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78rxt2
why can our ears handle the pressure from water or air just fine, but excessive loud noise can cause damage?
explainlikeimfive
https://www.reddit.com/r/explainlikeimfive/comments/78rxt2/eli5_why_can_our_ears_handle_the_pressure_from/
{ "a_id": [ "dow7nce", "dow850f", "dowrxyn" ], "score": [ 13, 3, 2 ], "text": [ "There's a difference between damaging your ears, and damaging your hearing. \n\nYour ears, or more specifically your eardrums, can be damaged by air or water pressure. You may have experienced ear pain...
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[ [], [], [] ]
7uvhe1
What happens when wearing coloured glasses, over time?
If a person were to wear, say, orange coloured glasses, continually, would their perception adapt and start 'seeing' white as white again, after a period? (Similar to wearing glasses that invert the image)
askscience
https://www.reddit.com/r/askscience/comments/7uvhe1/what_happens_when_wearing_coloured_glasses_over/
{ "a_id": [ "dtnzgd8" ], "score": [ 4 ], "text": [ "Our eyes already do this, and they do it instantly. We're able to adapt quite well to changing light conditions throughout the day and night, accurately identifying colors and such. It's actually a great frustration for photography that our dumb ...
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[ [] ]
83pf7j
Early modern opinions on the Anglo-Saxons.
I'm writing an essay on the historiography of the Adventus Saxonum and how it affected English identity over time, but I'm having trouble finding sources on/from the early modern period (in this case I mean roughly 1500-1900). I'm specifically looking for works by English historians, but I'm willing to look further abr...
AskHistorians
https://www.reddit.com/r/AskHistorians/comments/83pf7j/early_modern_opinions_on_the_anglosaxons/
{ "a_id": [ "dvjqv1s" ], "score": [ 4 ], "text": [ "Have you looked at John Niles' book *The Idea of Anglo-Saxon England 1066–1901: Remembering, Forgetting, Deciphering,\nand Renewing the Past*? At least the chapters I've read (admittedly not all of them), it's a good guide to who was talking abou...
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[ [] ]
as4jjt
why do people ask to be roasted?
explainlikeimfive
https://www.reddit.com/r/explainlikeimfive/comments/as4jjt/eli5_why_do_people_ask_to_be_roasted/
{ "a_id": [ "egrplcd", "egrps9j" ], "score": [ 2, 2 ], "text": [ "Because they don't really care about getting insulted and they don't really find them as offensive.", "I think the majority of them just have a really good sense of humour and maybe know there is something about them tha...
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[ [], [] ]
6rhg7r
why is it that you are 100x more excited when a song you love comes on the radio than when you select it from your personalized music list?
explainlikeimfive
https://www.reddit.com/r/explainlikeimfive/comments/6rhg7r/eli5_why_is_it_that_you_are_100x_more_excited/
{ "a_id": [ "dl528k5" ], "score": [ 4 ], "text": [ "Because the chances of it being selected randomly in radio tends to be less than you selecting it yourself. It's like winning the lottery for $5 rather than a friend giving you $5. You feel luckier" ] }
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[ [] ]
89ny4v
if i jump out of an airplane at cruising altitude into the ocean, how deep would i plunge, and would i be able to resurface before running out of air?
explainlikeimfive
https://www.reddit.com/r/explainlikeimfive/comments/89ny4v/eli5_if_i_jump_out_of_an_airplane_at_cruising/
{ "a_id": [ "dws8rlm", "dws8tho", "dws8vdw", "dws9bl9", "dws9ekx" ], "score": [ 2, 2, 2, 2, 2 ], "text": [ "The surface tension of the water would kill you. You wouldn't need to worry about any of the rest of your questions. ", "You would die instantly. Water on...
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[ [], [], [], [], [] ]
270i4n
why are tobacco and alcohol companies exempt from listing ingredients on their products?
Obvious answers probably include: 1. They want to keep their ingredients secret between different companies. 2. They know listing some of the ingredients would probably deter some consumers. 3. They have such a powerful influence on the government that, because of 1. and 2., they want and are able to lobby against it....
explainlikeimfive
http://www.reddit.com/r/explainlikeimfive/comments/270i4n/eli5_why_are_tobacco_and_alcohol_companies_exempt/
{ "a_id": [ "chw88es", "chw8nba" ], "score": [ 3, 8 ], "text": [ "I think they do post that information. They just don't have to post the exact formula to prevent their competition from getting their \"recipe\".", "Alcohol and tobacco are under the regulation of the ATF while the FDA g...
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[ [], [] ]
enxsco
how does an amputees skin form around when it gets cut off? is it like a hole there?
Is it patched up with stitches? Does it do that right after sirgery? I was looking at Shaquem Griffin and its like a kbib at the end of his left arm. How does it form like that? Is there skin problems associated with it?
explainlikeimfive
https://www.reddit.com/r/explainlikeimfive/comments/enxsco/eli5_how_does_an_amputees_skin_form_around_when/
{ "a_id": [ "fe66xnf" ], "score": [ 8 ], "text": [ "The skin is pulled back and it's cut clean through while in a tourniquet. The bone is rounded off to prevent sharp edges. Arteries and veins are coterized, then the skin is pulled over the wound and stitched shut. There's usually enough skin to c...
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6slt1g
How did the Romans choose the seat of provincial administration centers? What were the parameters taken into account? How did those considerations change over time?
AskHistorians
https://www.reddit.com/r/AskHistorians/comments/6slt1g/how_did_the_romans_choose_the_seat_of_provincial/
{ "a_id": [ "dldubik" ], "score": [ 5 ], "text": [ "The obvious question to ask here is what provincial centers and when? The first Roman provinces were secured in the third century BC, and provincial administration lasted through to the Roman retreat to Italy and the east--if we consider the Byza...
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[ [] ]
4jr8ig
Why did the U.S. and USSR have some many targets on nuclear scenarios during the Cold War?
I understand the idea that industrial centres were targets to cripple the enemies economy and military targets were obviously targeted to prevent any meaningful counter-attack. But why were so many targets population centres?
AskHistorians
https://www.reddit.com/r/AskHistorians/comments/4jr8ig/why_did_the_us_and_ussr_have_some_many_targets_on/
{ "a_id": [ "d39iqy6" ], "score": [ 8 ], "text": [ "There are two basic strategies when it comes to strategic nuclear warfare: counter-force and counter-value.\n\n**Counter-force** aims to destroy the enemy's ability to carry out a nuclear strike or nuclear retaliation. Here, you target missile si...
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[ [] ]
ap1nea
Why are turboprops inefficient at high speeds and heights while turbo fans are?
askscience
https://www.reddit.com/r/askscience/comments/ap1nea/why_are_turboprops_inefficient_at_high_speeds_and/
{ "a_id": [ "eg5msa0", "eg6c65m" ], "score": [ 3, 3 ], "text": [ "It has to do with disk loading and local Mach number. An open fan has an elliptical loading, while a ducted fan has a linear loading. The ducted fan allows us to keep the fan tip velocity lower for the same thrust level, a...
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[ [], [ "https://en.wikipedia.org/wiki/Republic_XF-84H_Thunderscreech" ] ]
325t9u
why are movies rated pg-13, but tv shows rated tv-14 in the us? why do they increase the age by 1 for tv shows?
explainlikeimfive
http://www.reddit.com/r/explainlikeimfive/comments/325t9u/eli5_why_are_movies_rated_pg13_but_tv_shows_rated/
{ "a_id": [ "cq85uuv", "cq85xdx", "cq85z3m", "cq8ad1p" ], "score": [ 22, 4, 6, 3 ], "text": [ "The film ratings system is administered by the Motion Picture Association of America, while television content ratings are governed by the Federal Communications Committee. Other ...
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[]
[ [], [], [], [ "http://www.businessinsider.com/indiana-jones-and-the-temple-of-doom-created-pg-13-rating-2014-4" ] ]
8fbrjw
why has kim jong un had such a change of heart all of a sudden?
explainlikeimfive
https://www.reddit.com/r/explainlikeimfive/comments/8fbrjw/eli5_why_has_kim_jong_un_had_such_a_change_of/
{ "a_id": [ "dy25za6", "dy2889l", "dy28q00" ], "score": [ 2, 6, 3 ], "text": [ "I'm guessing those last couple nukes he dropped into his mountain really messed something up, probably to the point where he is gonna need some international assistance. The last few defectors have rep...
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[ [], [ "https://www.telegraph.co.uk/news/2017/10/31/collapse-north-korea-nuclear-test-site-leaves-200-dead/" ], [] ]
40bwna
Artillery tactics
Hi doing some research about artillery and have a couple of questions. How was artillery used in field battles during the 18th century, pre-Napoleon? Was there initial bombardment only, or was it used during the whole battle? What was the main aim of artillery, infantry casualties? How effective was it, was it a deci...
AskHistorians
https://www.reddit.com/r/AskHistorians/comments/40bwna/artillery_tactics/
{ "a_id": [ "cysz8tu", "cyt0k7j" ], "score": [ 5, 9 ], "text": [ "Artillery was used in a couple of ways - as a physical weapon, but also as a psychological tool at unnerving the opponent. Can you imagine marching into cannon fire, not knowing if your line was to be targeted, seeing rows o...
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[ [], [] ]
9ygknk
When and why did people start thinking that there was no or almost no science in the european Middle Ages?
Also: What is the origin of the term 'Dark Ages'?
AskHistorians
https://www.reddit.com/r/AskHistorians/comments/9ygknk/when_and_why_did_people_start_thinking_that_there/
{ "a_id": [ "ea2nnqq" ], "score": [ 17 ], "text": [ "Terrible understanding of science in the medieval period probably has multiple origins, but I want to just point out two places where bad historical ideas about medieval science were mobilized:\n\n* During the 18th-century Enlightenment, the ide...
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[ [] ]
c5cp0d
Are all the seeds a plant produces genetically identical?
askscience
https://www.reddit.com/r/askscience/comments/c5cp0d/are_all_the_seeds_a_plant_produces_genetically/
{ "a_id": [ "es15wvg", "es26odx" ], "score": [ 14, 5 ], "text": [ "No, just like all the kids you could have would be genetically different.\nAll the gametes à plant produces are different just like all you sperm cells or eggs are different.\nThus, all seeds resulting of the fertilization ...
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[ [], [] ]
562j0o
Whаt раrts оf thе brаіn аrе mоst usеd whеn lеаrnіng gоlf?
Іn mу оріnіоn іt wоuld bе thе сеrеbеllum, whісh wоuld bе usеd tо сооrdіnаtе уоur swіng аnd thе mоtоr соrtех fоr thе рrесіsе mоvеmеnts nееdеd whеn swіngіng thе сlub аnd strіkіng thе bаll, аs wеll аs thе mоvеmеnts thе bоdу mаkеs durіng thе swіng аrе thеsе twо thе mоst іmроrtаnt аrеаs оf thе brаіn usеd whеn lеаrnіng gоl...
askscience
https://www.reddit.com/r/askscience/comments/562j0o/whаt_раrts_оf_thе_brаіn_аrе_mоst_usеd_whеn/
{ "a_id": [ "d8g8pq0", "d8gaa8u", "d8gp2xi" ], "score": [ 3, 7, 2 ], "text": [ "Without wanting to be glib: _URL_0_\n\nA surfeit of papers detailing all the usual suspects: Frontal Cortex, Cortico-Striatal, Cortico-Cerebellar, Basal Ganglia, as well as a whole clutch of other areas...
[]
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[ [ "https://scholar.google.co.uk/scholar?hl=en&q=brain+activity+when+learning+golf&btnG=&as_sdt=1%2C5&as_sdtp=" ], [], [] ]
3159ii
What was the impact of Reagan's presidency on the homeless population in the United States?
I've heard a few people bring up the claim that Reagan's presidency brought about a massive influx of the mentally ill onto the streets of the US, since they were ejected from institutions due to budget cuts. Is this true?
AskHistorians
http://www.reddit.com/r/AskHistorians/comments/3159ii/what_was_the_impact_of_reagans_presidency_on_the/
{ "a_id": [ "cpyzgoa" ], "score": [ 3 ], "text": [ "So, this isn't my wheelhouse, but I was curious too. It seems from the research that Reagan's privatization of the mental healthcare community contributed somewhat, but to credit it to Reagan himself is specious at best:\n\n > \"Chief among thes...
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1i6rwx
how do modern synthesizers/keyboards work?
I understand the basics of synthesis, but as someone who isn't tech-savvy and has only played classical piano for his whole life, I find a real gap in technical jargon people use discussing keyboards. Basically, what I want to know is, how to people take the MIDI controllers/keyboards/whatever other equipment and start...
explainlikeimfive
http://www.reddit.com/r/explainlikeimfive/comments/1i6rwx/eli5_how_do_modern_synthesizerskeyboards_work/
{ "a_id": [ "cb1ikoi" ], "score": [ 3 ], "text": [ "MIDI is a moderately standardized way for different instruments/synths to talk to each other. A MIDI keyboard sends messages out saying \"using this voice number, play this note for this duration\". It may also send information like note volume a...
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[ [] ]
44nqys
why is illegal weed so expensive in the us?
Weed is legal in some states but the price ranges around 15-20$ a gram where as in some countries in Europe it is illegal, but the price is about 4$ a gram.
explainlikeimfive
https://www.reddit.com/r/explainlikeimfive/comments/44nqys/eli5_why_is_illegal_weed_so_expensive_in_the_us/
{ "a_id": [ "czrgt8h", "czrm99z", "czrs6iu", "czrxytk" ], "score": [ 10, 5, 3, 2 ], "text": [ "Much stronger enforcement leads to higher risk and lower supply. I don't know how it's enforced in and around Europe but I assume they have much more relaxed regulations and enfor...
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[ [], [], [], [] ]
5yogqd
if a joint cracking is a result of gases in the joint popping, how can i crack the same joint multiple times?
explainlikeimfive
https://www.reddit.com/r/explainlikeimfive/comments/5yogqd/eli5_if_a_joint_cracking_is_a_result_of_gases_in/
{ "a_id": [ "dero9uu", "dert6qx" ], "score": [ 2, 2 ], "text": [ "The gas doesn't go anywhere, it just comes out of solution. Over time, the gas will dissolve back into your synovial fluid. That's why you can't pop the same joint quickly, but you can after a while.", "imagine you have ...
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[ [], [] ]
3vpemt
why do the tigon and leopon have manes if the lion half was female?
[deleted]
explainlikeimfive
https://www.reddit.com/r/explainlikeimfive/comments/3vpemt/eli5_why_do_the_tigon_and_leopon_have_manes_if/
{ "a_id": [ "cxphk87" ], "score": [ 2 ], "text": [ "For the same reason that male baldness are also given by the mother's genes. Just because it is a male or female trait, that doesn't mean the genes are passed only through the same gender." ] }
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[ [] ]
1tfz5p
why are certain knives that open by spring, gravity or centrifugal force considered restricted weapons? are they somehow more dangerous than fixed blade knives?
The Criminal Code of Canada definition of a "prohibited weapon" ""prohibited weapon" means (a) a knife that has a blade that opens automatically by gravity or centrifugal force or by hand pressure applied to a button, spring or other device in or attached to the handle of the knife, or (b) any weapon, other than a fire...
explainlikeimfive
http://www.reddit.com/r/explainlikeimfive/comments/1tfz5p/eli5why_are_certain_knives_that_open_by_spring/
{ "a_id": [ "ce7j883", "ce7j8t3", "ce7jrrz" ], "score": [ 5, 2, 2 ], "text": [ "Because they are easy to conceal, they are a go-to weapon among organized crime/gangs. Making them illegal gives police the ability to investigate persons carrying them, possibly leading to further arre...
[]
[ "http://www.reddit.com/r/explainlikeimfive/comments/1bqqim/" ]
[ [], [], [] ]
p3a2a
Is capsaicin responsible for all spiciness?
Is capsaicin responsible for everything we perceive as spicy? Wasabi vs. curry, for example... the effect is notably different (nose vs. mouth).
askscience
http://www.reddit.com/r/askscience/comments/p3a2a/is_capsaicin_responsible_for_all_spiciness/
{ "a_id": [ "c3m5bqi" ], "score": [ 44 ], "text": [ "Nope, capsaicin is but one piquant. Wasabi, mustard, horseradish etc. contain [allyl isothiocyanate](_URL_0_), and black pepper has [piperine](_URL_1_)." ] }
[]
[]
[ [ "http://en.wikipedia.org/wiki/Allyl_isothiocyanate", "http://en.wikipedia.org/wiki/Piperine" ] ]
12m2o4
What chemical in toothepaste makes everything taste horrible?
askscience
http://www.reddit.com/r/askscience/comments/12m2o4/what_chemical_in_toothepaste_makes_everything/
{ "a_id": [ "c6wak1a" ], "score": [ 3 ], "text": [ "Sodium lauryl sulfate deactivates your tongues ability to taste sweet temporarily. It is synthesized from coconut and palm oils." ] }
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[ [] ]
37c3fn
how is liquid smoke made?
Seriously. Do they smoke water? Is it just chemicals? Do they grind up smoked wood and liquify it?
explainlikeimfive
http://www.reddit.com/r/explainlikeimfive/comments/37c3fn/eli5how_is_liquid_smoke_made/
{ "a_id": [ "crldro5" ], "score": [ 2 ], "text": [ "[Wikipedia](_URL_0_) tells me: You pass smoke through woodchips (which also makes it more moist) and then cool it down, at which point the smoke condenses into a liquid together with the water in the air." ] }
[]
[]
[ [ "http://en.wikipedia.org/wiki/Liquid_smoke" ] ]
f2hoia
Recommended reading for a history of gentrification
Can be in whatever country, or an international approach
AskHistorians
https://www.reddit.com/r/AskHistorians/comments/f2hoia/recommended_reading_for_a_history_of/
{ "a_id": [ "fhcxyvo" ], "score": [ 2 ], "text": [ "The best starting point would probably be the classic \"Death and Life of Great American cities\" by Jane Jacobs. It's an easy and accessible read and a good introduction. Jacobs was a key figure in the urban discourse in the 50s and 60s in New Y...
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[ [] ]
1t0p90
Is there a limit to the maximum number of radio channels we can have?
Let's take the FM band. Is there a physical limit on the number of channels you can have in it's range or given suitable technology would it be possible to subdivide the range into like a billion frequencies?
askscience
http://www.reddit.com/r/askscience/comments/1t0p90/is_there_a_limit_to_the_maximum_number_of_radio/
{ "a_id": [ "ce359rz", "ce35itp", "ce36a02", "ce370l5", "ce381pk", "ce391yj", "ce39uxx", "ce3d69o" ], "score": [ 36, 14, 3, 16, 3, 11, 3, 3 ], "text": [ "It depends how much information you want each channel to transmit, and what assumptions ...
[]
[]
[ [ "http://en.wikipedia.org/wiki/Shannon%E2%80%93Hartley_theorem" ], [ "http://en.wikipedia.org/wiki/FM_broadcast_band" ], [], [ "http://www.reddit.com/r/askscience/comments/1t0p90/is_there_a_limit_to_the_maximum_number_of_radio/ce359rz", "http://www.saecanet.com/Calculation_data/000088_000...
w2pje
Japan, Korea, and China: the evolution of three races?
I was wondering (thanks to Ceasar1313) about the origin of the Korean race- and in broader terms, of North Asia as a whole, including the Mongols, Chinese, and Japanese? I know how each country feels about their origin *culturally*, but do we have genetic proof of when and where it delineated? Thanks in advance!
AskHistorians
http://www.reddit.com/r/AskHistorians/comments/w2pje/japan_korea_and_china_the_evolution_of_three_races/
{ "a_id": [ "c59ptuz", "c59qa0r", "c59qdik", "c59yhg1" ], "score": [ 4, 10, 4, 4 ], "text": [ "I think that the current archeology findings suggest that the Asian civilization spread from the south towards north.\n\nVietnam might be the source of civilization of the Asia.\...
[]
[]
[ [], [ "http://i56.tinypic.com/21cshas.jpg" ], [], [ "http://blogs.discovermagazine.com/gnxp/2010/07/koreans-not-quite-the-purest-race/" ] ]
59ufr6
Is there any instance of an exoplanet orbiting three separate stars, or is this not even possible?
askscience
https://www.reddit.com/r/askscience/comments/59ufr6/is_there_any_instance_of_an_exoplanet_orbiting/
{ "a_id": [ "d9bizcg" ], "score": [ 10 ], "text": [ "There is [this one](_URL_0_), where the planets orbits one star in a triple system, where the other two non-planet stars are in a much closer orbit." ] }
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[]
[ [ "https://en.wikipedia.org/wiki/HD_131399_Ab" ] ]
5ogjxo
Are stars really far enough that we see them in the past? If so, are their positions and sizes different than what we see?
askscience
https://www.reddit.com/r/askscience/comments/5ogjxo/are_stars_really_far_enough_that_we_see_them_in/
{ "a_id": [ "dcjjjlm", "dcjxilq" ], "score": [ 15, 6 ], "text": [ "Yes, of course. Everything you look at is something you are seeing in the past. You're looking at your computer or phone screen right now, and that screen is a few nano light-seconds from your eyes. So the light you are see...
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[ [], [] ]
4u1th2
how do helicopter blades actually lift a 20,000 pound helicopter?
explainlikeimfive
https://www.reddit.com/r/explainlikeimfive/comments/4u1th2/eli5_how_do_helicopter_blades_actually_lift_a/
{ "a_id": [ "d5m93zg", "d5mghcq", "d5mgn3f", "d5mgs88" ], "score": [ 22, 5, 9, 2 ], "text": [ "To generate lift we use wings, which we move fast through the air. We can do this by making the vehicle go fast (planes) or by rotating the wings fast around a midpoint (helicopte...
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[ [], [], [ "http://www.rc-airplane-world.com/image-files/xrotor-blade-pitch-angle.gif.pagespeed.ic.HkBSpg9H0N.png" ], [] ]
29ysr4
what is going on with my cat when he gets 'the eyes' and goes on a rampage knocking everything over and acting like a lunatic?
explainlikeimfive
http://www.reddit.com/r/explainlikeimfive/comments/29ysr4/eli5_what_is_going_on_with_my_cat_when_he_gets/
{ "a_id": [ "ciptq5o", "ciptqbl", "cipvvon", "cipvybr", "cipw14y", "cipwsud", "cipx2ea", "cipx866", "cipxjlp", "cipyd8b" ], "score": [ 103, 34, 7, 8, 16, 3, 12, 2, 2, 2 ], "text": [ "The currently leading theory is that becaus...
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[]
[ [ "https://www.youtube.com/watch?v=l5ODwR6FPRQ" ], [], [], [], [], [], [], [], [], [] ]
2xjwzc
can someone convert from judaism and still be jewish?
I am watching a speech at the moment about the 'problem' with a rise in anti-semitasm, and I am confused on this issue. To be prejudicd against people for things they cannot choose - the country of their birth, their ethnicity or gender, and so on - is illogical and something I am dead against. However, is being Jewish...
explainlikeimfive
http://www.reddit.com/r/explainlikeimfive/comments/2xjwzc/eli5can_someone_convert_from_judaism_and_still_be/
{ "a_id": [ "cp0qs8g", "cp0qtag" ], "score": [ 4, 2 ], "text": [ "Judaism the the religion of an ethnic group, who are generally called Jewish- after their religion. It is possible to be ethnically Jewish but not a part of the Jewish faith, and vice-versa. You can be Jewish without being J...
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[ [], [] ]
2j25dh
since earth is spinning, why do we land in the same place when we jump or fall? or jumping on the bus?
explainlikeimfive
http://www.reddit.com/r/explainlikeimfive/comments/2j25dh/eli5_since_earth_is_spinning_why_do_we_land_in/
{ "a_id": [ "cl7nx4y", "cl7nx5e", "cl7ny2e", "cl7o435", "cl7ok6q", "cl7pdd0" ], "score": [ 3, 2, 2, 7, 2, 2 ], "text": [ "Because we're spinning with the Earth/moving with the bus. This is asked approximately 1 million times a day.", "Because we're spinn...
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[]
[ [], [], [], [], [ "https://www.youtube.com/watch?v=pyBNImQkRuk", "https://www.youtube.com/watch?v=053nYXFfjZE" ], [] ]
b38lzj
Do joints and cartilage grow stronger from weight training?
Specifically, do the menisci wear down or grow stronger?
askscience
https://www.reddit.com/r/askscience/comments/b38lzj/do_joints_and_cartilage_grow_stronger_from_weight/
{ "a_id": [ "ej0hjmm" ], "score": [ 2 ], "text": [ "Lifting weights strengthen muscle cells specifically, helping the joints perform better and safer as a whole. While bones and cartilage do not get \"strong\" per se, any weight-bearing exercise has been shown to help with bone density. Cartilage ...
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[ [] ]
5hbpse
I have been looking into the US tanks of WWII recently and was wondering something everyone seems to have a different answer to, how much of an upgrade was the 76 mm gun on the Sherman? Did it significantly raise the Shermans fighting ability against German Tigers and Panzer IV tanks? Also...
How did this gun fare against the Panthers later in the war?
AskHistorians
https://www.reddit.com/r/AskHistorians/comments/5hbpse/i_have_been_looking_into_the_us_tanks_of_wwii/
{ "a_id": [ "daz0ugp" ], "score": [ 7 ], "text": [ "The 75 mm gun on the Sherman was already reasonably effective against the Panzer IV and the various vehicles that were based off of it, being able to kill them at normal combat ranges. A post-war study revealed that the average distance that a US...
[]
[]
[ [ "http://www.wwiiequipment.com/pencalc/#", "http://amizaur.prv.pl/www.wargamer.org/GvA/index.html" ] ]
4hh8j6
Would a object be able to travel through the sun without evaporating if it were to be travelling fast enough?
askscience
https://www.reddit.com/r/askscience/comments/4hh8j6/would_a_object_be_able_to_travel_through_the_sun/
{ "a_id": [ "d2qp8b9" ], "score": [ 3 ], "text": [ "At some point the gain that you would get from the object moving faster (and thus being exposed to the Sun's heat for a shorter period of time) will start getting cancelled out by the fact that the higher speed itself will create heat (via fricti...
[]
[]
[ [] ]
2p72s2
i recently had the flu and i had a 102.5 degree (fahrenheit) fever but i felt cold. why does this happen and what's the reason for it?
explainlikeimfive
http://www.reddit.com/r/explainlikeimfive/comments/2p72s2/eli5_i_recently_had_the_flu_and_i_had_a_1025/
{ "a_id": [ "cmtxtly", "cmu3bge" ], "score": [ 2, 2 ], "text": [ "It's all a matter of perception.\n\nFever is your body's response to an infection, raising your internal temperature to make it more difficult for the invading virus/bacteria to thrive in your system. When your immune system...
[]
[]
[ [], [] ]
14k081
Will opening a brand new 2L pop bottle to let pressure out allow the bottle to cool faster
If I buy a brand new 2L bottle of pop and want it to get cold as fast as possible, will opening it to let pressure out make it get colder faster
askscience
http://www.reddit.com/r/askscience/comments/14k081/will_opening_a_brand_new_2l_pop_bottle_to_let/
{ "a_id": [ "c7drubb", "c7dsidy", "c7e0bwm" ], "score": [ 5, 3, 2 ], "text": [ "I assume you're thinking of the inverse relationship of pressure and temperature ala' ideal gas law?", "I would say no. It would be true if only the air that was pressurized was being depressurized....
[]
[]
[ [], [ "http://en.wikipedia.org/wiki/Bernoulli%27s_principle" ], [] ]
5x50mv
how can the economy keep growing every year if the planet has a finite amount of resources?
If every country's economy grows and is doing well won't we eventually run out of resources? Or can the economy grow without resource consumption?
explainlikeimfive
https://www.reddit.com/r/explainlikeimfive/comments/5x50mv/eli5_how_can_the_economy_keep_growing_every_year/
{ "a_id": [ "def9pns", "def9xl0", "defdq4n", "defoik5", "defq2yx", "defstdo", "defz3vq" ], "score": [ 11, 7, 2, 2, 2, 3, 8 ], "text": [ "There are types/aspects of economic growth that are unsustainable.\n\nBut not all growth is in the amount/size of...
[]
[]
[ [], [], [], [], [], [], [] ]
5zes83
why did we start using candles on birthday cakes?
I can see why cakes started being associated with birthdays but how did candles get into the mix?
explainlikeimfive
https://www.reddit.com/r/explainlikeimfive/comments/5zes83/eli5_why_did_we_start_using_candles_on_birthday/
{ "a_id": [ "dexizf3" ], "score": [ 5 ], "text": [ "Interesting question, so I decided to do some research. Here is what I found:\n\n\"Birthday cakes have been a tradition since the Ancient Romans were around, and celebrating someone’s birth with a delicious pastry seems pretty logical. But have y...
[]
[]
[ [ "mentalfloss.com" ] ]
796hvh
How small would a space object need to be before a human could jump into orbit? And to escape it’s sphere of influence?
askscience
https://www.reddit.com/r/askscience/comments/796hvh/how_small_would_a_space_object_need_to_be_before/
{ "a_id": [ "dp0fcv2" ], "score": [ 4 ], "text": [ "Once I did the math for this. It requires many assumptions, such as how high you can jump on Earth (which in turn requires not only assuming how strong your legs are but also the mass of your body), and the mass of life support equipment (that I ...
[]
[]
[ [ "http://www.exrx.net/Kinesiology/Segments.html" ] ]
n95d3
How did animals such as bees, ants, and termites evolve?
I've split this up into one simple question and one more complex **1\. Did these animals all share a common ancestor, or was it an example of convergent evolution?** **2\. How did they evolve sterile worker 'castes'?** I understand that, in bees at least, queens are made, not born, by receiving some sort of stimulu...
askscience
http://www.reddit.com/r/askscience/comments/n95d3/how_did_animals_such_as_bees_ants_and_termites/
{ "a_id": [ "c379qrf", "c379qrf" ], "score": [ 22, 22 ], "text": [ "Ants and bees are part of the same order called [hymenoptera](_URL_4_) - so no this is not an example of convergent evolution, but shared phylogenic history. This order arose sometime the triassic, some 250-200mya. Hymenop...
[]
[]
[ [ "http://en.wikipedia.org/wiki/Punctuated_equilibrium", "http://en.wikipedia.org/wiki/Bee#Solitary_and_communal_bees", "http://en.wikipedia.org/wiki/Phyletic_gradualism", "http://en.wikipedia.org/wiki/Colony_collapse_disorder", "http://en.wikipedia.org/wiki/Hymenoptera", "http://en.wikipedi...
5spi5b
how do interplanetary spacecraft (and in the future interstellar), protect against collisions with space debris?
explainlikeimfive
https://www.reddit.com/r/explainlikeimfive/comments/5spi5b/eli5how_do_interplanetary_spacecraft_and_in_the/
{ "a_id": [ "ddguq3i" ], "score": [ 3 ], "text": [ "They don't and they don't need to. Space is incredibly big and empty. Despite how visuals like the one on the [Asteroid Belt Wikipedia article](_URL_0_) makes it seem, the majority of the asteroids are very small and the distance between them is ...
[]
[]
[ [ "https://en.wikipedia.org/wiki/Asteroid_belt" ] ]
3efakb
why can't modern houses be economically independent with solar + battery+ a little backup generator just incase?
Would it add more than a fraction to a new house price?
explainlikeimfive
http://www.reddit.com/r/explainlikeimfive/comments/3efakb/eli5_why_cant_modern_houses_be_economically/
{ "a_id": [ "ctedld6", "ctedpq9", "ctge27y" ], "score": [ 3, 3, 2 ], "text": [ "You can indeed live off the grid, with no connection to the power company. This does add a fairly significant cost to the upfront price to build the home. In addition, there are maintenance and upkeep o...
[]
[]
[ [], [], [] ]
1r4yaq
Why can't i feel my intestines rub against eachother but i can feel pain in my spleen when hit there.
As title says, I feel like if I can feel the compression and pain of a livershot or spleenshot(boxing) I should also be able to feel my organs in other circumstances. If I ''vacum'' my belly in and compress my intestines and they move/rub against eachother why don't i feel that?
askscience
http://www.reddit.com/r/askscience/comments/1r4yaq/why_cant_i_feel_my_intestines_rub_against/
{ "a_id": [ "cdjxo4r" ], "score": [ 2 ], "text": [ "You feel with your sensory neurons, and the vast majority of your sensory neurons are concentrated on your skin and especially at your extremities (finger tips, toes, face). As such, there are very few sensory neurons in your internal organs, so...
[]
[]
[ [] ]
awiv7z
Did intellectual property play a role in America's gilded age? And if it did, how so and in what industries?
AskHistorians
https://www.reddit.com/r/AskHistorians/comments/awiv7z/did_intellectual_property_play_a_role_in_americas/
{ "a_id": [ "ehn00c1" ], "score": [ 7 ], "text": [ "According to Peter Andreas - absolutely. Not just the Gilded Age, but from the founding fathers' time onwards, Andreas argues, the USA has been made by illicit trade, including intellectual piracy. Alexander Hamilton \"enthousiastically encourage...
[]
[]
[ [] ]
4dvyfq
In 19th and 20th century England, if an Earl died without surviving children, could the son of his deceased elder brother's illegitimate daughter inherit?
AskHistorians
https://www.reddit.com/r/AskHistorians/comments/4dvyfq/in_19th_and_20th_century_england_if_an_earl_died/
{ "a_id": [ "d1uzrd1" ], "score": [ 2 ], "text": [ "TL;DR -- that grandnephew could inherit the personal (non-real estate) property of the Earl if given to him in the Earl's will, but could not inherit the peerage title and (before the mid-late 20th Century) could not inherit real estate even if g...
[]
[]
[ [] ]
17zank
Drinking water while coughing
I was wondering why it helps to drink something when your coughing/choking? How does it help when liquid goes down your oesophagus and air goes down your trachea.
askscience
http://www.reddit.com/r/askscience/comments/17zank/drinking_water_while_coughing/
{ "a_id": [ "c8aa00g" ], "score": [ 2 ], "text": [ "When you're coughing, your body is attempting to clear the lungs of contaminants. This could be from an illness, or perhaps something in your throat. The bodies main idea is just to get up so you can swallow it or spit it out. By drinking water, ...
[]
[]
[ [] ]
1kurar
When was the first time a majority of humans understood the true shape and image of the planet, in your opinion?
Basically when did it become more han likely you could walk into any village in France or China and ask a person to locate where they are represented on that globe and you get a correct answer and not: "what the hell kind of weird looking sphere you got there in your hands friend?".
AskHistorians
http://www.reddit.com/r/AskHistorians/comments/1kurar/when_was_the_first_time_a_majority_of_humans/
{ "a_id": [ "cbtkslm" ], "score": [ 3 ], "text": [ "For the literate, scientific class, it varied depending on what part of the world they inhabited.\n\nAmong Greeks the idea dates to at least the 5th century BCE, but usually Aristotle is credited as the first to give sufficient proof of the spher...
[]
[]
[ [ "http://en.wikipedia.org/wiki/Globus_cruciger", "http://www.youtube.com/watch?v=7ne0GArfeMs", "http://en.wikipedia.org/wiki/Spherical_Earth" ] ]
3bqxvk
why doesn't netflix have some movies in hd, but only sd?
explainlikeimfive
http://www.reddit.com/r/explainlikeimfive/comments/3bqxvk/eli5_why_doesnt_netflix_have_some_movies_in_hd/
{ "a_id": [ "csomncu" ], "score": [ 5 ], "text": [ "If you are talking about that not all the movies have a HD version but do have a standard version, that would be because the movie wasn't produced in HD originally and no one have gone back to the original movie reel and converted it to an HD for...
[]
[]
[ [] ]
wqss0
How unrelated can two siblings be?
In terms of probability, lets say an absolutely perfect "roll" took place in which two siblings from the same parents received as little common DNA from their parents as possible, where sibling A received the father's input, Sibling B received the mother's and vice versa. What percentage of relation would they still b...
askscience
http://www.reddit.com/r/askscience/comments/wqss0/how_unrelated_can_two_siblings_be/
{ "a_id": [ "c5fnfnm", "c5fnqbd", "c5forfv" ], "score": [ 2, 3, 2 ], "text": [ "I'd like to add a bit to the question, as well. Theoretically I think, it'd be possible for me to share > 50% of my sister's genes (as well as < 50%). It is possible (and probably likely?) that I am...
[]
[]
[ [], [], [] ]
4tnb52
What did students memorize of Cicero's writings?
I just started reading Founding Brothers by Joseph J. Ellis. The first chapter describes the duel between Hamilton and Burr. One of Hamilton's insults to Burr was that Burr was like Catiline. The author briefly tells us that students of the time regularly memorized Cicero's Virtues and would have understood the referen...
AskHistorians
https://www.reddit.com/r/AskHistorians/comments/4tnb52/what_did_students_memorize_of_ciceros_writings/
{ "a_id": [ "d5jn6d5" ], "score": [ 3 ], "text": [ "I can't speak to *exactly* what they would have memorized, but can at least speak to education at the time as it pertains to Cicero's works.\n\nIn the 18th century, the classical education model was still in full effect. This meant that rhetoric...
[]
[ "http://surftofind.com/virtue" ]
[ [] ]
tk5l1
Is there any scientific data that supports the idea that stress causes one's hair to turn grey?
Long ago I seem to recall reading an article that completely blew this idea out of the water, that grey hair was purely a product of genetic predisposition, not tied in any way to external factors. Still, today, I hear lots of my well-educated friends treat the stress-causes-grey-hair idea like it's well-accepted. So, ...
askscience
http://www.reddit.com/r/askscience/comments/tk5l1/is_there_any_scientific_data_that_supports_the/
{ "a_id": [ "c4ndlu4", "c4ndq2d", "c4ne4r1", "c4ne80g" ], "score": [ 10, 22, 9, 10 ], "text": [ "[Here](_URL_0_) is a link to a previous AskScience discussion on the topic. I'm sorry that I can't provide more help, but I couldn't find any real sources through simple Googlin...
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[]
[ [ "http://www.reddit.com/r/askscience/comments/n1muz/can_stress_or_intense_fear_actually_cause_your/" ], [ "http://www.scientificamerican.com/article.cfm?id=fact-or-fiction-stress-causes-gray-hair" ], [], [] ]
3ctb6i
why cant you use a mirror to see something in the far distance without contacts/ glasses(provided you need them)?
explainlikeimfive
http://www.reddit.com/r/explainlikeimfive/comments/3ctb6i/eli5why_cant_you_use_a_mirror_to_see_something_in/
{ "a_id": [ "csyq73k", "csyqqm3" ], "score": [ 2, 2 ], "text": [ "Looking at an object 100 ft away through a mirror, and you're 3 feet from the mirror, it's going to be as if you're looking at it from 103 ft away. The mirror doesn't do anything to the light, just bounces it back at you...
[]
[]
[ [], [] ]
d41onc
Citation needed for basic facts? [x-post]
Hi all, I am a historian currently writing up a grant proposal. The history of the organisations I want to write about has hardly been covered in the literature before. The only study so far is an officially commissioned history that covers the basics. This, I mention in my literature review and say that this commiss...
AskHistorians
https://www.reddit.com/r/AskHistorians/comments/d41onc/citation_needed_for_basic_facts_xpost/
{ "a_id": [ "f06z5cl" ], "score": [ 2 ], "text": [ "Generally speaking, citations are only required for subjects that require proof and are otherwise not well known. During my time at University studying history, I was repeatedly lectured on wasting space on documents by citing information that wa...
[]
[ "https://www.reddit.com/r/AskAcademia/comments/d3y8x4/citation_needed_for_basic_facts/" ]
[ [] ]
30ssqx
Why, in popular media, are black holes depicted as flat? Wouldn't they be spherical like a planet?
askscience
http://www.reddit.com/r/askscience/comments/30ssqx/why_in_popular_media_are_black_holes_depicted_as/
{ "a_id": [ "cpvhetl", "cpvhz5n", "cpvl3ib", "cpvnrxv" ], "score": [ 61, 31, 2, 5 ], "text": [ "They are spherical, and they are generally depicted as such. It's just that when you portray a spherical object in a 2D image, it looks like a circle.\n\nWhat can be flat is the ...
[]
[]
[ [], [], [ "http://io9.com/the-truth-behind-interstellars-scientifically-accurate-1686120318" ], [ "http://www.cnet.com/news/scientists-create-worlds-darkest-material-super-black/" ] ]
3qkxtj
why does day light saving time work backwards? we get less daylight in the winter because of it?
Firstly, I did not grow up in a country that used DST, and this last week in the UK was my first experinece with it. However, for some weird reason I always assumed when Winter and early sunsets came, we'd push the clock down an hour to extend our days (hence the name day light savings time). But it seems it does the...
explainlikeimfive
https://www.reddit.com/r/explainlikeimfive/comments/3qkxtj/eli5_why_does_day_light_saving_time_work/
{ "a_id": [ "cwg20rz" ], "score": [ 3 ], "text": [ "It's basically double-dipping during the summer.\n\nWe love all of those daylight hours, so instead of sleeping through 1-2 hours of sun in the morning, we shift our clocks so we still all wake up as the sun rises and get to enjoy every hour of s...
[]
[]
[ [] ]
1ftbg6
Is a lightning strike more like a dam bursting or does it ramp up along the entire path ?
I'm not sure how to word the question correctly so I'll explain a little and maybe you can figure out what I'm asking. Lets say I run a pair of copper wires to the top of a 200ft tower to power a device at the top. Now a cloud to ground strike comes along. Does the huge surge of electrons start at the top of the wires...
askscience
http://www.reddit.com/r/askscience/comments/1ftbg6/is_a_lightning_strike_more_like_a_dam_bursting_or/
{ "a_id": [ "cadmtuw" ], "score": [ 4 ], "text": [ "In order for an [electrostatic discharge](_URL_1_) (such as a lightning) to happen, the [field strength](_URL_3_) must overcome the [dielectric strength](_URL_2_) of the dielectric medium (in our example - air). The dielectric then becomes a cond...
[]
[]
[ [ "https://en.wikipedia.org/wiki/Kirchhoff%27s_circuit_laws", "https://en.wikipedia.org/wiki/Electrostatic_discharge", "https://en.wikipedia.org/wiki/Dielectric_strength", "https://en.wikipedia.org/wiki/Electric_field" ] ]
3i19h7
Why was it customary to gaze away from the camera in early to mid-20th century portraits?
AskHistorians
http://www.reddit.com/r/AskHistorians/comments/3i19h7/why_was_it_customary_to_gaze_away_from_the_camera/
{ "a_id": [ "cuco125" ], "score": [ 20 ], "text": [ "It was most likely a stylistic choice and an attempt to capture a moment that looks more natural than someone staring into the camera saying \"cheese.\" In terms of how natural it is, candid photography, where the subject is unaware of the cam...
[]
[]
[ [] ]
25203h
are there any countries in the world that can realistically invade the us by force?
By air and sea like a full on invasion where we'd be seeing some serious shit. Or even like an event leading up to an invasion like the bombing of a coast or capture of a major port or something like that.. Just wondering if like Russia or China might have the capability to do this. Thanks! Edit: holy responses! It's...
explainlikeimfive
http://www.reddit.com/r/explainlikeimfive/comments/25203h/eli5_are_there_any_countries_in_the_world_that/
{ "a_id": [ "chcunw0", "chcuous", "chcupxc", "chcv093", "chcv1wr", "chcvcz9", "chcvdhl", "chcw5vr", "chcxhng", "chcxoyq", "chcyboj", "chcylju", "chcztms", "chd0xvm", "chd0yjt", "chd10mp", "chd27dd", "chd2aub", "chd2fwd", "chd2smu", "c...
[]
[]
[ [], [], [], [], [], [], [], [], [], [], [], [], [], [], [], [ "http://www.vice.com/read/we-asked-a-military-expert-if-the-whole-world-could-conquer-the-united-states" ], [], [], [], [], [ "http://www.netflix.com/WiMovie/70127225?trkid=2361637" ], [], [], [],...
ahloyw
can adam and eve produce all humans from genetic and scientific point of view ?
explainlikeimfive
https://www.reddit.com/r/explainlikeimfive/comments/ahloyw/eli5_can_adam_and_eve_produce_all_humans_from/
{ "a_id": [ "eefolgd", "eefqtkg", "eeftns9" ], "score": [ 6, 2, 2 ], "text": [ "I’m going to go with a nope on that one. Not in the time frame that we are talking, it’s meant to be a few thousand years? Even if we isolate one mutation and subsequent adaptations. \n\nEnvironmental c...
[]
[]
[ [ "https://en.m.wikipedia.org/wiki/Mitochondrial_Eve" ], [], [] ]
29mlqa
In the past, how did people use the Bible as an excuse for racism and segregation?
When the topic of gay marriage vs. the Bible comes up, many people mention that in the past, people tried to use the Bible as support for racism, segregation, or whatever other discriminatory things like that. Today, they say the Bible explicitly speaks against homosexuality. What evidence did people use to support t...
AskHistorians
http://www.reddit.com/r/AskHistorians/comments/29mlqa/in_the_past_how_did_people_use_the_bible_as_an/
{ "a_id": [ "cimyyin" ], "score": [ 2 ], "text": [ "Some Christian groups, especially in 19th century America, believed that the mark of Cain mentioned in the bible referred to black skin. The Southern Baptists and Mormons, for example, used the curse of Cain as justification for not allowing Blac...
[]
[]
[ [] ]
jeqnx
i'm five, explain how google works.
My five year old brain can't wrap itself around the complexity of this magic.
explainlikeimfive
http://www.reddit.com/r/explainlikeimfive/comments/jeqnx/im_five_explain_how_google_works/
{ "a_id": [ "c2bhnbx", "c2bhu06", "c2bjkle", "c2bjup0", "c2bhnbx", "c2bhu06", "c2bjkle", "c2bjup0" ], "score": [ 3, 5, 2, 2, 3, 5, 2, 2 ], "text": [ "[Already answered here](_URL_0_)\n\nEDIT: replaced short link with full url.", "I actual...
[]
[]
[ [ "http://www.reddit.com/r/explainlikeimfive/comments/j3ivm/explain_li5_how_a_computer_search_engine_works/" ], [], [ "http://www.radiolab.org/2007/aug/14/" ], [], [ "http://www.reddit.com/r/explainlikeimfive/comments/j3ivm/explain_li5_how_a_computer_search_engine_works/" ], [], [ ...
30lx4p
in this day and age, what does it mean to "capture" a city in syria?
I read [this BBC article](_URL_0_) about Syrian rebels "capturing" a city with a population of 100,000 people from government troops. How would they do that? What would it mean for the city's inhabitants? For the infrastructure in the town? Will water still run? Garbage collection? Who collects taxes?
explainlikeimfive
http://www.reddit.com/r/explainlikeimfive/comments/30lx4p/eli5_in_this_day_and_age_what_does_it_mean_to/
{ "a_id": [ "cptsgw0" ], "score": [ 3 ], "text": [ "Basically, what it happens is that militant group A enters a town and occupies it. By that I mean they take over the government control. (You have to imagine that a lot of these towns are more like free standing governments (township) that gets o...
[]
[ "http://www.bbc.com/news/world-middle-east-32100644" ]
[ [] ]
1fdx7q
the relationship between space and time
Is it a grid? I just have trouble understanding. So do larger things age slower? Or...yeah, if I was 5 years old, could you explain it?
explainlikeimfive
http://www.reddit.com/r/explainlikeimfive/comments/1fdx7q/eli5_the_relationship_between_space_and_time/
{ "a_id": [ "ca9c07e", "ca9c96y", "ca9cmlv", "ca9doct", "ca9g0b3", "ca9g5f6", "ca9iw75", "ca9kxph", "ca9mo6s", "ca9ok7b", "ca9qkhw", "ca9ytaz" ], "score": [ 4, 10, 42, 3, 7, 2, 4, 2, 2, 2, 2, 2 ], "text": [ "Sp...
[]
[]
[ [], [], [], [ "http://www.physicsforums.com/showthread.php?t=5732-1", "http://www.physicsforums.com/showthread.php?t=276815" ], [], [], [], [], [ "http://www.youtube.com/watch?v=rek7881OGRY" ], [], [], [] ]
vzo7m
Why does oxygen starvation cause euphoria?
askscience
http://www.reddit.com/r/askscience/comments/vzo7m/why_does_oxygen_starvation_cause_euphoria/
{ "a_id": [ "c596upi" ], "score": [ 2 ], "text": [ "I have studied drugs of abuse for many years, and all I can say is the following: People and other animals enjoy altered states of consciousness. Young children spin until they fall down, for fun. Humans and other animals enjoy a wide variety of ...
[]
[]
[ [] ]
lu4hr
Where can I find ancient original sources to read?
Hi, I'd like to read some original texts (translated of course, to english, spanish, german, french or russian). I'm interested in in everything round the age Iliad was written. But somehow I can't find even a list of the texts. Some help please :) **edit:** thanks everyone
AskHistorians
http://www.reddit.com/r/AskHistorians/comments/lu4hr/where_can_i_find_ancient_original_sources_to_read/
{ "a_id": [ "c2xmmib", "c2xmmib", "c2vmd33", "c2vncte", "c2voeqq", "c2vohgt", "c2vmd33", "c2vncte", "c2voeqq", "c2vohgt" ], "score": [ 2, 2, 12, 6, 5, 2, 12, 6, 5, 2 ], "text": [ "If you're interested in Roman period texts you...
[]
[]
[ [ "http://penelope.uchicago.edu/Thayer/E/Roman/home.html" ], [ "http://penelope.uchicago.edu/Thayer/E/Roman/home.html" ], [ "http://www.hup.harvard.edu/collection.php?cpk=1031" ], [], [ "http://www.hup.harvard.edu/collection.php?cpk=1031", "http://etcsl.orinst.ox.ac.uk/", "http...
16tn26
I have read stories of dogs "warning" their masters by whining of oncoming heart attack and other health concerns, can animals really sense health/mental issues, and how?
So I am super curious about this, I read about animals being super sensitive to those with mental and physical health issues, specifically dogs more often, but I am curious how this occurs. I'd also be curious if this is evident in other animals as well. Also if there is no definitive empirical evidence, what has rese...
askscience
http://www.reddit.com/r/askscience/comments/16tn26/i_have_read_stories_of_dogs_warning_their_masters/
{ "a_id": [ "c7z8k88", "c7za9um", "c7zlt3a" ], "score": [ 24, 5, 6 ], "text": [ "For starters, there have been numerous studies in which dogs have been trained to smell cancer, and then they have been able to detect breast and lung cancer just by sniffing a patient's breath, and wi...
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[]
[ [ "http://news.nationalgeographic.com/news/2006/01/0112_060112_dog_cancer.html" ], [ "http://gut.bmj.com/content/60/6/814.long", "http://ict.sagepub.com/content/5/1/30.long" ], [] ]
1wv8uh
Why would the third wave be the highest?
_URL_0_! In this video, a nuclear bomb is detonated underwater and it is mentioned that the third wave that hit the shore was the highest (and apparently the last). It would make intuitive sense for the first wave to be the highest because less energy is lost due to the lack of a recession. But the third wave would ha...
askscience
http://www.reddit.com/r/askscience/comments/1wv8uh/why_would_the_third_wave_be_the_highest/
{ "a_id": [ "cf5va7p" ], "score": [ 5 ], "text": [ "The first wave will be the acoustic shockwave of the explosion. this will be the sound wave of the nuke travelling through water and then becoming a wave as it reaches the beach and brings a small (relatively) mass of water with it. \nthe second ...
[]
[ "http://www.youtube.com/watch?v=Y53vDnNPiA4#" ]
[ [] ]
63v218
How did fighter pilots stave off boredom while flying in formation for hours towards the battleground?
According to wikipedia, The Zero had an enormous range, but how did pilots deal deal with the hours of empty ocean of travel time?
AskHistorians
https://www.reddit.com/r/AskHistorians/comments/63v218/how_did_fighter_pilots_stave_off_boredom_while/
{ "a_id": [ "dfxcb8v" ], "score": [ 4 ], "text": [ "Flying a WW2 era fighter was a pretty demanding job. Some larger airplanes did have simple autopilots back then but I don't know of any fighters that did. The engine's fuel mixture also had to be carefully monitored and adjusted to get the best p...
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[ [] ]
8fvruw
Are people with mental illnesses more likely to develop neurological diseases such as dementia and Alzheimers?
askscience
https://www.reddit.com/r/askscience/comments/8fvruw/are_people_with_mental_illnesses_more_likely_to/
{ "a_id": [ "dy7mhjn" ], "score": [ 5 ], "text": [ "Not necessarily. A mental illness (such as say Schizophenia) usually involves excessive function or loss of function in a particular region of the brain. In this case, it would be the dopamine system in what are called the mesocortical and mesoli...
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[ [] ]
br5vl2
when tectonic plates shift, why is there only an earthquake in a single place and not all along the plates' boundaries?
explainlikeimfive
https://www.reddit.com/r/explainlikeimfive/comments/br5vl2/eli5_when_tectonic_plates_shift_why_is_there_only/
{ "a_id": [ "eoadb46" ], "score": [ 9 ], "text": [ "As plates try to shift, the plate becomes locked as rocks on one side catch on rocks on the other side. The plate bends as the forces build up and the catch point gives, and you get an earthquake. This shifts load to other catch points, that migh...
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[ [] ]
81zq1z
how does a vasectomy work?
I dont quite understand the meaning of it I guess? After a vasectomy, how does a "shoot blank"? If the tubes are tied up, does excessive semen not make them burst from pressure? Where does the semen go, as it cant really get out of the tubes?
explainlikeimfive
https://www.reddit.com/r/explainlikeimfive/comments/81zq1z/eli5_how_does_a_vasectomy_work/
{ "a_id": [ "dv6d89r", "dv6entq", "dv6h5ll" ], "score": [ 11, 5, 10 ], "text": [ "They're not tied. They literally snip and cauterize the tubes that carry the sperm from the testicles. The semen part of it comes from a different place so you still ejaculate but there's no sperm in ...
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[]
[ [], [], [] ]
3wiwbq
why aren't the super fast gearshifts from a dual clutch gearbox bad for the engine?
explainlikeimfive
https://www.reddit.com/r/explainlikeimfive/comments/3wiwbq/eli5_why_arent_the_super_fast_gearshifts_from_a/
{ "a_id": [ "cxwjshj", "cxwnqdw" ], "score": [ 2, 2 ], "text": [ "Heavier engine means the parts are made from heavier and more resilient materials that can take a lot more stress.\n\nRace car engines have to be rebuilt after every race.", "_URL_0_\n\nIt seems that your answers will be...
[]
[]
[ [], [ "https://www.reddit.com/r/explainlikeimfive/search?q=dual+clutch&amp;sort=new&amp;restrict_sr=on&amp;t=all" ] ]
4t68aj
what is the squeaking sound i hear from my nose when it is stuffy?
My nose is a little stuffy right now and a few seconds after I blew it, I heard some "squeaking", coming from my nose as I felt the mucus moving. I've heard it before but never thought about it. What causes this?
explainlikeimfive
https://www.reddit.com/r/explainlikeimfive/comments/4t68aj/eli5_what_is_the_squeaking_sound_i_hear_from_my/
{ "a_id": [ "d5ewaxe" ], "score": [ 3 ], "text": [ "lol funny one :) \n\nIt's similar to when you whistle. Breathing normally doesn't make a sound, but you can move your tongue and mouth to create a resonance chamber that, when the air passes by it produces the whistle. \n\nNow your nose doesn't ...
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[ [] ]
42ppay
why do we translate words from arabic (like iraq and burqa) with a "q" when in english u is always supposed to follow q? if the language and script are completely different, why don't we just spell it phonetically (like irak)?
For that matter, why does English even require the "Q U" combination?
explainlikeimfive
https://www.reddit.com/r/explainlikeimfive/comments/42ppay/eli5_why_do_we_translate_words_from_arabic_like/
{ "a_id": [ "czc56rw", "czc57ep" ], "score": [ 5, 5 ], "text": [ "The q is based on transliterations of Arabic, which use the letter q to denote a sound not found in English.\n\nThe English qu combo comes from Latin, which also used qu the same way. As for why Latin did that, here's what W...
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[]
[ [], [] ]
725fcr
Why are American dollars often referred to as "bucks"?
AskHistorians
https://www.reddit.com/r/AskHistorians/comments/725fcr/why_are_american_dollars_often_referred_to_as/
{ "a_id": [ "dnfx9zn", "dng1fqk" ], "score": [ 118, 55 ], "text": [ "Post this at /r/etymology , you may get more answers", "This question is currently attracting a number of speculative, vague, or otherwise poor answers--all of which have been deleted. Please remember that this is Ask...
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[ [], [] ]
zfey9
why is pain satisfying when you're frustrated/angry?
explainlikeimfive
http://www.reddit.com/r/explainlikeimfive/comments/zfey9/why_is_pain_satisfying_when_youre_frustratedangry/
{ "a_id": [ "c644ymh", "c6463hl" ], "score": [ 2, 12 ], "text": [ "Can you elaborate? ", "The emotional parts of your brain are complex, but maybe not as complex as you think. Most of your emotions are regulated by the flow of a very few chemicals within your brain. These chemicals are...
[]
[]
[ [], [ "https://secure.wikimedia.org/wikipedia/en/wiki/Anger", "https://secure.wikimedia.org/wikipedia/en/wiki/Neurotransmitters" ] ]
22zdt7
How do scientists find "the gene" for something?
I know there are many genes, but how do they eventually find out what they're responsible for (if anything)? Why does it take so long? Is it also possible that more than 1 gene can be responsible for something?
askscience
http://www.reddit.com/r/askscience/comments/22zdt7/how_do_scientists_find_the_gene_for_something/
{ "a_id": [ "cgrz657", "cgs4q0h" ], "score": [ 6, 2 ], "text": [ "Well, it's tricky. If it is just \"Does gene A make Protein a1\", then it is pretty strait forward. Clone your gene into a host organism (e.coli or yest) and see what kind of protein comes out. Then we can start fiddling aro...
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[]
[ [], [ "http://www.reddit.com/r/askscience/comments/1y68o3/how_do_you_isolate_a_gene_from_one_organism_and/cfi4a3a" ] ]
322nw3
Why are humans so slow in comparison to other animals?
I know our peak speed is about 12 mph but that seems really slow in comparison to other animal. I mean, some snakes are faster than us. Is it because we learned to hunt and use tools over time and no longer depended on speed so it was selected out?
askscience
http://www.reddit.com/r/askscience/comments/322nw3/why_are_humans_so_slow_in_comparison_to_other/
{ "a_id": [ "cq7f26f", "cq7hvdq", "cq7n4xt" ], "score": [ 69, 89, 9 ], "text": [ "Humans aren't as fast in a sprint as some other animals, but we are among the best long-distance runners of all. It's an evolutionary trade off; no one body shape can be good at everything. Hunter-gat...
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[]
[ [], [ "http://en.wikipedia.org/wiki/Persistence_hunting" ], [] ]
5pwdmf
what is a "sigh," exactly, and why do we do it when we're sad or exasperated? does every culture sigh?
explainlikeimfive
https://www.reddit.com/r/explainlikeimfive/comments/5pwdmf/eli5_what_is_a_sigh_exactly_and_why_do_we_do_it/
{ "a_id": [ "dcufve7", "dcuk3j7", "dcuo6oa", "dcuy93v" ], "score": [ 6, 5, 9, 7 ], "text": [ "I might have to dig it up somewhere but there was a good response to this question before as it being a kind of \"emotional reset button\"", "What about sighs of exasperation? ...
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[]
[ [], [], [], [ "https://www.theguardian.com/science/2016/feb/08/a-sighs-not-just-a-sigh-its-a-fundamental-life-sustaining-reflex" ] ]
160pxc
Is there any electric potential difference between the planets? E.g., if Earth is ground, is Mars at 5 volts? If so, how is it measured?
askscience
http://www.reddit.com/r/askscience/comments/160pxc/is_there_any_electric_potential_difference/
{ "a_id": [ "c7rp1tl", "c7rqle3" ], "score": [ 6, 12 ], "text": [ "This is somewhat speculative, but in the ionosphere, free electrons would have a velocity more than sufficient to free them from the Earth's atmosphere, which might potentially be able to make the Earth's (if by Earth we're...
[]
[]
[ [], [ "http://cfs.nrcan.gc.ca/pages/160" ] ]
dxlq10
what does vanilla extract/essence taste like and what happens if i drink the stuff?
explainlikeimfive
https://www.reddit.com/r/explainlikeimfive/comments/dxlq10/eli5_what_does_vanilla_extractessence_taste_like/
{ "a_id": [ "f7s8ck6", "f7s8h9s" ], "score": [ 5, 3 ], "text": [ "Pure vanilla extract contains a surprisingly high percentage of alcohol. The FDA requires pure vanilla extract to contain no less than 35 percent alcohol, while most beer has an alcohol content of between two and nine percen...
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[ [], [] ]
aofbgq
why do competitions by radio or television companies ask questions that 99.999% know the answer to rather than just give the money away?
explainlikeimfive
https://www.reddit.com/r/explainlikeimfive/comments/aofbgq/eli5_why_do_competitions_by_radio_or_television/
{ "a_id": [ "eg0ev3k" ], "score": [ 14 ], "text": [ "In some legal jurisdictions, games of pure chance are illegal, but games of combined chance and skill aren't. By adding a trivial question, they can turn a random giveaway into a combined game of chance and skill, and thus avoid the prohibition...
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[ [] ]
qrwrb
Did our hunter gatherer ancestors get cancer?
You hear from primal diet proponents that most major diseases are due to our sedentary lifestyle and consumption of artificial food stuffs most recently, and grains a few thousand years back; does this hold up?
askscience
http://www.reddit.com/r/askscience/comments/qrwrb/did_our_hunter_gatherer_ancestors_get_cancer/
{ "a_id": [ "c3zy6r4", "c3zybbu", "c4008dc" ], "score": [ 4, 2, 2 ], "text": [ "Any multi-cellular organism is susceptible to cancer. With that, there are things in our lives now that may make us *more* susceptible (i.e. tobacco, high fructose corn syrup, CFCs). Also, our ancestors...
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[ [], [], [] ]
5hxnxr
why do we move our whole body around while playing a video game as if we are in the game?
Like if we were playing in VR type thing but we aren't playing VR we are just playing on our PC's it still happens.
explainlikeimfive
https://www.reddit.com/r/explainlikeimfive/comments/5hxnxr/eli5_why_do_we_move_our_whole_body_around_while/
{ "a_id": [ "db3rw9f" ], "score": [ 4 ], "text": [ "Your brain consists of neurons that are connected to one another, and these connections strengthen over time through repetition.\n\nIn your whole lifetime you've learned that the way to evade an object flying at your head is to move certain muscl...
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[ [] ]
9q10hp
if chip cards are more secure than swiping your card, why do some retailers who have chip reading terminals seem to have this feature disabled requiring you to swipe instead? i’ve even seen them go as far as to insert a piece of paper saying “no chip” into the reader.
explainlikeimfive
https://www.reddit.com/r/explainlikeimfive/comments/9q10hp/eli5_if_chip_cards_are_more_secure_than_swiping/
{ "a_id": [ "e85v13n" ], "score": [ 8 ], "text": [ "Enabling chip authentication requires updating their point of sale systems along with the back end software which interacts with it. All told adding chip capabilities to a single terminal can cost about $2000 each, and an organization would want ...
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[ [] ]
3g7n84
How large a dose of ionizing radiation would be necessary to kill someone in a short period of time?
I know that exposure to ionizing radiation is deadly in large doses, but death can take days or weeks. How large a dose would be necessary to bring on death in a matter of minutes or days? What would the physiological effects be of a dose this size?
askscience
http://www.reddit.com/r/askscience/comments/3g7n84/how_large_a_dose_of_ionizing_radiation_would_be/
{ "a_id": [ "ctvnnyr", "ctvp39c" ], "score": [ 6, 3 ], "text": [ "Radiation exposure gets to be usually lethal around 3 & ndash;8 Sv ([Sieverts](_URL_0_)), but at these levels death takes several weeks, and is due to \"hematopoietic syndrome\", where your body basically can't make blood an...
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[]
[ [ "https://en.wikipedia.org/wiki/Sievert" ], [ "http://www.cs.amedd.army.mil/borden/FileDownloadpublic.aspx?docid=2562a36d-571b-4af9-91c5-098947cb57f2", "https://www.reddit.com/r/askscience/comments/1k175x/can_exposure_to_an_incredibly_high_dose_of/", "https://books.google.com/books?id=QFemJs_jl...
3pvg27
What's the oldest recorded part of history that is so old that we literally can't obtain any information on anything older (ie. then up to religious interpretation)
AskHistorians
https://www.reddit.com/r/AskHistorians/comments/3pvg27/whats_the_oldest_recorded_part_of_history_that_is/
{ "a_id": [ "cw9vj0e", "cw9vsgp", "cw9yudq" ], "score": [ 31, 11, 2 ], "text": [ "I'm not sure about the idea that a part of history can be so old that we cannot get information about anything older. I'm not sure if you mean history or prehistory. Now depending on your definition o...
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[]
[ [ "http://imgur.com/iLVnsOy" ], [], [] ]
57dvs4
what are the advantages and disadvantages of using turboprops over turbojets?
Turboprops are essentially jet engines, but the rotational force is used to turn a propeller. Why do this?
explainlikeimfive
https://www.reddit.com/r/explainlikeimfive/comments/57dvs4/eli5_what_are_the_advantages_and_disadvantages_of/
{ "a_id": [ "d8r551y", "d8r5ea5", "d8r5ge4", "d8r5iw8" ], "score": [ 5, 2, 6, 2 ], "text": [ "It's _without controversy_ more fuel efficient on shorter flights. It's also true that on longer flights the jet wins. This has to do with the density of air at the _altitude_ at...
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[ [], [], [], [] ]
2vz8t0
why is there no charger for phones or laptops that automatically shuts down when full?
How hard can it be
explainlikeimfive
http://www.reddit.com/r/explainlikeimfive/comments/2vz8t0/eli5why_is_there_no_charger_for_phones_or_laptops/
{ "a_id": [ "com6652", "com6whu", "com7nf8" ], "score": [ 11, 53, 8 ], "text": [ "Newer phones/chargers do sort of do this. With my iPhone 6, once it reaches 100%, the battery will get down to ~97% before charging it back to 100%.", "The charging circuitry is almost always in t...
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[ [], [], [] ]
1hfjs0
What was the reasoning behind Robert E. Lee's Northern offensive?
Gettysburg ended up being a crushing blow for the South, but was it necessary for Lee to even be that far up North? Were the South unable to lead a war of attrition? The entire war was essentially about State's rights. So why even invade the Northern states when all they really wanted to do was secede? Did they intend ...
AskHistorians
http://www.reddit.com/r/AskHistorians/comments/1hfjs0/what_was_the_reasoning_behind_robert_e_lees/
{ "a_id": [ "catu7ft", "catvcbo", "caty82x" ], "score": [ 2, 5, 3 ], "text": [ "A lot of questions, I'll try to answer as many and as best as I can.\n\nThe first is a bit self-explanatory: one does not win a war by sitting on their ass at the homefront. Take it to the other guys' h...
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[ [], [], [] ]
2iarzo
What is at the second focus of an elliptical orbit?
Kepler's First Law says that the orbit of a planet is an ellipse with the Sun at one of the two foci. What is the other focus/what is at the other focus?
askscience
http://www.reddit.com/r/askscience/comments/2iarzo/what_is_at_the_second_focus_of_an_elliptical_orbit/
{ "a_id": [ "cl0ehnd" ], "score": [ 11 ], "text": [ "Nothing lives at the second focus. The uninhabited focus is just an unremarkable point in space." ] }
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[ [] ]
27a78r
How did fashion trends spread amongst the higher classes in Europe before the widespread availability of newspapers? Are there any examples of an important figure being out of date with significant consequences?
AskHistorians
https://www.reddit.com/r/AskHistorians/comments/27a78r/how_did_fashion_trends_spread_amongst_the_higher/
{ "a_id": [ "chyw00q" ], "score": [ 3 ], "text": [ "Newspapers themselves were not that important in fashion until probably the mid-to-late 1800s, at least in the U.S.\n\nInstead, fashion plates were all the rage. Fashion plates were drawings of women and sometimes men (but not usually together) w...
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[ [] ]
1mvm4m
Regarding the origins of Japanese people?
I'm sorry this is my first time asking this, because I had a tough time finding people of expertise to verify my claims. Japan is a fascinating country, and I have wanted to understand its history and origins for personal reasons. I have consulted some online resources, but none of them seems to be satisfactory. To p...
AskHistorians
http://www.reddit.com/r/AskHistorians/comments/1mvm4m/regarding_the_origins_of_japanese_people/
{ "a_id": [ "ccd1kqt" ], "score": [ 3 ], "text": [ "The video was painful to watch, but archeologists and anthropologists agree that the Yayoi people came to Japan from Korea cca 300BC and brought with them rice and the knowledge of metallurgy. The old Jomon culture were hunter-gatherers, possibly...
[]
[ "http://www.youtube.com/watch?v=xx6elRjoJBQ" ]
[ [] ]
kwj51
why is it so hard to find spammers?
It seems like all you have to do is buy some viagra or whatever, and work with the credit card company to see where the money goes. Why is it so hard to track down spammers? I assume the answer will be "because they're in lawless countries" but I find it hard to imagine that all spammers live in places where it's utte...
explainlikeimfive
http://www.reddit.com/r/explainlikeimfive/comments/kwj51/why_is_it_so_hard_to_find_spammers/
{ "a_id": [ "c2nsriu", "c2nss86", "c2nt16b", "c2nw5kd", "c2nx0p6", "c2nsriu", "c2nss86", "c2nt16b", "c2nw5kd", "c2nx0p6" ], "score": [ 4, 2, 2, 6, 3, 4, 2, 2, 6, 3 ], "text": [ "People who respond to the spam don't report it. ...
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[]
[ [], [], [ "http://gizmodo.com/5845448/this-is-how-microsoft-and-kapersky-labs-neutralized-a-spam-botnet", "http://www.theregister.co.uk/2011/03/17/rustock_botnet_takedown/" ], [], [ "http://en.wikipedia.org/wiki/BredoLab" ], [], [], [ "http://gizmodo.com/5845448/this-is-how-microso...
idrjx
Does my perception of time slow down when I run (ie have a high heart rate)?
So I've recently started running, and twice now have noticed something odd after I've been on my run for a while. A track will play on my iPod that's usually a track I play to pump myself up because it has a fast beat. Yet while I'm running (or even if I stop at the end of my run) it sounds like it's playing at half sp...
askscience
http://www.reddit.com/r/askscience/comments/idrjx/does_my_perception_of_time_slow_down_when_i_run/
{ "a_id": [ "c22xj1a" ], "score": [ 3 ], "text": [ "There's a field of study called [Time Perception](_URL_1_), though the Wikipedia page looks undercited. \n\n[Time distortion during traumatic events](_URL_0_) is well-documented anecdotally, but there's not a lot of formal research on it.\n\nPhys...
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[]
[ [ "http://www.sciencedirect.com/science/article/pii/S0005796706001227", "http://en.wikipedia.org/wiki/Time_perception", "http://en.wikipedia.org/wiki/Arousal" ] ]
6w2qwv
Do we need less energy to maintain our body temperature in a hot environment?
askscience
https://www.reddit.com/r/askscience/comments/6w2qwv/do_we_need_less_energy_to_maintain_our_body/
{ "a_id": [ "dm531qd" ], "score": [ 12 ], "text": [ "In general, *yes, the body requires less energy when warm than when cold to maintain a constant temperature.* Your body has a temperature that results from metabolism it needs to function. Fortunately, this generates a temperature pretty close t...
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[ [ "https://www.ncbi.nlm.nih.gov/pubmed/11113018" ] ]