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15yubz
how companies electronically surveil their employees
A few things I'm curious about, as I am not in this line of work at all. I have always wanted to know how it's done. Some of the main items I'm wondering about (Warning - severely amateur questions incoming): 1) Internet browsing. Can network administrators see every page that I go to? I assume so, but I doubt they ar...
explainlikeimfive
http://www.reddit.com/r/explainlikeimfive/comments/15yubz/eli5_how_companies_electronically_surveil_their/
{ "a_id": [ "c7r2nww", "c7r2sux" ], "score": [ 5, 2 ], "text": [ "1) Yes, some firewalls will show it in real time. Some will show logs. Whether or not they go through logs depends on how big of a company, and how much they suspect you of being naughty. Sometimes they just have alerts on s...
[]
[]
[ [], [] ]
6qxq61
What was the air combat effectiveness of the Me-262? Did the Luftwaffe ever develop strategies and tactics that made it an effective fighter?
I am aware of the technical achievements of the design, but I am wondering about the application.
AskHistorians
https://www.reddit.com/r/AskHistorians/comments/6qxq61/what_was_the_air_combat_effectiveness_of_the/
{ "a_id": [ "dl1ehzk" ], "score": [ 6 ], "text": [ "There was a real discrepancy between the Me-262's reputation and the actual results it achieved in German service. The sorties of 262 units often showed that it could not translate the technical advantages of the turbojet into masses of Allied ai...
[]
[]
[ [ "https://www.youtube.com/watch?v=ZoLLDi-M3fk" ] ]
77i9hl
security certificates (root, wildcard, etc)
explainlikeimfive
https://www.reddit.com/r/explainlikeimfive/comments/77i9hl/eli5_security_certificates_root_wildcard_etc/
{ "a_id": [ "dom2hvg" ], "score": [ 2 ], "text": [ "Certificates are cryptographically signed electronic documents that are generated and released by \"certificate authorities\". The certificate authority is an organization that says \"Okay, we're going to issue all of these certificates. We tru...
[]
[]
[ [ "foo.com", "www.foo.com" ] ]
6466ep
Did America finally enter WWII to stop the Holocaust or because Germany was trying to take over Europe (and eventually the world)?
AskHistorians
https://www.reddit.com/r/AskHistorians/comments/6466ep/did_america_finally_enter_wwii_to_stop_the/
{ "a_id": [ "dfzq28z" ], "score": [ 4 ], "text": [ "America officially entered WWII because it was attacked by Japan. The United States declared war on Germany on December 11 because Germany had declared war on the United States that same day. The declaration passed unanimously in both the Senate ...
[]
[]
[ [] ]
6pl072
on a subatomic level, what stops two objects made of the same exact material from joining and forming a bigger object? what force is there that repels the two objects?
explainlikeimfive
https://www.reddit.com/r/explainlikeimfive/comments/6pl072/eli5on_a_subatomic_level_what_stops_two_objects/
{ "a_id": [ "dkq5lz6", "dkq5nwd", "dkq68sv" ], "score": [ 5, 2, 23 ], "text": [ "Metals, that do not have an oxide layer on them (usually cut or made in a vacuum) *will* actually stick together and \"form a bigger object\". It's called cold welding.\n\nSome materials lend themselve...
[]
[]
[ [], [], [ "http://img09.deviantart.net/b1a1/i/2009/075/0/7/cut_wood___texture_by_steppelandstock.jpg" ] ]
4sevnr
Would a blind synesthetic person be able to see sounds?
askscience
https://www.reddit.com/r/askscience/comments/4sevnr/would_a_blind_synesthetic_person_be_able_to_see/
{ "a_id": [ "d58t2we", "d59206s" ], "score": [ 2, 6 ], "text": [ "Yes In theory; IF the right nerves connected. AND Depends on how said person is blind. If they are blind because of their eyes it would work. But if they are blind because of occipital lobe damage then no they wouldn't be ab...
[]
[]
[ [], [ "http://www.sciencedirect.com/science/article/pii/S0010945208703563", "http://www.ncbi.nlm.nih.gov/m/pubmed/15460512/" ] ]
1ieuir
What did a serf have that a slave didn't?
I know there were lots of slaves and lots of serfs, but just looking at perhaps agricultural slaves in America vs Russian serfs (who, I am given to understand, had some of the worst conditions of all European serfs) in the 1700s. From some of the popular media portrayals, it seems like a serf was pretty much a slave wi...
AskHistorians
http://www.reddit.com/r/AskHistorians/comments/1ieuir/what_did_a_serf_have_that_a_slave_didnt/
{ "a_id": [ "cb3u3mt", "cb43pit" ], "score": [ 250, 37 ], "text": [ "Firstly, in the early 18th century there were not just serfs in Russia, but also slaves. In Russia, slavery was abolished by Peter the Great in 1723.\n\nThe difference in position was not about having better opportunities...
[]
[]
[ [], [] ]
20j7ak
why are cpu's so expensive?
explainlikeimfive
http://www.reddit.com/r/explainlikeimfive/comments/20j7ak/eli5_why_are_cpus_so_expensive/
{ "a_id": [ "cg3rcya", "cg3rebt", "cg3rkl4", "cg3rlwk", "cg3v424" ], "score": [ 14, 8, 2, 3, 2 ], "text": [ "They are very hard to make. They are sandwiches of various metals and semiconductors formed into billions of microscopic structures which are sensitive to th...
[]
[]
[ [], [], [], [], [] ]
5rsuz4
are movie theaters dying due to changing culture or economic reasons?
I guess my last topic was too narrow, so I made it less narrow. _URL_0_
explainlikeimfive
https://www.reddit.com/r/explainlikeimfive/comments/5rsuz4/eli5are_movie_theaters_dying_due_to_changing/
{ "a_id": [ "dd9va9t", "dd9vbyf", "dd9vdsp", "dd9vscj", "dd9xdfe", "dd9xpav", "dd9xr40", "dda35df", "dda3e32", "dda7bwo", "ddapvn0" ], "score": [ 29, 16, 7, 45, 3, 26, 21, 7, 2, 9, 2 ], "text": [ "I think they are dyin...
[]
[ "https://www.reddit.com/r/explainlikeimfive/comments/5rrr2e/eli5_why_are_movie_theaters_dying/" ]
[ [], [], [], [], [ "https://www.cinemec.nl" ], [], [], [], [], [], [] ]
5vii3p
why countries with deficitary balance of payments try to devalue its currency to export more goods instead trying to strengthen the same currency to make imports cheaper?
explainlikeimfive
https://www.reddit.com/r/explainlikeimfive/comments/5vii3p/eli5_why_countries_with_deficitary_balance_of/
{ "a_id": [ "de2aw79", "de2bpiz" ], "score": [ 3, 4 ], "text": [ "Because strengthening a currency isn't an option. It's super easy to weaken it though. Strenghtening on the other hand would require a country to improve their perceived image. Like, ... requiring some actual good work. Unli...
[]
[]
[ [], [] ]
2y2npp
With the amount of planes that were shot down during WW2, what happened to the debris?
I'm curious if the planes caused any significant damage to unsuspecting cites or towns.
AskHistorians
http://www.reddit.com/r/AskHistorians/comments/2y2npp/with_the_amount_of_planes_that_were_shot_down/
{ "a_id": [ "cp5y24h" ], "score": [ 4 ], "text": [ "It's important to consider how the relative damage that, say, a bomber crashing into a neighbourhood would compare to the damage of an actual bomb dropping. \n\nIn general, planes being shot down and crashing into residential areas or factories w...
[]
[]
[ [] ]
bfvphf
why does the negative binary number system work the way it does
Like, for an 8-bit number storage, the bits, in order, represents -128, 64, 32, 16, 8, 4, 2, 1. Why isn’t the first number just a negative identifier and the bits would look like, (-), 64, 32, 16,...
explainlikeimfive
https://www.reddit.com/r/explainlikeimfive/comments/bfvphf/eli5_why_does_the_negative_binary_number_system/
{ "a_id": [ "elgpyrv", "elgya49" ], "score": [ 11, 2 ], "text": [ "There are a couple of different ways of representing negative numbers in binary. The easiest (for humans, anyways) one is called \"sign magnitude,\" and it's basically what you just described. One bit (the sign) denotes w...
[]
[]
[ [], [] ]
2oo5xt
When brakes are applied to an idling car, how come some gear doesn't break inside the drivetrain?
The engine is turning, the car isn't moving, what allows me to be stopped without some gear inside busting lose from torque?
askscience
http://www.reddit.com/r/askscience/comments/2oo5xt/when_brakes_are_applied_to_an_idling_car_how_come/
{ "a_id": [ "cmpolx6" ], "score": [ 2 ], "text": [ "If you're referring to an automatic transmission, the engine is connected to the drivetrain via a fluid coupling known as a torque converter. At low engine speeds, the torque converter is transmitting relatively low torque to the drivetrain which...
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[ [] ]
1w75ip
How accurate is the idea of feudal armies being comprised of conscripted peasants?
We are all aware of the trope of High Medieval armies being made in, in bulk, of farmers and masons with spears and low quality armour, but how accurate is that? How much of a feudal army would knights comprise? Searjeants? Town and city militia, professional mercenaries, and the aforementioned farmers and masons, how ...
AskHistorians
http://www.reddit.com/r/AskHistorians/comments/1w75ip/how_accurate_is_the_idea_of_feudal_armies_being/
{ "a_id": [ "cezdicz" ], "score": [ 28 ], "text": [ "Well, the period you're referring to saw some fairly dramatic changes, but there are enough similarities that we can speak at least a little in general terms. Instead of getting into the more complex questions, I'll try and do my best with the q...
[]
[]
[ [] ]
3tx4um
Based purely on the total number of people killed by people fighting in the name of each religion, which religion has historically been the most violent?
AskHistorians
https://www.reddit.com/r/AskHistorians/comments/3tx4um/based_purely_on_the_total_number_of_people_killed/
{ "a_id": [ "cx9zwj8" ], "score": [ 2 ], "text": [ "Sorry for my english i'm not a native speaker.\n\nThere is no precise answer to this question. However i'll provide a link toward a paper written by\n[Naveed s. Sheikh](_URL_0_) ( University of Louisville) where he tried to do an estimation. He a...
[]
[]
[ [ "https://www.keele.ac.uk/spire/staff/sheikh/", "https://docs.google.com/viewer?url=http://www.muslim-library.com/dl/books/English_Body_Count_a_quantitative_review_of_political_violence_across_world_civilizations_.pdf" ] ]
8mhf44
- why do people pick at scabs, fits, pimples, etc? we know it's bad and it hurts, but we still do it.
explainlikeimfive
https://www.reddit.com/r/explainlikeimfive/comments/8mhf44/eli5_why_do_people_pick_at_scabs_fits_pimples_etc/
{ "a_id": [ "dznl29q", "dznl9kd", "dznlahh" ], "score": [ 4, 3, 4 ], "text": [ "I don't have an answer for you but I can tell you that when I spent some time looking after some young baboons they also liked picking off my scabs when they were grooming.", "Because sometimes it w...
[]
[]
[ [], [], [] ]
3nnwx5
why is it that a large number of american students choose the high cost of their university over studying abroad?
[deleted]
explainlikeimfive
https://www.reddit.com/r/explainlikeimfive/comments/3nnwx5/eli5why_is_it_that_a_large_number_of_american/
{ "a_id": [ "cvpqtzm", "cvpr6wk", "cvprfcg", "cvprohg", "cvprxzb" ], "score": [ 13, 3, 7, 5, 2 ], "text": [ "If they can't afford a college education without loans, how are they going to afford studying abroad?", "It's usually more prestigious to come from an Am...
[]
[]
[ [], [], [], [], [] ]
1tkg7j
how are single grooves on lp's able to create such a vast array of different sounds, and all at once?
I understand the basics of it, that the stylus going along the groove creates a vibration which creates a sound, but that's about as far as it goes. I simply cannot get my head round how one groove, which can only either go left or right, can recreate any sound on earth, but not only that, any sound on earth, all at on...
explainlikeimfive
http://www.reddit.com/r/explainlikeimfive/comments/1tkg7j/eli5_how_are_single_grooves_on_lps_able_to_create/
{ "a_id": [ "ce8uoqz" ], "score": [ 5 ], "text": [ "Look at a speaker, if it's a buffer it will look more obvious. Play something at a relatively high volume if possible.\n\nSound is generated by the speaker moving back and forth and moving the air with it. On a buffer the movement is easier to se...
[]
[]
[ [ "http://en.wikipedia.org/wiki/File:Sine_and_Cosine.svg" ] ]
dvqy8q
brainfreezing when drinking something cold
explainlikeimfive
https://www.reddit.com/r/explainlikeimfive/comments/dvqy8q/eli5_brainfreezing_when_drinking_something_cold/
{ "a_id": [ "f7e5y3j", "f7eb8pu", "f7ebr4x", "f7eduag", "f7efb0i", "f7efdkk", "f7efryy", "f7egz16", "f7ehflb", "f7eip0i" ], "score": [ 507, 15, 4, 25, 10, 5, 3, 2, 2, 2 ], "text": [ "The mouth is situated really close to the b...
[]
[]
[ [], [], [], [], [], [], [], [], [], [] ]
1z8yn2
if a space elevator was built, would it get bent or flung out into space because of earth's rotation?
And what if a satellite or asteroid crashed into it? Would the whole thing come crashing down to the Earth?
explainlikeimfive
http://www.reddit.com/r/explainlikeimfive/comments/1z8yn2/eli5_if_a_space_elevator_was_built_would_it_get/
{ "a_id": [ "cfrlery", "cfrlkhc" ], "score": [ 2, 4 ], "text": [ "The idea is for the rotation of the Earth to try to fling it out into space. That would keep it standing since it would be anchored on Earth.", "It can't be done with current materials. There isn't anything strong enoug...
[]
[]
[ [], [] ]
1pf5eh
why don't inter-species friendships (e.g. cats and ferrets) occur in the wild?
explainlikeimfive
http://www.reddit.com/r/explainlikeimfive/comments/1pf5eh/eli5_why_dont_interspecies_friendships_eg_cats/
{ "a_id": [ "cd1noxi" ], "score": [ 4 ], "text": [ "They do it's just much more uncommon" ] }
[]
[]
[ [] ]
yphd0
what the treble does on sound devices, and how it relates to the bass
explainlikeimfive
http://www.reddit.com/r/explainlikeimfive/comments/yphd0/eli5_what_the_treble_does_on_sound_devices_and/
{ "a_id": [ "c5xnmxm", "c5xscmo" ], "score": [ 3, 2 ], "text": [ "treble is the opposite of bass. It's the higher frequencies in music, whereas bass is the low.\n\nELI5 - Bass is the low rumbling sounds in the music and treble is the higher pitched guitars and vocals (though most vocals ar...
[]
[]
[ [], [] ]
9ux1b8
can someone explain the american mid-term elections? (i'm european)
explainlikeimfive
https://www.reddit.com/r/explainlikeimfive/comments/9ux1b8/eli5_can_someone_explain_the_american_midterm/
{ "a_id": [ "e97p06y" ], "score": [ 2 ], "text": [ "Most of our national (Senate and House of Representatives) and local (governors, Judges, school board members) elections are held in two year intervals. Every four years, those elections coincide with the presidential election. \n\nIt's the same ...
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[ [] ]
2ub4b2
Are stem cells really that "next big thing" as advertised? Why or why not?
I don't really understand much about stem cell biology, only that it is very concentrated in the bone marrow, and that it can take the function of any other cell in the body. Is that it?
askscience
http://www.reddit.com/r/askscience/comments/2ub4b2/are_stem_cells_really_that_next_big_thing_as/
{ "a_id": [ "co6s5vx", "co6ttu7", "co6wapl", "co6wvq3", "co714o7", "co75n9x" ], "score": [ 11, 4, 3, 41, 23, 2 ], "text": [ "When a zygote is formed (i.e. when sperm and egg join) it divides over and over to form the cells that will eventually be the body of...
[]
[]
[ [ "http://en.wikipedia.org/wiki/Hematopoietic_stem_cell" ], [], [], [ "http://en.wikipedia.org/wiki/Mesenchymal_stem_cell", "http://stemcellstm.alphamedpress.org/site/misc/News159.xhtml", "http://newsroom.ucla.edu/releases/ucla-stem-cell-researcher-pioneers-gene-therapy-cure-for-children-wit...
2qb3gh
Why did the Germans not make a more concerted effort at breaking the blockade during World War I?
I've been watching the BBC's "The First World War" series from a couple of years back. They talked about how the German's made a single major attempt at breaking the Royal Navy blockade, and despite higher causalities on the British side, the German's were unable to break through. They went on to say that the Imperia...
AskHistorians
http://www.reddit.com/r/AskHistorians/comments/2qb3gh/why_did_the_germans_not_make_a_more_concerted/
{ "a_id": [ "cn4kuzq", "cn4olh1" ], "score": [ 7, 6 ], "text": [ "In order to effectively end the blockade it would not have been enough to just sink the ships patrolling between Norway and the UK. Trade would only have been possible if Germany somehow could secure shipping in the North Se...
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[]
[ [], [] ]
3e9tf5
what turns a "skin crease" into a "wrinkle" that stays there even when the reason for the crease (smiling, sitting a certain way, etc.) is gone?
I woke up today and noticed a wrinkle that was not there yesterday. What is the mechanism behind it becoming permanent seemingly overnight?
explainlikeimfive
http://www.reddit.com/r/explainlikeimfive/comments/3e9tf5/eli5_what_turns_a_skin_crease_into_a_wrinkle_that/
{ "a_id": [ "ctcxa71" ], "score": [ 3 ], "text": [ "Think of it like an elastic waistband. That thing can go a long time retaining its elasticity -- in my experience, ten, fifteen years. But eventually it hits that point where it's stretched too much. You pull to stretch, and it -- stays stretc...
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[]
[ [] ]
2r88xq
the technical difference between the rock-ish music genres: rock, metal, heavy metal, alternitive, grunge, etc.
explainlikeimfive
http://www.reddit.com/r/explainlikeimfive/comments/2r88xq/eli5the_technical_difference_between_the_rockish/
{ "a_id": [ "cnde601" ], "score": [ 3 ], "text": [ "_URL_0_\n\nKnock yourself out." ] }
[]
[]
[ [ "http://en.wikipedia.org/wiki/List_of_rock_genres" ] ]
2524zs
Why are some greenhouse gases more effective than others?
askscience
http://www.reddit.com/r/askscience/comments/2524zs/why_are_some_greenhouse_gases_more_effective_than/
{ "a_id": [ "chdeuyq" ], "score": [ 5 ], "text": [ "A greenhouse gas is just any (atmospheric) gas that primarily absorbs and emits radiation in the infrared region of the spectrum - and some are much better at doing this than others (i.e. they absorb/emit a greater range of infrared wavelengths)....
[]
[]
[ [ "http://en.wikipedia.org/wiki/Global-warming_potential" ] ]
23zft0
how are large computer files compressed into 1/4 of their size?
I purchased a physical copy of the game Titanfall, and when I installed it, the first DVD (7.95Gb) decompressed into 69% of the games installation, which amounted to 34.52Gb. I just don't understand how files could be compressed to being approximately 1/4 of their size. How are such large files compressed?
explainlikeimfive
http://www.reddit.com/r/explainlikeimfive/comments/23zft0/eli5_how_are_large_computer_files_compressed_into/
{ "a_id": [ "ch22x6l", "ch22xhq", "ch2751l", "ch2782c", "ch2fucs" ], "score": [ 3, 23, 2, 2, 2 ], "text": [ "Compression stores instructions on how to recreate the file rather than the file itself. So for an image for example, whereas an uncompressed bitmap might sa...
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[ [], [], [], [], [] ]
1ks0e7
Why do the planets nearer a star become rocky and those farther out become gas giants
Or is this not always a general make up of a system? It it's "generally but not always" true, have there been system discoveries of the opposite, with the gas giants in close and the rocky ones farther out?
askscience
http://www.reddit.com/r/askscience/comments/1ks0e7/why_do_the_planets_nearer_a_star_become_rocky_and/
{ "a_id": [ "cecequd" ], "score": [ 2 ], "text": [ "The actual reason for this is the frost line _URL_0_\n\nThe theory goes that inside the frost line, most light elements are fluid gasses, and thus tend to dissipate rather than coalesce (the thing required to start planetary formation). Because o...
[]
[]
[ [ "http://en.wikipedia.org/wiki/Frost_line_(astrophysics)" ] ]
41fkwe
why is tonight's democratic debate scheduled at the same time as a football game?
explainlikeimfive
https://www.reddit.com/r/explainlikeimfive/comments/41fkwe/eli5_why_is_tonights_democratic_debate_scheduled/
{ "a_id": [ "cz1y3ar", "cz1z6r0", "cz2knxn", "cz2x44d", "cz3fkng" ], "score": [ 45, 16, 2, 2, 2 ], "text": [ "Because the head of the DNC, Debbie Schultz, is strongly backing Hillary Clinton (she used to work for Hillary's previous campaigns) and she is of the opini...
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[]
[ [], [], [], [], [] ]
3w2rp5
how does a psychologist know what kind of thoughts are okay for their patients to have and what kind are not?
explainlikeimfive
https://www.reddit.com/r/explainlikeimfive/comments/3w2rp5/eli5_how_does_a_psychologist_know_what_kind_of/
{ "a_id": [ "cxstgqs", "cxsuh81", "cxsw2n1" ], "score": [ 4, 2, 3 ], "text": [ "They have a degree in studying the human psyche. Most of what a psychologist does is not to judge you based on an individual thought, but attempt to understand your thought process. \n\nFor instance, if...
[]
[]
[ [], [], [] ]
83wka3
Monday Methods: Sometimes you can't know everything – and why that's a good thing
Welcome to Monday Methods, a bi-weekly feature where we discuss, explain, and explore historical methods, historiography, and theoretical frameworks concerning history. Today, we will tackle a big question that dates back a very, very long time: What can we know? There is a whole field of philosophy attached to this q...
AskHistorians
https://www.reddit.com/r/AskHistorians/comments/83wka3/monday_methods_sometimes_you_cant_know_everything/
{ "a_id": [ "dvohkyu" ], "score": [ 8 ], "text": [ "Your post made me thinking - and maybe this would be better suited for a question - but I wonder if there is a specific approach for that transition period when the spread of literacy among a population takes place.\n\nWhile I have no academic fo...
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[ [] ]
2in75p
Why is superluminous communication not possible through the use of quantum entanglement in this thought experiment?
I propose the following experiment. * Suppose we generate a pair of quantum entangled particles - P1 and P2. * Beforehand we agree that I will measure the spin of P1 along the X axis, and you will measure the spin of P2 along the Y axis. * I receive P1, and you receive P2 at a different location. * I measure the spin ...
askscience
http://www.reddit.com/r/askscience/comments/2in75p/why_is_superluminous_communication_not_possible/
{ "a_id": [ "cl3q70o", "cl3qxt6" ], "score": [ 6, 9 ], "text": [ " > From the Heisenberg uncertainty principle follows that we cannot know the spin of the particle along two axes simultaneously.\n\nThat's not what the Heisenberg uncertainty principle says. The Heisenberg uncertainty princ...
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[ [], [] ]
1z1cn7
diesel engines.
I just purchased a 2003 VW Jetta TDi (NA model). I have a general understanding of normal petrol engines and have done basic wiring and maintenance to all of my previous vehicles: '94 Chevy 1500, 2004 Trailblazer, and 2007 Chevy 1500. Looking under the hood of my Jetta, I have no idea what is going on. I hear terms lik...
explainlikeimfive
http://www.reddit.com/r/explainlikeimfive/comments/1z1cn7/eli5_diesel_engines/
{ "a_id": [ "cfpmfb7", "cfpnnjq", "cfpnq3o" ], "score": [ 3, 3, 6 ], "text": [ "Some of this [information](_URL_0_) may be helpful. Sorry, I trade working on computers for other people working on my cars :)", "The main difference is that diesel fuel doesn't ignite from a spark ...
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[]
[ [ "http://www.google.com/#q=how+to+care+for+a+diesel+engine" ], [], [] ]
79wtj8
What is the most aerodynamic shape?
I can't seem to find a definitive answer as to which shape is the most aerodynamic. Everbody just says what aerodynamic shapes generally look like. I'm starting to wonder if it isn't actually proven what the most aerodynamic shape is. To clarify I'm asking, what shape with some width has the smallest drag coefficient.
askscience
https://www.reddit.com/r/askscience/comments/79wtj8/what_is_the_most_aerodynamic_shape/
{ "a_id": [ "dp644af" ], "score": [ 9 ], "text": [ "Well it depends on the operating speed.\n\nAerodynamic drag has 2 major components pressure drag and viscous drag. \nThese can be imagined in two cases. \n\nLets first consider a perfectly thin flat plate that is parallel to the direction of flow...
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[ [] ]
1fccn1
How much can we tell what a person looks like from a DNA sample, and how close are we to getting a complete picture of a person from that?
askscience
http://www.reddit.com/r/askscience/comments/1fccn1/how_much_can_we_tell_what_a_person_looks_like/
{ "a_id": [ "ca8w6ph", "ca8wbm0", "ca8yy6i" ], "score": [ 4, 2, 4 ], "text": [ "You can usually tell someone's race (that is, their geographic ancestral origin) with reasonable precision based on a genetic sample. I'm not sure if there are forensic databases correlating racial feat...
[]
[]
[ [], [], [ "http://en.wikipedia.org/wiki/Cape_verde", "http://www.plosgenetics.org/article/info%3Adoi%2F10.1371%2Fjournal.pgen.1003372", "http://www.nature.com/nature/journal/v467/n7317/full/nature09410.html", "http://www.sciencedirect.com/science/article/pii/S0002929711005337" ] ]
kofu6
Does anything evaporate with water?
I ask this question specifically with regards to [this product, the evaporation based water purification cone](_URL_0_), something that was posted on reddit a few days ago. The writer claims: > When you evaporate and condense water, the condensed water is 100% pure water. This means the purified water is complete...
askscience
http://www.reddit.com/r/askscience/comments/kofu6/does_anything_evaporate_with_water/
{ "a_id": [ "c2lvzxu", "c2lvzxu" ], "score": [ 3, 3 ], "text": [ "Anything with a vapor pressure equal to or greater than the vapor pressure of the water will carry over.\nEver drink distilled spirits? Whiskey, Vodka, etc? You evaporate off the alcohol, and some water to concentrate alcoho...
[]
[ "http://www.envirogadget.com/water-saving/evaporation-based-water-purifier-cone/" ]
[ [], [] ]
37w1br
What did native Americans on the coast of modern day California think about earthquakes?
AskHistorians
http://www.reddit.com/r/AskHistorians/comments/37w1br/what_did_native_americans_on_the_coast_of_modern/
{ "a_id": [ "crqkwo1" ], "score": [ 11 ], "text": [ "Alfred Kroeber recorded several Yurok stories that include earthquakes. A few can be found [here](_URL_0_). Some stories involve earthquakes as a moderating force between humans and non-humans (Woge, pronounced wah-gay), and between humans and ...
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[ [ "http://www.oac.cdlib.org/view?docId=hb7x0nb84s&brand=oac4&doc.view=entire_text", "http://www.angelfire.com/ia2/stories3/how.html" ] ]
18zln3
What was the average day like for a woman in ancient Greece? Specifically the Classical Era
AskHistorians
http://www.reddit.com/r/AskHistorians/comments/18zln3/what_was_the_average_day_like_for_a_woman_in/
{ "a_id": [ "c8jfr57", "c8jg54x" ], "score": [ 7, 6 ], "text": [ "The greater part of the population in Classical Greece were slaves; naturally this includes women. They therefore had no public face, no public or home life of their own, and no rights of any kind.\n\nHaving said that, femal...
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[ [], [] ]
15g4s8
if my phone is off, how does it know i pressed the button to turn it on?
Seriously. Its magic.
explainlikeimfive
http://www.reddit.com/r/explainlikeimfive/comments/15g4s8/if_my_phone_is_off_how_does_it_know_i_pressed_the/
{ "a_id": [ "c7m5ch4", "c7m6tc5", "c7md5oj" ], "score": [ 2, 16, 2 ], "text": [ "Much like many other devices requiring electronic signal, making a simple connection can actuate a signal to begin a startup process. \n \nThink of a light bulb and corresponding switch, or a car and i...
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[]
[ [], [], [] ]
1rdq3x
How much of a role did Herbert Hoover play in the Great Depression?
The people affected by the Depression blamed him so much as to call their cardboard boxes "Hoover Houses" but Harry Truman supposedly said that Hoover played no more role in the Depression than "you or I" (after campaigning that Hoover sucked in his election, but whatever). What specific policies of Hoover's can be dir...
AskHistorians
http://www.reddit.com/r/AskHistorians/comments/1rdq3x/how_much_of_a_role_did_herbert_hoover_play_in_the/
{ "a_id": [ "cdmnbir", "cdmqp50" ], "score": [ 6, 2 ], "text": [ "Herbert Hoover first and foremost believed in volunteerism and private charity. He did not encourage federal intervention whatsoever. He expected that the Great Depression (which wasn't considered that during Hoover's years ...
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[]
[ [ "http://herb.ashp.cuny.edu/items/show/1373", "http://www.trumanlibrary.org/hoover/world.htm", "http://www.nps.gov/nr/travel/presidents/herbert_hoover_nhs.html" ], [ "http://www.reddit.com/r/AskHistorians/comments/14ighq/what_caused_the_great_depression_to_be_so_severe/c7df0fz" ] ]
r64z7
Why does the ocean look vibrant blue/green in the tropics, but look grey up in the north Atlantic?
Just something I've noticed. Is it the temperature of the water? It looks much clearer the further south you go, too.
askscience
http://www.reddit.com/r/askscience/comments/r64z7/why_does_the_ocean_look_vibrant_bluegreen_in_the/
{ "a_id": [ "c437yul" ], "score": [ 2 ], "text": [ "Northern water looks murkier because there's more plankton in it. Southern water can't dissolve as much carbon dioxide or oxygen, since it's warmer, so not as much lives in it." ] }
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[ [] ]
39jmqw
Is there any evidence that suggests the universe is limited to the four dimensions we are aware of? Is there any evidence to the contrary?
I've been really curious about this for a while, especially after reading books like Flatland. Also, if anyone could recommend some nontechnical books to help me become more knowledgeable about spacetime and related phenomena, I would really appreciate it.
askscience
http://www.reddit.com/r/askscience/comments/39jmqw/is_there_any_evidence_that_suggests_the_universe/
{ "a_id": [ "cs47hnk" ], "score": [ 7 ], "text": [ "There are many theories out there that have built on Einstein's theory of four-dimensional spacetime. One of the most well-known is [string theory](_URL_2_), which comes in many varieties, each of which predicts more than four spacetime dimension...
[]
[]
[ [ "https://en.wikipedia.org/wiki/Introduction_to_M-theory", "http://home.web.cern.ch/about/physics/extra-dimensions-gravitons-and-tiny-black-holes", "https://en.wikipedia.org/wiki/String_theory" ] ]
4t0wmn
How long was an average trench during WWI?
Trenches in WWI were a massive thing, but just how massive were they?
AskHistorians
https://www.reddit.com/r/AskHistorians/comments/4t0wmn/how_long_was_an_average_trench_during_wwi/
{ "a_id": [ "d5dqmpb" ], "score": [ 2 ], "text": [ "The Western Front at it's most consistent, from December 1914 to March 1918, was about 540 miles in length. The Eastern Front was just over twice that length. Trench lines typically ran continuously for miles on end, and it was only in areas such...
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[]
[ [ "https://www.youtube.com/watch?v=2cbq7iu8FrI" ] ]
9dpeb1
how does the brain heal and get back past memories after a severe concussion?
[deleted]
explainlikeimfive
https://www.reddit.com/r/explainlikeimfive/comments/9dpeb1/eli5_how_does_the_brain_heal_and_get_back_past/
{ "a_id": [ "e5j96wg" ], "score": [ 3 ], "text": [ "Just wrote a long post about living with severe amnesia,.. you don't really get them back, and when you remember them it's like it's happening to someone else or you saw it on TV." ] }
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[ [] ]
1ei9o8
I have heard of some badass British Army regiments, but were any of them Irish?
Military buff here, and looking at British Army history there seems to be several examples of some pretty badass Scottish regiments (78th Highlanders at the Battle of Assaye, etc), but my question is are there any similar cases of Irish regiments being on the similar levels of badassery?
AskHistorians
http://www.reddit.com/r/AskHistorians/comments/1ei9o8/i_have_heard_of_some_badass_british_army/
{ "a_id": [ "ca15j17" ], "score": [ 2 ], "text": [ "Yeah, look into the Irish regiments during the Boer war. Queen Elizabeth herself decided that all Irish regiments should wear the Shamrock on St. Patricks day no matter where they are in the world in recognition of their bravery in the Boer wars....
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[ [ "http://en.wikipedia.org/wiki/Shamrock" ] ]
4ctznu
What do scientists mean and what does it look like when they say "equations break down"?
Whenever I hear a physicist or mathematician talk about some absurd thing or object, I sometimes hear them say "and at this point the equations break down". But how do they "break down"? What exactly does that mean and what does it look like?
askscience
https://www.reddit.com/r/askscience/comments/4ctznu/what_do_scientists_mean_and_what_does_it_look/
{ "a_id": [ "d1m16qb", "d1mc6d3" ], "score": [ 7, 4 ], "text": [ "Let's take a step back:\n\nScience is about creating models that both match natural phenomenon and predicts results as well. Science is **NOT** about explaining what is \"actually\" happening in the real world. This is a com...
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[ [], [] ]
2kgeoy
how is donation write-offs beneficial to people?
How does that process work? Is it done to get in a lower tax bracket? Inform me! Edit: are*
explainlikeimfive
http://www.reddit.com/r/explainlikeimfive/comments/2kgeoy/eli5_how_is_donation_writeoffs_beneficial_to/
{ "a_id": [ "cll1vac" ], "score": [ 7 ], "text": [ "I assume we are talking about claiming charitable donations on your taxes? It helps by incentivizing people to give their money to charity. \n\nSo lets say I pay 20% of my income in taxes but I can claim 100% of my charitable donations. If I g...
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[ [] ]
1gt8bt
How do present day Germans feel about WW1 and WW2?
AskHistorians
http://www.reddit.com/r/AskHistorians/comments/1gt8bt/how_do_present_day_germans_feel_about_ww1_and_ww2/
{ "a_id": [ "canktk4" ], "score": [ 2 ], "text": [ "We're historians and we can't really answer questions on current day events. For example, had you asked us how Germans in the 60's and 70's felt about the two world wars, then it would have been something we could have answered. I would recommend...
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[ [] ]
nwn6b
I read somewhere that in intergalactic space, it's a pitch dark void, is this true?
I don't understand how we would be able to see galaxies from within our galaxy, but not between them.
askscience
http://www.reddit.com/r/askscience/comments/nwn6b/i_read_somewhere_that_in_intergalactic_space_its/
{ "a_id": [ "c3cjfto", "c3cjfto" ], "score": [ 2, 2 ], "text": [ "See [this thread](_URL_0_) from earlier today: lots of answers there, some of them even good. None put exact figures on light levels in intergalactic space, unfortunately.\n\nThe upshot is: if you were within a couple of mil...
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[]
[ [ "http://www.reddit.com/r/askscience/comments/nw54j/if_a_man_was_out_in_deep_space_would_there_be/" ], [ "http://www.reddit.com/r/askscience/comments/nw54j/if_a_man_was_out_in_deep_space_would_there_be/" ] ]
2158ku
How much emphasis was placed on continued ability in hand-to-hand/close quarters combat during the rise of gunpower?
Given the difficulty and lengthy process of reloading a gunpowder firearm, it would seem like having proficiency in traditional fighting techniques would remain a crucial part of military training. Did the rise of gunpowder shift the traditional battle formation so drastically that men were no longer expected to engag...
AskHistorians
http://www.reddit.com/r/AskHistorians/comments/2158ku/how_much_emphasis_was_placed_on_continued_ability/
{ "a_id": [ "cg9tm9c" ], "score": [ 4 ], "text": [ "This is a long, long period of history you're asking about here. I think it's best separated into before and after the development of the socket bayonet (the late 17th century). I'm most familiar with warfare before that development, so I'll focu...
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[ [] ]
qo1th
Is it possible to temporarily demagnetize a "hard" magnet?
I'm aware one can create a simple electromagnet with a ferrous material and current, but what about the *opposite*. Is it possible to demagnetize a powerful "hard" magnet temporarily?
askscience
http://www.reddit.com/r/askscience/comments/qo1th/is_it_possible_to_temporarily_demagnetize_a_hard/
{ "a_id": [ "c3z5moe", "c3z772r" ], "score": [ 2, 2 ], "text": [ "If you heat a magnet up enough it will demagnetize temporarily (or maybe permanently depending on the material it is made of and how it cools).", "Here's a clever device that effectively allows you to turn a permanent ma...
[]
[]
[ [], [ "http://en.m.wikipedia.org/wiki/Magnetic_base" ] ]
advig8
how do we make things cold?
[deleted]
explainlikeimfive
https://www.reddit.com/r/explainlikeimfive/comments/advig8/eli5_how_do_we_make_things_cold/
{ "a_id": [ "edkegag", "edkem8x", "edkeql4", "edkes78" ], "score": [ 2, 38, 2, 7 ], "text": [ "Temperature, pressure and volume is related. If we force a gas into a smaller volume its pressure increases, and as its pressure increases its temperature increases. If we allowed...
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[]
[ [], [], [], [] ]
7uajoo
Lee Harvey Oswald had defected to the Soviet Union in the late 1950s. Is this as unusual as it sounds, for the time? Why wasn't a bigger deal made of it after the Kennedy assassination?
AskHistorians
https://www.reddit.com/r/AskHistorians/comments/7uajoo/lee_harvey_oswald_had_defected_to_the_soviet/
{ "a_id": [ "dtjfw66" ], "score": [ 17 ], "text": [ "I don't have any data relating to the numbers of Americans who defected to the USSR during the Cold War, so hopefully another contributor will come in with some information on that, but I am somewhat confused as to your suggestion that Oswald's ...
[]
[]
[ [ "http://digitalarchive.wilsoncenter.org/document/119369", "http://digitalarchive.wilsoncenter.org/document/119382", "https://www.reddit.com/r/AskHistorians/comments/55wy6r/jfk_was_assassinated_on_nov_22_1963_the_united/", "http://digitalarchive.wilsoncenter.org/document/119368", "http://query....
1y834p
why gwyneth paltrow is one of the most hated celebrities
Besides being married to a Thom Yorke wannabe, what's wrong with Gwyneth?
explainlikeimfive
http://www.reddit.com/r/explainlikeimfive/comments/1y834p/eli5_why_gwyneth_paltrow_is_one_of_the_most_hated/
{ "a_id": [ "cfi690i", "cfi6smy" ], "score": [ 6, 14 ], "text": [ "She's hated? First I've heard of it.\n\nSource?", "Many people believe that she's rich, snobbish, elitist, and out of touch with average people. She came from money, enjoyed success in Hollywood, and married someone ri...
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[]
[ [], [] ]
z6m0t
What happens to muscle mass that is gained through exercise, when you stop exercising?
I've heard it turns to fat, however turning proteins to lipids doesn't seem plausible, so what happens? For the sake of a case study, let's imagine a body builder of ten years quits exercising. What happens to their muscles?
askscience
http://www.reddit.com/r/askscience/comments/z6m0t/what_happens_to_muscle_mass_that_is_gained/
{ "a_id": [ "c61x54v", "c61x5ub", "c61xi17", "c61xwzq", "c61xyag", "c6212p6", "c625tha" ], "score": [ 3, 65, 366, 22, 26, 6, 2 ], "text": [ "It \"atrophies\". Basically, your body breaks it down because you don't need it anymore(you aren't exerting y...
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[]
[ [], [], [ "http://nutsci.org/2010/08/23/muscle-memory-its-in-the-myonuclei/" ], [], [], [], [] ]
24eodn
Can you melt any substance?
I know it sounds ludicrous, but they always say that water is the only substance that can be three states of matter on this planet naturally, but is it possible to melt everyday objects if it were hot enough? For instance wood, if you got it hotter that it would need to catch fire and burn, could you somehow make it in...
askscience
http://www.reddit.com/r/askscience/comments/24eodn/can_you_melt_any_substance/
{ "a_id": [ "ch6g8xa", "ch6dx8w", "ch6e0sk" ], "score": [ 7, 7, 19 ], "text": [ "Try a [quick search](_URL_0_) in the future to see past threads.", "A lot of solids decompose before melting: this means they change their chemical composition because they are not stable enough at...
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[ [ "http://www.reddit.com/r/askscience/search?q=melt+wood&restrict_sr=on" ], [], [ "http://www.kentchemistry.com/images/links/matter/Phase.gif" ] ]
98febg
How much of a problem is space debris for the ISS and shuttles?
askscience
https://www.reddit.com/r/askscience/comments/98febg/how_much_of_a_problem_is_space_debris_for_the_iss/
{ "a_id": [ "e4fn6mm", "e4fng7u", "e4h98aj" ], "score": [ 17, 8, 14 ], "text": [ "There are no more space shuttles, but for the ISS and other spacecraft, the answer is space debris is a potential hazard, but fairly easily managed. NASA and the DoD track tens of thousands of pieces ...
[]
[]
[ [], [ "https://www.space.com/20925-space-station-bullet-hole-photo.html" ], [ "https://www.nasaspaceflight.com/2014/07/iss-managers-evaluating-mmod-radiator/" ] ]
2vuw43
When a snake swallows an animal whole, what actually kills the animal? Does it suffocate, or does it die from being exposed to the snake's gastric acids or something else?
askscience
http://www.reddit.com/r/askscience/comments/2vuw43/when_a_snake_swallows_an_animal_whole_what/
{ "a_id": [ "colbpdy", "coldnzp", "coli2zd" ], "score": [ 6, 8, 3 ], "text": [ "Not a biologist but pretty sure it's constriction that asphyxiates the animal as well as crushing bones and causing internal injuries. Used to have a few. Snakes and watched them kill a few things. Th...
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[]
[ [], [], [] ]
62uvpq
Do some people burn more calories performing mental tasks than others performing those same tasks? Given they both have the same experience or knowledge of the subject?
askscience
https://www.reddit.com/r/askscience/comments/62uvpq/do_some_people_burn_more_calories_performing/
{ "a_id": [ "dfqbgc3" ], "score": [ 4 ], "text": [ "Last time calorie burning by the brain was brought up,a brain at rest and a brain thinking hard burns the same number of calories. That question was asked by some one wondering why we felt tired after exams and hours of concentration. \n\nThe stu...
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[ [] ]
5lxq7q
What is the relationship between a photon's spin and polarization?
I've been told that a photon's spin vector is ultimately measuring the same thing as the electric and magnetic ripples it creates but I can't figure out the mathematical relationship. Spin is measured in units of angular momentum while electric and magnetic potential have their own units. Is there a simple equation th...
askscience
https://www.reddit.com/r/askscience/comments/5lxq7q/what_is_the_relationship_between_a_photons_spin/
{ "a_id": [ "dbznlkq" ], "score": [ 8 ], "text": [ "Light has two types of angular momentum: spin and orbital (SAM and OAM). They can be represented by the equations [here](_URL_0_).\n\nSAM is explained by the circularity of the light's polarization. If you have a plane wave of light where the pol...
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[]
[ [ "https://en.wikipedia.org/wiki/Angular_momentum_of_light#Mathematical_expressions_for_the_angular_momentum_of_light", "https://www.researchgate.net/figure/227399224_fig1_FIG-2-Transverse-profile-of-fundamental-Gaussian-beam-l-0-and-Laguerre-Gaussian" ] ]
69bl3z
gel electrophoresis, i have a bio test tomorrow.
explainlikeimfive
https://www.reddit.com/r/explainlikeimfive/comments/69bl3z/elif_gel_electrophoresis_i_have_a_bio_test/
{ "a_id": [ "dh5b81y" ], "score": [ 2 ], "text": [ "Depending on the pH, most biomolecules have a charge. When placed in an electric field, those molecules will try to migrate towards the electrode with the opposite charge of the biomolecule.\n\nNow, if you place indentations into a gel (like agar...
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[ [] ]
8osu0b
weather anomaly in arctic canada: why has it been colder than normal while the rest of the country will be warmer above normal? again.
We will have another colder than usual summer while the rest of the country will be above normal. Why the anomaly? _URL_0_
explainlikeimfive
https://www.reddit.com/r/explainlikeimfive/comments/8osu0b/eli5_weather_anomaly_in_arctic_canada_why_has_it/
{ "a_id": [ "e062k04" ], "score": [ 4 ], "text": [ "Temp also has a lot to do with air currents. A wind pushes hot air from south america into the US during winter and we get a record high temp in february. A wind current that would normally blow south could have decided to stop and blow back tow...
[]
[ "https://weather.gc.ca/saisons/image_e.html?img=s123pfe1t_cal_comb" ]
[ [] ]
1pu6ok
Was the fall of the Soviet Union expected, or a surprise?
Did the United States expect the Soviet Union to fall when it did? If I remember correctly, an attempted coup on Gorbachev was the catalyst; but did the U.S have experts predicting that it would fall in x years?
AskHistorians
http://www.reddit.com/r/AskHistorians/comments/1pu6ok/was_the_fall_of_the_soviet_union_expected_or_a/
{ "a_id": [ "cd67d5c" ], "score": [ 29 ], "text": [ "I heard Ambassador Matlock speak recently (American Ambassador to the USSR from 1987-1991) and he said that the American diplomatic corps was actually discussing the imminent collapse with their Soviet counterparts back into 1988. He referenced ...
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[ [] ]
1pkqly
What inspired the Romans to keep such good records of their history?
When I think of history, I think of Herodotus, Thucydides, and the Romans - Plutarch, Polybius, etc. Was it a Greek influence? Did the Gauls and other peoples keep such comprehensive and artistic histories that weren't isolated to oratory?
AskHistorians
http://www.reddit.com/r/AskHistorians/comments/1pkqly/what_inspired_the_romans_to_keep_such_good/
{ "a_id": [ "cd3g0lk" ], "score": [ 4 ], "text": [ "Each of the ancient historians would have their own reasons to write about Roman history. One reason that has been touched upon by some of my friends is how Roman culture demanded that you do something with your time, and for some, writing histor...
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[]
[ [] ]
mmxk0
What is the minimum mass required for a celestial object to become spherical in shape?
Moons, planets, and stars are usually spheres and many asteroids tend to be big rocks. How massive does an object have to be before nature makes it a sphere? And why do large masses become spherical?
askscience
http://www.reddit.com/r/askscience/comments/mmxk0/what_is_the_minimum_mass_required_for_a_celestial/
{ "a_id": [ "c327ldf", "c327omm", "c327ldf", "c327omm" ], "score": [ 7, 2, 7, 2 ], "text": [ "AFAIK the smallest *round* moon in the solar system is Mimas (about 3.8 x 10^19 kg), although it slightly tidally distorted ovoid by Saturn's gravity.\n\n > Planets are round becau...
[]
[]
[ [ "http://www.scientificamerican.com/article.cfm?id=why-are-planets-round" ], [], [ "http://www.scientificamerican.com/article.cfm?id=why-are-planets-round" ], [] ]
a3s36t
how come roadways aren't filled with tire dust if over time, tires become worn out?
explainlikeimfive
https://www.reddit.com/r/explainlikeimfive/comments/a3s36t/eli5_how_come_roadways_arent_filled_with_tire/
{ "a_id": [ "eb8n3j3", "eb8srt1" ], "score": [ 3, 2 ], "text": [ "Tire dust is very light. It blows easily in the wind and it is actually a significant portion of air pollution in cities. It can also be partially melted (such as skid marks from rabid breaking) and will stain the road black...
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[]
[ [], [] ]
22xg2y
how does a store like game make profit on selling a 20 dollar steam card for 20 dollars?
explainlikeimfive
http://www.reddit.com/r/explainlikeimfive/comments/22xg2y/eli5_how_does_a_store_like_game_make_profit_on/
{ "a_id": [ "cgrbxow", "cgrivvm" ], "score": [ 3, 2 ], "text": [ "They buy them for less than $20", "This is essentially referral marketing. The store attracts a mass of consumers, Steam gives the store a portion of the profits for directing the consumers to them. In this case you don'...
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[]
[ [], [] ]
wnbky
How many dictators has the US supported throughout history?
My knowledge only extends back to the start of the cold war, but these are the ones I know: Marcos Noriega Suharto Mobutu Duvalier Trujillo Reza Shah What am I missing?
AskHistorians
http://www.reddit.com/r/AskHistorians/comments/wnbky/how_many_dictators_has_the_us_supported/
{ "a_id": [ "c5es8ls", "c5esy36", "c5etg23", "c5eul3h", "c5evgep", "c5eykpm", "c5ezo7g" ], "score": [ 2, 15, 8, 4, 2, 2, 4 ], "text": [ "The United States has a long tradition of backing friendly dictators in Latin American and the Caribbean. \n\nAnd...
[]
[]
[ [], [], [ "http://www.foreignpolicy.com/articles/2011/10/28/america_unsavory_allies" ], [], [ "http://en.wikipedia.org/wiki/Operation_Condor" ], [], [] ]
2j2fl9
the relationship between radiation particles and the electromagnetic spectrum
I'm generally aware of the electromagnetic spectrum, how it goes from infrared to visible light, to ultraviolet and then x-rays, etc. Also I'm generally aware of "radioactive particles" such as alpha particles, beta particles, and gamma particles. However I was thinking about it, and I realized I don't know what thes...
explainlikeimfive
http://www.reddit.com/r/explainlikeimfive/comments/2j2fl9/eli5_the_relationship_between_radiation_particles/
{ "a_id": [ "cl7raqk", "cl7revd" ], "score": [ 2, 2 ], "text": [ "Alpha particles are 2 protons and 2 neutrons, basically the nucleus of a helium-4 atom. Beta particles are electrons. Gamma particles (or gamma rays) are photons at an energy level above x-rays.", "The particles emitted ...
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[]
[ [], [] ]
2t49ha
what would happen if china decided to stop producing consumer goods?
I'm always seeing "Made in China" What would happen if they suddenly stopped, with no notice to anyone?
explainlikeimfive
http://www.reddit.com/r/explainlikeimfive/comments/2t49ha/eli5_what_would_happen_if_china_decided_to_stop/
{ "a_id": [ "cnvk08x" ], "score": [ 6 ], "text": [ "China's entire economy would collapse, t shirts would triple in price.\n\n" ] }
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[ [] ]
220v5z
Are there any records of the initial exposure of Europeans to new world foods?
I recall reading that the first waves of Europeans hated cranberries and tried to make tea out of Jimson weed, and hilarity ensued. I don't remember where I read this, but the idea that some people experimented in this way and wrote down the results is fascinating. I'd love to get more information.
AskHistorians
http://www.reddit.com/r/AskHistorians/comments/220v5z/are_there_any_records_of_the_initial_exposure_of/
{ "a_id": [ "cgin7tj", "cginkx7", "cgio0ok" ], "score": [ 54, 8, 19 ], "text": [ "Rebecca Earle has an excellent book on this subject called [The Body of the Conquistador](_URL_0_). The main thrust of her argument is that the ways in which sixteenth century Europeans, and Spaniards...
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[ [ "http://www.amazon.com/The-Body-Conquistador-Experience-Perspectives/dp/1107693292/ref=sr_1_1?ie=UTF8&qid=1396483195&sr=8-1&keywords=body+of+the+conquistador" ], [], [] ]
5z2vw4
how is it possible for the internet archive's wayback machine to store copies of so many websites?
I know they have several datacenters, but as of 2014 they had stored copies of over 400 billion web pages. How can one organization store such a mind-boggling amount of data?
explainlikeimfive
https://www.reddit.com/r/explainlikeimfive/comments/5z2vw4/eli5_how_is_it_possible_for_the_internet_archives/
{ "a_id": [ "deuv2ph", "deuveex", "deuxqjw" ], "score": [ 3, 5, 3 ], "text": [ "The files that make up most websites are tiny. I used to build sites and the actual programming just takes no real storage space to speak of. Pictures are another story but with compression their also p...
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[]
[ [], [], [] ]
rr9te
Why are the properties of plastics so varied?
So I'm guessing plastics are pretty similar at the molecular level at least having more in common with each other than with metals or salts. So, why is there such a variety in properties (strong, soft, brittle, elastic...)? What do brittle plastics have in common and how are they different to elastic plastics?
askscience
http://www.reddit.com/r/askscience/comments/rr9te/why_are_the_properties_of_plastics_so_varied/
{ "a_id": [ "c4806f2", "c480ac5", "c480h51", "c480sb3", "c4825hh" ], "score": [ 5, 13, 3, 46, 2 ], "text": [ "The key with plastics is that they are polymeric chains. This means that you can have plastics of very similar molecular formula on paper, but the manufact...
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[]
[ [], [ "http://en.wikipedia.org/wiki/Kapton", "http://en.wikipedia.org/wiki/Polyethylene", "http://en.wikipedia.org/wiki/Teflon" ], [], [ "http://en.wikipedia.org/wiki/Polypropylene", "http://en.wikipedia.org/wiki/Stress_intensity_factor", "http://en.wikipedia.org/wiki/Polyethylene", ...
42czod
How were mestizos treated in New Spain?
AskHistorians
https://www.reddit.com/r/AskHistorians/comments/42czod/how_were_mestizos_treated_in_new_spain/
{ "a_id": [ "cz9d2xs" ], "score": [ 6 ], "text": [ "That depends, at what point in time are you wondering about? A mestizo in 1540 would not be treated the same as a mestizo in 1640, 1740, or 1840." ] }
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[ [] ]
ztx36
If you mix drops of blood from two people, could you tell with just the naked eye if their blood types match?
So I guess my real question is, could you see the blood agglutinate (clump) without a microscope?
askscience
http://www.reddit.com/r/askscience/comments/ztx36/if_you_mix_drops_of_blood_from_two_people_could/
{ "a_id": [ "c67p0xf", "c67pmwz", "c67tuiw" ], "score": [ 2, 39, 6 ], "text": [ "If you have the proper card, you can test each kind visually:\n\n_URL_0_\n\nBut I don't know about combining them, sorry.", "Yes you can. The blood will clot at a macroscopic level (aka visible to ...
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[]
[ [ "http://en.wikipedia.org/wiki/Hemagglutinin" ], [], [ "http://www.austincc.edu/mlt/bb/Grading%20Agglutination%20Reactions.jpg" ] ]
34bupt
what causes the "8 bit" style sound that old video games had.
Why do old video games have a distinct type of sound to them, and what made it go away?
explainlikeimfive
http://www.reddit.com/r/explainlikeimfive/comments/34bupt/eli5_what_causes_the_8_bit_style_sound_that_old/
{ "a_id": [ "cqt69dr", "cqt6jhl", "cqt9av0", "cqtiwvi" ], "score": [ 4, 6, 2, 2 ], "text": [ "Each system had its own dedicated sound processor, and they weren't terribly powerful. The sound processors each had distinctive sounds that we look back on with nostalgia. Nowaday...
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[]
[ [], [ "http://onlinetonegenerator.com/" ], [], [ "https://www.youtube.com/watch?v=4HWHneafZ8w", "https://www.youtube.com/watch?v=la3coK5pq5w" ] ]
411jqv
How does physical manipulation (e.g. massage) relax muscles? Does pressure create physiological changes in the tissue?
Maybe another way to put this might be: How much of muscle relaxation is physiological and how much is psychological? **Edit:** Please provide credible sources if possible. Perhaps understandably, this field is full of personal theories without scientific support, so if you could provide links to appropriate sources ...
askscience
https://www.reddit.com/r/askscience/comments/411jqv/how_does_physical_manipulation_eg_massage_relax/
{ "a_id": [ "cyz0ege", "cyz3sqg", "cyz6fzk", "cyza15u", "cyza1js", "cyzahoj", "cyzs8cj" ], "score": [ 786, 7, 200, 25, 11, 19, 2 ], "text": [ "Stimulation of mechanoreceptors in the skin/muscle/fascia tissue can also activate inhibitory interneurons ...
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[]
[ [], [], [ "https://www.researchgate.net/figure/8004036_fig2_Figure-9-Theoretical-model-of-the-expected-mechanisms-of-massage-on-the-severity-of", "https://en.wikipedia.org/wiki/Muscle_spindle", "http://www.ncbi.nlm.nih.gov/pubmed/15730338" ], [], [], [], [] ]
4y6zh4
why, if we are searching for something, can we not seem to see it even if we are looking right at it?
explainlikeimfive
https://www.reddit.com/r/explainlikeimfive/comments/4y6zh4/eli5_why_if_we_are_searching_for_something_can_we/
{ "a_id": [ "d6lhki1", "d6lih2c", "d6lkhj0", "d6lm4vl", "d6lmnq4", "d6lmrd5", "d6lz312" ], "score": [ 112, 12, 2, 6, 4, 2, 2 ], "text": [ "These are all excellent answers, but i think it's mostly attention fatigue and familiarity. You know how in Jur...
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[ [], [], [], [], [], [], [] ]
akd27n
does popcorn pop for a reason? did it develop that ability to procreate itself, or are there any other reasons?
[deleted]
explainlikeimfive
https://www.reddit.com/r/explainlikeimfive/comments/akd27n/eli5_does_popcorn_pop_for_a_reason_did_it_develop/
{ "a_id": [ "ef3twsm" ], "score": [ 4 ], "text": [ "It's just what happens when it's cooked. It's not for the benefit of the plant. It pops because the water held inside of the corn kernel vaporizer and explodes. Other grains puff up when cooked. Think about rice crispys. It's puffed rice...
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[ [] ]
2kua2n
Why does infrared light appear as white on my cell phone camera?
I tried pointing a remote at my cell phone camera, and the result is a seemingly white flash. Intuitively, I would have guessed that it would show up as red (if anything). Why does infrared seemingly light up the blue and green sensors, unlike the chromatically closer red light (which outputs just red light)?
askscience
http://www.reddit.com/r/askscience/comments/2kua2n/why_does_infrared_light_appear_as_white_on_my/
{ "a_id": [ "clp0syj" ], "score": [ 18 ], "text": [ "Most digital camera sensors are actually monochrome! They have a special filter called [Bayer filter](_URL_0_) on top of them, so that each photosite (sensor \"pixel\") receives either red, green, or blue filtered light. The missing color inform...
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[ [ "http://en.wikipedia.org/wiki/Bayer_filter" ] ]
7pofeu
How did the French conquer Vietnam?
Considering the fact that Vietnam was able to, more or less, defeat both France and the United States in the twentieth century and that the region has a strong tradition of defending against foreign invasions, how was the French originally able to conquer Vietnam during the age of imperialism? Why was France able to be...
AskHistorians
https://www.reddit.com/r/AskHistorians/comments/7pofeu/how_did_the_french_conquer_vietnam/
{ "a_id": [ "dspqcwu" ], "score": [ 2 ], "text": [ "It's because after the French helped the Southern Vietnamese establish the Nguyen dynasty under Emperor Gia Long, the next successors however decided to close off Vietnam to trading with foreign nations including the French who used to supply the...
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[ [] ]
zl2tc
how does scientology "hook" a superstar like cruise? what does he get out of it?
explainlikeimfive
http://www.reddit.com/r/explainlikeimfive/comments/zl2tc/eli5_how_does_scientology_hook_a_superstar_like/
{ "a_id": [ "c65jwcy", "c65ludk" ], "score": [ 2, 2 ], "text": [ "Do those guys actually believe the whole xenu thing?", "Not a complete answer to the question, but there was a theory floating around a while ago that the reason Scientology was so appealing to celebrities in particular ...
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[ [], [] ]
773got
In a neutron, is it possible for the up quark to decay into a down quark?
If it's possible would the charge be -1 since down quarks have a charge of -1/3(as far as I know)?
askscience
https://www.reddit.com/r/askscience/comments/773got/in_a_neutron_is_it_possible_for_the_up_quark_to/
{ "a_id": [ "doit70w" ], "score": [ 15 ], "text": [ "All hadrons made of three down quarks have higher mass than a neutron, so this cannot happen spontaneously as a decay. You have to put in a lot of energy to make this happen in a reaction." ] }
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[ [] ]
9byu67
is more heat generated by air conditioning than cold air except that the cold air just goes where we want it?
explainlikeimfive
https://www.reddit.com/r/explainlikeimfive/comments/9byu67/eli5_is_more_heat_generated_by_air_conditioning/
{ "a_id": [ "e56rd5n", "e56rojz" ], "score": [ 9, 6 ], "text": [ "That's correct. Air conditioners don't generate cold at all. They are *heat pumps* that move the heat out of your room and into the outdoor air. And the actually create some more heat in the process.", "Yes. Moreover, yo...
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[ [], [] ]
9ec5wl
why are three letter acronyms so common in english?
Is it related to English sentence / noun structure. Do you find three letter acronyms in other languages?
explainlikeimfive
https://www.reddit.com/r/explainlikeimfive/comments/9ec5wl/eli5_why_are_three_letter_acronyms_so_common_in/
{ "a_id": [ "e5nqkuq", "e5nrdkb", "e5ow8rs" ], "score": [ 10, 3, 3 ], "text": [ "Let me fix that for you.\n\nWhy are TLAs so common in English?", "Because they are used a lot and happen to sound pretty good as well. So instead of typing i'm laughing out loud, you use lol instea...
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[ [], [], [] ]
6b1597
Were treasure maps a real thing?
If they were, wouldn't that just invite people to steal your treasure?
AskHistorians
https://www.reddit.com/r/AskHistorians/comments/6b1597/were_treasure_maps_a_real_thing/
{ "a_id": [ "dhjgqzs" ], "score": [ 3 ], "text": [ "Not to discourage other answers, but check out /u/Theamazinghanna's answer in [this post](_URL_0_). It's old, but the answer is pretty solid.\n\nThere's also a ton of interesting piracy related topics in the FAQ under [Piracy](_URL_1_).\n\nI hope...
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[]
[ [ "https://www.reddit.com/r/AskHistorians/comments/18aai1/how_frequently_if_ever_did_pirates_actually_bury/", "https://www.reddit.com/r/AskHistorians/wiki/dailylife#wiki_piracy" ] ]
5003d2
why in a firefight does the side that has the upper ground have the advantage?
explainlikeimfive
https://www.reddit.com/r/explainlikeimfive/comments/5003d2/eli5why_in_a_firefight_does_the_side_that_has_the/
{ "a_id": [ "d7037ae", "d703fsg", "d7058j0" ], "score": [ 2, 23, 2 ], "text": [ "Because they are less exposed than the enemy. It is hard to fortify yourself, when someone is looking down out you. It also allows you to have a larger vantage point of the surrounding area, and was a ...
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[ [], [], [] ]
65e2w0
Why does a galaxy not form clusters of stars similar to planets?
Assuming a spiral galaxy, why do we not see large groups of gravitationally bound stars orbiting the center like a planet? Instead we see spiral Arms, not spherical clumps.
askscience
https://www.reddit.com/r/askscience/comments/65e2w0/why_does_a_galaxy_not_form_clusters_of_stars/
{ "a_id": [ "dg9je2v" ], "score": [ 3 ], "text": [ "Galaxies do form [star clusters!](_URL_1_) There are two main types, open (like the [Pleiades](_URL_1_#/media/File:M45_filip.jpg)) and globular (like [M 68](_URL_0_)). However, these are on much smaller scales compared to the spiral arm. " ] }
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[]
[ [ "https://en.wikipedia.org/wiki/Star_cluster#/media/File:A_Ten_Billion_Year_Stellar_Dance.jpg", "https://en.wikipedia.org/wiki/Star_cluster", "https://en.wikipedia.org/wiki/Star_cluster#/media/File:M45_filip.jpg" ] ]
8jqy5x
in a ponzi scheme, how is it not obvious that you are not receiving any money from your investments?
explainlikeimfive
https://www.reddit.com/r/explainlikeimfive/comments/8jqy5x/eli5_in_a_ponzi_scheme_how_is_it_not_obvious_that/
{ "a_id": [ "dz1rvw2", "dz1rx12", "dz1s5n4" ], "score": [ 2, 16, 6 ], "text": [ "The “fund managers” are responsible for the investments, so they can tell you that your investment went into company A and company B, producing X returns. In actual fact they did nothing with the money...
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[ [], [], [] ]
4cr9ht
How much did Cromwell and the subsequent Glorious Revolution contribute to the ideology of Democracy in general?
[deleted]
AskHistorians
https://www.reddit.com/r/AskHistorians/comments/4cr9ht/how_much_did_cromwell_and_the_subsequent_glorious/
{ "a_id": [ "d1kwm0p" ], "score": [ 4 ], "text": [ "I can't really speak to the impact of the Glorious Revolution - my focus is the English Civil Wars (my pedigree btw: MA thesis *London in the Civil Wars ... Blah blah... Tower of London* BA thesis *English Radical Politics and Piracy*) - but as t...
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[ [ "http://bcw-project.org/church-and-state/second-civil-war/prides-purge", "http://bcw-project.org/church-and-state/second-civil-war/putney-debates", "http://bcw-project.org/church-and-state/the-commonwealth/nominated-assembly" ] ]
4sl3dn
How do fans dry people?
Like when I take a shower, if I sit next to an electric fan, it dries me very fast, but it's spitting out cold air. Similar to air-driers from bathrooms
askscience
https://www.reddit.com/r/askscience/comments/4sl3dn/how_do_fans_dry_people/
{ "a_id": [ "d5a88zn" ], "score": [ 7 ], "text": [ "Evaporation rates depend on the saturation of water vapor in the air above the liquid. When the air is not moving, the air nearest to the water becomes humid quickly and it takes time for it to diffuse away allowing more evaporation.\n\nWhen you ...
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[ [] ]
2y374m
What do we know about the rural population of Germany during World War 2?
AskHistorians
http://www.reddit.com/r/AskHistorians/comments/2y374m/what_do_we_know_about_the_rural_population_of/
{ "a_id": [ "cp641kt" ], "score": [ 12 ], "text": [ "What are you interested in? \nThey were often better off, as they could rely on their own agricultural production, although this was heavily regulated. Illiegal butchering was considered a serious crime, but records show that it was practised ...
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[ [] ]
34yy0v
If scientists knew NOTHING about a caterpillar, could they tell it had the potential to turn into a butterfly by dissection alone?
Or even through observation of behavior, so long as they never saw it perform the metamorphosis, could they tell it was part of their make up?
askscience
http://www.reddit.com/r/askscience/comments/34yy0v/if_scientists_knew_nothing_about_a_caterpillar/
{ "a_id": [ "cr01bbq", "cr1qevj" ], "score": [ 5, 2 ], "text": [ "There's a David Attenborough series called Natural Curiosities which has an episode that covers this exact topic! It's a really lovely series so I recommend it to anyone looking for a pleasant and interesting half-hour.\n\nT...
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[ [], [] ]
aigs1m
why do ethics outweigh the benefits when it comes to genetic engineering of humans?
explainlikeimfive
https://www.reddit.com/r/explainlikeimfive/comments/aigs1m/eli5_why_do_ethics_outweigh_the_benefits_when_it/
{ "a_id": [ "eenlfxn", "eenmtkt", "eenp9r2", "eenvqiy", "eenw2je", "eenwuaw", "eeny1v6", "eeny6dz" ], "score": [ 18, 11, 2, 3, 2, 2, 34, 2 ], "text": [ "As far as I know, the issue people has is that the technology hasn't been tested enough t...
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[ [], [], [], [], [], [], [], [] ]
3sb2t9
Why is the formula for acceleration a=2d/t^2 ? Why not a=d/t^2 ?
In my physics class today my teacher said this was the formula, but why is that?
askscience
https://www.reddit.com/r/askscience/comments/3sb2t9/why_is_the_formula_for_acceleration_a2dt2_why_not/
{ "a_id": [ "cwvo9jg", "cwvryt4" ], "score": [ 18, 2 ], "text": [ "Re-arrange it first: The distance travelled from constant acceleration is 1/2 at^2 , so your question is the same as asking why there is a 1/2 there, why is it just not at^2 .\n\nThe distance traveled during constant accele...
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[ [], [] ]
2hkypx
how does a hsa (health savings account) work and compare to traditional insurance?
The other answers weren't great and are possibly outdated.
explainlikeimfive
http://www.reddit.com/r/explainlikeimfive/comments/2hkypx/eli5_how_does_a_hsa_health_savings_account_work/
{ "a_id": [ "cktmjdp", "cktn7nl", "cktnidh" ], "score": [ 4, 3, 2 ], "text": [ "HSA is a bank account. You put your own money in it pre-tax and it can be used for medical expenses. Your employer can also put money in it. \n\nIt's not insurance by itself, but usually a part of a c...
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[ [], [], [] ]
djsr6r
how do we stay asleep despite switching positions at night or even in extreme cases with people sleep walking?
Just curious as I checked my cameras and noticed I switch positions about ten times a night and still wake up feeling refreshed with no knowledge that I was even moving around.
explainlikeimfive
https://www.reddit.com/r/explainlikeimfive/comments/djsr6r/eli5_how_do_we_stay_asleep_despite_switching/
{ "a_id": [ "f47vy0a", "f488nlb" ], "score": [ 11, 6 ], "text": [ "When you're in that state, it's similar to being blackout drunk. You're not in the best shape to create new memories. People who have sleep apnea wake up dozens of times per hour because they stop breathing, but they won'...
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[ [], [] ]
5zu97q
why is censoring tv & radio not a violation of the first amendment?
explainlikeimfive
https://www.reddit.com/r/explainlikeimfive/comments/5zu97q/eli5_why_is_censoring_tv_radio_not_a_violation_of/
{ "a_id": [ "df13wyk", "df14alr", "df14nuy" ], "score": [ 4, 9, 2 ], "text": [ "My understanding is that the freedoms of speech and press are meant so the government cannot punish you for saying something against them. You are allowed to say anything you want in regards to the gove...
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[ [], [], [] ]