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289cnr
please explain the isis iraq situation.
explainlikeimfive
http://www.reddit.com/r/explainlikeimfive/comments/289cnr/eli5_please_explain_the_isis_iraq_situation/
{ "a_id": [ "ci8q4ph", "ci8qkgw" ], "score": [ 4, 2 ], "text": [ "Ohh man its complicated..\nSo ISIS is the Islamic State of Iraq and Syria. They have been active mainly in Syria fighting against Bashir Al Asad, but have been pushed back there (out of Alepo and denser urban areas) by more ...
[]
[]
[ [], [] ]
cy9mj8
How do people determine the tilt of a planet of direction is relative in space?
askscience
https://www.reddit.com/r/askscience/comments/cy9mj8/how_do_people_determine_the_tilt_of_a_planet_of/
{ "a_id": [ "eyqoydz" ], "score": [ 14 ], "text": [ "We define the ecliptic as the plane that contains the Earths orbit around the sun. We define the tilt of a planet as the angle between the normal direction of the ecliptic and the axis of rotation of the planet." ] }
[]
[]
[ [] ]
5vtzcv
[Book Request] I don't see any books for the Reconquista on the book recommendation list
The books I see are in the lens of muslim communities after the Reconquista, and one specifically about Jewish people. Does anyone have a good book recommendation for a survey of the Reconquista? Thanks!
AskHistorians
https://www.reddit.com/r/AskHistorians/comments/5vtzcv/book_request_i_dont_see_any_books_for_the/
{ "a_id": [ "de4wfo2" ], "score": [ 4 ], "text": [ "Point of clarification. What are you looking for when you say \"a general history of *the Reconquista*?\" Although the underlying crusade ideology is there for the Christians, and as time wore on Muslims definitely realized their al-Andalus (by t...
[]
[]
[ [] ]
16n24x
Why did CPUs stopped at around ~3-4GHz?
What I mean is, 10 years ago I would think that today we will have 30GHz processors, instead we get more cores. Is there a physical barrier?
askscience
http://www.reddit.com/r/askscience/comments/16n24x/why_did_cpus_stopped_at_around_34ghz/
{ "a_id": [ "c7xi655", "c7xrrnv" ], "score": [ 10, 4 ], "text": [ "See:\n\n_URL_0_ \n_URL_1_", "The heat leaked increases at a rate faster than the clock speed. This increase becomes pretty ridiculous so that the cooling systems needed are not affordable to the average person and the...
[]
[]
[ [ "http://www.reddit.com/r/askscience/comments/ngv50/why_have_cpus_been_limited_in_frequency_to_around/", "http://www.reddit.com/r/askscience/comments/y8anh/why_do_i_have_cpu_with_8_3_ghz_cores_and_not_1_24/" ], [] ]
1ekmbg
What festivals did the romans celebrate (pre-christianity)?
AskHistorians
http://www.reddit.com/r/AskHistorians/comments/1ekmbg/what_festivals_did_the_romans_celebrate/
{ "a_id": [ "ca16o1u" ], "score": [ 5 ], "text": [ "The Romans celebrated plenty of festivals, and I'll highlight a couple of the more important ones for you.\n\n* **Lupercalia:** This is possibly the most famous Roman festival, along with Saturnalia. It was celebrated during February (13-15) and...
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[]
[ [] ]
6t9jw7
why is if more harmful to the human body to be exposed to freezing water than it is to be exposed to air of a similar temperature?
I've always heard that spending even a short amount of time in an extremely cold body of water will most likely lead to hypothermia or even death, but spending the same amount of time outside in extreme temperatures doesn't seem to have the same effect.
explainlikeimfive
https://www.reddit.com/r/explainlikeimfive/comments/6t9jw7/eli5_why_is_if_more_harmful_to_the_human_body_to/
{ "a_id": [ "dlixfiz", "dlixipe", "dlj7i91" ], "score": [ 5, 11, 2 ], "text": [ "The heat capacity of water is much greater than air meaning it can absorb heat from the body much faster. This is basically the idea behind how you can reach into a newly opened oven without harm but d...
[]
[]
[ [], [], [] ]
50l1qn
How and when were tanks, semiautomatic weapons and planes started being deployed in warfare?
Sorry for possible grammar errors, english is not my mother tongue. I wanted to know what exactly changed so much in warfare from 1870's to 1914. In WW1 we see automatic weapons, tanks, and planes but just a few decades ago armies were using rifles and cannons that weren't so different from past centuries. Was WW1 the...
AskHistorians
https://www.reddit.com/r/AskHistorians/comments/50l1qn/how_and_when_were_tanks_semiautomatic_weapons_and/
{ "a_id": [ "d756slw" ], "score": [ 3 ], "text": [ "The Second Industrial Revolution happened.\n\nGenerally considered to have started in 1870, the Second Industrial Revolution saw the development of a wide range of technologies, manufacturing techniques and chemicals that made many of the weapons...
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[ [] ]
1z74po
what is modern art and what determines the price?
Example: _URL_0_
explainlikeimfive
http://www.reddit.com/r/explainlikeimfive/comments/1z74po/eli5_what_is_modern_art_and_what_determines_the/
{ "a_id": [ "cfr3w2a" ], "score": [ 3 ], "text": [ "Whatever the artist feels he is owed is weighed against public appraisal. It’s supply and demand, but on a very intimate scale, that determines the price. That is to say, the worth of the piece is the highest value a person wishes to pay. If the ...
[]
[ "http://www.christies.com/lotfinder/paintings/christopher-wool-blue-fool-5315238-details.aspx" ]
[ [] ]
5znnau
why is depression such a pervasive theme throughout reddit?
explainlikeimfive
https://www.reddit.com/r/explainlikeimfive/comments/5znnau/eli5_why_is_depression_such_a_pervasive_theme/
{ "a_id": [ "dezjeoe", "dezkp9d" ], "score": [ 6, 17 ], "text": [ "Because a lot of people suffer from depression and better to make a joke of it than wallow in it. I think Reddit has almost helped me with my depression because I don't take it as seriously anymore.", "Reddit is a fairl...
[]
[]
[ [], [] ]
3aj076
why are rabbits associated with sexual things like playboy?
explainlikeimfive
http://www.reddit.com/r/explainlikeimfive/comments/3aj076/eli5_why_are_rabbits_associated_with_sexual/
{ "a_id": [ "csd1ln0" ], "score": [ 10 ], "text": [ "Rabbits have a reputation of breeding prolifically, which leads to their reputation of having sex very often." ] }
[]
[]
[ [] ]
eaee56
difference between memory and ssd
Looking at laptops and confused between memory and SSD.
explainlikeimfive
https://www.reddit.com/r/explainlikeimfive/comments/eaee56/eli5_difference_between_memory_and_ssd/
{ "a_id": [ "fapxbsb", "faq4829" ], "score": [ 19, 4 ], "text": [ "Memory typically refers to RAM (random access memory) where as SSD (solid state drive) refers to storage.\n\nEasiest way to know the difference is think of RAM as a work table and SSD or other storage device like a hard dri...
[]
[]
[ [], [] ]
ablkcw
how does mass hysteria work and how can it manifest physical symptoms?
/title
explainlikeimfive
https://www.reddit.com/r/explainlikeimfive/comments/ablkcw/eli5how_does_mass_hysteria_work_and_how_can_it/
{ "a_id": [ "ed2007g" ], "score": [ 2 ], "text": [ "It's pretty much a huge case of fomo with the placebo effect. You see a bunch of people doing something and your mind thinks that the might be something triggering it that effects you so you begin to physically manifest something like an uncontro...
[]
[]
[ [] ]
3fiu2i
why does hard cheese which has been maturing for years have a sell-by date of only a few weeks?
Thanks!
explainlikeimfive
http://www.reddit.com/r/explainlikeimfive/comments/3fiu2i/eli5_why_does_hard_cheese_which_has_been_maturing/
{ "a_id": [ "ctozndn", "ctp0qe6", "ctp19lw", "ctp1ho2", "ctp6qii", "ctp8o17", "ctpd0ns", "ctple7m", "ctpsawz" ], "score": [ 238, 7, 43, 14, 9, 5, 2, 2, 2 ], "text": [ "It's been cut.\n\nAs long as the outside of the cheese is entirely...
[]
[]
[ [], [], [], [], [], [], [], [], [] ]
5k1mjr
why is video ram (like gddr5) so much faster than regular ram (like ddr3 or ddr4)?
explainlikeimfive
https://www.reddit.com/r/explainlikeimfive/comments/5k1mjr/eli5_why_is_video_ram_like_gddr5_so_much_faster/
{ "a_id": [ "dbknthx", "dbkpgfa", "dbkqd1o" ], "score": [ 11, 43, 2 ], "text": [ "I know that the VRAM (video RAM) is only faster because it can be without losing stability. \n\nThere are also less compatibility issues, because it serves only one purpose, and doesn't have to juggle...
[]
[]
[ [], [], [] ]
3gg2um
in david attenborough documentaries, how do they get the camera inside each respective insect/animals home?
explainlikeimfive
http://www.reddit.com/r/explainlikeimfive/comments/3gg2um/eli5_in_david_attenborough_documentaries_how_do/
{ "a_id": [ "ctxstgc" ], "score": [ 3 ], "text": [ "If you have the DVD/Blu-Ray sets, watch the behind-the-scenes extras. \n\nThese nature photographers spend months and months working to catch the perfect moment (really makes the viewer marvel and appreciate their contributions to public knowled...
[]
[]
[ [] ]
bb91tg
What is the price difference between geothermal energy and fossil fuel energy?
askscience
https://www.reddit.com/r/askscience/comments/bb91tg/what_is_the_price_difference_between_geothermal/
{ "a_id": [ "ekhnnly" ], "score": [ 6 ], "text": [ "It really *really* depends on where you're trying to get geothermal energy from. In Iceland, which has tons of volcanic activity and gets all its electricity from geothermal, electricity prices are about half the cost in other Nordic countries.\...
[]
[]
[ [ "http://www.geo.tu-freiberg.de/oberseminar/os06_07/Kathrin%20Kranz.pdf", "https://www.statice.is/publications/news-archive/energy/electricity-prices-in-iceland-and-in-the-nordic-countries/" ] ]
2erc0r
Help identifying a Japanese battle flag from WWII
_URL_0_ Background: This flag was taken off the body of a dead Japanese soldier in the Pacific theater during 1942 (I can get a few more details on that later). It belongs to my wife's family and I wanted to see if any of you could give me more information, such as a translation of the text, which I understand is usua...
AskHistorians
http://www.reddit.com/r/AskHistorians/comments/2erc0r/help_identifying_a_japanese_battle_flag_from_wwii/
{ "a_id": [ "ck2b6ak", "ck2ibtq" ], "score": [ 2, 3 ], "text": [ "I can't answer your question directly, but you might try x-posting this /r/japan", "I can't read all of it--the vertical text on the sides is quite difficult and I will leave it to somebody else. But the text on the top ...
[]
[ "http://snag.gy/IgeZO.jpg" ]
[ [], [] ]
7rbul5
how come the military is "always recruiting" and are all countries like this?
[deleted]
explainlikeimfive
https://www.reddit.com/r/explainlikeimfive/comments/7rbul5/eli5_how_come_the_military_is_always_recruiting/
{ "a_id": [ "dsvoqrf", "dsvpsug", "dsvr8cv", "dsvru9o", "dsvsneh" ], "score": [ 10, 3, 5, 2, 2 ], "text": [ "People are always leaving and moving up even when an army downsizes. Ergo there are always needs for replacements at the bottom. \n\nNow you may not ge...
[]
[]
[ [], [], [], [], [] ]
85vkyj
how do people doing gymnastics always land on their feet?
explainlikeimfive
https://www.reddit.com/r/explainlikeimfive/comments/85vkyj/eli5_how_do_people_doing_gymnastics_always_land/
{ "a_id": [ "dw0dqnv" ], "score": [ 2 ], "text": [ "They spend years failing to land on their feet. Its an enormous amount of practice, and even then they aren't always perfect." ] }
[]
[]
[ [] ]
1xeh0s
i'm an adult. why do i always dream about school?
I've been out of college for eight years. In my four years of time there, I dropped out of exactly one course because I was too disinterested to attend class. Ultimately it had no negative effect on my graduation. And yet, since that year, I've had the same dream at least twice a week: I'm back in college, I've compl...
explainlikeimfive
http://www.reddit.com/r/explainlikeimfive/comments/1xeh0s/eli5_im_an_adult_why_do_i_always_dream_about/
{ "a_id": [ "cfamr1x", "cfamt1p" ], "score": [ 2, 4 ], "text": [ "Because your school years were the most formative years of your life.", "You can think of it as a very, very mild form of Post Traumatic Stress Disorder (PTSD).\n\nBasically, you dream of it because you went through it. ...
[]
[]
[ [], [] ]
177ivh
Would it be inaccurate to say that in general, the common people of modern first world countries eat better than medieval European royalty?
I'm sure medieval kings were given the best food the land could offer, but back then they did not have very good sanitation or preservation techniques. Their variety in food was also probably very limited because they could not import foods from very far away. Nowadays however, any person in the first world could go t...
AskHistorians
http://www.reddit.com/r/AskHistorians/comments/177ivh/would_it_be_inaccurate_to_say_that_in_general_the/
{ "a_id": [ "c82yjqy", "c833wvz", "c833zp2" ], "score": [ 13, 11, 52 ], "text": [ "In terms of quality and variety, I would assume you are right. Although, they had vats of wine, honey, and all sorts of cheeses and wild game, I imagine the quality was not great. \n\nIt's also inter...
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[]
[ [ "http://www.slideshare.net/whitehouse/menu-2012-uk-state-dinner" ], [ "http://www.youtube.com/watch?v=oH5O_fCstyI" ], [] ]
5met1x
how can someone who lost all movement from below the neck breath without aid?
explainlikeimfive
https://www.reddit.com/r/explainlikeimfive/comments/5met1x/eli5_how_can_someone_who_lost_all_movement_from/
{ "a_id": [ "dc2zkll" ], "score": [ 2 ], "text": [ "In some cases they absolutely cannot, and must use a machine such as an \"iron lung\" or respirator.\n\nIn other cases, although their voluntary nerves aren't working, the other nerves that run automatic systems are still in good shape." ] }
[]
[]
[ [] ]
22w62d
why do adolescent girls seem to be more obsessed with boy pop stars (think justin bieber, boy bands, the beatles, etc.) than adolescent boys are obsessed with female pop stars?
explainlikeimfive
http://www.reddit.com/r/explainlikeimfive/comments/22w62d/eli5_why_do_adolescent_girls_seem_to_be_more/
{ "a_id": [ "cgqyl0x", "cgqylcf", "cgqzmet", "cgr04tw", "cgr0621", "cgr1c1t", "cgr1zje", "cgr2wjj", "cgr4fux", "cgr5nb3" ], "score": [ 5, 58, 3, 16, 11, 6, 7, 4, 2, 2 ], "text": [ "Pop stars maybe. Trust me, as an adolescent,...
[]
[]
[ [], [], [], [], [], [], [], [], [], [] ]
a1zdfk
Does Crossing-Over in Meiosis result in new genes?
Or does it only provide new genetic combinations? Thanks in advance!
askscience
https://www.reddit.com/r/askscience/comments/a1zdfk/does_crossingover_in_meiosis_result_in_new_genes/
{ "a_id": [ "eavizb7" ], "score": [ 2 ], "text": [ "It's not clear from your question whether you mean new alleles (\"versions\" of genes) or whole new genetic loci (sections of the chromosome), but the answer is yes in both cases!\n\n[Crossing-over](_URL_0_) happens anywhere along the chromosome,...
[]
[]
[ [ "https://en.wikipedia.org/wiki/Chromosomal_crossover", "https://en.wikipedia.org/wiki/Homologous_chromosome", "https://en.wikipedia.org/wiki/Gene_duplication", "https://en.wikipedia.org/wiki/Unequal_crossing_over" ] ]
92yods
How many mass extinctions were there, and how do we know?
I've heard that there have been five mass extinction events through Earth's history, and that an increasing number of scientists say we're in the middle of a sixth. But I've also heard that those five happened in the last half-billion years. Did no others happen earlier? How do we know a mass extinction event happen...
askscience
https://www.reddit.com/r/askscience/comments/92yods/how_many_mass_extinctions_were_there_and_how_do/
{ "a_id": [ "e39fjm3", "e39fk1d", "e39g2bx", "e39my5z", "e3a5reo", "e3a7x2j" ], "score": [ 5, 8, 2, 5, 4, 2 ], "text": [ "You can look at the fossil record and see periods of great diversity, many fossils , followed by periods of few fossils and little diver...
[]
[]
[ [], [], [ "https://en.m.wikipedia.org/wiki/Great_Oxygenation_Event" ], [ "https://en.wikipedia.org/wiki/Ediacaran_biota", "https://en.wikipedia.org/wiki/Cryogenian" ], [], [] ]
59mytl
why arent any saudi royals on the top billionaire lists? are they not filthy rich from oil?
explainlikeimfive
https://www.reddit.com/r/explainlikeimfive/comments/59mytl/eli5_why_arent_any_saudi_royals_on_the_top/
{ "a_id": [ "d99qt9n", "d99qy2k", "d99xsu5", "d99z5t9" ], "score": [ 10, 5, 3, 3 ], "text": [ "Those guys are also not particularly transparent. Since Saudi Arabia is an absolute monarchy, the country's budget and state investment funds are also the royal family's own walle...
[]
[]
[ [], [], [], [] ]
3rp0op
why does it matter that young people don't vote?
explainlikeimfive
https://www.reddit.com/r/explainlikeimfive/comments/3rp0op/eli5why_does_it_matter_that_young_people_dont_vote/
{ "a_id": [ "cwq0v7q", "cwq0yxn", "cwq4uh8" ], "score": [ 4, 2, 2 ], "text": [ "Broadly speaking, young people not voting shows there is a lack of engagement. This can mean they don't feel like anything will change, or can change. \n \nThis matters because for democracy to function...
[]
[]
[ [], [], [] ]
1u8b3h
I am a Roman equite from the age of Augustus examining Rome during the reign of Constantine. What has changed most noticeably? Is the new Rome even recognizable to me?
I understand that answers about life for commoners in Roman times must often resort to speculative and circumstantial evidence. I would appreciate anybody who can introduce us to some of the prevailing views about how life in Rome changed as the empire evolved. EDIT: Should have been "eques", not equite.
AskHistorians
http://www.reddit.com/r/AskHistorians/comments/1u8b3h/i_am_a_roman_equite_from_the_age_of_augustus/
{ "a_id": [ "cefnlcu", "cefol63", "cefs5sy" ], "score": [ 86, 7, 26 ], "text": [ "^I'm ^not ^sure ^what ^you ^mean ^by ^\"examining ^Rome\". ^If ^you ^mean ^something ^like ^walking ^through ^the ^city ^of ^Rome, ^this ^would ^be ^my ^answer:\n\n & nbsp;\n\nRome has changed massive...
[]
[]
[ [], [], [] ]
5jh8s8
why does eating human flesh lead to "the shakes"?
For the record - I'm not planning on any crazy dietary changes. I just watched The Book of Eli and it's mentioned repeatedly, I'm curious as to what the correlation is.
explainlikeimfive
https://www.reddit.com/r/explainlikeimfive/comments/5jh8s8/eli5_why_does_eating_human_flesh_lead_to_the/
{ "a_id": [ "dbg74n3", "dbg7cor" ], "score": [ 5, 25 ], "text": [ "They probably adapted the real disease [kuru](_URL_0_). It's a prion disease, similar to Mad Cow disease. A prion is a protein that is folded up wrong. Besides not doing its normal job right, the prion makes other proteins ...
[]
[]
[ [ "https://en.m.wikipedia.org/wiki/Kuru_(disease\\)" ], [] ]
5eqqbv
what actually are the trigometric fuctions?
I pretty much know the basics of trig; how to find sides, angles, unit circle, graphs, etc. So here's my question: I know a tangent is a line that touches a circle at one point. But then what actually is a 'sine' or a 'cosine'? It would also help telling me why the trigonometic process is done. (Not getting the answe...
explainlikeimfive
https://www.reddit.com/r/explainlikeimfive/comments/5eqqbv/eli5_what_actually_are_the_trigometric_fuctions/
{ "a_id": [ "daejoax", "daen9lm", "daepsa1" ], "score": [ 12, 2, 3 ], "text": [ "EE student bored at a huge family Thanksgiving meal, I'll give this a shot.\n\nThe sine function takes an angle, traditionally labeled 'theta', as its input, and spits out the corresponding ratio betwe...
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[]
[ [ "http://zonalandeducation.com/mstm/physics/mechanics/forces/forceComponents/forceComponents2.gif", "https://share.ehs.uen.org/sites/default/files/images/unit8l3.7_graph1.img_assist_custom.png", "http://www.nextlevelmaths.com/resources/trigonometry/sohcahtoa/images/triangle.png", "http://jwilson.co...
an27d5
Why doesn't the US-Canada border follow the St. Lawrence River all the way to the Atlantic?
With some exceptions, the US-Canada border is mostly determined by the 49th parallel from Vancouver Island to Lake Superior in the West and then by the Great Lakes in the Midwest. The border then follows the St. Lawrence out of Lake Ontario for about 100 miles before cutting across the 45th parallel for about 150 miles...
AskHistorians
https://www.reddit.com/r/AskHistorians/comments/an27d5/why_doesnt_the_uscanada_border_follow_the_st/
{ "a_id": [ "efqbjcd" ], "score": [ 9 ], "text": [ "A very brief answer can come from looking at patterns of European colonialism. The Mississippi river, the St. Lawrence, the Columbia, the Fraser, all these are rivers that when they reach the ocean they come out in the middle of a political unit ...
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[]
[ [] ]
1kb7u2
What type of weapons would have been available to medieval peasants?
Would they have been limited to farming tools or would they have something like a family sword if their lord called them to war?
AskHistorians
http://www.reddit.com/r/AskHistorians/comments/1kb7u2/what_type_of_weapons_would_have_been_available_to/
{ "a_id": [ "cbnaghm", "cbnd87i", "cbo71gh" ], "score": [ 2, 3, 2 ], "text": [ "A peasant levy was not often called upon but there does exists various folk wrestling and stick fighting traditions that may vary from region to region. \n\nPaulus Hector Mair collected fighting treatis...
[]
[]
[ [ "http://wiktenauer.com/wiki/Paulus_Hector_Mair" ], [], [] ]
3qxdfv
At what point did European settlers outnumber Native Americans in what would become the modern United States?
Was either group aware of the shift? When did Americans begin to see the natives as a smaller group collectively than themselves?
AskHistorians
https://www.reddit.com/r/AskHistorians/comments/3qxdfv/at_what_point_did_european_settlers_outnumber/
{ "a_id": [ "cwjm0qq", "cwjrak0" ], "score": [ 3, 9 ], "text": [ "I think Thornton's [American Indian Holocaust and Survival: A Population History Since 1492] (_URL_5_) would probably be a good resource for answering your question (it's at my work office atm, so I'm reluctant to give a mor...
[]
[]
[ [ "http://www.usdakotawar.org/", "https://s-media-cache-ak0.pinimg.com/736x/f7/76/be/f776be148f2f41ab4ba6988b0b22550b.jpg", "https://en.wikipedia.org/wiki/Clatsop", "https://en.wikipedia.org/wiki/List_of_U.S._communities_with_Native_American_majority_populations", "https://en.wikipedia.org/wiki/...
fed03x
why does the body consume carbohydrates first and then fats when exercising?
[deleted]
explainlikeimfive
https://www.reddit.com/r/explainlikeimfive/comments/fed03x/eli5_why_does_the_body_consume_carbohydrates/
{ "a_id": [ "fjn6k2v", "fjn6xwl", "fjnfb0k" ], "score": [ 12, 8, 2 ], "text": [ "The actual answer is a bit more complicated than that. What cells actually use for fuel is ATP, which is an energetic protein that we make using carbohydrates, fats, and other things as a fuel source.\...
[]
[]
[ [], [], [] ]
6bg90k
What is actually happening when I hear my timber framed house 'crack'?
I understand that heating and cooling is responsible for it but are tiny cracks actually being made every time I hear it?
askscience
https://www.reddit.com/r/askscience/comments/6bg90k/what_is_actually_happening_when_i_hear_my_timber/
{ "a_id": [ "dhmkurc", "dhmkzlw", "dhml1y5", "dhmrg2m" ], "score": [ 198, 37, 19, 9 ], "text": [ "It would be better described as creaking rather than cracking. When a door creaks, the hinges aren't cracking, there's just resistance that builds up until friction can no long...
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[]
[ [], [], [], [] ]
alby6r
why can't a country in a trade surplus be sustained in that position indefinitely?
explainlikeimfive
https://www.reddit.com/r/explainlikeimfive/comments/alby6r/eli5_why_cant_a_country_in_a_trade_surplus_be/
{ "a_id": [ "efcn16a" ], "score": [ 7 ], "text": [ "It can.\n\nImagine you have a job at a convenience store where they give you a 50% discount on baseball cards. You don’t care for them much, but your friend does. He regularly buys them from you for 90% of list. You never buy anything from him.\...
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[]
[ [] ]
9w6uex
This Week's Theme: Immigrants and Emigrants
AskHistorians
https://www.reddit.com/r/AskHistorians/search?q=flair%3AMigrants&sort=new&restrict_sr=on&t=all
{ "a_id": [ "e9i4agt" ], "score": [ 2 ], "text": [ "**Current:** Immigrants and Emigrants\n\n**On Deck:** Trauma\n\n**In the Hole:** The Balkans\n\nRemember to ask theme-related questions in [a new thread!](_URL_1_)! If your submission doesn't get automatically flaired, [send us a modmail](_URL_0_...
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[ [ "https://www.reddit.com/message/compose?to=%2Fr%2FAskHistorians", "https://www.reddit.com/r/AskHistorians/submit?selftext=true" ] ]
61dbl4
- why is citizen kane considered to be the pinnacle of movie making?
What is it about Citizen Kane that makes it such a highly regarded movie? A lot of the time when someone is talking about if a movie is good or not they'll say something along the lines of "It's no Citizen Kane or anything". It almost seemed to be used as a benchmark of moviemaking. So why is this movie so highly res...
explainlikeimfive
https://www.reddit.com/r/explainlikeimfive/comments/61dbl4/eli5_why_is_citizen_kane_considered_to_be_the/
{ "a_id": [ "dfdmxgm", "dfdok7r", "dfdoxwj", "dfdy2fs", "dfe28c6", "dfe2rwu", "dfe324t", "dfe5pcb" ], "score": [ 11, 881, 55, 12, 32, 3, 3, 2 ], "text": [ "It's really more popular with people in the movie industry. It doesn't normally top th...
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[ [], [], [], [], [ "https://www.youtube.com/watch?v=xbGbqRWwC_Q" ], [], [], [] ]
80nw7e
what is the difference between federal debt and u.s. treasury securities?
explainlikeimfive
https://www.reddit.com/r/explainlikeimfive/comments/80nw7e/eli5_what_is_the_difference_between_federal_debt/
{ "a_id": [ "duwvysd" ], "score": [ 2 ], "text": [ "The debt is issued through the use of US Treasury securities. The government sells a bond, and the money collected from the bond buyer increases the debt until the bond is paid back." ] }
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[ [] ]
2n6l6c
why does semen lose its white color after 5 min?
What makes it white and why is it not white anymore after 5 min?
explainlikeimfive
http://www.reddit.com/r/explainlikeimfive/comments/2n6l6c/eli5_why_does_semen_lose_its_white_color_after_5/
{ "a_id": [ "cmay4ra", "cmb2pff", "cmb58tj", "cmb5dtq", "cmbk4j4" ], "score": [ 67, 15, 23, 5, 2 ], "text": [ "Ok, so: semen contains very little actual spermatozoa and a lot of other components, one of which are alkaloids produced by prostate to - basically - neutr...
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[ [], [], [], [], [] ]
15a2d7
sinuses
Why does my throat seem to swell up and go numb after a sneezing spell?
explainlikeimfive
http://www.reddit.com/r/explainlikeimfive/comments/15a2d7/eli5_sinuses/
{ "a_id": [ "c7kme3k", "c7kmo3a" ], "score": [ 2, 6 ], "text": [ "More importantly... why can't my girlfriend taste anything anymore?? Some kind of sinus infection that's lasted weeks ;_;", "Sinuses are hollow cavities in the skull to lighten the bone structure. They are lined with mu...
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[]
[ [], [ "http://www.webmd.com/allergies/picture-of-the-sinuses" ] ]
4txahf
if you start off completely awake and energized but then start dozing off during a boring class or a study session, what exactly is happening physiologically to cause this ?
explainlikeimfive
https://www.reddit.com/r/explainlikeimfive/comments/4txahf/eli5_if_you_start_off_completely_awake_and/
{ "a_id": [ "d5l38kp", "d5lajv5", "d5lfgcb", "d5lq6cm", "d5ls0u4", "d5lscwh", "d5lsj2g", "d5lt0pj", "d5ltaqj", "d5ltatr", "d5ltsbh", "d5luhrv" ], "score": [ 601, 33, 174, 24, 2, 2, 4, 2, 5, 2, 3, 2 ], "text": [ ...
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[ [], [], [], [], [], [], [], [], [], [], [], [] ]
btlpao
if supermarkets have a defined science/art as to where products are located, why are they all different?
My experience from Tesco, Sainsburys, ASDA, Waitrose and M & S show that in every single store the format is always different. Either completely mirrored, flipped on itself, some products coupled with others in a different way, and freezer/fridge aisles sometimes together sometimes apart, sometimes by the entrance, som...
explainlikeimfive
https://www.reddit.com/r/explainlikeimfive/comments/btlpao/eli5_if_supermarkets_have_a_defined_scienceart_as/
{ "a_id": [ "ep07z7p", "ep34wvt" ], "score": [ 3, 2 ], "text": [ "Numerous factors- \n\n1 Store size. Different stores are different sizes, and shapes depending on the area they are situated and the availble space/ planned market.. What works for one floor plan doesn't neccesarily work for...
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[ [], [] ]
3js7nv
why do people with loads of money still attempt to earn more money? if you have millions in the bank isn't that more than enough?
I was thinking about this all day. If I had £1 million in the bank, I could live off the interest for the rest of my life. I appreciate that just because you're loaded you don't immediately quit your job, but why do millionaires still have the desire to earn more. What's the real difference between a millionaire and a ...
explainlikeimfive
https://www.reddit.com/r/explainlikeimfive/comments/3js7nv/eli5_why_do_people_with_loads_of_money_still/
{ "a_id": [ "curtt7i", "curvu2y", "curwqwu" ], "score": [ 7, 3, 2 ], "text": [ "Generally I would say that people who are millionaires tend to have a high performance drive. They desire to always perform better. This is what made them wealthy in the first place, and this is what ma...
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[ [], [], [] ]
5j4rkk
What is the longest "unbroken" chain of royal or dynastic succession in known history?
I ask broadly because I don't even know how to clarify this question. One answer may be in terms of leaders who "choose" the subsequent leader pursuant to some ritual, but I understand that it may be more complex than that. Basically I'm wondering about the longest line of succession without a major intervening fact...
AskHistorians
https://www.reddit.com/r/AskHistorians/comments/5j4rkk/what_is_the_longest_unbroken_chain_of_royal_or/
{ "a_id": [ "dbdhld9", "dbdilgm", "dbds6ni" ], "score": [ 429, 36, 17 ], "text": [ "Japan has the oldest continuous, hereditary monarchy in the world -- and would, I believe, even qualify as oldest if we included non-hereditary or interrupted-hereditary successions. The Japanese ro...
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[ [ "https://en.wikipedia.org/wiki/Emperor_Kinmei" ], [], [] ]
25wbl2
Why is it that humans can be sustained on some leafy plants (spinach, lettuce, kale, etc) but not others (ferns, tree & and flower leaves, etc)?
Why can sustainable nutrition come from some plants, but not others?
askscience
http://www.reddit.com/r/askscience/comments/25wbl2/why_is_it_that_humans_can_be_sustained_on_some/
{ "a_id": [ "chlp9pt", "chlrfzr" ], "score": [ 2, 2 ], "text": [ "It depends on what that source has to offer. Most leafy plants commonly eaten are considered \"greens\" like Kale, Spinach, Arugula, etc., and are eaten for the vitamin and mineral content. \"Greens\" are an essentially non-...
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[ [], [] ]
e2fvdf
how to barcode scanners instantly detect what an item is, despite the barcode being at any angle and often on a crinkled surface, completeley changing the look of the code from the scanner's perspective?
explainlikeimfive
https://www.reddit.com/r/explainlikeimfive/comments/e2fvdf/eli5_how_to_barcode_scanners_instantly_detect/
{ "a_id": [ "f8v6ec7", "f8v6gkf", "f8v8web" ], "score": [ 4, 2, 4 ], "text": [ "The lasers that read the barcode hit it from many angles and scan it very quickly. Also barcodes have something like a checksum, where it's easy to recognize if the data that was read is garbage and nee...
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[ [], [], [] ]
5f6ywg
Is there a historical reason why the US military says klick instead of kilometre?
AskHistorians
https://www.reddit.com/r/AskHistorians/comments/5f6ywg/is_there_a_historical_reason_why_the_us_military/
{ "a_id": [ "daj38ya" ], "score": [ 9 ], "text": [ "It's not official, it is military slang, and is used purely because it is easier to say." ] }
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[ [] ]
3jzq5e
why do most websites have character limits for passwords while at the same time they force you to have an upper/lowercase letter, and a number to make your password more secure. wouldn't removing the character limit and allowing much longer passwords make them more secure than 16 characters?
explainlikeimfive
https://www.reddit.com/r/explainlikeimfive/comments/3jzq5e/eli5_why_do_most_websites_have_character_limits/
{ "a_id": [ "cutmere", "cutmnwh", "cutoxx9", "cutp6kj", "cuts0mc", "cutu292", "cutw0w8", "cutzri8", "cuu1wd4", "cuu45t3", "cuu4e5h" ], "score": [ 258, 4, 31, 5, 137, 3, 34, 2, 2, 3, 3 ], "text": [ "Convention.\n\n\nThe...
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[ [], [], [], [ "https://youtu.be/8ZtInClXe1Q" ], [], [], [], [], [], [], [] ]
a00rpw
Whats the difference between Centrifugal and Centripetal force?
askscience
https://www.reddit.com/r/askscience/comments/a00rpw/whats_the_difference_between_centrifugal_and/
{ "a_id": [ "eadp9tj", "eadtgqn" ], "score": [ 16, 21 ], "text": [ "The centripetal force points toward the axis of rotation, and the centrifugal force points away from the axis of rotation.", "Its often taught in PHY 101 courses that the centripetal force is \"real\" while the centrif...
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[ [], [] ]
4ggeu9
what's actually happening when someone overeats on a regular basis and their stomach "expands"? what about in reverse when their stomach gets "smaller"?
explainlikeimfive
https://www.reddit.com/r/explainlikeimfive/comments/4ggeu9/eli5_whats_actually_happening_when_someone/
{ "a_id": [ "d2hcijg" ], "score": [ 22 ], "text": [ "It's not just a figure of speech. Your stomach can physically expand/stretch. [Competitive eaters expand their stomachs for competition using water](_URL_0_). It really is like a balloon in a way. The size of the actual organ doesn't change,...
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[ [ "http://www.foodchallenges.com/tips/how-to-expand-your-stomach-using-water/" ] ]
40bvjq
rental car insurance.
Are there scenarios where it is beneficial to purchase it when you already have personal auto insurance?
explainlikeimfive
https://www.reddit.com/r/explainlikeimfive/comments/40bvjq/eli5_rental_car_insurance/
{ "a_id": [ "cysymf3", "cysyuyz", "cyszb1d", "cyt3cnk", "cyt3uho" ], "score": [ 3, 5, 2, 2, 2 ], "text": [ "When on vacation I had a mid-sized cheap car reserved for me. They tried to get me to get a much more fancy and expensive car. My insurance alone would not ha...
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[ [], [], [], [], [] ]
rkymk
If Alpha Centauri had a solar system like ours, how big would the outer planet's orbit appear in the sky if visible with the naked eye?
Or to put it another way, how big would the ellipse of that orbit be if drawn on a star map? Or to put it one more way, if the outer orbit was somehow magically visible to the naked eye, would the angle it transcribed on the sky be lower than the angular resolution of the human eye? I have a wonderful image in my hea...
askscience
http://www.reddit.com/r/askscience/comments/rkymk/if_alpha_centauri_had_a_solar_system_like_ours/
{ "a_id": [ "c46nfn6" ], "score": [ 3 ], "text": [ "If the planetary system was completely face on and if we assume that it's an Earth like planet orbiting at 1 AU, then it would appear approximately 4x10^-4 degrees wide. That's about 0.012 arc minutes, and a quick wiki check says that the best a...
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[ "http://en.wikipedia.org/wiki/Naked_eye#Basic_accuracies" ]
[ [] ]
2vud2t
Can you name some important historical travelogues?
I know of ibn battua book, and Periplus of the Erythraean Sea.Are there any others that histroins use as primary sources for undercover regions.
AskHistorians
http://www.reddit.com/r/AskHistorians/comments/2vud2t/can_you_name_some_important_historical_travelogues/
{ "a_id": [ "col0dpk", "colamhm" ], "score": [ 3, 2 ], "text": [ "Forgive me, I am not certain what you mean by 'undercover regions'. Lady Mary Wortley Montagu's travel writings on Turkey and other countries are used as primary sources. Her relish in appealing to her audiences means her ...
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[ [], [ "https://classesv2.yale.edu/access/content/user/haw6/Vikings/voyagers.html", "http://books.google.com/books?id=UPCworiqUqcC&source=gbs_book_other_versions", "http://books.google.com/books/about/The_Diligent.html?id=0YILMba_EnoC", "http://www.brycchancarey.com/equiano/index.htm" ] ]
31fl5x
During WW2, were there any significant acts of sabotage executed by the Axis powers on U.S. soil?
AskHistorians
http://www.reddit.com/r/AskHistorians/comments/31fl5x/during_ww2_were_there_any_significant_acts_of/
{ "a_id": [ "cq13nb7" ], "score": [ 27 ], "text": [ "The case of Ex Parte Quirin is of note here, if only to show how inept German sabotage was for the time. A handful of covert German operatives deposited by submarine on the American eastern coast landed in uniform, to comply with the laws of war...
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19pzvd
[mod post] coming soon...on rules and mods.
Salutations! Recently, the moderators of /r/explainlikeimfive sat down together on IRC to discuss some issues we've been having, changes to be made, and the future of this subreddit. ---- We have three things we want to do over the next 1-3 weeks: * **Rules:** We will be changing the sidebar rules to make them more...
explainlikeimfive
http://www.reddit.com/r/explainlikeimfive/comments/19pzvd/mod_post_coming_soonon_rules_and_mods/
{ "a_id": [ "c8qb0sm" ], "score": [ 9 ], "text": [ "Can we make sure the rules do more to encourage searching for answers first? Especially around big news events, the old classics of '3d printing' and 'schrodingers cat' come up constantly too. A giant red bar that flashes up when you mouse over s...
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1x9xaq
How accurate are the assumptions made by the blog medievalpoc concerning nonwhite peoples in medieval Europe?
AskHistorians
http://www.reddit.com/r/AskHistorians/comments/1x9xaq/how_accurate_are_the_assumptions_made_by_the_blog/
{ "a_id": [ "cf9gsac", "cf9obsi" ], "score": [ 2, 16 ], "text": [ "What are the assumptions concerning non-white people in medieval Europe? Please outline the specific assumptions you feel are being made by the blog.", "So, for the record there was [this conversation last week](_URL_0_...
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[ [], [ "http://www.reddit.com/r/AskHistorians/comments/1wuu4g/the_blog_medievalpoctumblrcom_asserts_that_black" ] ]
5475ir
When did Americans start using French words and phrases, and why are they so prevalent?
I'm sorry if this breaks the current event rule, but I feel that the question really spans a long period of time, not only the present. _URL_0_ Here is a list of French phrases that americans use. I'm not sure if other english speakers also use them, or even other languages, but I would be interested to know if they ...
AskHistorians
https://www.reddit.com/r/AskHistorians/comments/5475ir/when_did_americans_start_using_french_words_and/
{ "a_id": [ "d7zjf34" ], "score": [ 9 ], "text": [ "Although English is a Germanic language, approximately 30% of English vocabulary comes from French in one form or another. This is largely caused by an event called the Norman Conquest, in which a group of people called Normans, who inhabited Nor...
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[ "https://en.wikipedia.org/wiki/List_of_French_expressions_in_English" ]
[ [] ]
1k4ltg
Could we use magnetism as opposed to rocketry to launch objects/people/spaceships into orbit?
Could we realistically launch ourselves into space or deliver supplies to the international space station or some other orbital structure via magnetism? For example could I have an electro magnet on the ground at a launch site, a package that needs to go into space attached to a magnet or inside an electro magnetic c...
askscience
http://www.reddit.com/r/askscience/comments/1k4ltg/could_we_use_magnetism_as_opposed_to_rocketry_to/
{ "a_id": [ "cblboq0", "cbldrfb" ], "score": [ 3, 2 ], "text": [ "People talk about doing something like this: \n\nThe mass driver, which is similar to some designs for high-speed trains.\n\n_URL_0_\n\nIn most cases it's not practical to launch from Earth's surface to orbit with one of...
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[ "http://www.kjmagnetics.com/proddetail.asp?prod=LEV2" ]
[ [ "http://en.wikipedia.org/wiki/Mass_driver" ], [] ]
2hgrt0
why are there so many contradictory ideas about what humans should be eating, but other animals are very straightforward in knowing what to eat?
explainlikeimfive
http://www.reddit.com/r/explainlikeimfive/comments/2hgrt0/eli5_why_are_there_so_many_contradictory_ideas/
{ "a_id": [ "ckshy9a", "cksi1gt", "cksice0", "ckskpxc" ], "score": [ 4, 10, 5, 4 ], "text": [ "The eternal battle of scientific evidence vs. \"common sense\" dieting vs. weight loss vs. ethical diets", "We have the technology to make whatever we want and the resources t...
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[ [], [], [], [] ]
7z0rzd
In the 1920s, what did people feel nostalgia towards?
AskHistorians
https://www.reddit.com/r/AskHistorians/comments/7z0rzd/in_the_1920s_what_did_people_feel_nostalgia/
{ "a_id": [ "dum1m8f" ], "score": [ 3 ], "text": [ "This is not to prevent anyone from writing you a full, new answer, but you may be interested in these two answers of mine:\n\n[Why are people today fascinated with the Victorian era?](_URL_0_)\n\n[Dang kids! Or: Why does each generation have such...
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[ [ "https://www.reddit.com/r/AskHistorians/comments/7brmla/why_are_people_today_fascinated_with_the/dpl8k1o/", "https://www.reddit.com/r/AskHistorians/comments/5zavf4/dang_kids_or_why_does_each_generation_have_such/dex8q7t/" ] ]
bvj7a1
The USA had a large percentage of German immigrants in the early 20th century. What was life like for them during WWI and WWII? Did many serve the Allies or did any go back to the “Fatherland”? Also why did the US sell to the British and not the Germans before they entered both wars?
Other questions that would be interesting are: How did the government convince German immigrants that their new country was going to war with their homeland? Was there any camps? Like the Japanese after Pearl Harbour. Was there any German related Terrorism on US soil? How did non-German citizens treat them? ...
AskHistorians
https://www.reddit.com/r/AskHistorians/comments/bvj7a1/the_usa_had_a_large_percentage_of_german/
{ "a_id": [ "eprt9u0" ], "score": [ 3 ], "text": [ "One of the first things you need to think about is why the Germans came over to the US. The vast majority of immigrants came after the failed Democratic revolutions in the 1890s, so they wanted to live in Republican state. That being said while t...
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1ashx2
Does brushing your tongue harm your taste buds?
askscience
http://www.reddit.com/r/askscience/comments/1ashx2/does_brushing_your_tongue_harm_your_taste_buds/
{ "a_id": [ "c90f4ik", "c90f6w7" ], "score": [ 20, 881 ], "text": [ "In actuality it may improve taste perception.\n\n_URL_1_\n\nHowever, it may be different for some tastes vs. others (e.g., NaCl vs. citric).\n\n[1](_URL_0_)\n\n[2](_URL_2_)", "Dentist here.\n\nTo answer your question ...
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[ [ "http://onlinelibrary.wiley.com/doi/10.1034/j.1601-5037.2003.00034.x/full", "http://onlinelibrary.wiley.com/doi/10.1111/j.0303-6979.2004.00507.x/full", "http://www.ncbi.nlm.nih.gov/pubmed/264535?systemMessage=Pay+Per+View+will+be+unavailable+for+upto+3+hours+from+06%3A00+EST+March+23rd+on+Wiley+Online...
2vgfo9
if redbull lost a lawsuit over their "gives you wings" slogan, how do the current commercials still include the slogan without a small disclaimer included?
explainlikeimfive
http://www.reddit.com/r/explainlikeimfive/comments/2vgfo9/eli5_if_redbull_lost_a_lawsuit_over_their_gives/
{ "a_id": [ "cohdw1w", "cohh7k2" ], "score": [ 153, 12 ], "text": [ "Actually, that law suit (for $13.5 million) was not because of the tagline \"give you wings\" (which is clearly understood as humor).\n\nThe law suit was over the fact that Red Bull oversold the drink's ability to improve...
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[ [], [] ]
2161cr
What gods were foreign and then adopted by the Greeks and Romans through trade/war/etc?
AskHistorians
http://www.reddit.com/r/AskHistorians/comments/2161cr/what_gods_were_foreign_and_then_adopted_by_the/
{ "a_id": [ "cga1661" ], "score": [ 7 ], "text": [ "A few of the most famous examples of Roman religious syncretism are the cults of Isis, Mithras, and Sulis.\n\nIsis was an Egyptian goddess of magic and mother of Horus, God of the Pharaoh. She was an incredibly important figure in the Egyptian pa...
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[ [] ]
7vuiz1
If the salt water in the ocean accumulated over time was there ever a point where it was all freshwater?
askscience
https://www.reddit.com/r/askscience/comments/7vuiz1/if_the_salt_water_in_the_ocean_accumulated_over/
{ "a_id": [ "dtvufaw" ], "score": [ 3 ], "text": [ "Perhaps briefly (on a geological timescale), when the atmosphere cooled enough for the first rains to fall, the resultant bodies of water may have been pure enough to be considered freshwater with less than 500ppm of dissolved salts. There were ...
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[ [] ]
5adr0l
why does adding salt to desserts make them seemingly sweeter?
explainlikeimfive
https://www.reddit.com/r/explainlikeimfive/comments/5adr0l/eli5_why_does_adding_salt_to_desserts_make_them/
{ "a_id": [ "d9foe5g", "d9foi7z" ], "score": [ 6, 6 ], "text": [ "Salt changes the electrochemical reactions that happen in the chemoreceptors on your tongue (taste buds). The effect is different for different types of receptors; bitter receptors are inhibited, while sweet receptors have t...
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[ [], [] ]
rtxs2
why did a law need to be passed telling federal employees that they couldn't participate in insider trading?
I know Obama just signed a law saying congresspeople couldn't participate in insider trading-- were they exempt from the other laws against it?
explainlikeimfive
http://www.reddit.com/r/explainlikeimfive/comments/rtxs2/eli5_why_did_a_law_need_to_be_passed_telling/
{ "a_id": [ "c48nfh8" ], "score": [ 6 ], "text": [ "This is how I understand it. Can someone please fill in the details or correct me on this?\n\nPart of the reason is because, technically, a lot of what they were doing wasn't \"insider\" trading. Typically, insider trading happens (e.g.) when y...
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[ [] ]
2ci7me
the future of computer storage: storage capacity vs compression abilities
So we're seeing increasing sizes of HDDs and memory sticks, but I'm wondering if the sizes will just continue to increase, so that in 5-10 years, will we have 1tb mini usb sticks (sure, they probably allready exist, but they arent cheap yet, like the 16gb ones...) OR will we see more progress in compression and things ...
explainlikeimfive
http://www.reddit.com/r/explainlikeimfive/comments/2ci7me/eli5_the_future_of_computer_storage_storage/
{ "a_id": [ "cjfqnqt", "cjfvn4c" ], "score": [ 4, 5 ], "text": [ "There is a mathematical limit to how much data can be compressed, and there's an entire field of math (called Information Theory) dedicated to studying it.", "So far, capacity has kept increasing rapidly. You used to buy...
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[ [], [] ]
1939xi
Can a satellite maintain an orbit forever under ideal conditions?
Intuitively I feel like any satellite orbiting another body will eventually either collide or escape orbit, and I also think this is an application of the second law of thermodynamics. If this is right, what mechanics would be involved in the gradual decay of an orbit? And if I'm wrong, why wouldn't this be considered ...
askscience
http://www.reddit.com/r/askscience/comments/1939xi/can_a_satellite_maintain_an_orbit_forever_under/
{ "a_id": [ "c8ke8op", "c8kenq9" ], "score": [ 14, 3 ], "text": [ "Purely from Newtonian gravity - i.e., the gravity you learn about in high school - there's no decay under ideal conditions. But we've known that picture of gravity is wrong for nearly a century. The more modern theory, Eins...
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[]
[ [ "http://en.wikipedia.org/wiki/Hulse%E2%80%93Taylor_binary" ], [] ]
40xh43
Do satellites travel with the rotation of the earth or against and if they go both ways would two identical satellites going opposite directions at the same altitude have to travel at different speeds to maintain orbit?
askscience
https://www.reddit.com/r/askscience/comments/40xh43/do_satellites_travel_with_the_rotation_of_the/
{ "a_id": [ "cyxxlmy", "cyy3xrs", "cyy3zpt", "cyy44n5", "cyy7cr9", "cyy9z2h", "cyywhkp" ], "score": [ 218, 13, 21, 11, 3, 3, 2 ], "text": [ "Most satellites are in prograde orbits, meaning that they orbit in the same direction that the earth rotates....
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[]
[ [ "https://en.wikipedia.org/wiki/Artificial_satellites_in_retrograde_orbit", "http://www.britannica.com/topic/Shavit" ], [ "https://i.ytimg.com/vi/Wjl8FRPqnfA/hqdefault.jpg", "https://upload.wikimedia.org/wikipedia/commons/d/d0/Lagrangian_points_equipotential.gif" ], [ "https://en.wikipe...
fj8vo
Scientists: What is the coolest thing you've learned in your field?
I'm a budding scientist and have an interest in so many different fields. So I'd love to know: What have you learned in your field that is the coolest or most eloquent or just something where you had to stop and say wow, that totally changes how I see ____.
askscience
http://www.reddit.com/r/askscience/comments/fj8vo/scientists_what_is_the_coolest_thing_youve/
{ "a_id": [ "c1gc1ax", "c1gc6at", "c1gc6bf", "c1gc89b", "c1gcqhz", "c1gcr23", "c1gczy7", "c1gdrcv", "c1gdsq9", "c1gdxlb" ], "score": [ 5, 13, 3, 7, 2, 2, 7, 2, 7, 3 ], "text": [ "I suppose one of the cool things would be [retr...
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[ [ "http://en.wikipedia.org/wiki/Retrotransposon" ], [ "http://www.youtube.com/watch?v=Mszlckmc4Hw" ], [], [], [ "http://en.wikipedia.org/wiki/Magneto-optical_trap" ], [ "http://www.mpa-garching.mpg.de/galform/virgo/millennium/" ], [ "http://en.wikipedia.org/wiki/Noether's_the...
2n2dzk
why is vibrato singing considered good?
I hear a lot of professional singers (mainly female) who all sing with very prominent vibrato. To me this feels like they just can't hold a solid note.
explainlikeimfive
http://www.reddit.com/r/explainlikeimfive/comments/2n2dzk/eli5_why_is_vibrato_singing_considered_good/
{ "a_id": [ "cm9ph3b", "cm9phb6" ], "score": [ 2, 6 ], "text": [ "It's a very difficult skill to learn well, and much much harder than holding a steady pitch, at least to do it with smooth even control. Having said that it's an aesthetic choice, people do it because they like it, and becau...
[]
[]
[ [], [] ]
bf5epa
Was every desert once a body of water?
[deleted]
askscience
https://www.reddit.com/r/askscience/comments/bf5epa/was_every_desert_once_a_body_of_water/
{ "a_id": [ "elbajxd", "elc0ksi" ], "score": [ 12, 6 ], "text": [ "It's hard to say definitively whether or not every desert was once under a body of water, but desertification of once arable land is possible with poor land management, such as what happened with Africa after the Romans cut...
[]
[]
[ [], [ "http://www.johntyman.com/sahara/s014.jpg" ] ]
1txwua
What happens to gut flora if a person is dying of starvation or dehydration?
askscience
http://www.reddit.com/r/askscience/comments/1txwua/what_happens_to_gut_flora_if_a_person_is_dying_of/
{ "a_id": [ "ceclcbu", "cecyta2" ], "score": [ 11, 8 ], "text": [ "Depending on where in the gut you're looking at, it may change. During starvation, your stomach acid may become more concentrated, and stronger - thus a small amount of bacteria in the proximal duodenum (small bowel coming ...
[]
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[ [], [] ]
5tjo00
how were length/liquid measurements kept the same everywhere?
As in, if this is right: _URL_0_ How did they keep the length of an inch the same everywhere, if they didn't have the exact same 3 pieces of barley nor was a man's belt the same to determine every yard. Or how did they keep the measurement of a pint the same every place. How would they even create an exact container...
explainlikeimfive
https://www.reddit.com/r/explainlikeimfive/comments/5tjo00/eli5_how_were_lengthliquid_measurements_kept_the/
{ "a_id": [ "ddn0wgy" ], "score": [ 3 ], "text": [ "The short answer was, they didn't. Standards varied heavily from region to region. Keep in mind, back then, travel/trade was *a lot* harder, so the effects were much less noticeable.\n\nIn some cases, once things were more developed, they would h...
[]
[ "http://www.factmonster.com/ipka/A0769529.html" ]
[ [] ]
11dniw
Why can't you tame a Zebra?
I read the following quote from [this comment](_URL_0_): "I think Zebras are one of the only animals Biologists and Zoologists claim can never be domesticated or tamed." Then I did some google searching and found that there was quite a lot of layman's speculation that this was true. So, **Why can't you tame a zebra?...
askscience
http://www.reddit.com/r/askscience/comments/11dniw/why_cant_you_tame_a_zebra/
{ "a_id": [ "c6loyf0" ], "score": [ 2 ], "text": [ "\"Taming\" isn't all-or-nothing. There's a range of behaviors that includes whether the animal attacks humans, runs away from humans, tolerates being touched, tolerates various medical examinations and procedures, responds to commands, actively s...
[]
[ "http://www.reddit.com/r/pics/comments/11d6xg/this_guy_found_two_grizzly_cubs_with_their_dead/c6lhd94" ]
[ [] ]
1kj2fe
Is the earths ozone layer capable of changing position?
For instance, if China has a larger impact on the ozone layer and creates bigger holes above their cities, is it possible for these holes to move and affect some other less polluting zones like Europe?
askscience
http://www.reddit.com/r/askscience/comments/1kj2fe/is_the_earths_ozone_layer_capable_of_changing/
{ "a_id": [ "cbpibdh", "cbps0ki" ], "score": [ 2, 3 ], "text": [ "Yes. The ozone holes are generally around the poles and move around over time. There are some lovely maps here showing changes over time _URL_0_", "Well, the ozone layer is ubiquitous through the stratosphere. In fact,...
[]
[]
[ [ "http://chiefio.wordpress.com/2011/04/04/ozone-hole-swaps-pole/" ], [] ]
272e3x
how does paypal make money/stay in business?
explainlikeimfive
http://www.reddit.com/r/explainlikeimfive/comments/272e3x/eli5_how_does_paypal_make_moneystay_in_business/
{ "a_id": [ "chwpwme", "chwpxum", "chwrd67", "chwrfuv" ], "score": [ 2, 6, 2, 2 ], "text": [ "If you sell something on Paypal, you have to pay a certain percentage of the transaction to Paypal.", "If you are a merchant selling something through them they take a 2.9% + $...
[]
[]
[ [], [], [], [] ]
2hjs2e
Three questions about the Napoleonic army.
I'm curious and want answers for some questions. 1- How often did officers wives accompanied them, was it allowed? 2- In what sort of accommodation did the officers have during campaigns? 3- Did infantry commanding officers ride horses? Edit: Removed unnecessary word
AskHistorians
http://www.reddit.com/r/AskHistorians/comments/2hjs2e/three_questions_about_the_napoleonic_army/
{ "a_id": [ "cktcpzi" ], "score": [ 6 ], "text": [ "During a campaign, an officer was generally allowed a small Wagon to carry personal effects and anything necessary for his work in the field. This would range from a tent and necessary notes to liquor and personal reading. Naturally the higher th...
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[ [] ]
37vtaa
What people does the Assyrians descend from?
To my knowledge Assyrians are the descendants of the Akkadians and share linguistic, cultural, geographical and many more connections. Could historians elaborate further on this and more in depth? Question regarding both ancient and modern day Assyrians. Modern day Assyrians being descendants of Ancient Assyrians and...
AskHistorians
http://www.reddit.com/r/AskHistorians/comments/37vtaa/what_people_does_the_assyrians_descend_from/
{ "a_id": [ "crqhqtz", "crr38fl" ], "score": [ 4, 2 ], "text": [ "This is a somewhat controversial topic within the Syriac christian community. Basically there are two main schools of thought: those who identify as Assyrians and descendants from the ancient Assyrians and those who identify...
[]
[]
[ [], [ "http://www.reddit.com/r/AskHistorians/comments/2u5p7f/is_there_a_difference_between_assyrian_and_syriac/", "http://www.reddit.com/r/AskHistorians/comments/2zcvnq/what_is_the_history_of_the_arameans_when_was/", "http://www.reddit.com/r/AskHistorians/comments/10qocs/were_the_assyrians_victim_to_a...
3p0myn
you know how you can tense up certain muscles in your foot or leg and pretty immediately give yourself a cramp? why do your muscles have those 'pressure points' or non-random cramp areas, and why is it so easy to bring about a cramp in them?
It seems like parts of my body are on a hair trigger, waiting for me to make that one right move, and lock up.
explainlikeimfive
https://www.reddit.com/r/explainlikeimfive/comments/3p0myn/eli5_you_know_how_you_can_tense_up_certain/
{ "a_id": [ "cw27b8b" ], "score": [ 2 ], "text": [ "I tried to read up on this, and also asked my doctor about it, and it seems to not be totally known, in part because there can be a lot of different reasons depending on the person and circumstances.\n\nI think these are usually technically muscl...
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[ [ "http://www.wikihow.com/Treat-Muscle-Spasms" ] ]
2oqb4i
how can the hubble space telescope keep its lens pointed in the same spot to take long exposure shots when it's orbiting the earth every 97 minutes?
explainlikeimfive
http://www.reddit.com/r/explainlikeimfive/comments/2oqb4i/eli5_how_can_the_hubble_space_telescope_keep_its/
{ "a_id": [ "cmpiou3", "cmpivi3", "cmpjs8e", "cmpkqpo", "cmpniic", "cmpzi4o" ], "score": [ 6, 27, 11, 164, 8, 2 ], "text": [ "It does not take a continuous exposure but rather multiple exposures that are then stitched together.", "Don't forget that while...
[]
[]
[ [], [], [], [], [ "http://en.wikipedia.org/wiki/Hubble_Deep_Field" ], [] ]
8w9efx
what do fireworks event companies do the rest of the year? how do they stay profitable?
explainlikeimfive
https://www.reddit.com/r/explainlikeimfive/comments/8w9efx/eli5_what_do_fireworks_event_companies_do_the/
{ "a_id": [ "e1tq7od" ], "score": [ 6 ], "text": [ "Sporting events mostly. A lot of minor league baseball teams have displays at the end of weekend games. Same with other sports as well. " ] }
[]
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[ [] ]
212jnf
Why didn't land animals evolve to dinosaur size again after their extinction?
askscience
http://www.reddit.com/r/askscience/comments/212jnf/why_didnt_land_animals_evolve_to_dinosaur_size/
{ "a_id": [ "cg92153", "cg92bwb", "cg92otk", "cg93avj", "cg9oxyn" ], "score": [ 73, 15, 2, 185, 2 ], "text": [ "Until the end of the last ice age (10-12,000 years ago ish), there were a lot of really, really large mammals. Things like mammoths, mastodons, giant grou...
[]
[]
[ [ "http://www.plosone.org/article/fetchObject.action?uri=info%3Adoi%2F10.1371%2Fjournal.pone.0051925&representation=PDF" ], [ "http://www.plosone.org/article/info%3Adoi%2F10.1371%2Fjournal.pone.0078573", "http://www.ncbi.nlm.nih.gov/pmc/articles/PMC1691423/pdf/12965005.pdf" ], [], [ "h...
emhktu
what is computer science?
explainlikeimfive
https://www.reddit.com/r/explainlikeimfive/comments/emhktu/eli5_what_is_computer_science/
{ "a_id": [ "fdosbmw", "fdov4qi" ], "score": [ 3, 4 ], "text": [ "When computers were first built and people came to realize how powerful they were, they needed people to figure out how to make them work and how to make them better. The original designers tended to be mathematicians, physi...
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[]
[ [], [] ]
2sexww
What defines the maximum and minimum wavelength of electromagnetic radiation?
Basically, I know Gamma Rays are the shortest wavelength of light, but is there a limit to how short they can be? And what creates that limit. Alternatively, is it possible for a wavelength to be so long that it is essentially a straight line?
askscience
http://www.reddit.com/r/askscience/comments/2sexww/what_defines_the_maximum_and_minimum_wavelength/
{ "a_id": [ "cnosoqu" ], "score": [ 5 ], "text": [ "There is no maximum or minimum wavelength, any wavelength can be transformed into another one with the right choice of reference frame. A possible exception to this is if quantum gravity breaks Lorentz symmetry, and then there will be some minimu...
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[]
[ [] ]
1ciok3
when i wake up at 3 am to pee, why does keeping my eyes closed for my trip to the bathroom seem to help me get back to sleep faster?
explainlikeimfive
http://www.reddit.com/r/explainlikeimfive/comments/1ciok3/eli5_when_i_wake_up_at_3_am_to_pee_why_does/
{ "a_id": [ "c9gvaxd" ], "score": [ 2 ], "text": [ "Your brain has this thing called a circadian rhythm. What it's designed to do is make you sleepy at night time and wakeful during the day. Unfortunately, your body doesn't have a clock inside of it so it has to rely on cues outside of you to know...
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[]
[ [] ]
chkj73
When a hot surface (a grill) is radiating hot air, why is there distortion in the air above it?
Possibly wrong flair, my bad in advance. My thought is that since the air above the grill is so hot, the particles are moving so fast that the bump the photons around, causing that wavy heat distortion I see.
askscience
https://www.reddit.com/r/askscience/comments/chkj73/when_a_hot_surface_a_grill_is_radiating_hot_air/
{ "a_id": [ "euxj53f" ], "score": [ 8 ], "text": [ "The angle at which air refracts light changes based on density. There is a temperature and density gradient between the hot grill and relatively cool surrounding air." ] }
[]
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[ [] ]
2lzuhp
Is there any evidence that essential oils actually do anything other than smell good?
askscience
http://www.reddit.com/r/askscience/comments/2lzuhp/is_there_any_evidence_that_essential_oils/
{ "a_id": [ "clzp7s9", "clzp9it", "cm03435" ], "score": [ 18, 7, 6 ], "text": [ "Essential oil simple means that is possess a smell similar to the plant it is derived from. It isn't based on anything medical related. Now that doesn't mean that they arn't good for you, it just means...
[]
[]
[ [], [ "http://www.ncbi.nlm.nih.gov/pubmed/20487577", "http://www.ncbi.nlm.nih.gov/pubmed/15555788" ], [] ]
1ilapa
how do they move sculptures that are to big for trucks?
Phone won't let me do just a title, pay no attention to this. Edit: ah dicks, forgot ELI5
explainlikeimfive
http://www.reddit.com/r/explainlikeimfive/comments/1ilapa/how_do_they_move_sculptures_that_are_to_big_for/
{ "a_id": [ "cb5jqa0" ], "score": [ 2 ], "text": [ " > Edit: ah dicks, forgot ELI5\n\nHa. It's ok. It's still evident this is a legit ELI5 question.\n\nI really wish there were a better answer, but they pretty much just [close down all the roads](_URL_0_). It's super inconvenient (which is why th...
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[ [ "http://laughingsquid.com/340-ton-boulder-enroute-to-los-angeles-museum-for-giant-sculpture/" ] ]
1ds2eg
Does "alcoholism" or "alcoholic" have a scientific definition, or is it a more subjective term?
askscience
http://www.reddit.com/r/askscience/comments/1ds2eg/does_alcoholism_or_alcoholic_have_a_scientific/
{ "a_id": [ "c9tb72x", "c9tb9m7" ], "score": [ 2, 2 ], "text": [ "The DSM-IV-TR has definitions for alcohol abuse and alcohol dependence - [link](_URL_0_).\n\nIt's important to note that (a) The DSM V is due very shortly and (b) There are many researchers who feel that the DSM does not use...
[]
[]
[ [ "http://www.ncbi.nlm.nih.gov/books/NBK44358/" ], [] ]
3jqxct
how can an aircrafts engine work at such high altitudes where humans struggle to breathe due to lack of oxygen?
explainlikeimfive
https://www.reddit.com/r/explainlikeimfive/comments/3jqxct/eli5how_can_an_aircrafts_engine_work_at_such_high/
{ "a_id": [ "curiq8n", "curk724" ], "score": [ 3, 2 ], "text": [ "The aircraft require less power at high altitude because of less air resistance but very few aircraft can operate at very high levels due to the lack of air.", "The plane does indeed need a *lot* of oxygen from the air. ...
[]
[]
[ [], [] ]
12y9hz
What are the heat related consequences of urination?
Does urination increase, decrease, or not affect body temperature?
askscience
http://www.reddit.com/r/askscience/comments/12y9hz/what_are_the_heat_related_consequences_of/
{ "a_id": [ "c6z5bl2" ], "score": [ 3 ], "text": [ "When urine leaves your body it is body temperature. Your body either heats, or is heated, by the cold or hot food and liquids you eat. Urinating itself does not change your body temperature as you are evacuating this temperature stabilized liquid...
[]
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[ [] ]
43zrok
why does the western world (say usa and western europe) get involved in armed local conflicts all over the world even if it doesn't have to?
explainlikeimfive
https://www.reddit.com/r/explainlikeimfive/comments/43zrok/eli5_why_does_the_western_world_say_usa_and/
{ "a_id": [ "czm7imm", "czm7kje", "czm7pbt", "czm9i01", "czmc0ie", "czmc505", "czmcgxh", "czmcl9d", "czmd9l1", "czmdcw6", "czmez39", "czmf3hy", "czmf87k", "czmfi09" ], "score": [ 20, 35, 347, 6, 2, 30, 11, 5, 6, 5, ...
[]
[]
[ [], [], [], [], [], [], [], [], [ "https://en.wikipedia.org/wiki/Hegemonic_stability_theory" ], [], [], [], [], [] ]
2bk49m
What portion of the world's current gold supply was part of Atahualpa's ransom?
AskHistorians
http://www.reddit.com/r/AskHistorians/comments/2bk49m/what_portion_of_the_worlds_current_gold_supply/
{ "a_id": [ "cj6gc6b", "cj6gihl" ], "score": [ 18, 9 ], "text": [ "Let's assume that Hernando Pizarro was telling the truth about the size of the ransom and that all the promised ransom was received. Here is the description from Hernando Pizarro \n\n > for that he could give them ten th...
[]
[]
[ [ "http://greenanswers.com/question/how-much-gold-circulation-world/", "http://upload.wikimedia.org/wikipedia/commons/5/57/Silver_plates_and_gold_beaker,_Peru,_Chimu_and_Inca_-_Staatliches_Museum_f%C3%BCr_V%C3%B6lkerkunde_M%C3%BCnchen_-_DSC08503.JPG", "http://www.shsu.edu/~his_ncp/Pizarro.html", "ht...
3gisma
Why was the practice of presenting men, who refused to enlist in the army, a white feather supported by early feminist organizations?
I guess I'm mostly thinking about England during WWI. It doesn't seem to be very inline with their other causes of universal suffragism.
AskHistorians
http://www.reddit.com/r/AskHistorians/comments/3gisma/why_was_the_practice_of_presenting_men_who/
{ "a_id": [ "ctyk9m5" ], "score": [ 3 ], "text": [ "The so-called 'Order of the White Feather' was created in Britain in 1914 by a former admiral, and essentially involved handing out 'white feathers' to anyone, specifically men, not seen as supporting the war effort, ie not enlisting. Some Britis...
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[]
[ [ "https://www.youtube.com/watch?v=ziGow3CLalo", "https://www.youtube.com/watch?v=5W0657Bwn_A" ] ]
525hgl
In the Byzantine Empire, what type of names did people have?
I'm curious, I know that the Byzantine Empire is also referred to as the Eastern Roman Empire so I'm curious as to what type of names people had. \*EDIT* Forgot to include what time period I'm talking about in the title. I'm asking about what names they used in the 13th century.
AskHistorians
https://www.reddit.com/r/AskHistorians/comments/525hgl/in_the_byzantine_empire_what_type_of_names_did/
{ "a_id": [ "d7hk088", "d7hm99g", "d7jdwvo" ], "score": [ 3, 25, 2 ], "text": [ "Follow up, when did the Byzantines stop using Latin and changed to more Greek names?", "That depends on the time period and location. Up until around the sixth century, you can see a lot of empero...
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[ [], [], [] ]
3pvk0y
To what extent did the Soviet-Polish war cause Poland to be successfully invaded in 1939?
Did it weaken Poland so it could not win another fight?
AskHistorians
https://www.reddit.com/r/AskHistorians/comments/3pvk0y/to_what_extent_did_the_sovietpolish_war_cause/
{ "a_id": [ "cw9utx8" ], "score": [ 5 ], "text": [ "The Polish army was strong for a country of its economical development - it was well trained and equipped with modern arms. However, they were unable to stand up to the full power of a grand power such as Germany, and even less the power of two g...
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[ [] ]
97l9hr
why is perpetual energy from gravity impossible?
explainlikeimfive
https://www.reddit.com/r/explainlikeimfive/comments/97l9hr/eli5_why_is_perpetual_energy_from_gravity/
{ "a_id": [ "e490xd5", "e49224s" ], "score": [ 7, 3 ], "text": [ "Gravity pulls things down. You can exploit this for energy, but only once.\n\nOnce the object has exhausted its \"gravitational potential\" (i.e. hit the ground) you can't extract any more without first picking it up again....
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[ [], [] ]