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21g1vp
How did the Japanese & Germans plan on getting along? (WWII)
So lets say the German expansion in WWII was not stopped in Europe and ended up going to Asia eventually meeting with the Japanese front that was expanding Westward. Wouldn't the Japanese not meet what the Germans considered to be ideal/other way around? I could have all of this wrong and they could have just both be...
AskHistorians
http://www.reddit.com/r/AskHistorians/comments/21g1vp/how_did_the_japanese_germans_plan_on_getting/
{ "a_id": [ "cgcqhsh" ], "score": [ 6 ], "text": [ "Hey, there! How the Germans and the Japanese got along with each other is actually a pretty frequent question, and I'm surprised that it didn't find its way into our [Popular Questions section](_URL_5_) yet. Some of the answers you're looking for...
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[ [ "http://www.reddit.com/r/AskHistorians/wiki/wwii#wiki_axis_post-war_plans", "http://www.reddit.com/r/AskHistorians/comments/11xslj/did_the_japanese_or_italians_have_any_knowlege_of/", "http://www.reddit.com/r/AskHistorians/comments/15yh9d/how_did_nazi_germany_justify_their_alliance_with/", "http:/...
ceno1f
when you are having joint pain and you spray pain relief on it, what actually happens?
explainlikeimfive
https://www.reddit.com/r/explainlikeimfive/comments/ceno1f/eli5_when_you_are_having_joint_pain_and_you_spray/
{ "a_id": [ "eu3scv3" ], "score": [ 3 ], "text": [ "Generally, it's a topical anesthetic, like menthol. All it does is penetrate the skin to the nerves and deaden the nerve's pain signals for a small amount of time." ] }
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[ [] ]
tse6h
- biologically, how to vine plant tendrils "sense" when they are in contact with something, and how they generate the mechanical force to coil themselves around it?
No one in AskScience either knew or cared enough to answer, hoping someone here might...
explainlikeimfive
http://www.reddit.com/r/explainlikeimfive/comments/tse6h/eli5_biologically_how_to_vine_plant_tendrils/
{ "a_id": [ "c4pd9wz" ], "score": [ 4 ], "text": [ "The vine twines because the cells on one side grow faster than the cells on the opposite side. When the growing tip of the vine touches an obstacle, such as a twig, this stimulates the cells of the vine on the side opposite the twig to grow faste...
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[ [ "http://indianapublicmedia.org/amomentofscience/how-do-vines-twist-and-turn/" ] ]
1xbfao
why is it that sometimes i can feel my heart beat so strongly that it almost hurts but my blood pressure is always normal when i check it?
This always bothers me and sometimes I lose sleep because of it.
explainlikeimfive
http://www.reddit.com/r/explainlikeimfive/comments/1xbfao/why_is_it_that_sometimes_i_can_feel_my_heart_beat/
{ "a_id": [ "cf9u89a" ], "score": [ 2 ], "text": [ "Are you feeling just a strong heartbeat, or a fast heartbeat? The latter can be some form of tachycardia (assuming you are not talking about when you are exercising)." ] }
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[ [] ]
21je1z
why does the us have mailboxes instead of letter boxes?
I would say most houses in the world simply have a letter box on the door to put letters / small parcels through. Why does America (and some other country's) instead have a box with a flap on a stick?
explainlikeimfive
http://www.reddit.com/r/explainlikeimfive/comments/21je1z/eli5_why_does_the_us_have_mailboxes_instead_of/
{ "a_id": [ "cgdlgmh", "cgdljby", "cgdllho", "cgdlmh2" ], "score": [ 5, 2, 2, 8 ], "text": [ "So the mail carriers don't have to get out of their vehicles.", "My house does have a letter box in the door. But it's an older house.\n\nFor many newer houses, the USPS will r...
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[ [], [], [], [] ]
joze1
why do you need to make two holes in a can for liquid to pour properly?
If I only make one hole in a can, the liquid just gets stuck. Once I popped open another hole with the can opener, it came out easily. What gives? P.S. if it makes any difference, I was opening a can of carnation milk.
explainlikeimfive
http://www.reddit.com/r/explainlikeimfive/comments/joze1/eli5_why_do_you_need_to_make_two_holes_in_a_can/
{ "a_id": [ "c2dx3bj", "c2dx3pn", "c2dx3bj", "c2dx3pn" ], "score": [ 11, 2, 11, 2 ], "text": [ "When you pour something out of a can, and you're standing there holding the empty can, guess what? It's not empty!\n\nReally. It's not. Instead of being full of milk, or whatever...
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[ [], [], [], [] ]
71rr6z
I know a fair bit about Swiss Pikemen, but why where they Swiss, and why couldn't their techniques be copied?
AskHistorians
https://www.reddit.com/r/AskHistorians/comments/71rr6z/i_know_a_fair_bit_about_swiss_pikemen_but_why/
{ "a_id": [ "dndg8ow", "dneqf5u" ], "score": [ 2, 8 ], "text": [ "How do the Spanish Tercios, which had pike formations in them, come to play into this Swiss and Landsknecht story? Where they a later evolution? A separate innovation? A kind of landsknecht?", "You might be interested in...
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[]
[ [], [ "https://www.reddit.com/r/AskHistorians/comments/3y0fbd/how_come_in_history_the_swiss_were_known_for/cy9hmtj/", "https://sv.wikipedia.org/wiki/Fil:Desembarcoislasterceiras.jpg" ] ]
2yujpr
Is blue cheese antibiotic?
I read that blue cheese contains penicillin. Does this mean it has antibiotic properties?
askscience
http://www.reddit.com/r/askscience/comments/2yujpr/is_blue_cheese_antibiotic/
{ "a_id": [ "cpeoa6q" ], "score": [ 3 ], "text": [ "**Where does penicillin come from?**\nPenicillin is produced by some (but not all) fungal species in the *Penicillium* genus. Wild-type fungi produce relatively low levels of penicillin that are not particularly useful *in vivo* as antibiotics (a...
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[ [ "http://www.ncbi.nlm.nih.gov/pmc/articles/PMC123731/", "http://www.sciencedirect.com/science/article/pii/S0032959299000527#", "http://aem.asm.org/content/15/4/754.full.pdf+html" ] ]
1eo4jf
What studies have there been regarding the accuracy of radiocarbon dating?
askscience
http://www.reddit.com/r/askscience/comments/1eo4jf/what_studies_have_there_been_regarding_the/
{ "a_id": [ "ca23pa1", "ca29sv2" ], "score": [ 7, 3 ], "text": [ "It's a well studied phenomenon. I would suggest starting in the [reference list](_URL_0_) and [external links section](_URL_1_) of the Wikipedia article.", "According to Google Scholar there are [334,000](_URL_0_) pasper...
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[]
[ [ "http://en.wikipedia.org/wiki/Radiocarbon_dating#References", "http://en.wikipedia.org/wiki/Radiocarbon_dating#External_links" ], [ "http://scholar.google.fr/scholar?hl=en&q=carbon+dating&btnG=&as_sdt=1%2C5&as_sdtp=" ] ]
829dwc
blockchain
explainlikeimfive
https://www.reddit.com/r/explainlikeimfive/comments/829dwc/eli5_blockchain/
{ "a_id": [ "dv8fa3i", "dv8fr1w", "dv8g7bz" ], "score": [ 2, 2, 2 ], "text": [ "Blockchain is just a ledger that everyone in the world uses for a single currency. Different people (miners) add to the ledger when a transaction occurs. If you send money from your account X to your fr...
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[ [], [], [] ]
9majiz
During 321-297 BCE, Chandragupta Maurya seemed to be such a powerhouse of a leader, in that he conquered almost all of India and pushed out Seleucus. Why wasn’t he able to conquer the Tamil Kings?
AskHistorians
https://www.reddit.com/r/AskHistorians/comments/9majiz/during_321297_bce_chandragupta_maurya_seemed_to/
{ "a_id": [ "e7fm94n" ], "score": [ 3 ], "text": [ "I think you might be overplaying the extent of the Maurya empire during Chandragupta’s reign. His expansion of the original nanda empire was mainly to northwest. Not to south. His descendants expanded it to central and southern India. \n\nIt fell...
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6u9xp1
why can't you really jump after you've been on a trampoline?
explainlikeimfive
https://www.reddit.com/r/explainlikeimfive/comments/6u9xp1/eli5_why_cant_you_really_jump_after_youve_been_on/
{ "a_id": [ "dlr24nu", "dlr2897", "dlruj86" ], "score": [ 7, 7, 2 ], "text": [ "The same reason you feel like you're flying after you get off a treadmill, just the opposite. On a treadmill, you put in a great deal of effort with essentially zero physical movement, and when you're o...
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[]
[ [], [], [] ]
6h48kn
why is oatmeal so hard to clean from eating surfaces?
explainlikeimfive
https://www.reddit.com/r/explainlikeimfive/comments/6h48kn/eli5_why_is_oatmeal_so_hard_to_clean_from_eating/
{ "a_id": [ "diveqzx" ], "score": [ 4 ], "text": [ "As oatmeal cooks, it develops a very sticky glutinous consistency. If that's allowed to dry on a dish, it's very hard to get off. (Dried oatmeal with milk in it is even worse, and dried oatmeal with milk *and* sugar is as bad as dried-on food eve...
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37rt5f
How did the Green Revolution save a billion lives?
Did it save lives or just provide food for safe population growth?
AskHistorians
http://www.reddit.com/r/AskHistorians/comments/37rt5f/how_did_the_green_revolution_save_a_billion_lives/
{ "a_id": [ "crpudp7" ], "score": [ 2 ], "text": [ "I wouldn't say it saved lives as much as provided a way to continue stable population growth and prevent food shortages.\n\nThe increase in production from use of technology and new farming methods allowed people to produce more at a time when co...
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[ [ "http://www.economist.com/news/briefing/21601815-another-green-revolution-stirring-worlds-paddy-fields-bigger-rice-bowl" ] ]
2c5i0z
why does it feel like you actually produce more poop with a high fiber diet, rather than just pooping more regularly?
explainlikeimfive
http://www.reddit.com/r/explainlikeimfive/comments/2c5i0z/eli5_why_does_it_feel_like_you_actually_produce/
{ "a_id": [ "cjc3vg2" ], "score": [ 4 ], "text": [ "Partly because you do. Fiber isn't digested so you poop it out \"minimally transformed\". This makes it more voluminous than non-fibrous poop." ] }
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6pppd7
why are there different variants of the same phone model for different countries?
Why is that you can only use a particular phone in one country and the company exclusively produces variants of the same model for different countries? Wouldn't it make more sense to manufacture a standardized variant that can be sold anywhere?
explainlikeimfive
https://www.reddit.com/r/explainlikeimfive/comments/6pppd7/eli5_why_are_there_different_variants_of_the_same/
{ "a_id": [ "dkr7b52" ], "score": [ 2 ], "text": [ "Exclusive varients and other version of region locking prevents the people of one country buying up a product where it's cheapest.\n\nMany products have variable prices in different countries. This depends on the particular nation's currency exch...
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e34qu8
What is the 'darkest' place on the surface of the earth - in terms of light pollution?
(with the 'surface' part I just mean that it's a spot where the sky/universe can be seen, not like any cave or something like this)
askscience
https://www.reddit.com/r/askscience/comments/e34qu8/what_is_the_darkest_place_on_the_surface_of_the/
{ "a_id": [ "f926k93", "f92jl5y", "f94gacf" ], "score": [ 21, 9, 6 ], "text": [ "[This website](_URL_0_) has a good map that shows light pollution levels all over the world. You can use it to find dark sites near you.", "There's a point in the Pacific ocean that's the farthest ...
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[]
[ [ "https://darksitefinder.com/maps/world.html" ], [], [] ]
6wp6s8
intel's core processor differences and what is skylake and kaby lake
explainlikeimfive
https://www.reddit.com/r/explainlikeimfive/comments/6wp6s8/eli5_intels_core_processor_differences_and_what/
{ "a_id": [ "dm9q8oy" ], "score": [ 4 ], "text": [ "Those are \"code names\" for different processor generations. Kaby Lake was released in 2016, Sky Lake in 2015. \n\nIntel produced processors on a \"tick-tock\" cycle. That means every tick of the clock (12-18 months) they change the architecture...
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129hyp
I have a Question did English long bowman wear hoods? I always see them depicted as wearing them in films and books and such
Why did they wear them if they did?
AskHistorians
http://www.reddit.com/r/AskHistorians/comments/129hyp/i_have_a_question_did_english_long_bowman_wear/
{ "a_id": [ "c6t9d4n", "c6takzz", "c6tbc3s" ], "score": [ 14, 35, 8 ], "text": [ "Early on in their history, such as when the Welsh first used longbows against the English yes, since they were mostly peasants and not trained soldiers. Later in English history most longbowmen would...
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[ [], [ "http://195.224.149.148/SB/ww1_helmet_1.jpg" ], [ "http://en.wikipedia.org/wiki/Chaperon_(headgear)" ] ]
1nx11g
Have extremophiles always been extremophiles?
That is, are the ancestor of those bacteria and other weird lifeforms that live in the harshest environments on earth extremophiles as well or did all extremophiles evolve from organism that lived in more friendly environments? How much do we even know about extremophile evolution?
askscience
http://www.reddit.com/r/askscience/comments/1nx11g/have_extremophiles_always_been_extremophiles/
{ "a_id": [ "ccmu3r2", "ccn0285" ], "score": [ 7, 2 ], "text": [ "We know a little about extremophile evolution by tracking the 16S ribosomal RNA in different species (or similar techniques). This allows us to map the phylogeny of different species, and so far seems to point at the fact th...
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[ [], [] ]
ba207h
What is the biological basis of anhedonia / depression?
What is the biological basis of anhedonia / depression? "Anhedonia occurs in roughly 70% of people with a major depressive disorder.[2] Anhedonia is a core symptom of major depressive disorder; therefore, individuals experiencing this symptom can be diagnosed with depression, even in the absence of low/depressed mood...
askscience
https://www.reddit.com/r/askscience/comments/ba207h/what_is_the_biological_basis_of_anhedonia/
{ "a_id": [ "ek945ml", "eka8wdt" ], "score": [ 3, 9 ], "text": [ "I don't know very much about anhedonia, but since no one has answered yet maybe the little I know may be of interest. Some people in my lab look at anhedonia in the context of genetics, and I know there are studies that have...
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[]
[ [ "https://www.ncbi.nlm.nih.gov/pmc/articles/PMC6089928/" ], [ "https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3274778/", "https://www.ncbi.nlm.nih.gov/pubmed/29446381", "https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5374329/", "https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4309382/" ] ]
123gi8
In the case of excess nutrients, why does the body store some and excrete others?
For example, in the case of dietary supplements such as vitamin tablets, the body often doesn't use all the nutrients provided, and excretes the excess. However, on the other hand, in the case of more readily-available nutrients like fats and sugars, the body tends to pack on as much as possible, even if it may be more...
askscience
http://www.reddit.com/r/askscience/comments/123gi8/in_the_case_of_excess_nutrients_why_does_the_body/
{ "a_id": [ "c6rwcxd" ], "score": [ 2 ], "text": [ "That's a rather complicated question. I'll attempt to answer it in three parts: Energy Sources (Fats, Sugars, and Proteins), Vitamins, and Minerals.\n\n**Energy Sources:** Your body needs a constant supply of energy to keep working. Your muscles ...
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2f5k33
why is self-destructive behaviour so much fun?
Why do humans get such a thrill out of doing things that severely damage the body? Why do we feel the need to drink, destroying our livers and making us age faster? Why do we love to fight and get hurt, and why does it give us such a rush? Why do some of us feel the need to do drugs in order to feel good? Why do some o...
explainlikeimfive
http://www.reddit.com/r/explainlikeimfive/comments/2f5k33/eli5_why_is_selfdestructive_behaviour_so_much_fun/
{ "a_id": [ "ck648ra", "ck65q3f" ], "score": [ 2, 3 ], "text": [ "As someone who is Straight Edge I am also curious about the answer to this.", "It is related to the chemicals being released when self-destructive behavior occurs.\n\nExamples:\n\n- Mostly: adrenaline. Doing something ex...
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[ [], [ "http://www.drugabuse.gov/publications/addiction-science/why-do-people-abuse-drugs/nearly-all-drugs-abuse-increase-dopamine-neurotransmission" ] ]
3lvs17
why does killing 124 people like gm did end up with a smaller fine than circumventing emission laws?
GM continued to put faulty ignition in cars after knowing they were dangerous netting 124 deaths, a few hundred injured resulting in a $900,000,000 fine. VW cheated on their emissions test killing no one, resulting in a possible $18,000,000,000. I understand emission laws are important to everyone's health, but I re...
explainlikeimfive
https://www.reddit.com/r/explainlikeimfive/comments/3lvs17/eli5_why_does_killing_124_people_like_gm_did_end/
{ "a_id": [ "cv9sx4z" ], "score": [ 3 ], "text": [ "There's not a whole lot enforcing the consistency of fines. On its own, neither of those fines is obviously unreasonable. It's just that when they're next to each other it looks wrong.\n\nAlso, personally I don't think GM should have been fined a...
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k18dv
how does an elisa kit for antibody and antigen detection work/how do you do it?
_URL_0_ (wikipedia explains it complicatedly)
explainlikeimfive
http://www.reddit.com/r/explainlikeimfive/comments/k18dv/eli5_how_does_an_elisa_kit_for_antibody_and/
{ "a_id": [ "c2gqhzm", "c2gqhzm" ], "score": [ 3, 3 ], "text": [ "You have an antibody - a molecule that has a very specific binding to a particular molecule - fixed to the bottom of your well. You throw in your sample to be analyzed, and your target analyte will be caught by the antibodie...
[]
[ "http://en.wikipedia.org/wiki/ELISA" ]
[ [], [] ]
bwlued
if a gigantic tsunami is coming at you, why can't you just dive into it like a normal wave and swim to the top?
[deleted]
explainlikeimfive
https://www.reddit.com/r/explainlikeimfive/comments/bwlued/eli5_if_a_gigantic_tsunami_is_coming_at_you_why/
{ "a_id": [ "epyg2l7", "epygdqu", "epyh4oa", "epyicic", "epyizgr", "epyj65m" ], "score": [ 7, 5, 7, 5, 2, 4 ], "text": [ "1) you cant swim to the top. 2) even if you did, it would then proceed to hurl you against the street or beach or building. 3) tsunamis ...
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[ [], [], [], [], [], [] ]
51p0t4
Why do engines run more efficiently when hot?
My car gets get at least ten miles per gallon more when the engine is at optimum operating temperature. Why is this? I understand the oil may become less viscous but would that have much of effect? I can't find any good answers on google. Edit: I have a prius so 10 miles per gallon is only a 20% increase.
askscience
https://www.reddit.com/r/askscience/comments/51p0t4/why_do_engines_run_more_efficiently_when_hot/
{ "a_id": [ "d7dw7oh" ], "score": [ 10 ], "text": [ "The parts expand and contract with heat and are designed to be at optimum clearance at designed running temp,your car runs in an enriched mode(choke) when cold because gasoline does not like to vaporize when cold,oil viscosity, automatic trans f...
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2vm3ee
Since a chicken can lay one egg about once a day does that mean it can lay a fertilized egg everyday if the chicken mates on a daily basis?
Sorry for saying day/daily a lot.
askscience
http://www.reddit.com/r/askscience/comments/2vm3ee/since_a_chicken_can_lay_one_egg_about_once_a_day/
{ "a_id": [ "coj0pqe" ], "score": [ 21 ], "text": [ "Yes, but if you leave the eggs in the nest then when a few have built up the chicken stops laying and gets clucky and sits on the eggs until they hatch.\n\n" ] }
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2simo8
how can companies like zipcar and enterprise car share buy permanent street parking spots?
I'm not talking about spots in private lots, but actual city street parking spaces. I've always wondered how they can legally buy them from the city when this option clearly isn't open to individuals.
explainlikeimfive
http://www.reddit.com/r/explainlikeimfive/comments/2simo8/eli5_how_can_companies_like_zipcar_and_enterprise/
{ "a_id": [ "cnpsm8w", "cnptv4u" ], "score": [ 3, 2 ], "text": [ "Business, especially large ones, can negotiate with cities a lot better than individuals can. In the case for something like Zipcar or Enterprise Car Share, they could (and probably do) make a case of why allowing them this ...
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[ [], [] ]
34gcur
When did lack of sewer systems start to have a significant impact on human health? Where were early sewer systems implemented and how did they work?
AskHistorians
http://www.reddit.com/r/AskHistorians/comments/34gcur/when_did_lack_of_sewer_systems_start_to_have_a/
{ "a_id": [ "cquf4k3" ], "score": [ 2 ], "text": [ "On your second question, check out this post: it has a bit of info on 19th c UK, plus links to a whole bunch of posts on sewage systems in various cultures through time\n\n* [Before sewers were a common thing in city's how would people get rid of...
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[]
[ [ "http://www.reddit.com/r/AskHistorians/comments/2cul8b/before_sewers_were_a_common_thing_in_citys_how/" ] ]
c6lcz4
how does the negative photo illusion work?
look 30 seconds to negative color photo and when you look at the wall it is in full color
explainlikeimfive
https://www.reddit.com/r/explainlikeimfive/comments/c6lcz4/eli5_how_does_the_negative_photo_illusion_work/
{ "a_id": [ "esa3ow1", "esa3wo1" ], "score": [ 2, 2 ], "text": [ "I'm not sure but I'll try to answer, your eyes has three types of cone cell, red, green and blue. negative of any image is just the complement of the three primary Colors (RGB). so when you state at any image long enough, th...
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[ [], [] ]
40af0l
Russian settlement in Baltic states after the WWII
You'd often see people claim that USSR settled two out of its three Baltic republics of Estonia and Latvia with people from other Soviet republic (but mostly Russians) with the intention to dilute local populations with more reliable element. Where does this theory come from and how much of it is true? It's surprising...
AskHistorians
https://www.reddit.com/r/AskHistorians/comments/40af0l/russian_settlement_in_baltic_states_after_the_wwii/
{ "a_id": [ "czkfd1u", "cyt80gf" ], "score": [ 2, 3 ], "text": [ "1) Forest Brother resistance movement was indeed stronger in Lithuania, but fewer Russian immigrants wasn't caused by that fact. First of all, the 1940s and 1950s didn't see a huge influx of Russians anyways, only the army a...
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[]
[ [], [ "http://www.historycommission.ee/", "http://demoscope.ru/weekly/ssp/sng_nac_89.php?reg=15", "http://www.mnemosyne.ee/hc.ee/pdf/conclusions_en_1940-1941.pdf", "http://www.estonica.org/en/Deportation_of_March_1949/", "http://demoscope.ru/weekly/ssp/sng_nac_70.php?reg=15", "http://www.e...
3vbq45
when searching for jobs online, i almost never see an amount (whether hourly or salaried) of how much a company will pay an individual who actually gets the job. why is that so?
explainlikeimfive
https://www.reddit.com/r/explainlikeimfive/comments/3vbq45/eli5_when_searching_for_jobs_online_i_almost/
{ "a_id": [ "cxm2mqh", "cxm6ba1", "cxm7zt5", "cxma33q", "cxmajkr" ], "score": [ 21, 6, 7, 2, 2 ], "text": [ "they want to get away with paying the minimum amount they can, so they usually ask you for your past salary info and make a slightly better or similar offer....
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[ [], [], [], [], [ "glassdoor.com" ] ]
khs5y
(if there is another way to explain it) why we have silent letters? why is 'doubt' pronounced 'dout'?
explainlikeimfive
http://www.reddit.com/r/explainlikeimfive/comments/khs5y/eli5_if_there_is_another_way_to_explain_it_why_we/
{ "a_id": [ "c2kcfoi", "c2ko583", "c2kcfoi", "c2ko583" ], "score": [ 30, 2, 30, 2 ], "text": [ "A long, long time ago, people spoke differently. They said words in ways that might seem really funny now. They also used lots of other words from other languages, and the way we...
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[ [], [], [], [] ]
3f82y1
Are there photons filling almost every area?
Obviously if i look at something in the distance I see it. And if someone 10m away looks at the same thing, they see it. This can be extrapolated to any distance, you can still see the object. Does this mean that at any time, photons are reflecting from every object at every possible angle in such a way that anyone can...
askscience
http://www.reddit.com/r/askscience/comments/3f82y1/are_there_photons_filling_almost_every_area/
{ "a_id": [ "ctmkz0m" ], "score": [ 6 ], "text": [ "Don't think of light as photons. Think of the electromagnetic field around us as a choppy sea (although 3D instead of a 2D surface). \n\nAnything that has any kind of heat is constantly giving off waves (with wavelengths (= energies) determined b...
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[ [] ]
lx410
Arsenic based micro-organisms?
Can anyone out there shed some light on the "GFAJ-1" bacteria found in the arsenic rich Mono Lake?
askscience
http://www.reddit.com/r/askscience/comments/lx410/arsenic_based_microorganisms/
{ "a_id": [ "c2wab1y", "c2wab1y" ], "score": [ 2, 2 ], "text": [ "These really aren't arsenic-based; instead, As replaces some of the P. Here's a [summary article](_URL_0_).", "These really aren't arsenic-based; instead, As replaces some of the P. Here's a [summary article](_URL_0_)." ...
[]
[]
[ [ "http://www.newscientist.com/blogs/shortsharpscience/2011/05/arsenic-based-bacteria-fact-or.html" ], [ "http://www.newscientist.com/blogs/shortsharpscience/2011/05/arsenic-based-bacteria-fact-or.html" ] ]
88mmls
Why is there layers in the atmosphere is it's all the same gas, like how do they decide where the layer stops and the next starts?
askscience
https://www.reddit.com/r/askscience/comments/88mmls/why_is_there_layers_in_the_atmosphere_is_its_all/
{ "a_id": [ "dwlrbgg", "dwm66ma", "dwma9ko" ], "score": [ 30, 5, 2 ], "text": [ "The layers are based on the air temperature, and the layers differ in how they're heated by the sun.\n\nThe lowermost layer, the troposphere, is heated mainly by sunlight striking the ground. The air ...
[]
[]
[ [], [], [] ]
4yielb
Why was Earth and Mars "seeded" with water and not liquid methane like Titan, and vice-versa?
Basically I'm wondering why water is so abundant on Earth and to some extent Mars, but on Titan, its surface is relatively abundant in methane while water is scarce.
askscience
https://www.reddit.com/r/askscience/comments/4yielb/why_was_earth_and_mars_seeded_with_water_and_not/
{ "a_id": [ "d6oaywr", "d6ogvwl" ], "score": [ 10, 2 ], "text": [ "Well, it's mostly because Titan is cold enough for methane to be a liquid at low pressures, and at those temperatures and pressures water is ice. And on the whole, [Titan is primarily composed of water-ice and rocky materia...
[]
[]
[ [ "https://en.wikipedia.org/wiki/Titan_(moon)" ], [ "https://qph.ec.quoracdn.net/main-qimg-8fc0719a41d3e028b047449608095f75-c?convert_to_webp=true" ] ]
755cka
why do you feel rejuvenated if you take a 15 minute power nap when feeling sleepy during the day, but if you hit the snooze button in the morning, you still feel so sleepy afterwards?
explainlikeimfive
https://www.reddit.com/r/explainlikeimfive/comments/755cka/eli5_why_do_you_feel_rejuvenated_if_you_take_a_15/
{ "a_id": [ "do4path", "do4pv0e" ], "score": [ 6, 3 ], "text": [ "Simply because you enter the state of [REM (Rapid eye movement) sleep](_URL_1_).\n\nWe don't know everything about REM sleep yet and there are a lot of contradictory hypotheses about it. This is the phase in your sleep where...
[]
[]
[ [ "https://en.wikipedia.org/wiki/Echidna", "https://en.wikipedia.org/wiki/Rapid_eye_movement_sleep", "https://en.wikipedia.org/wiki/Oceanic_dolphin" ], [ "https://gdblogs.shu.ac.uk/b2006900/wp-content/uploads/sites/15/2014/10/sleep-cycle1.gif" ] ]
uxzue
Would it be possible for a black hole to approach our solar system undetected?
Could the first sign of it be it's effects on the planet's orbits, or is there no way it could get that close undetected?
askscience
http://www.reddit.com/r/askscience/comments/uxzue/would_it_be_possible_for_a_black_hole_to_approach/
{ "a_id": [ "c4zkd9a", "c4zktov" ], "score": [ 3, 2 ], "text": [ "[I'm not an expert]\n\nI believe we would be able to see a [gravitational lensing effect](_URL_0_), as the black hole's gravity bends light around it, distorting our view of the stars behind it.", "It would depend on the...
[]
[]
[ [ "http://en.wikipedia.org/wiki/Gravitational_lens" ], [] ]
4mapn8
Is it true that the Persian empire had 44% of the world's population living within it?
And what were the methods used to determine population estimates of the ancient world?
AskHistorians
https://www.reddit.com/r/AskHistorians/comments/4mapn8/is_it_true_that_the_persian_empire_had_44_of_the/
{ "a_id": [ "d3u6nw4" ], "score": [ 4 ], "text": [ "The Persian Empire reached its peak during the time of Darius the Great, around 500 BC.\n\nTo get an estimate of what fraction of the world's people lived under the rule of the Achaemenids, you need an estimate of the world population and the pop...
[]
[]
[ [ "https://en.wikipedia.org/wiki/World_population_estimates" ] ]
1n14nr
We know that the universe contains billions of galaxies, but how many are individually catalogued?
askscience
http://www.reddit.com/r/askscience/comments/1n14nr/we_know_that_the_universe_contains_billions_of/
{ "a_id": [ "cceja7a", "ccep2yx" ], "score": [ 3, 3 ], "text": [ "The crowd-sourced [Galaxy Zoo project](_URL_1_) has compiled basic information (position and rough morphological type) for [about 900,000 galaxies](_URL_0_). It's by no means comprehensive, but it's the largest catalog that ...
[]
[]
[ [ "http://arxiv.org/abs/1007.3265", "http://www.galaxyzoo.org/" ], [ "http://www.sdss3.org/dr10/", "http://heasarc.gsfc.nasa.gov/W3Browse/all/milliquas.html" ] ]
49btdk
why are nuclear weapon states modernising their nuclear weaponry when they have already committed to the npt?
explainlikeimfive
https://www.reddit.com/r/explainlikeimfive/comments/49btdk/eli5_why_are_nuclear_weapon_states_modernising/
{ "a_id": [ "d0qkz5q", "d0ql0nb", "d0ql3pm", "d0qnguk" ], "score": [ 2, 8, 2, 2 ], "text": [ "Mostly as a safety measure. To let the world know that, yes we will not use them but if need be we will", "NPT is Non Proliferation - meaning the intention is to prevent the sp...
[]
[]
[ [], [], [], [] ]
cdlcr6
Do stars make sound?
askscience
https://www.reddit.com/r/askscience/comments/cdlcr6/do_stars_make_sound/
{ "a_id": [ "etvrdxz", "ety0rr3", "eu0f4z7" ], "score": [ 20, 3, 2 ], "text": [ "\"sound\" is just a vibration. It needs something to be propagated, like air.\nIn space, there isn't anything to propagate that vibration, so you don't hear a thing.\nIf you were to somehow put a star ...
[]
[]
[ [], [], [] ]
1h332x
What can be said for "building up immunity" by being exposed to germs and bacteria?
askscience
http://www.reddit.com/r/askscience/comments/1h332x/what_can_be_said_for_building_up_immunity_by/
{ "a_id": [ "caqh21e" ], "score": [ 3 ], "text": [ "Yup, to some extent. I posted this before, but I think it's relevant to your question.\n\nFirst, we need to clarify what a strong immune system is. Very simply put, the immune system is a set of cells and proteins that react to foreign bodies and...
[]
[]
[ [ "http://www.cellsalive.com/pics/nbt.gif" ] ]
1jzc4d
Why are there not more Spaniards in the United States?
I'm making a couple of assumptions here..first, that my impression that there *aren't* a lot of Spanish-Americans in the U.S. and second, that there is a historical reason for this. So, forgive me if neither of these are the case. Anyhow, it does seem like there are plenty of immigrants from just about every other par...
AskHistorians
http://www.reddit.com/r/AskHistorians/comments/1jzc4d/why_are_there_not_more_spaniards_in_the_united/
{ "a_id": [ "cbjt4bt", "cbju4aw" ], "score": [ 2, 14 ], "text": [ "As of 2000 there were about 83,000 people living in America who were born in Spain. That's about the same as the Czech Republic.\n\nBut I get the sense that you're asking about \"people of Spanish heritage\". Is that a go...
[]
[]
[ [], [] ]
rhs43
Does an atom have a color?
Hello r/askscience. So I was just thinking about how everything in this world has a color, and that everything is made up of atoms. So my question to you: Does atoms have colors(or colours if you prefer), to show a given thing the color they show up as?
askscience
http://www.reddit.com/r/askscience/comments/rhs43/does_an_atom_have_a_color/
{ "a_id": [ "c45y7rn", "c45y8qb", "c45yif4", "c4653nt", "c466gfn", "c46a9uj" ], "score": [ 42, 4, 8, 2, 9, 2 ], "text": [ "Sort of, and only with some explanation.\n\nFor example, certain atoms, when energized in various ways, emit photons of specific wavele...
[]
[]
[ [ "http://en.wikipedia.org/wiki/H-alpha", "http://swrl.njit.edu/ghn_web/" ], [], [ "http://www.aps.org/meetings/march/vpr/2011/imagegallery/bariumions.cfm", "http://www.phys.washington.edu/users/deepg/research.shtml" ], [], [ "http://en.wikipedia.org/wiki/Rayleigh_scattering", "h...
7eggtl
How fast does a pressurized gas move to a lower pressure area?
I remember being told that the pressure wave velocity is limited to the speed of sound in that medium at whatever temperature it is at. So if you had two tanks (A and B) joined by a pipe with a valve, tank A is pressurized and tank B is at atmospheric pressure. The valve is then instantly opened. Is the velocity of t...
askscience
https://www.reddit.com/r/askscience/comments/7eggtl/how_fast_does_a_pressurized_gas_move_to_a_lower/
{ "a_id": [ "dq4xq0x", "dq4z79q", "dq50l7d" ], "score": [ 20, 5, 10 ], "text": [ "The velocity of a pressure *wave* is not the velocity of the medium itself, but rather the velocity of the change in pressure *relative to* the medium. The medium itself can have any velocity, like th...
[]
[]
[ [], [ "https://en.m.wikipedia.org/wiki/Choked_flow?wprov=sfla1" ], [] ]
1cwggf
Political influences on the work of historians
Throughout the 20. century, current political events have shaped the view on the past. How yesterday is viewed has often implications on the politics of today. Does this same effect still influence the work of professional historians in western democracies today?
AskHistorians
http://www.reddit.com/r/AskHistorians/comments/1cwggf/political_influences_on_the_work_of_historians/
{ "a_id": [ "c9lrexi" ], "score": [ 2 ], "text": [ "Absolutely it does. How has no one answered this question?\n\nThere are almost too many examples to choose from, but in the 1960s social historians made its real debut with much of the leftist protest groups, the non-elites writing history as a r...
[]
[]
[ [] ]
1asqor
Some events (quantum scale) are known to be truly random, not deterministic. How do we infer that they are really random?
How do we "know" (Everything is best guess.) that these events that we call "random" are not e.g. a deterministic result of the total sum of all events in the universe, like water flowing down a drain? Are we not just drops looking at our neighbor-drop, unable to infer why it is behaving like that? Or is the choice of...
askscience
http://www.reddit.com/r/askscience/comments/1asqor/some_events_quantum_scale_are_known_to_be_truly/
{ "a_id": [ "c90eb5a", "c90eqle", "c90f61i", "c90fea4", "c90ij2c", "c90nknp", "c90r1tp", "c90rln0" ], "score": [ 10, 6, 7, 58, 2, 7, 3, 2 ], "text": [ "The mathematical basis of quantum theory, which has been supported many times by countless...
[]
[]
[ [], [ "http://arxiv.org/abs/1004.1521" ], [ "http://lin25.thphys.uni-heidelberg.de/~wetzel/qm2005/protected/hidden_var_mermin.pdf" ], [], [], [], [], [] ]
fde33t
Early Punk and especially Hardcore Punk appear quite dominated by male bands and fans. But what roles did women and/or LGBTQ+ people play in those scenes?
With early Punk I could think at least of some very influential women: from designer Vivienne Westwood to musicians like Patti Smith or X-Ray Spex. But my impression is that into the 80s and with the beginning of Hardcore, there seems to be less influence from LGBTQ+ people and women. Ie this very representative photo ...
AskHistorians
https://www.reddit.com/r/AskHistorians/comments/fde33t/early_punk_and_especially_hardcore_punk_appear/
{ "a_id": [ "fjh6r9a" ], "score": [ 35 ], "text": [ "Hi there, modern historian of political culture & national identity and lifelong punkrock fan here! I love this question, and I'm going to answer it to the best of my abilities, which are, admittedly somewhat limited. The overall disclaimer i...
[]
[ "https://i.pinimg.com/originals/f5/13/dd/f513dd544efd2455e4c91293cbf71546.jpg" ]
[ [] ]
2i2ejs
What colour is the sky on Phobos? Why?
Would it change colour and how often?
askscience
http://www.reddit.com/r/askscience/comments/2i2ejs/what_colour_is_the_sky_on_phobos_why/
{ "a_id": [ "cky6nsl", "cky7oa9", "ckylp6b" ], "score": [ 8, 3, 2 ], "text": [ "The color of the sky on Phobos is black, because Phobos is very small and can't retain an atmosphere. The reason our sky is blue is because there are molecules in our atmosphere that scatter blue light ...
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[]
[ [], [], [] ]
5uv390
how did having light breakfasts and heavy dinners become a common practice, when logically it should be reversed?
explainlikeimfive
https://www.reddit.com/r/explainlikeimfive/comments/5uv390/eli5_how_did_having_light_breakfasts_and_heavy/
{ "a_id": [ "ddx2an1", "ddx2fye", "ddx6dfo", "ddx7kov", "ddxct21", "ddxgbfy", "ddxn0bx", "ddxnwf2" ], "score": [ 47, 12, 8, 7, 3, 5, 3, 2 ], "text": [ "I can't explain breakfast not being the biggest meal but this may help.\n\nIn short, as ma...
[]
[]
[ [], [], [], [], [], [], [], [] ]
cupsqe
how does wind passing over an opening make noise? (i.e; whistling or a howling wind)
explainlikeimfive
https://www.reddit.com/r/explainlikeimfive/comments/cupsqe/eli5_how_does_wind_passing_over_an_opening_make/
{ "a_id": [ "exx8loq" ], "score": [ 22 ], "text": [ "Noise or sound is basically just pressure waves in the air, which causes the air molecules to squish and stretch really fast at certain *frequencies* or pitches. \nYou know how when you rub a wet finger around a wine glass it makes a sound? That...
[]
[]
[ [] ]
2ocqkd
When a spring is overstretched, where does the potential energy go?
Hi, when a spring is stretched, I understand that the kinetic energy is transformed into elastic potential energy. But when the spring is stretched too much and won't spring back, where does the energy go?
askscience
http://www.reddit.com/r/askscience/comments/2ocqkd/when_a_spring_is_overstretched_where_does_the/
{ "a_id": [ "cmlzumh" ], "score": [ 20 ], "text": [ "Into \"plastic deformation\": \n_URL_0_ \nwhich is pretty much rearranging the material/metal." ] }
[]
[]
[ [ "https://en.wikipedia.org/wiki/Deformation_%28engineering%29#Plastic_deformation" ] ]
206tgg
What does an increase in the fuel efficiency of cars do in the supply and demand model?
Looking at the market for gasoline, would you shift the demand curve to the left because less fuel will be demanded, or would there be a rebound effect increasing the demand for fuel? If yes, how would this be shown in the model?
askscience
http://www.reddit.com/r/askscience/comments/206tgg/what_does_an_increase_in_the_fuel_efficiency_of/
{ "a_id": [ "cg1sja4", "cg1zk1f" ], "score": [ 2, 2 ], "text": [ "You would expect demand to shift left, yes. Less fuel should be demanded if you use less of it to travel the same distance.\n\nIn response to the lower demand, supply might also end up shifting to counter this in an attempt ...
[]
[]
[ [], [ "http://www.culturechange.org/issue8/fuel%20economy%20standards.htm", "http://www.google.com/url?sa=t&rct=j&q=&esrc=s&source=web&cd=7&ved=0CHQQFjAG&url=http%3A%2F%2Fwww.uh.edu%2F~cmurray%2FTCE15%2FPapers%2FLiu.pdf&ei=HjMiU_7WHoqTyQHrwICYCA&usg=AFQjCNFhq3Nss1r_IYYy...
17own3
will food rot/expire in outer space?
i am just wondering will food rot in space.
askscience
http://www.reddit.com/r/askscience/comments/17own3/will_food_rotexpire_in_outer_space/
{ "a_id": [ "c87hctz", "c87nitz", "c87ppoa", "c87v05a", "c87vx7s", "c87z8b0" ], "score": [ 404, 22, 20, 2, 7, 2 ], "text": [ "Yes it can do, it depends on the circumstances. Ordinary untreated food would rot if it was in a spaceship. 'Space food' eaten by as...
[]
[]
[ [], [], [ "http://www.youtube.com/watch?v=0l5VToaoUdY" ], [], [], [ "http://youtu.be/GGmaXX59aq8?t=26m10s" ] ]
1i06lo
How effective was medieval plate mail at protecting the user?
After watching too much Game of Thrones, I wondered how effective plate mail was in medieval times? Could a knight attack unarmored opponents without worrying much about killed? Was it more for show? I know there are probably different types and qualities, but I'm too ignorant to narrow my question anymore.
AskHistorians
http://www.reddit.com/r/AskHistorians/comments/1i06lo/how_effective_was_medieval_plate_mail_at/
{ "a_id": [ "cazpuwh", "cazqhqd", "cb0bs98" ], "score": [ 8, 22, 4 ], "text": [ "Since you are basing your question on Game of Thrones, I was wondering if you could specify which armor and/or character you were referring too? From my memory almost nobody actually wears true plate a...
[]
[]
[ [ "http://images5.fanpop.com/image/photos/29300000/Sandor-Clegane-house-lannister-29389181-1600-1065.jpg", "http://images2.wikia.nocookie.net/__cb20110623091538/gameofthrones/images/6/67/Lorasknight.png" ], [ "http://en.wikipedia.org/wiki/Estoc", "http://en.wikipedia.org/wiki/Halberd" ], [ ...
5vnos5
how do frogs just suddenly appear in areas that experience heavy rain where there wasn't any water before?
I'm from California, and we've obviously been in a drought lately. After the heavy rainstorms, I've been walking to a park near my house when the sun sets, and the croaking of what sounds like hundreds and hundreds of frogs can be heard all throughout the park. There are no bodies of water in the park, so how can the f...
explainlikeimfive
https://www.reddit.com/r/explainlikeimfive/comments/5vnos5/eli5_how_do_frogs_just_suddenly_appear_in_areas/
{ "a_id": [ "de3ocnp", "de3okku" ], "score": [ 27, 312 ], "text": [ "While there are possible explanations such as meteorological events like waterspouts that could cause it to \"rain frogs\", the more likely answer is these frogs are actually toads.\n\nToads typically don't live near bodi...
[]
[]
[ [], [] ]
1462fq
How did suicide bombings become an accepted weapon of resistance?
I guess I could understand attacking military targets, but what made groups think it would be appropriate to blow themselves up in a crowded market? Why do suicide bombings seem to be so popular with mostly Islamic groups and the Tamil Tigers? Have other groups (IRA, ETA, FARC, etc.) used suicide bombers? Does religio...
AskHistorians
http://www.reddit.com/r/AskHistorians/comments/1462fq/how_did_suicide_bombings_become_an_accepted/
{ "a_id": [ "c7a95qc", "c7apkgj", "c7awj4n" ], "score": [ 7, 3, 2 ], "text": [ "These are a lot of questions, and I can't answer all of them, but I can give my perspective.\nThe idea of a fire ship, that is to ram an enemy ship with a burning ship of your own, seems to be pretty ol...
[]
[]
[ [], [], [] ]
11k4e1
how to convert black and white photos to colour
How does it work? Do the black and white shades have coloured counter parts?
explainlikeimfive
http://www.reddit.com/r/explainlikeimfive/comments/11k4e1/eli5_how_to_convert_black_and_white_photos_to/
{ "a_id": [ "c6n6w2n", "c6n7i9f" ], "score": [ 7, 10 ], "text": [ "Sometimes you can understand what color it is via the shade of gray. But most of the time you need to make educated guesses. A lot of it is a guessing game, and playing with the hues and saturation and stuff.", "You col...
[]
[]
[ [], [] ]
7ize2h
They say that prostitution is the oldest occupation, so what is the oldest known record of a prostitute? What does the record say? Do we know anything about their life at that time?
AskHistorians
https://www.reddit.com/r/AskHistorians/comments/7ize2h/they_say_that_prostitution_is_the_oldest/
{ "a_id": [ "dr2qhds", "dr3ow21", "dr3wt6t" ], "score": [ 56, 23, 26 ], "text": [ "Related: in the oldest record do we know what goods were exchanged for services rendered?", "Prostitution appears in the bible in the book. If Genesis. Judah pays a prostitute (his daughter-in-la...
[]
[]
[ [], [], [] ]
5fo2np
Why are there so few viking-era helmets compared to iron-bossed shields?
Viking shields are typically shown to have an iron bosse in the center attached with clinched nails (suggested here - _URL_0_) or alternatively (what I conjecture) rivets. It protects the hand of the user. Some of them could have semi-elaborate shapes, and it suggests to me that the norse knew how to forge them on th...
AskHistorians
https://www.reddit.com/r/AskHistorians/comments/5fo2np/why_are_there_so_few_vikingera_helmets_compared/
{ "a_id": [ "dalsd0x" ], "score": [ 3 ], "text": [ "Okay, it's late, I'm tired, and I've been into my cup a bit, but I will try to explain.\n\nFor one thing, from your own Hurstwic, the typical Viking-era shield was chamfered from about 1/2\" towards the center to 1/4\" at the edges. This means t...
[]
[ "http://www.hurstwic.org/history/articles/manufacturing/text/viking_shields.htm" ]
[ [] ]
1bwhej
how do flaming arrows do anything to attackers that regular arrows don't?
I feel like flaming arrows are in every battle scene, used to hit charging warriors. I can see how they'd be used against ships, walls, structures, etc, but what the hell do they do extra to flesh? burn their guts?
explainlikeimfive
http://www.reddit.com/r/explainlikeimfive/comments/1bwhej/eli5_how_do_flaming_arrows_do_anything_to/
{ "a_id": [ "c9aqabb", "c9aqvgp" ], "score": [ 3, 2 ], "text": [ "Movies like to exaggerate for effect. Flaming arrows look cool so people use them. I'm aware of no instance in the historical record where they were used deliberately against people.", "I doubt they were ever used in rea...
[]
[]
[ [], [] ]
urr6i
what was the impact of the patriot act on civil rights?
Revising for my politics exam on monday, I often reference the patriot act as an example of civil rights and liberties being suspended but am unsure as to what specifically it suspended
explainlikeimfive
http://www.reddit.com/r/explainlikeimfive/comments/urr6i/eli5_what_was_the_impact_of_the_patriot_act_on/
{ "a_id": [ "c4xxuow" ], "score": [ 3 ], "text": [ "google it to get more specific examples, but it essentially gives the Govt the ability to more closely monitor certain individuals or transactions that may previously have been protected by confidentiality laws or 4th amend and related laws. " ...
[]
[]
[ [] ]
3c0e0e
Was frederick the great gay?
Ive Read that freddy the great was called a sodomite by his father In his younger days and that he apparently had male lovers. Is this true or just fabricated by his enemies? As a side question, how did he get "the Great" title? He was not a particularly good general like his brother. Did he realy deserve it?
AskHistorians
http://www.reddit.com/r/AskHistorians/comments/3c0e0e/was_frederick_the_great_gay/
{ "a_id": [ "csr85xk" ], "score": [ 46 ], "text": [ "He was most likely not homosexual. The claims of him being homosexual originate from a opinion piece published in London under a fake name which claimed that Frederick's court was a bastion of immorality with young male sex slaves being passed a...
[]
[]
[ [ "http://www.zum.de/whkmla/histatlas/germany/prfrederick.gif" ] ]
1232c4
What are the greatest unsolved mysteries of the Universe?
askscience
http://www.reddit.com/r/askscience/comments/1232c4/what_are_the_greatest_unsolved_mysteries_of_the/
{ "a_id": [ "c6rqdw9" ], "score": [ 2 ], "text": [ "For me the three big ones are\n\n1. Why does the universe exist the way it does.\n\n2. How did the first self replicating cell arise.\n\n3. How does consciousness emerge from physical and chemical reactions in the brain.\n\nThere are lots of list...
[]
[]
[ [ "http://en.wikipedia.org/wiki/List_of_unsolved_problems_in_physics" ] ]
24iwbs
this picture (circuit diagram) about how keyboards work.
_URL_0_
explainlikeimfive
http://www.reddit.com/r/explainlikeimfive/comments/24iwbs/eli5_this_picture_circuit_diagram_about_how/
{ "a_id": [ "ch7knde", "ch7l4kj" ], "score": [ 2, 3 ], "text": [ "The switches (S) represent the keys, and the rows and columns refer to the rows and columns of the keyboard. Each switch localizes to a unique coordinate on the keyboard. When you depress the key, it closes the circuit bet...
[]
[ "http://upload.wikimedia.org/wikipedia/commons/f/f2/FunctionalCircuitDiagramOfKeyboardNumPadScanningProcedure-small.gif" ]
[ [], [] ]
10tlix
where is the deepest man made hole in the world? and how deep it is?
askscience
http://www.reddit.com/r/askscience/comments/10tlix/where_is_the_deepest_man_made_hole_in_the_world/
{ "a_id": [ "c6gibk3" ], "score": [ 7 ], "text": [ "The Sakhalin-I Z-44 Well in Russia is the deepest hole we've drilled, it's 40,604 feet deep. To give you a sense of scale, that is 0.19% of the way to the center of the Earth. " ] }
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[]
[ [] ]
9h7325
If a object is thousands of light years away from earth, how are we estimating the size and distance?
askscience
https://www.reddit.com/r/askscience/comments/9h7325/if_a_object_is_thousands_of_light_years_away_from/
{ "a_id": [ "e6a0vng" ], "score": [ 16 ], "text": [ "Measuring distances is hard! Until the past couple of years when the GAIA mission started returning data, we were only able to directly measure distances out to a few hundred light years by watching nearby objects move against the background as ...
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2nweef
how is it impossible to counterfeit digital money (or bitcoins)? if it isn't impossible, why hasn't it been done before?
Couldn't a skilled hacker or corrupt bank teller have a transfer of $1 million from Bank 'X', which is a fabricated bank which only exists on paper? It just seems mind boggling to me that there's so much digital currency being moved all around the world, and that no one has figured out a way to make a computer artifici...
explainlikeimfive
http://www.reddit.com/r/explainlikeimfive/comments/2nweef/eli5_how_is_it_impossible_to_counterfeit_digital/
{ "a_id": [ "cmhiy9b" ], "score": [ 10 ], "text": [ "No. That's the beauty of Bitcoin (and [Cryptocurrencies in general](_URL_0_)).\n\nAt the heart of this type of currency is the blockchain, which is just a list of transactions that anyone can view--you can take a look at this page to see an exam...
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[ [ "http://en.wikipedia.org/wiki/Cryptocurrency" ] ]
36wnzi
Would the Japanese have been able to take over part of Mainland America in WWII?
AskHistorians
http://www.reddit.com/r/AskHistorians/comments/36wnzi/would_the_japanese_have_been_able_to_take_over/
{ "a_id": [ "crhsnpd" ], "score": [ 3 ], "text": [ "It wouldn't have been feasible. It's telling that the Japanese high command didn't plan a follow-up to Pearl Harbor and as far as I'm aware never discussed the possibility of hitting it with a ground invasion. At the time the bulk of Japan's war ...
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[ [] ]
1mbdrj
why do republicans desperately want to repeal obamacare?
With as little slant as possible, please
explainlikeimfive
http://www.reddit.com/r/explainlikeimfive/comments/1mbdrj/eli5_why_do_republicans_desperately_want_to/
{ "a_id": [ "cc7kfri", "cc7kl7g", "cc7kww6", "cc7letc", "cc7m5gr" ], "score": [ 2, 2, 4, 5, 7 ], "text": [ "Republican voters don't like President Obama and don't trust that Obamacare is a good thing. Republican politicians want to be re-elected so they try to repe...
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[]
[ [], [], [], [ "http://cdn.front.moveon.org/wp-content/uploads/2012/05/spoton500.jpg" ], [] ]
2weqma
why are nearly all popular fantasy worlds (westeros, middle earth, narnia f.e.) in the middle age?
explainlikeimfive
http://www.reddit.com/r/explainlikeimfive/comments/2weqma/eli5_why_are_nearly_all_popular_fantasy_worlds/
{ "a_id": [ "coq5kb2", "coq5oif", "coq6who", "coq7ml9" ], "score": [ 12, 7, 5, 4 ], "text": [ "Because of the romantic nature of the age of chivalry. We idealize the era and the stories and the mythical aspects of the traditional stories of the time. \n\ntl;dr it was a cool...
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[ [], [], [], [] ]
77ki0k
how the sun "bleach" the color out of things? why does it effect some things (like signs) and not others (like cars)?
explainlikeimfive
https://www.reddit.com/r/explainlikeimfive/comments/77ki0k/eli5_how_the_sun_bleach_the_color_out_of_things/
{ "a_id": [ "domlbjg", "domstbk" ], "score": [ 9, 3 ], "text": [ "It *does* affect cars. It just takes longer. \nThe radiation from the sun gradually breaks down the chemicals that make “color”. The time varies depending on the particular surface/chemical being affected.", "It's mostly...
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[ [], [] ]
a929zu
How does speed affect time in our galaxy that is flying through space and spinning around a SMBH?
From my understanding the faster you travel the slow time "tics" for you. Does that mean that time depends on how fast your host galaxy is traveling through the universe?
askscience
https://www.reddit.com/r/askscience/comments/a929zu/how_does_speed_affect_time_in_our_galaxy_that_is/
{ "a_id": [ "ecgkel6", "ecglw8b" ], "score": [ 9, 8 ], "text": [ "So, the first big thing is there is no such thing as absolute motion. There is no \"centre\" to the Big Bang that we can measure speed against. All galaxies are moving relative to each other, and we can only measure speed in...
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[ [], [] ]
dups6d
how do predators like lions and tigers become pets for humans? how come they don't just kill the humans?
explainlikeimfive
https://www.reddit.com/r/explainlikeimfive/comments/dups6d/eli5_how_do_predators_like_lions_and_tigers/
{ "a_id": [ "f77lgn2", "f77lji9", "f77nf9y" ], "score": [ 5, 48, 10 ], "text": [ "After thousands of years, the common house cat became domesticated. Tigers and lions are not meant to be pets for humans, and given the opportunity, could potentially harm a human. You see videos of t...
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[]
[ [], [], [] ]
2tkm6p
what determines which cables have ferrite beads and which don't
[Ferrite Beads](_URL_0_)
explainlikeimfive
http://www.reddit.com/r/explainlikeimfive/comments/2tkm6p/eli5what_determines_which_cables_have_ferrite/
{ "a_id": [ "cnzvdhk", "cnzvdjm" ], "score": [ 3, 5 ], "text": [ "Ferrite beads are used to help control induced high frequency noise. If there are other inductors elsewhere in the circuit, it may not be needed.", "The purpose of ferrite beads on cables is to suppress high frequencies ...
[]
[ "https://www.google.ca/search?q=ferrite+beads&safe=off&client=safari&rls=en&source=lnms&tbm=isch&sa=X&ei=rkXEVO_yH8yzggTZtYCwAQ&ved=0CAgQ_AUoAQ&biw=1155&bih=894" ]
[ [], [] ]
3dhlqu
did those duracell batteries with the little "press here to see power remaining" function actually work? if so, how?
[Link](_URL_0_) for those who need visual context. They were Duracell batteries with the little white circles. I remember, as a kid, trying to press super hard on them but nothing ever changed on the little strip. Did it actually work, and if it did, how would it show it and what did me pressing have to do with it?
explainlikeimfive
http://www.reddit.com/r/explainlikeimfive/comments/3dhlqu/eli5_did_those_duracell_batteries_with_the_little/
{ "a_id": [ "ct57dni" ], "score": [ 7 ], "text": [ "They did. \n\nYou'd have to press really hard though, and then the line would fill up/ turn transparent indicating how full the battery was.\n\nAccording to an older ELI5 threat, pressing on the circle's would close a circuit within the battery, ...
[]
[ "http://ecx.images-amazon.com/images/I/91JWFjrg6lL._SL1500_.jpg" ]
[ [ "https://www.reddit.com/r/explainlikeimfive/comments/11h5ev/how_does_duracell_powercheck_work/" ] ]
8sirzw
why does the water behind a boat or other watercraft become lighter in colour?
I always see boats, jet skis and other craft on the water and as the move along the trailing water becomes lighter and sometimes clearer. Why is this?
explainlikeimfive
https://www.reddit.com/r/explainlikeimfive/comments/8sirzw/eli5_why_does_the_water_behind_a_boat_or_other/
{ "a_id": [ "e0zqnmg" ], "score": [ 12 ], "text": [ "Air bubbles. When the water is churned up like that, air gets mixed in, making it appear lighter in color." ] }
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[ [] ]
89wce2
How important was Allied Lend-Lease to the USSR during WW2? Approximately how much of the gear in use by the Red Army was supplied by the other allied powers?
AskHistorians
https://www.reddit.com/r/AskHistorians/comments/89wce2/how_important_was_allied_lendlease_to_the_ussr/
{ "a_id": [ "dwu2yxn" ], "score": [ 3 ], "text": [ "There's more to be said on the topic; you might like to start with some previous answers in the FAQ section Economy, Industry, and Lend-Lease.\n\n* \"In WW2, who had greater industrial capacity, the Americans or the Soviets?\", _URL_3_ , by /u/Ge...
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[ [ "https://www.reddit.com/r/AskHistorians/wiki/faq/militaryhistory/wwii/ussr#wiki_economy.2C_industry.2C_and_lend-lease", "https://www.reddit.com/r/AskHistorians/comments/3pa76y/i_often_hear_people_say_that_the_united_states/cw4yywc?context=3", "https://www.reddit.com/r/AskHistorians/comments/3mnhr2/sov...
4zk9uq
how do manufacturers imprint the letter on m & ms, smarties etc?
explainlikeimfive
https://www.reddit.com/r/explainlikeimfive/comments/4zk9uq/eli5_how_do_manufacturers_imprint_the_letter_on/
{ "a_id": [ "d6whipc" ], "score": [ 2 ], "text": [ "They use a process called \"Offset printing\". First, you get a metal plate made with the imprint of the design you want, let's say the famous m on M & M's, which is then transferred onto a rubber cylinder (called a blanket). This acts an interme...
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a05ln0
I recently learned that white southerners could take out a "mortgage" to purchase a slave on credit. How did emancipation affect these lines of credit? Is there any link between these creditors and Jim Crow practices that entrapped former slaves in indentured servitude?
Also, how exactly did the process of taking out a loan for a slave work? How much assets did the aspiring slave master need?
AskHistorians
https://www.reddit.com/r/AskHistorians/comments/a05ln0/i_recently_learned_that_white_southerners_could/
{ "a_id": [ "eaf4zzr" ], "score": [ 4 ], "text": [ "Followup question -- was there any securitisation of slave mortgages? In other words, are there records of sharing a slave with my neighbours based on how much we contributed to their purchase price?" ] }
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[ [] ]
28h3xn
What started the tradition of brewing and winemaking in some European monasteries?
I'd recently read Joh Araki's manga *Bartender*, and every chapter always goes into detail about the origins and uses of various liquors. One variety that often pops up are alcohol traditionally made in monasteries. This struck me as a little odd - I'm not a religious person and I know little about Christianity, but I ...
AskHistorians
http://www.reddit.com/r/AskHistorians/comments/28h3xn/what_started_the_tradition_of_brewing_and/
{ "a_id": [ "ciawlw3" ], "score": [ 5 ], "text": [ "A caveat before I answer this: I didn't get much sleep last night and don't feel very coherent today so I apologize in advance if this is poorly written.\n\n > I was always under the impression that drunkenness had always been considered sinful,...
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[ [] ]
11dxi0
What is the heaviest thing in the universe per cm sq?
Title says it all, just curious if people actually know. edit: PER cubic cm (;
askscience
http://www.reddit.com/r/askscience/comments/11dxi0/what_is_the_heaviest_thing_in_the_universe_per_cm/
{ "a_id": [ "c6llrtn", "c6lm0fl", "c6lokbz", "c6lorxk" ], "score": [ 14, 13, 2, 9 ], "text": [ "If you exclude black holes, some of the densest objects in the universe are Neutron Stars. [Wikipedia](_URL_0_) describes their density: \n > Neutron stars contain 500,000 times...
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[]
[ [ "http://en.wikipedia.org/wiki/Neutron_star" ], [], [ "http://en.wikipedia.org/wiki/Black_hole#Singularity" ], [ "http://arxiv.org/abs/gr-qc/9310026", "http://en.wikipedia.org/wiki/Holographic_principle" ] ]
6cr1td
what is the medical cause of that awful sour alcoholic body smell? i don't mean that boozy smell off someone who did a one-night binge, i mean that horrific chemical deathly aroma that radiates off the stranger in the public place, who you instantly know is an alcoholic from ten feet away.
Just got off jury duty and there was a guy like this in the group of potential jurors. I've encountered this in various public places, from young(ish) adults to older folks. What is physically going on with that distinct odor?
explainlikeimfive
https://www.reddit.com/r/explainlikeimfive/comments/6cr1td/eli5_what_is_the_medical_cause_of_that_awful_sour/
{ "a_id": [ "dhwsmc7" ], "score": [ 3 ], "text": [ "What she is smelling is not just ethanol. Pure ethanol has little smell. If you were on jury duty it is safe to assume that he was not drinking the process so what you were smelling the body's breakdown products of alcohol. Acetaldehyde is prod...
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vf4hz
Is it safe to drink boiling water from a plastic (PET) soda bottle?
Is there any danger of chemicals leaching into the water if I put hot tea into a plastic pop bottle (and cool it to make iced tea)? Edit: I know studies found leakage of BPA from heated polycarbonate bottles, but that is a different kind of plastic, and I can't find any results for PET.
askscience
http://www.reddit.com/r/askscience/comments/vf4hz/is_it_safe_to_drink_boiling_water_from_a_plastic/
{ "a_id": [ "c53y2mu" ], "score": [ 11 ], "text": [ "Its never safe to drink 'boiling' water. You will injure yourself." ] }
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[ [] ]
9wwn8i
why dont bones melt?
explainlikeimfive
https://www.reddit.com/r/explainlikeimfive/comments/9wwn8i/eli5_why_dont_bones_melt/
{ "a_id": [ "e9nv3ko", "e9nvq2d" ], "score": [ 7, 2 ], "text": [ "Bones, like many other things, have a really high melting temperature... The problem is that the temperature required to overcome the oxidation activation energy is well below the melting point meaning if you were to try to ...
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[ [], [] ]
17j49q
what these math gifs are actually representing
I found this post [(link)](_URL_0_) on /r/funmath and found myself thinking, 'These are really cool. I wish I knew what they actually meant.' Please can someone ELI5 what is being shown in any of them? _URL_0_
explainlikeimfive
http://www.reddit.com/r/explainlikeimfive/comments/17j49q/eli5_what_these_math_gifs_are_actually/
{ "a_id": [ "c85ysiy", "c85z5ie" ], "score": [ 2, 2 ], "text": [ "I think you're going to have to chose just one at a time if you want to be explained to like you're 5. Which one's the most intriguing for you, and I'll give it a shot. ", "A lot of those diagrams are visual representati...
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[ "http://www.reddit.com/r/funmath/comments/16vteq/gif_beauty_of_math_should_always_be_taught_first/" ]
[ [], [] ]
1gvsiy
What is the oldest "counterculture" movement we know of?
I'm talking about something like the flappers of the early 20th century and the hippies of the late. Thank you!
AskHistorians
http://www.reddit.com/r/AskHistorians/comments/1gvsiy/what_is_the_oldest_counterculture_movement_we/
{ "a_id": [ "caocdg3", "caocivq", "caocn9v", "caocr7q", "caoct2h", "caoe2is", "caofuy5", "caogz05", "caomnhw" ], "score": [ 30, 7, 22, 13, 358, 14, 7, 4, 3 ], "text": [ "Probably not the earliest but ancient Roman youths at various ti...
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[ [ "http://www.dancarlin.com/disp.php/hharchive/Show-34---Death-Throes-of-the-Republic-I/" ], [], [], [], [], [], [ "http://www.biblegateway.com/passage/?search=1%20Kings%2012:1-15,2%20Chronicles%2010:1-15&version=NASB" ], [ "http://en.wikipedia.org/wiki/Buddhism#History" ], [ ...
6uu5m6
Was splitting the Roman empire Into two a distinct reason for the fall of Rome?
AskHistorians
https://www.reddit.com/r/AskHistorians/comments/6uu5m6/was_splitting_the_roman_empire_into_two_a/
{ "a_id": [ "dlvklux" ], "score": [ 14 ], "text": [ "Short answer is no.\n\nThe reasons behind the splitting of the empire made complete sense at the time. Basically the progression of the idea was this. The empire was too large for one man to rule effectively so it became clear that delegation wa...
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26hju4
Do animals that use tools ever display some thought of "This tool *in particular* is the best of its kind" and keep them, or do they generally always just make a new one every time they need one?
Like crows or primates that probe holes with sticks, for example. If they got a stick that was particularly well-suited for the task, do they recognize the difference and hold onto it for future use? If so, what does this say about their intelligence?
askscience
http://www.reddit.com/r/askscience/comments/26hju4/do_animals_that_use_tools_ever_display_some/
{ "a_id": [ "chrh07z" ], "score": [ 82 ], "text": [ "Yes they do! Chimpanzees use different tools in different contexts and manufacture their own tools. They'll also use multiple tools in different sequences, and they show others how to use them ([source](_URL_1_) - paywall). Bonobos and orangutan...
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[]
[ [ "http://www.eva.mpg.de/psycho/pdf/Mulcahy&Call2006SCI.pdf", "http://m.sciencemag.org/content/328/5978/579.summary", "http://rsbl.royalsocietypublishing.org/content/early/2011/09/06/rsbl.2011.0782.full.html", "http://rspb.royalsocietypublishing.org/content/271/Suppl_3/S88.abstract", "http:/...
f9byx
Interesting video projector effect (can see RGB colours when moving my eyes)
Today I was sitting in class and one of our video projectors was showing a white screen. I could see the reflection of light coming out of the projector on the wall. It looked like a big white dot (the size of projector's lens obviously). Every time I moved my eyes around or blinked there would appear 3 red, green and ...
askscience
http://www.reddit.com/r/askscience/comments/f9byx/interesting_video_projector_effect_can_see_rgb/
{ "a_id": [ "c1e9jun", "c1e9kkj", "c1e9l7z", "c1e9ln8" ], "score": [ 2, 3, 21, 9 ], "text": [ "Is it the same thing that happens with the light on a flat bed scanner? I know that always breaks up into RGB when I look around", "Depends on how the projector was working. ...
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[ [], [], [ "http://en.wikipedia.org/wiki/Digital_Light_Processing#The_color_wheel_.22rainbow_effect.22" ], [ "http://en.wikipedia.org/wiki/Digital_Light_Processing#Cons" ] ]
129bdv
A question about the measuring of gravity.
I have been bouncing this around in my head for a while, so it is time to just ask. My question is how the force of gravity for other planets or stars is measured. The basic bit I remember for High School Science class is that mass is the key factor, the larger the mass, the greater the force of gravity. I was think...
askscience
http://www.reddit.com/r/askscience/comments/129bdv/a_question_about_the_measuring_of_gravity/
{ "a_id": [ "c6t7ugw" ], "score": [ 2 ], "text": [ "There is, Newton's Law of Gravity. " ] }
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[ [] ]
1004lc
Why do Americans no longer drink at work?
Mad Men shows executives enjoying several drinks during the workday, and as I understand it, this was fairly common in the 60s. When and why did it become "inappropriate" to drink during the workday? It's not like America wasn't productive 40 years ago.
AskHistorians
http://www.reddit.com/r/AskHistorians/comments/1004lc/why_do_americans_no_longer_drink_at_work/
{ "a_id": [ "c698zpb", "c69aoq6", "c69d7ts", "c69es9e", "c69etd2", "c69exkb" ], "score": [ 14, 55, 6, 2, 3, 4 ], "text": [ "You should check out this book: _URL_0_\n\nBut a lot of it has to do with the association with alcoholism and the more prevalent natur...
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[ [ "http://www.cornellpress.cornell.edu/book/?GCOI=80140100221840&fa=author&person_id=2653" ], [], [], [ "http://abcnews.go.com/Business/drinking-alcohol-wine-booze-beer-work/story?id=16150294" ], [], [] ]
rgpge
Why are the heaviest elements (e.g. actinides) still found in the crust of the Earth?
Rather than the mantle or core? My intuition tells me that the heavy elements would be more dense and would settle towards the core during formation and failing that, during submergence of continental plates? Also, relating to the question of molecular weight and planetary formation, what about isotopes or any element?...
askscience
http://www.reddit.com/r/askscience/comments/rgpge/why_are_the_heaviest_elements_eg_actinides_still/
{ "a_id": [ "c45oofn" ], "score": [ 3 ], "text": [ "The location of elements in the Earth is controlled by their geochemical behavior, *not* their density.\n\nU and Th (actinides) are[ lithophile elements](_URL_1_) (\"rock loving\" elements that prefer to bonds with oxygen). They end up in the roc...
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[ [ "http://en.wikipedia.org/wiki/Goldschmidt_classification#Siderophile_elements", "http://en.wikipedia.org/wiki/Goldschmidt_classification#Lithophile_elements" ] ]
bnbb8i
why are sounds louder on one side of your ear when you cover the other ear?
explainlikeimfive
https://www.reddit.com/r/explainlikeimfive/comments/bnbb8i/eli5_why_are_sounds_louder_on_one_side_of_your/
{ "a_id": [ "en42bq9" ], "score": [ 4 ], "text": [ "They're not actually louder - there's not suddenly an increase in the ambient sound coming into the ear canal - however, with one ear covered, your conscious awareness of what you're hearing increases." ] }
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2tglhf
why don't they make white tattoo ink so tattoos show up better on black skin?
explainlikeimfive
http://www.reddit.com/r/explainlikeimfive/comments/2tglhf/eli5_why_dont_they_make_white_tattoo_ink_so/
{ "a_id": [ "cnyuuck", "cnyuulu", "cnyvntk" ], "score": [ 2, 4, 3 ], "text": [ "I know they have really bright colors but I don't recall a white", "Long story short, they do, but they don't always show up very well.\n\n_URL_0_", "Well, they do make white tattoo ink, but it'...
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[ [], [ "http://www.whiteinktattooscenter.com/wp-content/uploads/2013/05/white-ink-tattoos-on-black-people.jpg" ], [] ]
1qgh7v
why is the google+ integration so bad for youtube?
explainlikeimfive
http://www.reddit.com/r/explainlikeimfive/comments/1qgh7v/eli5_why_is_the_google_integration_so_bad_for/
{ "a_id": [ "cdcjor4" ], "score": [ 2 ], "text": [ "ELI5 isn't really for \"why is x bad\" questions, as they're subjective by nature, so this has been removed. Try /r/askreddit instead." ] }
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[ [] ]
4xgau7
In Ancient Mesopotamian statues, beards often appear to be ridged and segmented. Was this just the popular style of artistry or is this what their beards would actually look like?
AskHistorians
https://www.reddit.com/r/AskHistorians/comments/4xgau7/in_ancient_mesopotamian_statues_beards_often/
{ "a_id": [ "d6fg1v8", "d6fj57n", "d6fmsrr", "d6hmhhl" ], "score": [ 82, 339, 71, 5 ], "text": [ "Do you have a picture showing exactly what you're referring to?", "(Edit: I should mention I'm a near eastern archaeologist and not specifically a historian) The thing is, ...
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[ [], [], [], [ "https://upload.wikimedia.org/wikipedia/commons/4/44/Sargon_of_Akkad.jpg", "http://ancientpeoples.tumblr.com/post/62424597020/bearded-bulls-head-sumerian-2600-2450-bc-this", "http://www.metmuseum.org/art/collection/search/327527", "https://s-media-cache-ak0.pinimg.com/736x/5f/7f/...