not being disbanded, and individual nations within the EU...
[]
[]
[ [], [] ]
uvlu0
Can someone explain the new prenatal DNA tests to me?
I've heard of current chorionic villus sampling and amniocentesis but don't know what they are. There was controversy over how the new test could cause more abortion, but after digging around, I don't really understand how the new test is different.
askscience
http://www.reddit.com/r/askscience/comments/uvlu0/can_someone_explain_the_new_prenatal_dna_tests_to/
{ "a_id": [ "c4yyf4m", "c4yyjg9" ], "score": [ 2, 2 ], "text": [ "you mean paternity tests? or chromosomal screening?\n\nThe [American Pregnancy Association](_URL_1_) can answer your questions, or the [Prenatal Genetics Center](_URL_0_)\n\nOr maybe you're referring to the new [non-invasiv...
[]
[]
[ [ "http://www.prenatalgeneticscenter.com/", "http://www.americanpregnancy.org/prenataltesting/paternitytesting.html", "http://blog.gosh.org/research/safer-new-prenatal-testing-could-avoid-the-risk-of-a-miscarriage/" ], [] ]
3ysrnf
How do you view old scholarly secondary sources? Should their conclusions be discounted because newer sources on the same issue exist?
For example, can a book about Salem witchcraft written in 1865 still be considered an acceptable source if it provides direction to its primary sources and generally meets the requirements of a scholarly publication? If a historian from Harvard in 1865 quotes Cotton Mather and offers a reasonable interpretation of the...
AskHistorians
https://www.reddit.com/r/AskHistorians/comments/3ysrnf/how_do_you_view_old_scholarly_secondary_sources/
{ "a_id": [ "cygbnye", "cygi8lz" ], "score": [ 2, 9 ], "text": [ "In general, the further a source is from contemporary historiography, the more skeptically I view it. Scholars of the past worked in different ways, with different biases, than we do today. In particular, approaches to race ...
[]
[]
[ [], [ "https://www.reddit.com/r/AskHistorians/comments/3xq447/monday_methodsfinding_and_understanding_sources/cy6rrc7", "http://digashkelon.com/current-projects/" ] ]
af7t5c
why are salty and fatty foods the tastiest things to eat when your drunk.
explainlikeimfive
https://www.reddit.com/r/explainlikeimfive/comments/af7t5c/eli5_why_are_salty_and_fatty_foods_the_tastiest/
{ "a_id": [ "edw7w1c", "edwko40" ], "score": [ 28, 3 ], "text": [ "They're always the tastiest, but when you're drunk the voice in your head that would usually say \"no that's bad for you\" just says HUNGRY", "You crave salty things because the alcohol is causing you to dehydrate. The ...
[]
[]
[ [], [] ]
ngyyn
How do forensics deal with identical twins?
Say an identical twin is charged with a crime. If there were no fingerprints left behind, is there any way to discern their dna from that of their brother or sister?
askscience
http://www.reddit.com/r/askscience/comments/ngyyn/how_do_forensics_deal_with_identical_twins/
{ "a_id": [ "c390afg", "c390c2h", "c390afg", "c390c2h" ], "score": [ 5, 2, 5, 2 ], "text": [ "Identical twins have identical DNA that cannot be distinguished from each other.\n\nThey do have different fingerprints, though.", "Starryrach is correct. Identical DNA, but th...
[]
[]
[ [], [], [], [] ]
un26v
When did the U.S. turn away from having a major religious presence in the government during the 20th century?
I have done some research on the Eisenhower Administration and their use of religion in government messages to contrast the atheistic communists, and I am curious when the government stopped using religion as a prominent message to common Americans.
AskHistorians
http://www.reddit.com/r/AskHistorians/comments/un26v/when_did_the_us_turn_away_from_having_a_major/
{ "a_id": [ "c4wuswz" ], "score": [ 6 ], "text": [ "I'm not certain on this answer at all, but I'm willing to bet it died, quickly, with Kennedy. His religion was a very touchy subject, so it would have been prudent of him and his administration to downplay religion.\n\nIt's also worth noting that...
[]
[]
[ [] ]
3h4kl7
why are some words considered more offensive/rude than others, despite meaning a very similar or even the exact same thing? i'm referring to swear words mainly.
explainlikeimfive
http://www.reddit.com/r/explainlikeimfive/comments/3h4kl7/eli5_why_are_some_words_considered_more/
{ "a_id": [ "cu45kwl" ], "score": [ 2 ], "text": [ "Similar question has been asked more than once today. It's weird.\n\nAll languages have curse or swear words; words used to describe acts, ideas, or concepts that are considered taboo by the culture that uses said language. These can vary widely ...
[]
[]
[ [] ]
16h1qt
When did the idea of secession from the United States become almost unthinkable? When did people start thinking of the US as an unbreakable collection of regions subject to a federal government?
Stated during the Civil War actually had the figurative balls to **secede** from what they called "the Union". As if a Union of states was so remarkable that they needed a capital U. These days it seems like common tradition that the 50 states of the USA are inseparable and united. No "Union" required, we're the USA. I...
AskHistorians
http://www.reddit.com/r/AskHistorians/comments/16h1qt/when_did_the_idea_of_secession_from_the_united/
{ "a_id": [ "c7vyetd", "c7vyww3" ], "score": [ 3, 2 ], "text": [ "As a practical matter, the Civil War decided the issue, however, the Supreme Court officially ruled on the issue in Texas v. White in 1868.", "The idea of succession up until the Civil War fluctuated based on the politic...
[]
[]
[ [], [] ]
28zou3
why is it that i wake up right before the good parts
When ever I have an amazing dream, and I am either about to have sex, or jump off a plane, I always wake up right as I am about to do it. I don't just wake up normal and tired, I wake up just as if I'm a actually going to do that action, whether it with a boner or with my heart pumping as i get ready to skydive. What c...
explainlikeimfive
http://www.reddit.com/r/explainlikeimfive/comments/28zou3/eli5_why_is_it_that_i_wake_up_right_before_the/
{ "a_id": [ "cig2x11", "cig7i9d" ], "score": [ 2, 2 ], "text": [ "I remember reading that the \"good\" part gets you excited and that excitement is what may contribute to you waking up.", "I believe it has something to do with your brain not being able to create something it has never ...
[]
[]
[ [], [] ]
68bdct
If time is dependent on speed, what is the reference point?
If you move faster it is shown that time is passing slower. But since our earth is already moving around the sun and the solar system is moving to (...), what is the reference point that matters for the velocity?
askscience
https://www.reddit.com/r/askscience/comments/68bdct/if_time_is_dependent_on_speed_what_is_the/
{ "a_id": [ "dgx4yz9" ], "score": [ 3 ], "text": [ "There isn't any special reference point that matters. Your results simply depend on whichever reference frame you happen to find most convenient." ] }
[]
[]
[ [] ]
2sinku
why do patents expire?
I know it's probably a stupid question, but I'm wondering.
explainlikeimfive
http://www.reddit.com/r/explainlikeimfive/comments/2sinku/eli5_why_do_patents_expire/
{ "a_id": [ "cnpsba5", "cnpsnp5", "cnpsxav", "cnpumra" ], "score": [ 3, 2, 2, 2 ], "text": [ "So that a patented device or technique or medicine cannot remain proprietary forever. This is important because it would then allow for people to later build upon whatever was prev...
[]
[]
[ [], [], [], [] ]
3d3wjf
how did internet explorer and chrome end up so different?
I'm not an IT person, but I find IE awkward, while Chrome is smooth and more user-friendly. And there is a general loathing towards IE, from what I've seen. Presumably though, both groups tried to make them the best offering possible. How did they end up being so different?
explainlikeimfive
http://www.reddit.com/r/explainlikeimfive/comments/3d3wjf/eli5_how_did_internet_explorer_and_chrome_end_up/
{ "a_id": [ "ct1jtm5" ], "score": [ 4 ], "text": [ "Internet Explorer has a lot more history than Chrome has.\n\nIn the mid-late 90's, Microsoft had managed to tie in business deals with a lot of PC manufacturers, governments, schools, and so on to make Windows the default operating system on some...
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[]
[ [] ]
h0tnt
What if Venus turned out to be more like Earth?
Also, consider that intelligent life arose on Venus around the same time as humans on Earth, at what point would we both be detectable to each other? How would his affected the scientific and technological development timelines? Would there be an explosion in science in the discovery of such a near by intelligent neigh...
askscience
http://www.reddit.com/r/askscience/comments/h0tnt/what_if_venus_turned_out_to_be_more_like_earth/
{ "a_id": [ "c1rqdyz", "c1rqhwt" ], "score": [ 3, 2 ], "text": [ " > Also, consider that intelligent life arose on Venus around the same time as humans on Earth, at what point would we both be detectable to each other?\n\nProbably a little after we both developed radio. If not the first p...
[]
[]
[ [], [ "http://scienceblogs.com/laelaps/2007/10/troodon_sapiens_thoughts_on_th.php", "http://dinosaurs.about.com/od/carnivorousdinosaurs/p/troodon.htm", "https://secure.wikimedia.org/wikipedia/en/wiki/Cambrian_explosion" ] ]
mzhdg
why do you need to apply pressure to bullet wounds?
Doctors say it. People in movies say it. Why is it?
explainlikeimfive
http://www.reddit.com/r/explainlikeimfive/comments/mzhdg/eli5_why_do_you_need_to_apply_pressure_to_bullet/
{ "a_id": [ "c3534mp", "c3534mp" ], "score": [ 10, 10 ], "text": [ "pressure slows the bleeding and helps promote clotting. \n\nEither that or they are afraid the bullet will shoot back out of the wound and kill someone else.", "pressure slows the bleeding and helps promote clotting. ...
[]
[]
[ [], [] ]
2hxmcd
how were large purchases made in gold coins during the middle ages? i.e. 2 million gold pieces?
Seems like a lot of weight in metal to be hauling around.
explainlikeimfive
http://www.reddit.com/r/explainlikeimfive/comments/2hxmcd/eli5_how_were_large_purchases_made_in_gold_coins/
{ "a_id": [ "ckwxuk1", "ckwxvyv", "ckwxx79" ], "score": [ 2, 2, 4 ], "text": [ "It wasn't. A couple chest of gold could buy whole states", "For large purchases you'd have gold in a bank, you'd then get a bank note (precursor to modern money) for the amount in question, you'd gi...
[]
[]
[ [], [], [] ]
11w8h4
what exactly happens when you see a beam of light?
Sorry if you guys think this is a dumb question, but I'm really curious. Isn't light supposed to travel straight? Isn't light supposed to reach your eyes for you to see something? How is light supposed to reach your eyes if it travels straight in a direction away from you?
explainlikeimfive
http://www.reddit.com/r/explainlikeimfive/comments/11w8h4/what_exactly_happens_when_you_see_a_beam_of_light/
{ "a_id": [ "c6q4h99" ], "score": [ 7 ], "text": [ "The space between the light source, and whatever it is being shone upon is not empty. In fact, it's got lots and lots of stuff bouncing around in it. Light is hitting those things and bouncing off them in not-quite-random directions. Dust mote...
[]
[]
[ [] ]
4a9nzr
why isn't the board game go as popular or mainstream around the world as.chess?
explainlikeimfive
https://www.reddit.com/r/explainlikeimfive/comments/4a9nzr/eli5_why_isnt_the_board_game_go_as_popular_or/
{ "a_id": [ "d0yihxz", "d0ykfqm" ], "score": [ 6, 8 ], "text": [ "Partly the game isn't popular because not enough people play it. Without opponents, you don't practice. Without practice, you don't get better. And if you suck, the game is no fun. \n\nI own a board, and have taught a few fr...
[]
[]
[ [], [] ]
2zyp6i
when muslims want sharia, what does that mean? does it mean that everyone, even non muslims should abide by those rules as well?
explainlikeimfive
http://www.reddit.com/r/explainlikeimfive/comments/2zyp6i/eli5_when_muslims_want_sharia_what_does_that_mean/
{ "a_id": [ "cpnhx1t", "cpnibkk" ], "score": [ 6, 3 ], "text": [ "Yes, that's what it means.\n\nChristians and Jews are specifically given the right to pay a tax, so long as they demonstrate that they are subservient to Islamic authorities, and are exempt from some of the prohibitions impo...
[]
[]
[ [], [] ]
18s9ft
why doesn't earth spiral closer and closer to the sun due to the sun's gravity?
explainlikeimfive
http://www.reddit.com/r/explainlikeimfive/comments/18s9ft/why_doesnt_earth_spiral_closer_and_closer_to_the/
{ "a_id": [ "c8hif1x", "c8hllo5", "c8hnnnu" ], "score": [ 10, 3, 2 ], "text": [ "Because the Earth has enough velocity (that is, kinetic energy) to keep from falling into the sun. \n\n**WARNING: BUCKET ON A STRING ANALOGY APPROACHETH**\n\nSo you've got your bucket on a string, sw...
[]
[]
[ [], [ "http://en.wikipedia.org/wiki/Gravitational_wave#Orbital_decay_from_gravitational_radiation" ], [ "http://en.wikipedia.org/wiki/Space_elevator", "http://i.imgur.com/PoIFZrc.gif" ] ]
6r5m3g
why are humans not tired anymore shortly after contact with water on their bodies, for example in the shower after waking up in the morning or splashing water in their faces?
explainlikeimfive
https://www.reddit.com/r/explainlikeimfive/comments/6r5m3g/eli5_why_are_humans_not_tired_anymore_shortly/
{ "a_id": [ "dl2hb21" ], "score": [ 3 ], "text": [ "It's an instinct thing. Our body's associate water on our face with one of two immediate hazards. One rain and foul weather. And two being in a large body of water and being at risk of drowning. Our body places priority on not dying and thus we a...
[]
[]
[ [] ]