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1g94zl
What is the oldest known human structure?
Pretty simple question to my (uneducated) eyes. What is the oldest known building attributed to man?
AskHistorians
http://www.reddit.com/r/AskHistorians/comments/1g94zl/what_is_the_oldest_known_human_structure/
{ "a_id": [ "cahz5ou", "cahzwzf", "cai1rkd" ], "score": [ 6, 12, 4 ], "text": [ "What about [Gobekli Tepe, in Turkey?](_URL_0_) That seems to go back to about 9000 BC, and although it's not a \"building\" per se (as in walls and a roof), it is a structure. I don't know if anythin...
[]
[]
[ [ "http://www.smithsonianmag.com/history-archaeology/gobekli-tepe.html" ], [ "http://donsmaps.com/clickphotos/mezhdig.jpg", "http://archaeology.about.com/od/mterms/g/mezhirich.htm", "http://donsmaps.com/clickphotos/mezhrecon.gif" ], [ "http://books.google.co.uk/books?id=A0llBlzF6UgC&...
2thad7
how can we use telescopes to see into the far reaches of space, generating massive resolution images, yet we have to send a spacecraft like dawn to see a white spot on ceres?
explainlikeimfive
http://www.reddit.com/r/explainlikeimfive/comments/2thad7/eli5_how_can_we_use_telescopes_to_see_into_the/
{ "a_id": [ "cnz1s4d", "cnz1srw" ], "score": [ 6, 2 ], "text": [ "The things that we can see far away are **very** big and **very** bright.\n\nYou can easily see a billion burning candles arranged on a hilltop miles away in a pitch-black night (seeing another galaxy filled with billions of...
[]
[]
[ [], [ "http://en.wikipedia.org/wiki/Pillars_of_Creation" ] ]
48fedx
Is it possible to observe the process of a star becoming a black hole?
If so, how much of the process? What would it look like to an observer?
askscience
https://www.reddit.com/r/askscience/comments/48fedx/is_it_possible_to_observe_the_process_of_a_star/
{ "a_id": [ "d0kmk3s" ], "score": [ 2 ], "text": [ "You're most likely to see a regular supernova and that's it. Black holes are not visible so without any special equipment you wouldn't even know it's there when it forms only it's interactions to other objects can be detected." ] }
[]
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[ [] ]
2280u7
what do we know about what goes on inside of other planets in our solar system?
explainlikeimfive
http://www.reddit.com/r/explainlikeimfive/comments/2280u7/eli5_what_do_we_know_about_what_goes_on_inside_of/
{ "a_id": [ "cgk9u0w" ], "score": [ 2 ], "text": [ "Not a whole lot of direct study. We can make some measurements - for example, we know their mass and size, so we can calculate their density, which tells us something about what they're made of. Saturn, for example, is very light - less dense tha...
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[ [] ]
1psljm
- where do "royals" obtain their original claim of "royalty" from?
If I declared to everyone that I was God's chosen representative on earth here to rule over everyone, they would lock me in a cage. Why do we treat these people differently?
explainlikeimfive
http://www.reddit.com/r/explainlikeimfive/comments/1psljm/eli5_where_do_royals_obtain_their_original_claim/
{ "a_id": [ "cd5kseu", "cd5lmzo", "cd5lust", "cd5onxp", "cd5qmj1", "cd5rp31", "cd5sas3", "cd5uwz3" ], "score": [ 6, 75, 14, 7, 2, 2, 2, 4 ], "text": [ "Well before the Enlightenment, everyone just agreed on whatever the Church told them.\n\nT...
[]
[]
[ [], [], [], [], [], [], [], [] ]
f437r8
How does the monarch butterfly change its lifespan between generations?
Heard today that while migrating some generations can survive up to almost a year
askscience
https://www.reddit.com/r/askscience/comments/f437r8/how_does_the_monarch_butterfly_change_its/
{ "a_id": [ "fhx9k02" ], "score": [ 2 ], "text": [ "Several things to consider here :\n\n* First of all, the genetic information doesn't say \"that individual will live this long\", it's more like the lifespan depends on many other genetic traits. That means it's not genetic information changing f...
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[ [] ]
6ru00i
The "germ theory of disease" Wikipedia page suggests that germ theory had many antecedents (people talking about "pestifera semina") going back to antiquity. Why was miasma theory popular as of the 19th century?
The [Wikipedia page](_URL_0_) suggests that early mentions of specific "seeds" spreading illness, go back to Thucydides' description of a plague in Athens. Many other examples are cited, which demonstrate some kind of hypothesis that some kind of illness-causing organism is propagating itself through people's bodies an...
AskHistorians
https://www.reddit.com/r/AskHistorians/comments/6ru00i/the_germ_theory_of_disease_wikipedia_page/
{ "a_id": [ "dldjfcx" ], "score": [ 11 ], "text": [ "I've been meaning to write an answer to your question since you posted it, but I didn't get around to actually writing it. Well, I hope that you're still waiting for an answer. \n\nI have a few problems with the history-sections of that Wikipedi...
[]
[ "https://en.wikipedia.org/wiki/Germ_theory_of_disease" ]
[ [] ]
mgkk7
What prevents the intestines from tangling themselves like my headphone cords?
Really, I've always wondered this.
askscience
http://www.reddit.com/r/askscience/comments/mgkk7/what_prevents_the_intestines_from_tangling/
{ "a_id": [ "c30r5we", "c30rank", "c30rjvb", "c30r5we", "c30rank", "c30rjvb" ], "score": [ 3, 10, 23, 3, 10, 23 ], "text": [ "They are held in place by connective tissue. It doesn't give them much room to move around.", "They can get tangled, and it is a...
[]
[]
[ [], [], [], [], [], [] ]
k1hsr
antitrust lawsuits
This thought was sparked by the US Govt. filing an antitrust lawsuit against the AT & T and T-Mobile merger.
explainlikeimfive
http://www.reddit.com/r/explainlikeimfive/comments/k1hsr/eli5_antitrust_lawsuits/
{ "a_id": [ "c2gtdgg", "c2gtdgg" ], "score": [ 2, 2 ], "text": [ "Let's say you have two companies selling apple. Now both companies will sell apples at a good price, let's say that price is $1 an apple. If ether company was to raise their price then they'd sell less apple cause who would ...
[]
[]
[ [], [] ]
kfd21
why can't we recreate dinosaurs just like in jurassic park?
explainlikeimfive
http://www.reddit.com/r/explainlikeimfive/comments/kfd21/eli5_why_cant_we_recreate_dinosaurs_just_like_in/
{ "a_id": [ "c2jtdmr", "c2jtgpj", "c2jtu3v", "c2jtyr1", "c2jv68g", "c2jtdmr", "c2jtgpj", "c2jtu3v", "c2jtyr1", "c2jv68g" ], "score": [ 59, 5, 12, 10, 3, 59, 5, 12, 10, 3 ], "text": [ "To create clones you need to take the nucl...
[]
[]
[ [], [], [ "http://www.youtube.com/watch?v=0QVXdEOiCw8" ], [], [], [], [], [ "http://www.youtube.com/watch?v=0QVXdEOiCw8" ], [], [] ]
33x7do
sd cards
multipart question (poor formatting because I'm mobile) 1. SD cards, a very small piece of plastic with a few grams of metal, is extremely expensive. whats the raw cost of an SD card (the price of the plastic + metal), ignoring everything else -surely the price is extremely small, and manufacturing these on a large sc...
explainlikeimfive
http://www.reddit.com/r/explainlikeimfive/comments/33x7do/eli5_sd_cards/
{ "a_id": [ "cqp8bde" ], "score": [ 2 ], "text": [ "You are right the plastics bits and the copper contacts that make up moth of the SD card that you can see have a negligible price. They are not worth much.\n\nThe actual flash memory itself inside the card is what makes up most of the price. It c...
[]
[]
[ [ "http://i.imgur.com/j4C4iST.jpg" ] ]
1oaldb
if a bank goes out of business and i happen to have a mortgage with said bank, what would happen?
explainlikeimfive
http://www.reddit.com/r/explainlikeimfive/comments/1oaldb/eli5_if_a_bank_goes_out_of_business_and_i_happen/
{ "a_id": [ "ccq91f3", "ccq9vy4" ], "score": [ 5, 2 ], "text": [ "They would sell your debt to someone else as a way of paying off their debts, and now you owe your mortgage to some other entity.", "Essentially, the debt they have on you is an asset, in much the same was a copy machine...
[]
[]
[ [], [] ]
96x8vk
Are planets exclusively formed after stars from the remaining material, or are there other natural ways we've observed/theorized planet(s) forming?
askscience
https://www.reddit.com/r/askscience/comments/96x8vk/are_planets_exclusively_formed_after_stars_from/
{ "a_id": [ "e45c3sa" ], "score": [ 3 ], "text": [ "Technically speaking a planet is defined as an object orbiting a star, though this gets a bit problematic when considering rogue planets that have been ejected from their stars.\n\nThe same process that leads to star formation--collapse of cloud ...
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[ [] ]
qw1bu
Resources for Medieval Church/Choir Music
I was wondering if any medieval scholars could point me to resources where I could get my hands on authentic medieval choir music for a project. I'm thinking of the stereotypical music you hear in movies and video games which immediately connote the medieval. Thanks!
AskHistorians
http://www.reddit.com/r/AskHistorians/comments/qw1bu/resources_for_medieval_churchchoir_music/
{ "a_id": [ "c40xmhy", "c40yxv2" ], "score": [ 3, 3 ], "text": [ "The answer sort of depends on exactly what you're looking for. Most of the music used in video games and movies is composed recently, it's not authentic medieval music. They get the same sound by using a lot of open fourth...
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[]
[ [ "http://www.youtube.com/watch?v=Xt3H2uGxFLI", "http://www.youtube.com/watch?v=RPQjqZm6q0Q", "http://www.youtube.com/watch?v=bpgaEFmdFcM&feature=related", "http://imslp.org/wiki/" ], [ "http://www.youtube.com/watch?v=gtkmnhnHWhw" ] ]
8tnr78
What did the people of the Spanish peninsula look like before the Moors arrived?
AskHistorians
https://www.reddit.com/r/AskHistorians/comments/8tnr78/what_did_the_people_of_the_spanish_peninsula_look/
{ "a_id": [ "e19p4ph" ], "score": [ 9 ], "text": [ "Hi there! So if we're talking about what they \"looked like\" I'm assuming you meant in terms of their actual physical appearance. The short version is that there was an array of people and cultures in Iberia and their appearances varied accordin...
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[ [] ]
1imlbm
the difference between poisonous and toxic things
explainlikeimfive
http://www.reddit.com/r/explainlikeimfive/comments/1imlbm/eli5_the_difference_between_poisonous_and_toxic/
{ "a_id": [ "cb5xi1l" ], "score": [ 3 ], "text": [ "The term poison refers to any substance that is harmful to your body if consumed. Toxin is a specific branch of poison, defining naturally created poisons. For example, many household cleaning substances are poisonous, but are artificially made...
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[]
[ [ "http://www.omg-facts.com/Science/Poison-Toxin-And-Venom-Are-Three-Complet/52899" ] ]
30n57t
If there was no oxygen and paper was heated to a super high temperature, would it melt not burn?
For example if there was a piece of paper in a sealed box (able to withstand high temperatures) with no oxygen (maybe filled with an inert gas like neon?) what would happen when it's heated enough to break the C-H bonds and have nothing to react with? would it just create pure C and H2 gas?
askscience
http://www.reddit.com/r/askscience/comments/30n57t/if_there_was_no_oxygen_and_paper_was_heated_to_a/
{ "a_id": [ "cpuire7", "cpupm0a" ], "score": [ 3, 3 ], "text": [ "Yes. There couldn't be any chemical reactions, and if you reach the necessary temperature it will break down into its parts. That would happen around 250° celsius temperature. You would be left with charcoal and hydrogen gas...
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[]
[ [], [ "http://en.wikipedia.org/wiki/Pyrolysis" ] ]
1iw189
If I continuously shot charged particles into a black hole, what would happen over time with the buildup of charge?
Let's say I have an unlimited source of electrons. If I continuously let them stream into a black hole, in what ways do the electrons influence their surroundings? Could an observer ever feel an electrical repulsion or attraction from a charged black hole? Also, given enough buildup, could the charge rip the black hole...
askscience
http://www.reddit.com/r/askscience/comments/1iw189/if_i_continuously_shot_charged_particles_into_a/
{ "a_id": [ "cb8nz67", "cb8o0yf" ], "score": [ 4, 70 ], "text": [ "From the [no-hair theorem](_URL_0_), the only things that external observers can measure from a black hole are its mass, charge, and angular momentum. \n\nSo yes, the black hole will become more and more negatively charged...
[]
[]
[ [ "http://en.wikipedia.org/wiki/No-hair_theorem" ], [] ]
3xa2bb
how did futurama win 6 emmys but got canceled twice?
explainlikeimfive
https://www.reddit.com/r/explainlikeimfive/comments/3xa2bb/eli5_how_did_futurama_win_6_emmys_but_got/
{ "a_id": [ "cy2tyq0", "cy2ux2e", "cy2vdiy", "cy31pw1", "cy31q8z", "cy31s2e", "cy31s4q", "cy31ud8", "cy31uyv", "cy325cr", "cy32p6r", "cy32x09", "cy33b3l", "cy33e7j", "cy33m4z", "cy344g3", "cy349ay", "cy349pl", "cy354oq", "cy35j0w", "c...
[]
[]
[ [], [], [], [], [], [], [], [], [], [], [], [], [ "http://theinfosphere.org/Cancellation_of_Futurama" ], [], [], [], [], [], [ "https://www.youtube.com/watch?v=rD9i_9Gf2nY&t=48s" ], [], [], [], [ "https://www.youtube.com/watch?v=HmGGVARy1OQ" ], [],...
2yimbh
why is the letter the 47 republican senators sent to iran today such a big deal?
explainlikeimfive
http://www.reddit.com/r/explainlikeimfive/comments/2yimbh/eli5_why_is_the_letter_the_47_republican_senators/
{ "a_id": [ "cp9val5", "cp9vdr6", "cp9vfdr", "cp9vplv" ], "score": [ 3, 6, 14, 3 ], "text": [ "Well, for one there is the [Logan Act](_URL_0_)\nAnd then again, aren't we all getting a little tired of the Republican's shit?", "Negotiating with foreign powers is the job o...
[]
[]
[ [ "http://en.wikipedia.org/wiki/Logan_Act" ], [], [], [] ]
fvx8n5
how do companies like gm and apple quickly pivot to making new products like masks and ventilators?
explainlikeimfive
https://www.reddit.com/r/explainlikeimfive/comments/fvx8n5/eli5_how_do_companies_like_gm_and_apple_quickly/
{ "a_id": [ "fmkz1q2" ], "score": [ 2 ], "text": [ "I think it’s not so much that they switch to manufacturing masks and ventilators, they just have them already and are donating them. At least for apple and other big tech companies, their factories are big clean rooms, so they have plenty of mask...
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[ [] ]
5d6nuu
what would happen in the usa if someone tore a ligament (such as acl) and didn't have health insurance?
explainlikeimfive
https://www.reddit.com/r/explainlikeimfive/comments/5d6nuu/eli5what_would_happen_in_the_usa_if_someone_tore/
{ "a_id": [ "da26lbg" ], "score": [ 4 ], "text": [ "You would have to pay out of pocket. Usually if you don't have insurance, you may be able to negotiate the costs with hospital to lower the amount due. \n\nGenerally, hospitals will charge more for procedures and hospital stays if a patient's ins...
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[ [] ]
3iuk49
why do people who have sex in movies/shows smoke after it?
explainlikeimfive
https://www.reddit.com/r/explainlikeimfive/comments/3iuk49/eli5_why_do_people_who_have_sex_in_moviesshows/
{ "a_id": [ "cujqm2t" ], "score": [ 10 ], "text": [ "It's TV trope, but based on reality. Back when I was a smoker the most enjoyable cigarettes were after sex, after a good meal, and when drinking." ] }
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[ [] ]
1q3yb9
What is happening in a black hole? Do we have fusion of heavy elements? Could they eventually super nova?
askscience
http://www.reddit.com/r/askscience/comments/1q3yb9/what_is_happening_in_a_black_hole_do_we_have/
{ "a_id": [ "cd94861" ], "score": [ 6 ], "text": [ "To answer your last question first: no, a black hole cannot supernova. Once matter is inside its event horizon, it's in there for good. It appears, by using quantum physics to study black hole event horizons, that they can emit radiation (called ...
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[ [] ]
1st22j
please explain fetal alcohol syndrome (many more-specific questions herein)
I am a new teacher in the far north (Alaska), in a village where FAS is supposedly pretty commonplace. I understand some basics of FAS (the mother drinks during pregnancy, child is born with cognitive disabilities), but there's a lot that I don't know, or know how best to deal with. (As much as 35% of the kids at our s...
explainlikeimfive
http://www.reddit.com/r/explainlikeimfive/comments/1st22j/eli5_please_explain_fetal_alcohol_syndrome_many/
{ "a_id": [ "ch7k84i", "ce0yng2", "ce10yq4", "ce13icp" ], "score": [ 3, 3, 2, 2 ], "text": [ "Wow. Four months ago. Still, I think I can add a bit to this, and hope you will see it.\nMy mother has grown up with FAS. I don't expect anyone in her family would admit it, but sh...
[]
[]
[ [], [ "http://www.ncbi.nlm.nih.gov/pubmedhealth/PMH0001909/", "http://emedicine.medscape.com/article/974016-overview", "http://www.cdc.gov/NCBDDD/fasd/facts.html", "http://www.cdc.gov/ncbddd/fasd/diagnosis.html" ], [], [] ]
1u8mrr
what is nsa doing with my information?
explainlikeimfive
http://www.reddit.com/r/explainlikeimfive/comments/1u8mrr/eli5_what_is_nsa_doing_with_my_information/
{ "a_id": [ "cefk1tq", "cefkxdf" ], "score": [ 3, 15 ], "text": [ "It's collecting metadata (data about a conversation, not the conversation itself) into a big database so that, if the need ever arises, they can analyze that data to see who you might have conversed/connected to, or if you ...
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[]
[ [], [] ]
9ihvkv
How prevalent was looting by US troops during WWII?
In Band of Brothers there is a scene where a officer is putting looted goods into a shipping box to be sent back to the US. How common was this sort of thing? What were the legalities of people taking property they 'found' and sending it home? How often did it happen? What were the policies towards this behavior?
AskHistorians
https://www.reddit.com/r/AskHistorians/comments/9ihvkv/how_prevalent_was_looting_by_us_troops_during_wwii/
{ "a_id": [ "e6jrbpo", "e6jzngz" ], "score": [ 2019, 105 ], "text": [ "Looting by the US military during World War II fell into several categories, which can broadly be grouped as the 'legal' and 'illegal', even if lines might have blurred at times. First and foremost it can be said that t...
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[]
[ [], [ "https://www.trouw.nl", "https://www.trouw.nl/home/een-zwarte-pagina-in-de-bevrijding-van-nederland~ad14f795/" ] ]
4e8r2j
how and why we feel the emotion, "boredom" whenever we aren't doing anything?
explainlikeimfive
https://www.reddit.com/r/explainlikeimfive/comments/4e8r2j/eli5_how_and_why_we_feel_the_emotion_boredom/
{ "a_id": [ "d1y1kiz", "d1y1r6l", "d1y1zl6" ], "score": [ 27, 5, 2 ], "text": [ "Well I dunno about you but if I'm not on ADHD meds I feel bored damn near constantly. Like painful, unbearable boredom.\n\nSo... in light of that, I'm going to go out on a limb and say when you're sitt...
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[]
[ [], [], [] ]
242bxr
What is the value of Monte Carlo method? Doesn't it just return the expected set of results and variance?
What is the value of Monte Carlo method? Using a simple example of a coin toss: I can expect 1/2 chance of landing on either side, with a Gaussian distribution. Running a Monte Carlo simulation with say, 10^9 coin tosses won't get me valuable results. It'll return my initial setup. Why is Monte Carlo exempt from "gar...
askscience
http://www.reddit.com/r/askscience/comments/242bxr/what_is_the_value_of_monte_carlo_method_doesnt_it/
{ "a_id": [ "ch2x13o", "ch2x7ho", "ch2xhve", "ch2z2pi", "ch30oke" ], "score": [ 5, 16, 4, 7, 3 ], "text": [ "It's useful for simulating more complex scenarios. For example, I've been working on a muon telescope recently. The muon flux is a fairly well known quantity...
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[]
[ [], [], [], [], [] ]
c1b99f
the differences and processes of rom and ram
explainlikeimfive
https://www.reddit.com/r/explainlikeimfive/comments/c1b99f/eli5_the_differences_and_processes_of_rom_and_ram/
{ "a_id": [ "erc13hs" ], "score": [ 2 ], "text": [ "Rom - read only memory. The chip is programmed once, usually by using a writing voltage that is high enough to “burn” the bits in. \n\nRam - random access memory. You can read and write to it. Writing doesn’t burn bits in, each bit is just basic...
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[ [] ]
9pcvff
why do car commercial disclaimers at the end always play so fast that you can't even understand what they're saying?
[deleted]
explainlikeimfive
https://www.reddit.com/r/explainlikeimfive/comments/9pcvff/eli5_why_do_car_commercial_disclaimers_at_the_end/
{ "a_id": [ "e80r0x2" ], "score": [ 12 ], "text": [ "Because the company is legally obliged to include the message but doesn't want to spend ad time that they pay for on legal requirement that doesn't help woth the sales. So they keep it as fast and short as possible. " ] }
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[ [] ]
2iu2y5
Historical use of a "gun-blade"?
My uncle used to have a pair of these short swords, whose handle was a grip and trigger with the barrel running parallel to the blade. They looked old and he didn't care if they were authentic or not due to the aesthetic, however I'm wondering, have these ever been a thing? They looked to me as if they were late 18th e...
AskHistorians
http://www.reddit.com/r/AskHistorians/comments/2iu2y5/historical_use_of_a_gunblade/
{ "a_id": [ "cl5kt56", "cl5l16w", "cl5nd2o", "cl5w0n8" ], "score": [ 2, 4, 9, 2 ], "text": [ "Can you post a pic, or find a pic of something similar to refer to?", "[it's been asked before](_URL_0_) but wasn't answered in a lot of detail, you might find more info with t...
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[]
[ [], [ "https://www.reddit.com/r/AskHistorians/comments/1wd7fx/were_gunblades_ever_a_thing/" ], [ "https://i.imgur.com/OFRa1kT.jpg", "http://firearmshistory.blogspot.com/2010/12/combined-firearms-daggers.html" ], [] ]
oqfjm
Why are some pharmaceuticals bounded to an hydrochloride and some to an hydrobromide?
Dextromethorphan is typically solubilized with HBr while morphine is often made into a salt with HCl. Why not always HCl? Is there such a difference between the solubilities?
askscience
http://www.reddit.com/r/askscience/comments/oqfjm/why_are_some_pharmaceuticals_bounded_to_an/
{ "a_id": [ "c3j7p9h" ], "score": [ 3 ], "text": [ "There is a difference in how well the crystals form. Larger ions like larger counter-ions, typically, to make stable crystals. When making the drug you want stable crystals to recover the most product cleanly at the end of the manufacturing proce...
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[ [] ]
5i9bgn
During the Medieval period, how often were nobility/knights/etc captured in battle?
AskHistorians
https://www.reddit.com/r/AskHistorians/comments/5i9bgn/during_the_medieval_period_how_often_were/
{ "a_id": [ "db6p93k" ], "score": [ 2 ], "text": [ "Not op, follow.up questions:\n\nHow are the nobles/knights/etc generally treated when they were captured?" ] }
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[ [] ]
48ratj
radio waves allegedly detected coming from another galaxy. how long ago are they likely to be from?
So I already looked up this part: radio waves travel at the speed of light. If the waves are traveling at light's speed, does that mean that they are from a time that is how ever many light years away they are (divide by the speed of light, already in the formula)? So does this mean that if they are coming from a civi...
explainlikeimfive
https://www.reddit.com/r/explainlikeimfive/comments/48ratj/eli5radio_waves_allegedly_detected_coming_from/
{ "a_id": [ "d0lupa9" ], "score": [ 5 ], "text": [ "Radio astronomer checking in:\n\nYes, radio waves travel at the speed of light (radio waves ARE light, just lower energy than visible light), so the travel time is equal to the distance in light-years. Radio waves from a galaxy 10 million lightye...
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[ [] ]
1244rk
marginal cost
I have the definition as: increase or decrease in costs as a result of one more or one less unit of output. But how exactly does this work?
explainlikeimfive
http://www.reddit.com/r/explainlikeimfive/comments/1244rk/eli5_marginal_cost/
{ "a_id": [ "c6rzoib" ], "score": [ 3 ], "text": [ "There are some business costs that don't depend on how productive you are. Even if you produce absolutely nothing this year, you still have to pay for building space and air conditioning and stuff.\n\nBut there are some costs that *do* depend on ...
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1ngmb8
How do we know for certain that we have found every single naturally occurring element?
Just wondering, is it possible there could be undiscovered elements on other planets or in the core of the Earth perhaps?
askscience
http://www.reddit.com/r/askscience/comments/1ngmb8/how_do_we_know_for_certain_that_we_have_found/
{ "a_id": [ "ccifn0u", "ccigfet" ], "score": [ 4, 16 ], "text": [ "When an element is called natural, this only means that it was identified in nature rather than created in a laboratory. However, there is nothing special about natural elements, it's entirely conceivable that there may be ...
[]
[]
[ [], [ "http://en.wikipedia.org/wiki/Island_of_stability" ] ]
1bu89i
Did the big bang occur in all directions? I often hear that we can only see 13.?? billion light years before we can't see anymore, but isn't there technically another 13.?? billion light years worth of material beyond the initial bang, just in the other direction?
Sorry if the question doesn't make sense.. I worded it the best I could. Basically, am I incorrect in thinking the big bang would have occurred in the shape of a balloon rather than a wall? If the shape is more balloon-like, why can we not see past the center?
askscience
http://www.reddit.com/r/askscience/comments/1bu89i/did_the_big_bang_occur_in_all_directions_i_often/
{ "a_id": [ "c9a5dci", "c9a5l75", "c9a5lf3", "c9a68yg", "c9ajoy7" ], "score": [ 12, 5, 2, 3, 3 ], "text": [ "The misunderstanding here comes from your idea of the \"center\" if the universe.\n\nThere isn't one. Every point in the universe appears to be moving away f...
[]
[]
[ [], [ "https://www.youtube.com/watch?v=5NU2t5zlxQQ&feature=youtube_gdata_player" ], [], [ "http://en.wikipedia.org/wiki/Cosmic_microwave_background_radiation" ], [ "http://www.physicsforums.com/archive/index.php/t-506987.html" ] ]
1if8ky
What is the history of the Smith-Mundt act? Why did congress pass a law banning domestic audiences from hearing material intended for foreign audiences?
AskHistorians
http://www.reddit.com/r/AskHistorians/comments/1if8ky/what_is_the_history_of_the_smithmundt_act_why_did/
{ "a_id": [ "cb3wqcr", "cb45j2p" ], "score": [ 9, 3 ], "text": [ "If you are at an institution with free access to legal databases, you can get greater depth from the legislative records cited below, but here is what I could dig up from free sources:\n\nThe initial 1948 law provides that:\...
[]
[]
[ [ "http://scholar.google.com/scholar_case?case=10884445047014370387", "http://scholar.google.com/scholar_case?case=14052676309006831774" ], [] ]
eji1hh
What is the status of Fredrick Jackson Turner's Frontier Thesis among historians today? Is it still used as an explanation of broader aspects of US historical trends, or closer to something that illuminates how Americans in the early 20th century thought about their own past?
AskHistorians
https://www.reddit.com/r/AskHistorians/comments/eji1hh/what_is_the_status_of_fredrick_jackson_turners/
{ "a_id": [ "fcy7464" ], "score": [ 13 ], "text": [ "After ninety-five years (or so) of two camps - the Turnerians and the anti-Turnerians - bashing one another, there was something of a collective sigh of relief when the controversy around the Turner Thesis was set aside. Even though it was large...
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[]
[ [] ]
934hfj
What was the casualty rate for battles between hoplites in ancient Greece?
I would assume that the answer would vary depending on when and where the fight took place, and who was participating. But in general how bloody an affair was war in the Hellenic world. My limited understanding on the matter is that battles were largerly a test of strength: with both sides lining up, singing war song...
AskHistorians
https://www.reddit.com/r/AskHistorians/comments/934hfj/what_was_the_casualty_rate_for_battles_between/
{ "a_id": [ "e3asven" ], "score": [ 44 ], "text": [ "Back in the 80s, Peter Krentz gathered all known casualty figures from Classical Greek sources in order to establish a rough average.^1 He concluded that in battles of Greek against Greek, the winner suffered about 5% casualties, the loser about...
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[ [ "https://www.reddit.com/r/AskHistorians/comments/48pumt/did_the_people_in_the_front_lines_of_ancient/d0ly1na/" ] ]
6sz4ln
- why does water bead up where i wrote on a dirty car, and why does it take so long to disappear?
Today, I wrote "Hail Satan" on my mother's car that is covered in dust. She promptly sprayed it with the hose to clean it off, but nervously joked that it really was Satan immediately after the water beaded up and spelled it out again. She tried scrubbing it and spraying it, but it kept coming back (after about 4 cycle...
explainlikeimfive
https://www.reddit.com/r/explainlikeimfive/comments/6sz4ln/eli5_why_does_water_bead_up_where_i_wrote_on_a/
{ "a_id": [ "dlgoi5e", "dlgoleu" ], "score": [ 2, 2 ], "text": [ "Oil from your skin and the fact that dust is abrasive when you write with your finger on dust it scratches the paint/ clear coat.", "This is due to a phenomenon called surface tension. The most economical position for ma...
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[ [], [] ]
7mglm5
why does produce from farmer’s markets cost more than organic produce from a grocery store if the middlemen are removed?
explainlikeimfive
https://www.reddit.com/r/explainlikeimfive/comments/7mglm5/eli5_why_does_produce_from_farmers_markets_cost/
{ "a_id": [ "drtqxb6", "drtrlfn", "drtscs3" ], "score": [ 9, 8, 2 ], "text": [ "In countries like the USA (where labor is costly), farmer's market stands are not cost-efficient. You have a whole person or two, putting in 4-6 hours of work, just to sell a couple of hundred dollars w...
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[]
[ [], [ "http://www.tampabay.com/projects/2016/food/farm-to-fable/farmers-markets/", "https://blogs.scientificamerican.com/science-sushi/httpblogsscientificamericancomscience-sushi20110718mythbusting-101-organic-farming-conventional-agriculture/" ], [] ]
1apyj0
As previously stated, Soldiers from ancient times were lean and fit, what were gladiators like?
As i understand ancient armies were lean and lightly muscled mainly to do with the fact that they were continuously on the march or making fortifications. What i want to know is what were the gladiators like? People trained for shows of short and brutal combat? were they heavily muscled and brutally strong or were they...
AskHistorians
http://www.reddit.com/r/AskHistorians/comments/1apyj0/as_previously_stated_soldiers_from_ancient_times/
{ "a_id": [ "c8zo0tw", "c8zos27" ], "score": [ 3, 2 ], "text": [ "I'm working on finding the source at the moment but, as far as I remember, gladiators were actually kind of flabby.\n\n[Edit]\n\nThe Archaeological Institute of America has an article [here](_URL_0_) that covers the research...
[]
[]
[ [ "http://archive.archaeology.org/0811/abstracts/gladiator.html" ], [ "http://www.reddit.com/r/AskHistorians/comments/12uazu/in_terms_of_physique_would_real_gladiators_have/", "http://www.reddit.com/r/AskHistorians/comments/179vp0/would_a_gladiator_beat_a_trained_soldier_in_combat/", "http://www...
9l08g1
How did early humans switch from hunter-gatherer to agriculture?
I can't imagine that they simply decided one day that "fuck all this running around, we're just going to eat what's growing around here". They must have needed some time to develop agricultural practices, identify and develop worthwhile crops. But all that would have required them to regularly revisit the same spots t...
askscience
https://www.reddit.com/r/askscience/comments/9l08g1/how_did_early_humans_switch_from_huntergatherer/
{ "a_id": [ "e74xefn", "e752ppc", "e7599ca" ], "score": [ 3, 3, 2 ], "text": [ "I actually studied this quite a bit in undergrad. The first thing to remember is that it varies by region. There are many independent origins of agriculture around the world and not all of them happen...
[]
[]
[ [], [], [] ]
58yqjf
whаt nutrіеnts dоеs саrtіlаgе nееd?
For repairing itself
explainlikeimfive
https://www.reddit.com/r/explainlikeimfive/comments/58yqjf/eli5_whаt_nutrіеnts_dоеs_саrtіlаgе_nееd/
{ "a_id": [ "d94guuk", "d94m55j" ], "score": [ 5, 2 ], "text": [ "The non-essential amino acids proline and glycine are building blocks for cartilage. Your body can synthesize them, but dietary intake from gelatinous meats will likely aid in your body's ability to heal. A study was done ...
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[ [], [] ]
2pzf0t
if orangutans share approximately 97% dna with humans, why do they look so different than humans?
explainlikeimfive
http://www.reddit.com/r/explainlikeimfive/comments/2pzf0t/eli5_if_orangutans_share_approximately_97_dna/
{ "a_id": [ "cn1di0y", "cn1dnu6" ], "score": [ 4, 2 ], "text": [ "The other 3%.\n\nAnd really, they don't look all that different from us. Sure, if you had 100 humans and one orangutan in a room, the orangutan would stand out; but if you had 1000 animals of all types, the orangutan and the...
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[]
[ [], [] ]
z09e2
How different was the culture and language of the Scottish Highlands from that of the Lowlands?
I remember reading that most lowland Scots didn't even speak Gaelic, and that many of the Aristocracy were of Anglo-Norman stock. Is this true?
AskHistorians
http://www.reddit.com/r/AskHistorians/comments/z09e2/how_different_was_the_culture_and_language_of_the/
{ "a_id": [ "c60epxu", "c60fbz5" ], "score": [ 4, 2 ], "text": [ "When?\n\nScotti is the Latin name for the Irish, (or, alternatively, northern Irish) who frequently raided Britain. (Gael comes from Welsh Gwydel which is raider, iirc, akin to Viking meaning pirate or something along those ...
[]
[]
[ [], [] ]
662wro
$ vs. ¢
explainlikeimfive
https://www.reddit.com/r/explainlikeimfive/comments/662wro/eli5_vs/
{ "a_id": [ "dgf4yac" ], "score": [ 2 ], "text": [ "To avoid ambiguity, although it isn't always the case that the main currency symbol goes in front. In many languages, it goes at the end regardless.\n\nHaving it in front is useful for two purposes, however. Firstly, it helps prevent people fro...
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[]
[ [] ]
8ptq1a
[Astronomy] Is there a correlation between galaxy age and the amount of dark matter in it?
Have we figured out any way of predicting how much dark matter is in a galaxy, for example, the age of the galaxy, or how much visible matter there is in it?
askscience
https://www.reddit.com/r/askscience/comments/8ptq1a/astronomy_is_there_a_correlation_between_galaxy/
{ "a_id": [ "e0gmlu1" ], "score": [ 2 ], "text": [ "the part of the galaxy that contains dark matter is called the \"dark matter halo\" and contains the majority of the mass in a standard galaxy. it is really hard to accurately weigh a galaxy and determine the amount of dark matter in it, although...
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[]
[ [ "https://www.nasa.gov/feature/goddard/2018/dark-matter-goes-missing-in-oddball-galaxy", "https://www.space.com/33850-weird-galaxy-is-mostly-dark-matter.html" ] ]
1094s1
what should i be looking for when i'm reading nutrition facts?
What's considered healthy? Which fats do I not want? How much is too much?
explainlikeimfive
http://www.reddit.com/r/explainlikeimfive/comments/1094s1/eli5_what_should_i_be_looking_for_when_im_reading/
{ "a_id": [ "c6bfojz", "c6bfsau", "c6bfvnf", "c6bgp8l", "c6bkfwc" ], "score": [ 34, 11, 2, 29, 4 ], "text": [ "The most important fact you need to know: **Serving size** \nAnd also the \"Number of Servings\"", "The actual nutritional content depends o...
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[]
[ [], [], [], [], [] ]
153ygr
Is there a correlation between exposure to cold weather and getting viral/bacterial infections?
I understand that when it's colder, people are more likely to stay indoors, which allows for better transmission of pathogens. However, does actually being cold facilitate the infection process? PS: my parents insist that the culprit is cold weather whenever I develop symptoms matching a bacterial or viral infection (...
askscience
http://www.reddit.com/r/askscience/comments/153ygr/is_there_a_correlation_between_exposure_to_cold/
{ "a_id": [ "c7j2ru4", "c7j2saa", "c7j2yvm", "c7j3bpf", "c7j9smv" ], "score": [ 3, 2, 2, 5, 2 ], "text": [ "AFAIK, it's purely based on being indoors and easing the spread of germs. If the logic were that it were related to the cold, then equatorial countries would ...
[]
[]
[ [], [], [], [ "http://www.reddit.com/r/askscience/comments/lt953/why_does_being_in_the_cold_cause_you_to_be_sick/", "http://www.reddit.com/r/askscience/comments/jf3tb/can_being_wet_and_cold_for_prolonged_periods_lead/", "http://www.reddit.com/r/askscience/comments/kjx10/does_being_cold_cause_cold/...
b4100l
why/how does the gas released by freshly cut onions clear the nose and sinuses when ill?
Some clarification: In my family when we have a cold or a more severe illness involving a blocked or runny nose or pain in the ear canal, we cut up a big onion, roll it up in a thin linen cloth and hang it around our neck with the use of a safety-pin. The onion needs to be refreshed every 8-12 hours for the effect to ...
explainlikeimfive
https://www.reddit.com/r/explainlikeimfive/comments/b4100l/eli5_whyhow_does_the_gas_released_by_freshly_cut/
{ "a_id": [ "ej4mere" ], "score": [ 2 ], "text": [ "This \"gas\" (actually a volatile liquid) is called syn-propanethial-S-oxide. It is an irritant that affects the mucous membranes and tear glands to secrete a lot of liquid. This liquid washes out any hardened snot that might be stuck to your muc...
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[ [] ]
4o8ck8
Does alpha decay lead to an ion being made as the atom has lost two protons and so now has two more electrons than protons?
I know it forms a new elements but is this element an ion. Thanks
askscience
https://www.reddit.com/r/askscience/comments/4o8ck8/does_alpha_decay_lead_to_an_ion_being_made_as_the/
{ "a_id": [ "d4ajxkf", "d4bg2ku" ], "score": [ 6, 3 ], "text": [ "Yes conservation of charge means that the resulting atom will be in a -2 charge state. Generally this state is not stable and the atom will interact quickly with local chemistry in some way to lose that charge. Some smaller ...
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[ [], [] ]
3yx6c7
Are there any examples of slavery supporters in the American South who changed their mind and rejected slavery (either before or after the Civil War)?
AskHistorians
https://www.reddit.com/r/AskHistorians/comments/3yx6c7/are_there_any_examples_of_slavery_supporters_in/
{ "a_id": [ "cyhds2l" ], "score": [ 2 ], "text": [ "I have no doubt there will be a great deal of examples that people more familiar with american politics then myself can state but one example would be Rebecca Fleton a georgian feminist who is mostly known for being the first female senator (albe...
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[ [] ]
6j4voh
Has a submarine ever sunk another submarine, in any war, ever?
Edit: forgot to ask, what defenses were subs given against other subs? Did subs even encounter other subs often enough for this to be a problem?
AskHistorians
https://www.reddit.com/r/AskHistorians/comments/6j4voh/has_a_submarine_ever_sunk_another_submarine_in/
{ "a_id": [ "djbmrww", "djc4chl" ], "score": [ 47, 2 ], "text": [ "More than a few times. In the Pacific theater, USN submarines sank the Japanese Ro-45 (although this claim is disputed), I-28, I-29, I-73, I-168, and I-183 as well as the *Monsun-Gruppe*'s [U-537](_URL_5_) and [U-183](_URL_...
[]
[]
[ [ "http://www.combinedfleet.com/I-34.htm", "http://uboat.net/allies/merchants/ships/442.html", "http://www.uboat.net/wwi/boats/index.html?boat=7", "http://uboat.net/allies/merchants/warships.html?sort_by=type", "http://www.combinedfleet.com/sensuikan.htm", "http://uboat.net/boats/u537.htm", ...
a6cqs1
If graphene is a single layer of carbon atoms, how would it conduct electricity?
Essentially asking the mechanics of how graphene conducts electricity. Is it possible to make a super durable/malleable wire/“tape” that can conduct electricity for a cheap price?Any research papers I can dive into too?
askscience
https://www.reddit.com/r/askscience/comments/a6cqs1/if_graphene_is_a_single_layer_of_carbon_atoms_how/
{ "a_id": [ "ebu89d8", "ebxi207" ], "score": [ 6, 3 ], "text": [ "It’s graphene’s structure that makes it conducive. A given carbon atom shares sigma-bonds with 3 other carbon atoms in the same layer, and pi-bonds with the adjacent layers. This pi-bond (actually pi-band) enables free elect...
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[ [ "https://www.researchgate.net/publication/303896294_A_Review_on_the_Properties_and_Applications_of_Graphene" ], [] ]
1ir9r3
can anyone recommend me some eli5-like books on finance/money?
I don't really know anything about financial terms like pensions, credit, equity, assets, trusts, etc...
explainlikeimfive
http://www.reddit.com/r/explainlikeimfive/comments/1ir9r3/can_anyone_recommend_me_some_eli5like_books_on/
{ "a_id": [ "cb7ay7r" ], "score": [ 2 ], "text": [ "The dummies books are great, they have them on financing and all of those topics you talked about and they'll walk you through how to do those things. \n\nSource: success in several investments from reading those books" ] }
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[ [] ]
651vuo
If deleted data can be retrieved, why can't we have our things in deleted state and keep much more space on hard drive disks ?
askscience
https://www.reddit.com/r/askscience/comments/651vuo/if_deleted_data_can_be_retrieved_why_cant_we_have/
{ "a_id": [ "dg71e59", "dg747to", "dg79u34", "dg7qbn5" ], "score": [ 7, 32, 7, 16 ], "text": [ "This would not work because there is a limit to the space that exists on a hard drive. Data can only be retrieved from a hard drive before it has been overwritten.\n\nWhat you're...
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[ [], [], [], [] ]
6paa6l
Each 10m underwater adds roughly 1atm in pressure. Does that change with liquids other than water? Would it be different in planets other than Earth?
askscience
https://www.reddit.com/r/askscience/comments/6paa6l/each_10m_underwater_adds_roughly_1atm_in_pressure/
{ "a_id": [ "dkobw47", "dkoe88d" ], "score": [ 7, 2 ], "text": [ "Yes, that is specific to the density of water (d), the strength of gravity on the Earth (g). The pressure is g times d time the height of the column h, so if the density is twice that of water, only 5 meters would be require...
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[ [], [] ]
2eyhce
when i'm on a cell phone, and i can hear the other person crystal clear, but they say the quality is so bad on their end that they can hardly understand me, what's going on?
explainlikeimfive
http://www.reddit.com/r/explainlikeimfive/comments/2eyhce/eli5_when_im_on_a_cell_phone_and_i_can_hear_the/
{ "a_id": [ "ck46nri", "ck46q9u", "ck4af3s", "ck4anae", "ck4bw7a", "ck4c3ir", "ck4cp6b", "ck4d9dq", "ck4db8b", "ck4h611", "ck4ht7n", "ck4k57m", "ck4k5ec", "ck4kecn", "ck4ki3g", "ck4kj7z", "ck4kk99", "ck4kkar", "ck4kn7u", "ck4l0n5", "c...
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[ [], [], [], [], [], [], [], [], [], [], [], [], [], [], [], [], [], [], [], [], [], [], [], [], [], [], [], [], [], [], [], [] ]
6rynyk
Did the UK ever come close to any serious food shortages in WWII?
From what I know, meat and its by-products wete the heaviest rationed food items, but was rationing as necessary as they made it seem during the war? And did things improve as the war went on?
AskHistorians
https://www.reddit.com/r/AskHistorians/comments/6rynyk/did_the_uk_ever_come_close_to_any_serious_food/
{ "a_id": [ "dl97g2s", "dl9a67o" ], "score": [ 4, 2 ], "text": [ "Not really.\n\nThe Germans had a target of sinking ~300,000 tons of shipping each month in order to starve Britain, and overwhelm British/Allied ship production.\n\nIn the first 27 months of the war, Germany only hit that ta...
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[ [], [] ]
20keib
what does the chipset on a motherboard do and how does it work?
explainlikeimfive
http://www.reddit.com/r/explainlikeimfive/comments/20keib/eli5_what_does_the_chipset_on_a_motherboard_do/
{ "a_id": [ "cg43kau", "cg449cc" ], "score": [ 2, 3 ], "text": [ "It manages communications between the CPU and the RAM and peripheral boards.", "It lets the \"brain\" of the motherboard - the central processing unit or CPU - talk to all the other components of the motherboard like the...
[]
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[ [], [] ]
3aclf8
do animals feel growth pain?
explainlikeimfive
http://www.reddit.com/r/explainlikeimfive/comments/3aclf8/eli5_do_animals_feel_growth_pain/
{ "a_id": [ "csbga8l" ], "score": [ 2 ], "text": [ "[They do](_URL_0_), if they have rapid enough growth like larger dogs. Since most of our pets don't have such rapid growth (cat, birds, fish), presumably they don't feel any pain. " ] }
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[ [ "http://www.labbies.com/dysplasa.htm" ] ]
26mtlv
Why didn't Jordan tried to invade Israel in the 1973 war?
Jordan had the biggest border with Israel at the time and could capture Jerusalem in matter of hours because most Israeli troops were busy repelling attacks from the Syrians and Egyptians. so why didn't they took the bait and attacked?
AskHistorians
http://www.reddit.com/r/AskHistorians/comments/26mtlv/why_didnt_jordan_tried_to_invade_israel_in_the/
{ "a_id": [ "chsm1cr" ], "score": [ 53 ], "text": [ "It was, at least in part, because the Jordanians had cooperated greatly with the Israelis under Hussein around this time.\n\nJordan had always been hesitant to attack Israel. In fact, during the 1967 War, the Israelis believed that the fire comi...
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[]
[ [ "http://www.haaretz.com/news/diplomacy-defense/.premium-1.546843" ] ]
r0kqb
How visually accurate are deep space telescopic images?
My friend recently posted [this](_URL_0_) image with the caption "can't believe this isn't Photoshop!" However, I remember reading that most images received by deep space telescopes aren't visually accurate, and are based off of color coding the light of emissions for different atoms. For instance, the Hubble's photogr...
askscience
http://www.reddit.com/r/askscience/comments/r0kqb/how_visually_accurate_are_deep_space_telescopic/
{ "a_id": [ "c41y2kf" ], "score": [ 7 ], "text": [ "I want to begin by saying that that image is most definitely not a real image. It's an artist's conception.\n\nTo the naked eye, nebulae look gray. You might seen hints of faint color here and there, but it's mostly just gray. Telescopes use long...
[]
[ "http://www.universetoday.com/wp-content/uploads/2008/05/228144main_red-dwarf-flare-full.jpg", "http://hubblesite.org/newscenter/archive/releases/1995/44/image/a/" ]
[ [] ]
22cr8c
What is a soviet? How were they selected?
Lenin and the Bolsheviks had "All power to the soviets!" as a slogan. What the heck is that, who got to decide their composition, and how did they "unify?"
AskHistorians
http://www.reddit.com/r/AskHistorians/comments/22cr8c/what_is_a_soviet_how_were_they_selected/
{ "a_id": [ "cglmr1i" ], "score": [ 25 ], "text": [ "The soviets themselves were Councils, think of them as political units. You can find a brief essay by Soviet Historian Lewis Siegelbaum on them here: _URL_2_\n\n(It's an excellent site for Soviet History in general, as a side note)\n\nFirst it ...
[]
[]
[ [ "https://www.marxists.org/archive/lenin/works/1917/jul/18.htm", "http://soviethistory.macalester.edu/images/Large/1917/aih528.jpg", "http://soviethistory.macalester.edu/index.php?page=subject&SubjectID=1917formsoviets&Year=1917", "http://soviethistory.macalester.edu/index.php?page=subject&...
4r3bak
can you increase the speed of sound by using different gasses?
Is there a gas that moves quicker than Co2, or is the movement of gases by pressure waves a constant force?
explainlikeimfive
https://www.reddit.com/r/explainlikeimfive/comments/4r3bak/eli5can_you_increase_the_speed_of_sound_by_using/
{ "a_id": [ "d4xy8hl" ], "score": [ 23 ], "text": [ "The speed of sound is increased if the density of the gas is lower. For example, in helium, the speed of sound is 1007m/s at atmospheric pressure and 20°C, almost three times as much as in air. In a heavy gas like xenon, it's only 178 m/s.\n\nTh...
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[]
[ [] ]
lgn93
If someone jumped off a cliff as high as the golden gate bridge into a large lake that had a surfactant (soap I guess) poured onto it, would they survive?
askscience
http://www.reddit.com/r/askscience/comments/lgn93/if_someone_jumped_off_a_cliff_as_high_as_the/
{ "a_id": [ "c2sj2cp", "c2sj407", "c2sjrpe", "c2sliu4", "c2sljtn", "c2slt8p", "c2sm1ci", "c2sndo7", "c2snvli", "c2sj2cp", "c2sj407", "c2sjrpe", "c2sliu4", "c2sljtn", "c2slt8p", "c2sm1ci", "c2sndo7", "c2snvli" ], "score": [ 5, 6, 2...
[]
[]
[ [], [], [], [ "http://hyperphysics.phy-astr.gsu.edu/hbase/flobi.html", "http://www.convertunits.com/from/newtons/to/lbs" ], [ "http://en.wikipedia.org/wiki/MythBusters_(2003_season\\)" ], [], [], [], [ "http://www.newyorker.com/archive/2003/10/13/031013fa_fact" ], [], [], ...
mrbxn
Can someone explain how those giant single celled organisms on the seafloor are possible?
My biology teacher told me that there is an upper limit to cell size because of surface area/volume scaling. Also, what about the membrane(s)? My understanding of plasma membranes is that they have more or less the consistency of a soap bubble. I am assuming that there is a cell wall of some sort to compensate for this...
askscience
http://www.reddit.com/r/askscience/comments/mrbxn/can_someone_explain_how_those_giant_single_celled/
{ "a_id": [ "c338h6l", "c338qzt", "c3398gc", "c33d5g1", "c33dgmq", "c338h6l", "c338qzt", "c3398gc", "c33d5g1", "c33dgmq" ], "score": [ 3, 2, 28, 3, 2, 3, 2, 28, 3, 2 ], "text": [ "You will need to be more specific than **\"tho...
[]
[ "http://en.wikipedia.org/wiki/Xenophyophore" ]
[ [], [], [], [], [ "http://en.wikipedia.org/wiki/Slime_mold" ], [], [], [], [], [ "http://en.wikipedia.org/wiki/Slime_mold" ] ]
1cg4sw
According to wikipedia "Current generations of nuclear submarines never need to be refueled throughout their 25-year lifespans"
How much of that is true? The citation doesn't mention anything about 25 years lifespan: _URL_0_
askscience
http://www.reddit.com/r/askscience/comments/1cg4sw/according_to_wikipedia_current_generations_of/
{ "a_id": [ "c9g60jr", "c9g7jvb", "c9g8c6y", "c9gcgz3" ], "score": [ 4, 2, 13, 7 ], "text": [ "The article says it won't need refuelling in the submarine's service lifetime, for which 25 years is a typical figure. In general, nuclear reactors don't have to be refuelled very...
[]
[ "http://www.naval-technology.com/projects/astute/" ]
[ [], [], [], [] ]
1baxy4
why progress bars always hang on 99/100%
explainlikeimfive
http://www.reddit.com/r/explainlikeimfive/comments/1baxy4/eli5_why_progress_bars_always_hang_on_99100/
{ "a_id": [ "c957skp" ], "score": [ 4 ], "text": [ "Progress bar values are basically made up by the developer. For some things they work pretty good. If you are downloading a 100MB file and have finished downloading 70MB then saying you are 70% done is pretty easy. For things like installing a...
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[]
[ [] ]
5vz2mk
Why didn't Italy find Oil in Libya while it was an Italian colony.
I imagine it would have been useful in World War II.
AskHistorians
https://www.reddit.com/r/AskHistorians/comments/5vz2mk/why_didnt_italy_find_oil_in_libya_while_it_was_an/
{ "a_id": [ "de692y0" ], "score": [ 8 ], "text": [ "There were some isolated discoveries during the 1920s that hinted at the possibility of oil deposits in the colony. Wells sometimes produced commercially-negligable amounts of petroleum and natural gas. An Italian geological expedition led by the...
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[ [] ]
wn2fu
About how far away are we from self-powered electronic devices that have batteries that don't need to be recharged?
I'm talking about, for instance, a cell phone with a battery that lasts as long as the expected lifespan of the cell phone itself, without needing a charge. rupert1920 hits it on the head with the automatic quartz mechanism; maybe it's not a battery. Could it be in this lifetime that we'll be able to purchase phones, a...
askscience
http://www.reddit.com/r/askscience/comments/wn2fu/about_how_far_away_are_we_from_selfpowered/
{ "a_id": [ "c5eqfzt" ], "score": [ 4 ], "text": [ "A battery, by definition, converts chemical energy to electrical energy. This means that, unless chemicals are replaced, or energy is put back into the system, a battery _will_ run out.\n\nYou'll find that there are [some designs](_URL_0_) out th...
[]
[]
[ [ "http://en.wikipedia.org/wiki/Seiko_Kinetic_watches", "http://en.wikipedia.org/wiki/Solar-powered_watch" ] ]
1uouqm
Looking for quotes on American Revolution! Can't quite remember
So I read Zinn's *A People's History* quite a while back (I know his book is polarizing here), but I am trying to recall some quotes he cites and I can't find them in the book this time around. I recall him referencing a least once a figure of the revolution essentially warning against 'tyranny' of the majority or eve...
AskHistorians
http://www.reddit.com/r/AskHistorians/comments/1uouqm/looking_for_quotes_on_american_revolution_cant/
{ "a_id": [ "cek9daj", "cek9hrz", "cek9is5" ], "score": [ 2, 2, 2 ], "text": [ "Try /r/tipofmytongue also", "Perhaps one of these two?\n\n\"Nevertheless, to the persecution and tyranny of his cruel ministry we will not tamely submit -- appealing to Heaven for the justice of our...
[]
[]
[ [], [], [] ]
1bpchr
Are sunsets local or global?
When I watch a beautiful sunset (or sunrise), I wonder whether folks in the next time zone will see a similar display or something completely different. So how local is a sunset? Will it evolve and change over the course of latitude? Or is it similar across the globe based on some higher altitude atmospheric phenomena?
askscience
http://www.reddit.com/r/askscience/comments/1bpchr/are_sunsets_local_or_global/
{ "a_id": [ "c98su35", "c98v6ty" ], "score": [ 5, 3 ], "text": [ "Sunrises and Sunsets do vary by where you are on the globe. To start off we can look into why sunsets and sunrises can be red. The blue sky is due to a phenomenon called Rayleigh Scattering. This is were light from the su...
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[]
[ [ "http://photonicswiki.org/images/2/21/Rayleigh_scatter.jpg" ], [ "http://en.wikipedia.org/wiki/File:Lunar_eclipse_optics.jpg", "http://en.wikipedia.org/wiki/Lunar_eclipse" ] ]
3iax2q
why don't we have solar powered phones?
A phone that runs on energy from the sun the way solar powered calculators do. No solar powered phone chargers, an emergency phone that never needs a phone charger and runs purely on solar power.
explainlikeimfive
http://www.reddit.com/r/explainlikeimfive/comments/3iax2q/eli5_why_dont_we_have_solar_powered_phones/
{ "a_id": [ "cuetvnz" ], "score": [ 16 ], "text": [ "Solar panels don't generate nearly enough power. Solar powered calculators only take a tiny amount of power compared to a phone." ] }
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[ [] ]
aufozc
How different were languages between different Native American tribes? If you could bring together an East coast and West coast tribe, would they be able to mostly understand one another?
AskHistorians
https://www.reddit.com/r/AskHistorians/comments/aufozc/how_different_were_languages_between_different/
{ "a_id": [ "eh874qx" ], "score": [ 12 ], "text": [ "The short answer is no.\n\nThere are dozens of major language families throughout the Americas. [Algic](_URL_0_) is the only one found on both the east and west coast of North America, and even the handful of small Algic languages in the west ha...
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[]
[ [ "https://en.wikipedia.org/wiki/Algic_languages#/media/File:Algic_langs.png" ] ]
6bh372
why do we use implants for breast enlargement instead of something biological like stomache fat?
explainlikeimfive
https://www.reddit.com/r/explainlikeimfive/comments/6bh372/eli5_why_do_we_use_implants_for_breast/
{ "a_id": [ "dhmi2lp", "dhmif3u", "dhmmzrk", "dhmwvx3" ], "score": [ 41, 2, 3, 3 ], "text": [ "Fat is a living tissue. Transplants of living tissue are more expensive and have higher risk of complications. Implants are biologically inert and relatively easy to implant.", ...
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[ [], [], [], [] ]
1gbcgw
i want to understand important nutrient information.
I'm overweight, I don't want to be. Aside from calories, I don't know what cholesterol, carbohydrates, etc. are and what roles they play in maintaining health. I have focusing issues, so reading up on this stuff through wikipedia has yielded nothing of value. Simplified answers seem to be my only choice.
explainlikeimfive
http://www.reddit.com/r/explainlikeimfive/comments/1gbcgw/eli5_i_want_to_understand_important_nutrient/
{ "a_id": [ "caik7st" ], "score": [ 2 ], "text": [ "Carbohydrates are sweet and starchy things, examples are: sugar, flour, bread, rice, corn, etc.\n\nFats are oils and greases. If it makes your fingers a little greasy when you touch it, it's probably got a LOT of fat in it.\n\nFor weight loss, i...
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[ [] ]
12gb7c
how did the uk nhs system work, what did the recent reform bill do to the system and what are the reasons for it?
I'm struggling to understand - I hear a lot about 'privatising' but can't really see how it works - why is competition good in healthcare sector? Pros & cons? And if it is really as bad as everyone says it is, why did the government implement it?
explainlikeimfive
http://www.reddit.com/r/explainlikeimfive/comments/12gb7c/eli5_how_did_the_uk_nhs_system_work_what_did_the/
{ "a_id": [ "c6utdvh", "c6utjir", "c6utp8n", "c6utu4y", "c6uwk14", "c6v0sf1" ], "score": [ 7, 8, 21, 10, 3, 3 ], "text": [ "There are some [great articles about the NHS reforms](_URL_2_) at the British Medical Journal's website.\n\n > And if it is really as ...
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[]
[ [ "http://www.guardian.co.uk/politics/reality-check-with-polly-curtis/2012/jan/19/health-bill-private-patients", "http://socialinvestigations.blogspot.co.uk/2012/02/nhs-privatisation-compilation-of.html", "http://journals.bmj.com/site/nhsreforms/index.xhtml", "http://theglobalawakening.wordpress.com...
6y6ey2
how do physicists "solve" equations?
I was watching Interstellar the other day and Michael Caine's character is tasked to "solve gravity." The work was a huge equation on a bunch of blackboards. They talked about running iterations and that it only has to work once. What does that mean, how does one solve those science equations like E= mc^2 ? Thanks.
explainlikeimfive
https://www.reddit.com/r/explainlikeimfive/comments/6y6ey2/eli5_how_do_physicists_solve_equations/
{ "a_id": [ "dml0fn0", "dml119w" ], "score": [ 2, 5 ], "text": [ "Solving an equation is where you know the equation in one form, and want to rewrite it to another form, so it's easier to calculate the value of one of it's variables.\n\nIn your example of E = mc^2, say you know the energy ...
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[]
[ [], [] ]
5ycfrv
Sound of a Baroque Era Classical Pieces sound then then versus now?
Good evening and thank you for your time in advance! I was reading up on Piano tuning recently, and I came across this: _URL_0_ In it, it says that in the Baroque Era, A = 415 Hz and A# = 440 Hz. Today, A = 440 Hz, which to me says that all instruments were pitched up by about a half step. To me, the logcial conclu...
AskHistorians
https://www.reddit.com/r/AskHistorians/comments/5ycfrv/sound_of_a_baroque_era_classical_pieces_sound/
{ "a_id": [ "deppmjw" ], "score": [ 2 ], "text": [ "It's not that simple.\n\nSee, there was [no consensus on a pitch reference](_URL_1_) to the level of precision we discuss these days. There was [eight foot pitch](_URL_0_) and people used whistles and so on to have pitch references, but there was...
[]
[ "https://en.wikipedia.org/wiki/A440_(pitch_standard)" ]
[ [ "https://en.wikipedia.org/wiki/Eight-foot_pitch", "http://www.dolmetsch.com/musictheory27.htm#chartofpitch" ] ]
dhognl
why do nuclear explosions take the form of a shroom?
explainlikeimfive
https://www.reddit.com/r/explainlikeimfive/comments/dhognl/eli5_why_do_nuclear_explosions_take_the_form_of_a/
{ "a_id": [ "f3p7ba8", "f3p7k11", "f3p7yko" ], "score": [ 9, 5, 3 ], "text": [ "It's because of the air rise up. The center of the explosion is really hot, so the air expanses and it become lighter than the cold air above, so it starts rising. Then it drags the cold air around the ...
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[]
[ [], [], [] ]
1o12kv
Historically, why did England dominate Ireland and not the other way around?
AskHistorians
http://www.reddit.com/r/AskHistorians/comments/1o12kv/historically_why_did_england_dominate_ireland_and/
{ "a_id": [ "ccnxuaa" ], "score": [ 2 ], "text": [ "I'm in a History of Ireland course right now, and we've already gone over a lot of the answer for this. England started \"dominating\" Ireland with the Norman Invasion. The problem with calling it a domination is that an Irish king, MacMurrough...
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[ [] ]
1ex4rb
difference between several types of transistors?
What is the difference between MOSFET; PMOS, NMOS and BJT's? What to they do?
explainlikeimfive
http://www.reddit.com/r/explainlikeimfive/comments/1ex4rb/eli5_difference_between_several_types_of/
{ "a_id": [ "ca4t7xn" ], "score": [ 5 ], "text": [ " > What is the difference between MOSFET; PMOS, NMOS and BJT's?\n\nFET transistors operate on electrical field, which because you're 5 we're going to just say is the same thing as voltage. Basically, with a MOSFET, it's the *voltage* between \"g...
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[ [] ]
19xhbd
Was there a central minting authority responsible for standardization of Roman currency?
AskHistorians
http://www.reddit.com/r/AskHistorians/comments/19xhbd/was_there_a_central_minting_authority_responsible/
{ "a_id": [ "c8s7vx8" ], "score": [ 8 ], "text": [ "There were several dozen mints located around the Empire in various cities, the first and most important of these was in Rome at the temple of Juno Moneta, she was an aspect of the Goddess Juno who was credited with looking after the funds of the...
[]
[]
[ [ "http://www.britishmuseum.org/explore/highlights/highlight_objects/cm/s/silver_denarius_juno_moneta.aspx" ] ]
5onq5y
why do we have two lungs instead of one large lung?
explainlikeimfive
https://www.reddit.com/r/explainlikeimfive/comments/5onq5y/eli5_why_do_we_have_two_lungs_instead_of_one/
{ "a_id": [ "dckpjkj" ], "score": [ 5 ], "text": [ "Redundancy. \n\nIt's an evolutionary advantage to be able to lose one lung, one hand, one kidney, one teste and still function. The energy needed to run two smaller v one large is basically the same. \n\nYou hear about people with a collapsed lun...
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[ [] ]
dc2nh0
joint cracking
explainlikeimfive
https://www.reddit.com/r/explainlikeimfive/comments/dc2nh0/eli5_joint_cracking/
{ "a_id": [ "f25knom", "f25l88j", "f25sdgk" ], "score": [ 3, 2, 2 ], "text": [ "While still debateded, but we do know that carbon dioxide bubbles form in the joint cavity fluid, which then as you move your joint, would sometimes collapse.\n\nWhen the bubbles pop, you hear that dist...
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[]
[ [], [ "https://en.wikipedia.org/wiki/Cracking_joints" ], [] ]
5f3374
Hi there, could anybody help identify this WWI revolver?
Hi guys, my gran has this gun that has been sitting around in her house for the past 40 years and she's just discovered it recently. It's from her mothers uncle who fought in WWI, could anyone help identify this? She wants to know if it's fully operational in the state that it is because if it is, she wants to hand it...
AskHistorians
https://www.reddit.com/r/AskHistorians/comments/5f3374/hi_there_could_anybody_help_identify_this_wwi/
{ "a_id": [ "daied4l" ], "score": [ 2 ], "text": [ "I am afraid that this is going to be a very difficult one to identify, unless there are some markings on it which do not show in any of your photographs. This appears to be a double-action only revolver, with several strange aspects to it. Gene...
[]
[ "http://m.imgur.com/a/s63eP" ]
[ [] ]
dd20xu
how does augmented reality work? looking for more of the technical aspect.
explainlikeimfive
https://www.reddit.com/r/explainlikeimfive/comments/dd20xu/eli5_how_does_augmented_reality_work_looking_for/
{ "a_id": [ "f2dqde7" ], "score": [ 3 ], "text": [ "By sampling a 3D space in the real world using an array of sampling technologies it simply places digital assets within a virtualized space of matching proportions in a convincing manner creating the illusion the object is physically present.\n\n...
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[ [] ]
2ntaat
What was Mexico and Canada's reaction to the American civil war? Were there any foreign volunteers or mercanaires?
Also, did Liberia have any position?
AskHistorians
http://www.reddit.com/r/AskHistorians/comments/2ntaat/what_was_mexico_and_canadas_reaction_to_the/
{ "a_id": [ "cmgqsde", "cmgs324", "cmgtad9", "cmhamym", "cmhoenp" ], "score": [ 120, 626, 19, 3, 2 ], "text": [ "Mexico was busy fighting France. The Cinco de Mayo holiday originated around the same time, after the Battle of Puebla, and even spread to camps in the ...
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[]
[ [], [ "http://opinionator.blogs.nytimes.com/2012/07/02/brothers-in-arms/", "http://opinionator.blogs.nytimes.com/2011/04/26/land-pirate/", "http://opinionator.blogs.nytimes.com/2012/12/11/the-fighting-irish-brigade/", "http://opinionator.blogs.nytimes.com/2012/01/07/lincolns-french-toast/", "h...
5um071
why do elevators decide to wait at the floors they do?
explainlikeimfive
https://www.reddit.com/r/explainlikeimfive/comments/5um071/eli5_why_do_elevators_decide_to_wait_at_the/
{ "a_id": [ "ddv0lxc", "ddv1065", "ddv6ash" ], "score": [ 2, 3, 2 ], "text": [ "Most wait at the floor they are left. But some might be smart as to go back to the ground level so people can get to their workplace quicker and have to wait less to fetch one.", "The simplest solut...
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[]
[ [], [], [] ]
6z1t2f
how do we not notice rubber on the roads if tires slowly wear down on them?
Why can't we take our hand, touch the road, and feel rubber? Might be a silly question, but this question got me thinking in the shower this morning.
explainlikeimfive
https://www.reddit.com/r/explainlikeimfive/comments/6z1t2f/eli5_how_do_we_not_notice_rubber_on_the_roads_if/
{ "a_id": [ "dmrtzh5", "dmrxrts", "dms687v" ], "score": [ 10, 24, 2 ], "text": [ "The quantities are super small and it doesnt stick to the road so well. If you put your hand to the road you may feel dust, and that dust is at least partially rubber.\n\nIf it helps you can visualize...
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[ [], [], [] ]
4bpsmf
in every crime show it's a different profession investigating and solving crimes. who actually does it in real life?
Like CSI vs SVU
explainlikeimfive
https://www.reddit.com/r/explainlikeimfive/comments/4bpsmf/eli5_in_every_crime_show_its_a_different/
{ "a_id": [ "d1bby6f", "d1bcqzo" ], "score": [ 3, 2 ], "text": [ "When crimes are investigated there are different professions involved. \n\nThere are your standard beat cop who is the first to respond. Then there are specialist cops called detectives who are assigned depending on the type...
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[]
[ [], [] ]
26gy8k
How did people make coffee in the days before electricity?
I assumed everyone just used a french press until my grandfather said he had never seen one.
AskHistorians
http://www.reddit.com/r/AskHistorians/comments/26gy8k/how_did_people_make_coffee_in_the_days_before/
{ "a_id": [ "chqz00d" ], "score": [ 8 ], "text": [ "Turkish coffee is made by heating a pot of water, coffee, and usually some sugar and spices until it boils and then quickly removing it from the heat source after it's begun to boil. [Here's a video.](_URL_1_)\n\nThere's also 'cowboy coffee' whic...
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[]
[ [ "http://www.youtube.com/watch?v=c_YqnZUOFQc", "http://www.youtube.com/watch?v=OOaI8JC1_EE" ] ]
2x8foa
When astronomers say something will happen in x amount if time, to something very far away, do they mean when it will actually happen or just when the light it emits gets to us?
Here's an example of what I mean, Say there is a star 2 thousand lightyears away and we have predicted that it will die in 1 thousand years. Is that death when it happens or when we will see it?
askscience
http://www.reddit.com/r/askscience/comments/2x8foa/when_astronomers_say_something_will_happen_in_x/
{ "a_id": [ "coywcb9" ], "score": [ 3 ], "text": [ "Usually, when talking about future events, astronomers talk about when we will observe that event. So, in your example, in our reference frame, we will observe the star's death 1,000 years from now. However, in the star's reference frame, the eve...
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[ [] ]
3yrnje
Mechanics: Mathematically, what is the thought process behind moment of inertia and why is it used in mechanics of materials?
I think that a lot of engineers just power through their mechanics of materials class, but this seems to be a concept that underlies everything we do. I can rattle off a few equations off the top of my head, but what is really happening kind of perplexes me. It's just this number we get that helps us to describe how st...
askscience
https://www.reddit.com/r/askscience/comments/3yrnje/mechanics_mathematically_what_is_the_thought/
{ "a_id": [ "cyghlp8", "cygxekm" ], "score": [ 2, 5 ], "text": [ "_URL_0_\n\nThe integral is basically summing up the individual moments of inertia for each differential mass element of the object, treating them as tiny point masses. And the moment for a point mass is mr^2 .", "The \"m...
[]
[]
[ [ "http://hyperphysics.phy-astr.gsu.edu/hbase/mi.html" ], [] ]
aj3a1z
why is stagnant water unsafe to swim in?
So I saw a TIL post about a sea that is mostly stagnant, making it very unsafe to swim in (there was a comment about it). Why is that?
explainlikeimfive
https://www.reddit.com/r/explainlikeimfive/comments/aj3a1z/eli5_why_is_stagnant_water_unsafe_to_swim_in/
{ "a_id": [ "eescd3x", "eesdex0" ], "score": [ 9, 2 ], "text": [ "Bad things grow in stagnant water like bacteria and parasites. If you get into the water, there’s a good chance they’ll get into you...", "In stagnant water all kinds of interesting biological phenomena are developing. T...
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[ [], [] ]
1gw5ru
how do politions who aren't in power get paid?
More looking at the UK here, but I'm happy hearing from any country.
explainlikeimfive
http://www.reddit.com/r/explainlikeimfive/comments/1gw5ru/eli5_how_do_politions_who_arent_in_power_get_paid/
{ "a_id": [ "caog7px", "caotlxq" ], "score": [ 3, 2 ], "text": [ "They are paid for public appearances, become paid lobbyists, do work like writing books or editorials in papers, work for political organizations, etc etc. There are a lot of positions in politics that don't necessarily invo...
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[ [], [] ]