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1qw3ek
how is a ghetto/ bad neighbourhood formed?
explainlikeimfive
http://www.reddit.com/r/explainlikeimfive/comments/1qw3ek/eli5_how_is_a_ghetto_bad_neighbourhood_formed/
{ "a_id": [ "cdh37ai", "cdh3xfb", "cdh7kt1" ], "score": [ 23, 33, 4 ], "text": [ "1. population density\n\n2. poverty- lack of jobs\n\n3. isolation caused by infrastructure (highways that create a physical barrier, large buildings, etc.)\n\n4. drugs\n\n5. lack of access to resource...
[]
[]
[ [], [], [] ]
181yop
What causes louder sounds to travel further than softer sounds?
I just wondered what the scientific explanation of it is.
askscience
http://www.reddit.com/r/askscience/comments/181yop/what_causes_louder_sounds_to_travel_further_than/
{ "a_id": [ "c8awyf1" ], "score": [ 2 ], "text": [ "Higher volume sounds directly correlate to the amount of energy they contain. There are two main factors for sound diminishing over distance. The first is the simple quadratic diminishing that happens as the sound has to spread out over an area. ...
[]
[]
[ [] ]
2w45m6
how do other countries program in languages such as php?
I countries such as Japan, I know English is a part of the curriculum, but how do they program in languages westerners use? Do the languages themselves get translated, or is it English-or-Bust? If we need to make sure something is on the server, we use `file_exists()`. Do they need to use that too? Or would they have...
explainlikeimfive
http://www.reddit.com/r/explainlikeimfive/comments/2w45m6/eli5_how_do_other_countries_program_in_languages/
{ "a_id": [ "conempi", "conenol", "conepee" ], "score": [ 6, 3, 5 ], "text": [ "It's English-or-Bust.\n\nIt's not all that weird though. A lot of industries operate in English; computer programming is one of them. Even though it might be easier for a native English speaker to lea...
[]
[]
[ [], [], [] ]
6viwuk
How can the constituents of carbon-12 add up to more than 12 u?
The unified atomic mass unit (u) is defined as a twelfth the mass of a carbon-12 atom. According to Wikipedia and other sources, a proton is about 1.007 u and a neutron about 1.009 u. That means carbon-12 should be about 12.10 u, even though by definition it is exactly 12 u. Using more significant figures or accounting...
askscience
https://www.reddit.com/r/askscience/comments/6viwuk/how_can_the_constituents_of_carbon12_add_up_to/
{ "a_id": [ "dm0lp2o", "dm0nets", "dm1vkzq" ], "score": [ 30, 3, 2 ], "text": [ "The mass of a bound system is not the same as the sum of the masses of its constituents. If it were, it would not be energetically favorable for the constituents to bind together in the first place.\n\...
[]
[]
[ [], [], [] ]
a1psmm
being knighted?
ELI5. Can women be knighted? What benefits are there to it? Somehow I only hear about celebrities being knighted?
explainlikeimfive
https://www.reddit.com/r/explainlikeimfive/comments/a1psmm/eli5_being_knighted/
{ "a_id": [ "earscua", "eartmuo", "earty0p" ], "score": [ 2, 5, 3 ], "text": [ "Yes. Well, no. Women become dames-are given imaginary titles. There is no SirThatcher, but there was a Baroness Thatcher.", "It differs a bit from country to country, but for example in Britain if a...
[]
[]
[ [], [], [ "https://www.gov.uk/government/uploads/system/uploads/attachment_data/file/714829/Birthday_Honours_2018_-_notes_on_the_higher_awards.pdf" ] ]
5lq78v
the main difference of a fruit and vegetable is that fruits have seeds. so, where the heck do vegetable seeds, used in gardeningand such, from?
[deleted]
explainlikeimfive
https://www.reddit.com/r/explainlikeimfive/comments/5lq78v/eli5_the_main_difference_of_a_fruit_and_vegetable/
{ "a_id": [ "dbxn7gb", "dbxn9l2" ], "score": [ 2, 3 ], "text": [ "Fruits are the seed-bearing structures of a plant while vegetables are the other parts of plants such as leaves (lettuce), roots (potatoes), and stems (celery). But this doesn't mean that vegetables don't *have* seeds, just ...
[]
[]
[ [], [ "http://www.mayoclinic.org/healthy-lifestyle/nutrition-and-healthy-eating/expert-blog/fruit-vegetable-difference/bgp-20056141" ] ]
a0w1sv
why plea insanity?
If you’re a mass murderer why would you ever plea insanity? Is there a benefit for being deemed insane instead of guilty?
explainlikeimfive
https://www.reddit.com/r/explainlikeimfive/comments/a0w1sv/eli5_why_plea_insanity/
{ "a_id": [ "eaksvov", "eaksxzc", "eal8l8b" ], "score": [ 5, 3, 7 ], "text": [ "The trick is proving temporary insanity, in which case you are not really responsible for the murder and are not likely to commit one again, leading to a lighter or possibly suspended sentence.", "T...
[]
[]
[ [], [], [] ]
52g72e
why wasn't there massive latino immigration to the us until the 1970's?
explainlikeimfive
https://www.reddit.com/r/explainlikeimfive/comments/52g72e/eli5why_wasnt_there_massive_latino_immigration_to/
{ "a_id": [ "d7jzz9f", "d7k09om" ], "score": [ 5, 9 ], "text": [ "Latin American immigration still existed it was just different. Look up info about the Bracero program if you want a little understanding on one of the things that started the major shift towards higher numbers of Latinos im...
[]
[]
[ [ "https://en.wikipedia.org/wiki/Bracero_program" ], [] ]
z302n
if we are living in a simulated universe, created particle by particle, are there any ways we could tell?
explainlikeimfive
http://www.reddit.com/r/explainlikeimfive/comments/z302n/eli5_if_we_are_living_in_a_simulated_universe/
{ "a_id": [ "c61088v", "c610guf" ], "score": [ 5, 3 ], "text": [ "Not unless we could see outside the universe and someone was there to tell us it was fabricated or left behind something for us to infer that from.\n\nBut would it matter?", "Depends on how good the simulation is.\n\nIf ...
[]
[]
[ [], [] ]
4p6u0z
Gas expands when heated. Gas cools when it expands. What gives?
It's been about a decade since I took AP chemistry...I can remember some things like "gas solubility in liquid increases as temperature of solvent decreases," but I can't remember *why*. It seems, intuitively, that if adding heat makes a gas expand, then an expanded gas should have more heat. What am I missing?
askscience
https://www.reddit.com/r/askscience/comments/4p6u0z/gas_expands_when_heated_gas_cools_when_it_expands/
{ "a_id": [ "d4iop2s", "d4jab63" ], "score": [ 7, 2 ], "text": [ "Both are true simultaneously. Suppose you heat up the gas in a balloon instantaneously. Since it is hotter (ie the gas molecules are moving faster) it will exert more pressure than before on the walls of the balloon and make...
[]
[]
[ [], [] ]
4k50dc
How do astronomers make observations about things like the speed of a galaxies rotation without watching it for centuries?
askscience
https://www.reddit.com/r/askscience/comments/4k50dc/how_do_astronomers_make_observations_about_things/
{ "a_id": [ "d3co8wm" ], "score": [ 16 ], "text": [ "I love 'How do we know' questions, so I'm happy to talk about this. For galactic rotation, the method we use is measurements of Doppler shift. Here's how it works:\n\nFirst, let me talk about hydrogen briefly. For reasons that come from quantum ...
[]
[]
[ [ "http://apod.nasa.gov/apod/ap110406.html", "http://www.atnf.csiro.au/outreach/images/astronomical/n3621.html", "http://apod.nasa.gov/apod/ap040409.html" ] ]
1p4dse
How do we see light from a structure 30 billion light-years away when the universe is 13.1 billion years old?
[In THIS article](_URL_0_) it is stated that "Because it takes light so long to travel from the outer edge of the Universe to us, the galaxy appears as it was 13.1 billion years ago", but being 30 billion light-years away it seems it should take light more than twice the age of the universe to get to us. I'm assuming t...
askscience
http://www.reddit.com/r/askscience/comments/1p4dse/how_do_we_see_light_from_a_structure_30_billion/
{ "a_id": [ "ccymd0b", "ccynps8" ], "score": [ 11, 5 ], "text": [ "The universe has always been expanding. The photons left 13 billion years ago when the galaxy was much closer, but the galaxy they came from has been getting further and further from us during the whole time that the photon...
[]
[ "http://www.bbc.co.uk/news/science-environment-24637890" ]
[ [], [] ]
491ytb
in space which way is up?
explainlikeimfive
https://www.reddit.com/r/explainlikeimfive/comments/491ytb/eli5_in_space_which_way_is_up/
{ "a_id": [ "d0oepe4", "d0oeq1w", "d0oeucc" ], "score": [ 4, 2, 3 ], "text": [ "Any way you choose.\n\nSome choices are made for you - for example if you're under thrust then your down will be towards the rockets - assuming they're at the back - and control panels often have writin...
[]
[]
[ [ "https://en.wikipedia.org/wiki/Docking_and_berthing_of_spacecraft#List_of_mechanisms.2Fsystems" ], [], [] ]
6p66q7
Would a swimmer be faster in salt water rather than fresh water?
This question piqued my interest due to shark week and Michael Phelps' race against the shark. Since all of his record settings times have been in fresh water, it would be fun to find out if this scenario being held in salt water would help or hurt his performance.
askscience
https://www.reddit.com/r/askscience/comments/6p66q7/would_a_swimmer_be_faster_in_salt_water_rather/
{ "a_id": [ "dknxd73" ], "score": [ 4 ], "text": [ "I would say the additional resistance and the additional thrust would cancel each other out.\rBut the higher buoyant force of sea water could be a downside as swimmers have to dunk their head underwater to lower the resistance.\r\rBut I'm not com...
[]
[]
[ [] ]
s48bu
Book on the history of time and historical perception of time?
Can anyone recommend a historical book on the subject of time and historical perception of time? I would like to read a general overview about time in world history, but I'm open for other suggestions too. It doesn't have to be an academic book, as long as it's somewhat accurate.
AskHistorians
http://www.reddit.com/r/AskHistorians/comments/s48bu/book_on_the_history_of_time_and_historical/
{ "a_id": [ "c4az3zd", "c4b0xzg" ], "score": [ 4, 3 ], "text": [ "_URL_0_\n\nThe Geography of Time by Robert Levine. Blew my mind the first time I read it.", "E.P. Thompson, \"Time, Work-discipline and Industrial Capitalism.\" Past & Present 38(1), 56-97 (1967).\n\nLooks at how the c...
[]
[]
[ [ "http://www.amazon.com/Geography-Of-Time-Tempo-Culture/dp/0465026427" ], [] ]
281yuo
Does being obese at some point in your life adversely affect how long you live? Even if you've since changed and become fit?
askscience
http://www.reddit.com/r/askscience/comments/281yuo/does_being_obese_at_some_point_in_your_life/
{ "a_id": [ "ci6q26m", "ci6q479", "ci7ib9l" ], "score": [ 17, 25, 2 ], "text": [ "_URL_0_\n\nTL;DR we don't really know one way or the other, more studies need to be done to establish the long term damage of obesity after the patient loses weight, though in the short term it is sho...
[]
[]
[ [ "http://hyper.ahajournals.org/content/45/6/1035.abstract" ], [ "http://bmjopen.bmj.com/content/2/4/e000828.short", "http://www.psychologytoday.com/blog/the-human-beast/201007/so-you-think-losing-weight-will-make-you-healthy-think-again", "http://singularityhub.com/2012/11/20/longevity-shocker-...
370oid
What are the requirements for something to have is own gravitational pull? ( does it need a solid center, how big, etc)
I'm curious as to how it works.
askscience
http://www.reddit.com/r/askscience/comments/370oid/what_are_the_requirements_for_something_to_have/
{ "a_id": [ "crirf7x", "criroge" ], "score": [ 10, 3 ], "text": [ "It needs to have some contribution to the [stress-energy tensor](_URL_0_). A little more simply, it needs to have mass (i.e. matter) or energy (i.e. light/radiation). So, basically everything has a gravitational pull, it mi...
[]
[]
[ [ "http://en.wikipedia.org/wiki/Stress%E2%80%93energy_tensor" ], [] ]
8bf7is
what is the difference between a normal person's brain and the brain of someone who has a personality disorder?
explainlikeimfive
https://www.reddit.com/r/explainlikeimfive/comments/8bf7is/eli5_what_is_the_difference_between_a_normal/
{ "a_id": [ "dx69nwn", "dx9s6hl" ], "score": [ 6, 2 ], "text": [ "Am layman who has spent lots of time in research of this, and also unfortunately has experience in this area. Other answers that get posted may do a better job of explaining or at least have specific sources to link. \n\nPer...
[]
[]
[ [], [] ]
cg36hr
why do children fight the urge to sleep?
explainlikeimfive
https://www.reddit.com/r/explainlikeimfive/comments/cg36hr/eli5_why_do_children_fight_the_urge_to_sleep/
{ "a_id": [ "eue9jri", "euec3kw", "euec8xb", "euev6nw" ], "score": [ 6, 6, 18, 2 ], "text": [ "I don't have a biological/psychological answer for this, but kids are energetic and would rather have fun even if they're being made to go to bed. It's a lot easier to sleep if yo...
[]
[]
[ [], [], [], [] ]
2ue1q5
If the length of the Earth's year was shorter in the past, why do we use the current Earth year length as a guide to describe the age of things in space, e.g. the Universe?
I hope this question is not too confusing as I have tried to simplify it as much as I could, not really very adept in science! The current models suggests that the Universe is about 13.7 billion years old, but surely that is based on the current length of year on Earth, which we all know is 365 days. I have seen on TV ...
askscience
http://www.reddit.com/r/askscience/comments/2ue1q5/if_the_length_of_the_earths_year_was_shorter_in/
{ "a_id": [ "co7kmbb", "co7mhmt", "co7mm9z", "co7n8zu", "co7nbvs", "co7o1nb", "co7o9gv", "co7p0na", "co7qnck", "co7sh61", "co7sqpf", "co7su1z", "co7tme6", "co7uor3", "co7vdr7", "co810q9", "co810ui", "co876qh" ], "score": [ 1334, 3, ...
[]
[]
[ [ "http://physics.nist.gov/cuu/Units/second.html" ], [], [], [], [], [], [], [], [], [], [], [], [], [], [], [], [], [] ]
159735
How is the force on light particles conceptualized?
If the characteristic equation for Force is **F = ma**, and photons have no mass, how is it that we can conceptualize a photon's interaction with other particles? Do we use the observed change in momentum of the massive particle and then deduce what kind of force was exerted by the photon retroactively? Or is there...
askscience
http://www.reddit.com/r/askscience/comments/159735/how_is_the_force_on_light_particles_conceptualized/
{ "a_id": [ "c7kd3ta" ], "score": [ 8 ], "text": [ "F = ma is a simplification/special case of a Newtonian principle that only applies to certain classical systems.\n\nFirst, Newton's second law is actually that F = dp/dt, which is to say that the force applied to an object is equal to the rate at...
[]
[]
[ [] ]
67w75t
How did people living in feudal Japan measure time?
I've read Shogun by James Clavell, and it's mentioned that people measured their date of birth by who was a reagent during that time. I'm curious how they referred to specific years, days, months, weeks, etc. Do the Japanese have a Zodiac system when referring to such things? I'm aware of the use of era, but I'm thi...
AskHistorians
https://www.reddit.com/r/AskHistorians/comments/67w75t/how_did_people_living_in_feudal_japan_measure_time/
{ "a_id": [ "dgu5v8v" ], "score": [ 3 ], "text": [ "Follow-up question: How aware would people living outside of Kyoto be of the current era name (*nengo*)? For example, I know in AD 708, the era was declared *Wado* (和銅) in honor of a copper discovery, but would most people even know the year chan...
[]
[]
[ [] ]
23pwx1
why is air invisible to infrared cameras? why isn't the entire image the temperature of the air? also, what is the relationship between infrared light and heat?
explainlikeimfive
http://www.reddit.com/r/explainlikeimfive/comments/23pwx1/eli5why_is_air_invisible_to_infrared_cameras_why/
{ "a_id": [ "cgzelyv" ], "score": [ 17 ], "text": [ "Infrared light is just like any other color of light, its just below the level that we can see. Heat is a measure of how much motion particles have. We know that hot things give off light- this is why metal glows when it gets hot, or why the sun...
[]
[]
[ [] ]
k9ud1
Can someone tell me why burning Mercury Thiocyanide causes it to grow 10x it's initial form?
[Here's](_URL_0_) the video I'm referring to for an example.
askscience
http://www.reddit.com/r/askscience/comments/k9ud1/can_someone_tell_me_why_burning_mercury/
{ "a_id": [ "c2ikrkl", "c2ikrkl" ], "score": [ 3, 3 ], "text": [ "Mercury thiocyanate undergoes decomposition at around 165 degrees so when it's set on fire, the substance produces Sulfur dioxide and mercuric vapor.\n\nThe decomposition of mercuric thiocyanate is an intumescent reaction, w...
[]
[ "http://www.youtube.com/watch?v=dX7xeF-ywxc&feature=related" ]
[ [], [] ]
5lkcvi
why goats climb on top of stuff, please.
explainlikeimfive
https://www.reddit.com/r/explainlikeimfive/comments/5lkcvi/eli5_why_goats_climb_on_top_of_stuff_please/
{ "a_id": [ "dbwcvq6", "dbwd0qt", "dbwdk0y" ], "score": [ 4, 2, 4 ], "text": [ "This just my guess but most animals try to climb on to stuff so they can see more. That way they can see predators that might come and attack them, and find prey (if they need to) or other food sources ...
[]
[]
[ [], [], [] ]
2w7men
How are we sure we are NOT the center of the universe?
I mean yes we see we are evolving around the sun and the sun around something else. On the largest scale though, we are the center of OUR observable universe, how can we know that the universe is larger than what we can observe and thus making us NOT the center?
askscience
http://www.reddit.com/r/askscience/comments/2w7men/how_are_we_sure_we_are_not_the_center_of_the/
{ "a_id": [ "cooc5c0", "coomp9u" ], "score": [ 17, 5 ], "text": [ "If we were the actual center, we'd start to see edge effects around the edge of the observable universe, but we don't. Any time that a medium is bounded by something else, there will be some sort of change at the interface....
[]
[]
[ [], [ "http://th.physik.uni-frankfurt.de/~scherer/Blogging/AdventsKalenderPlots/CMBPowerSpectrum.png", "http://en.wikipedia.org/wiki/Falsifiability" ] ]
1j9ybm
On earth aerodynamics dictate shape of vehicle. What shapes would be most optimal for spaceships?
askscience
http://www.reddit.com/r/askscience/comments/1j9ybm/on_earth_aerodynamics_dictate_shape_of_vehicle/
{ "a_id": [ "cbcl7xt", "cbco9uq", "cbcs0z5", "cbcxkxb", "cbd5e4y" ], "score": [ 9, 10, 6, 2, 2 ], "text": [ "Radiation shield cap towards the front. Assuming we are talking about far future then we would have to take into account going at speeds near c even a simple...
[]
[]
[ [], [ "https://en.wikipedia.org/wiki/Fullerene" ], [ "http://en.wikipedia.org/wiki/Gravity-gradient_stabilization", "http://en.wikipedia.org/wiki/Jupiter_Icy_Moons_Orbiter" ], [ "http://starshipengineer.blogspot.com/" ], [] ]
1k8bck
Multiply 2 negative numbers, you get a positive number. Multiply 2 imaginary numbers, you get a negative number. Can you have imaginary imaginary numbers which multiply to give imaginary numbers?
Can you have an infinite amount of imaginary number lines?
askscience
http://www.reddit.com/r/askscience/comments/1k8bck/multiply_2_negative_numbers_you_get_a_positive/
{ "a_id": [ "cbmghzy", "cbmgs05", "cbmq3hh" ], "score": [ 15, 2, 6 ], "text": [ " > Multiply 2 imaginary numbers, you get a negative number.\n\n5i * -4i = 20", "Quaternions are more or less this, you can see here: _URL_0_. You can extend this further and further, but each time...
[]
[]
[ [], [ "http://en.wikipedia.org/wiki/Quaternion", "http://en.wikipedia.org/wiki/Complex_number#Square_root" ], [ "http://en.wikipedia.org/wiki/Fundamental_theorem_of_algebra", "http://en.wikipedia.org/wiki/Field_(mathematics\\)", "http://en.wikipedia.org/wiki/Algebraic_closure", "http:/...
79lq8h
What is actually known about Roman gladiators? The revisionist view seems to be that they were professionals who barely ever killed each other while the traditional view is that they were mostly condemned slaves and criminals who were meant to die. Was it a mix of both?
AskHistorians
https://www.reddit.com/r/AskHistorians/comments/79lq8h/what_is_actually_known_about_roman_gladiators_the/
{ "a_id": [ "dp6zt3u", "dp3p3wl", "dp403hh", "dp49tsl", "dp5e0c1" ], "score": [ 20, 50, 98, 37, 3 ], "text": [ "Prepare for a wall of text. This is actually a very complex subject and one which I've tried to approach myself before and got swamped, so here is a gener...
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[ [], [ "https://www.reddit.com/r/RemindMeBot/comments/24duzp/remindmebot_info/", "https://www.reddit.com/message/compose/?to=RemindMeBot&subject=Reminder&message=%5BLINK%20INSIDE%20SQUARE%20BRACKETS%20else%20default%20to%20FAQs%5D%0A%0ANOTE:%20Don%27t%20forget%20to%20add%20the%20time%20options%20af...
sqwzm
Dark Matter: Could it be made up of cold neutrinos? Is there a process that would have create such enormous numbers of them to have the large-scale gravitational effect we see today? Are there any other non-exotic theories as to what dark matter may be?
Dark Matter: Could it be made up of cold neutrinos? Is there a process that would have create such enormous numbers of them to have the large-scale gravitational effect we see today? Are there any other non-exotic theories of dark matter's make-up? MOND is somewhat mundane, but that theory causes far more problems tha...
askscience
http://www.reddit.com/r/askscience/comments/sqwzm/dark_matter_could_it_be_made_up_of_cold_neutrinos/
{ "a_id": [ "c4g9aju" ], "score": [ 2 ], "text": [ "Technically, neutrinos *are* considered dark matter (they do not couple via the electromagnetic force). However, if my memory serves, you can do a back-of-the-envelope calculation which shows that the Standard Model neutrinos released during Big ...
[]
[]
[ [] ]
35k0vc
is it possible for a planet to exist in open space without orbiting anything?
Like would it eventually reach an orbit or what?
explainlikeimfive
http://www.reddit.com/r/explainlikeimfive/comments/35k0vc/eli5_is_it_possible_for_a_planet_to_exist_in_open/
{ "a_id": [ "cr54m4u", "cr55oqs" ], "score": [ 7, 2 ], "text": [ "yes, rogue or orphan planets orbit the galaxy alone. They are likely to be numerous, but they are near impossible to discover since they are not lit and their gravitational effects cannot be detected as a wobble in its star...
[]
[]
[ [], [ "http://www.amazon.com/Lockstep-A-Novel-Karl-Schroeder/dp/0765337266" ] ]
61vnmg
why do birds never shut up?
There's an enormous tree outside my window where the birds are making noise day and night. It never stops. Doesn't it take a lot of energy? Doesn't it reveal their location to predators?
explainlikeimfive
https://www.reddit.com/r/explainlikeimfive/comments/61vnmg/eli5_why_do_birds_never_shut_up/
{ "a_id": [ "dfhn8ne", "dfhn9ec", "dfi0mtn", "dfi9lfp" ], "score": [ 3, 35, 9, 3 ], "text": [ "You know the Reddit-ism, *doesn't matter, had sex*? That's a big part of it; bird songs are often a mating display.\n\nThey're also not all that costly: they don't take a lot of e...
[]
[]
[ [], [], [], [] ]
2mx1x1
Did any women partake in armed conflict in the American Revolutionary War? Perhaps as a militia member from a frontier area?
AskHistorians
http://www.reddit.com/r/AskHistorians/comments/2mx1x1/did_any_women_partake_in_armed_conflict_in_the/
{ "a_id": [ "cm9kb0c", "cm9maxo" ], "score": [ 2, 3 ], "text": [ "The best accredited woman who fought in the American Revolutionary War was Deborah Samson, who served in a Massachusetts Regiment for 3 years disguised as a man under the pseudonym of Robert Shirtliffe.\n\nShe was wounded tw...
[]
[]
[ [ "http://userpages.aug.com/captbarb/femvets.html" ], [] ]
4r2por
Where does electron's movements come from ?
I learned that the reason why magnetic atoms have their magnetic field is electron's movements, because movement of electrons produce electric field.. but where does this energy come from ? the movement of electrons around atoms.
askscience
https://www.reddit.com/r/askscience/comments/4r2por/where_does_electrons_movements_come_from/
{ "a_id": [ "d4xx59l", "d4yiclv", "d4yj08k" ], "score": [ 9, 3, 2 ], "text": [ "The magnetic field of electrons comes from their spin. In classical physics, we talk about the angular momentum of an object as something related to rate at which it rotates, like how the Earth spins. W...
[]
[]
[ [], [ "http://i.imgur.com/6YMZdWx.jpg", "http://i.imgur.com/8RJhMM3.png" ], [] ]
9gl6o3
what causes that echo/screech noise when driving across bridges?
I’ve noticed this mostly when I drive on the interstate, it’s hard to describe the noise. Sometimes it’s louder or softer, or at a higher or lower pitch. It’s more obvious with windows down. Is there something specifically that causes this?
explainlikeimfive
https://www.reddit.com/r/explainlikeimfive/comments/9gl6o3/eli5_what_causes_that_echoscreech_noise_when/
{ "a_id": [ "e64wxf0" ], "score": [ 2 ], "text": [ "It's the vibration of wheels due to a repeating pattern on the road. Usually these are grooves cut in to the road to improve drainage. The closer the interval, the higher the pitch.\n\nThere are [musical roads](_URL_0_) where artists have used ...
[]
[]
[ [ "https://en.m.wikipedia.org/wiki/Musical_road" ] ]
3xew4w
how are artificial waves created?
Oh, yeah sorry I didn't specify. I was talking about the waves on the water pools.
explainlikeimfive
https://www.reddit.com/r/explainlikeimfive/comments/3xew4w/eli5_how_are_artificial_waves_created/
{ "a_id": [ "cy41eup" ], "score": [ 3 ], "text": [ "\"Waves\" is an extremely broad term and \"artificial\" does little to narrow it. As a kid I produced artificial waves in a pool by bobbing up and down in an inner tube at just the right speed that the pool had rather tall waves. A flashlight a...
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[]
[ [] ]
7hod92
one belt one road initiative
explainlikeimfive
https://www.reddit.com/r/explainlikeimfive/comments/7hod92/eli5_one_belt_one_road_initiative/
{ "a_id": [ "dqskb4l" ], "score": [ 3 ], "text": [ "What do you want to know?\n\nIt is basically China's revived silk road. It is basically their overall strategy for trade and development with the rest of Eurasia and parts of Africa. \n\nThis encompasses several fronts: \n\n* Infrastructure - w...
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[]
[ [] ]
3e3tcz
how can cats/dogs smell a disease inside of a person?
explainlikeimfive
http://www.reddit.com/r/explainlikeimfive/comments/3e3tcz/eli5_how_can_catsdogs_smell_a_disease_inside_of_a/
{ "a_id": [ "ctb7mun" ], "score": [ 5 ], "text": [ "We don't really know. It's likely that certain disease cause your biochemistry to change and this might cause you to emit different levels of certain things the animals can smell. So they don't so much as smell the disease as they probably smell ...
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[]
[ [] ]
3tkiws
How do bacteria share resistance?
I saw a diagram in the news today - one bacterium became connected to another and a plasmid moved between them. It was cute 1. Is the transfer itself really this simple? Two bacterium bump into eachother, and boom - multidrug resistance. 2. What dictates the movement of DNA from one to another? How do they know the...
askscience
https://www.reddit.com/r/askscience/comments/3tkiws/how_do_bacteria_share_resistance/
{ "a_id": [ "cx713dv", "cxbfwdl" ], "score": [ 5, 2 ], "text": [ "There are multiple ways for bacteria to transfer DNA between each other (they are collectively called \"[horizontal transfer](_URL_0_)\") and the one you are talking about (called \"[conjugation](_URL_1_)\") is pretty simple...
[]
[]
[ [ "https://en.wikipedia.org/wiki/Horizontal_gene_transfer", "https://en.wikipedia.org/wiki/Bacterial_conjugation" ], [] ]
15mp9a
Why haven't we solved Chess yet? Are our current supercomputers capable of doing so?
askscience
http://www.reddit.com/r/askscience/comments/15mp9a/why_havent_we_solved_chess_yet_are_our_current/
{ "a_id": [ "c7nv93o", "c7o4p70" ], "score": [ 23, 5 ], "text": [ "The possibilities in a chess game increase exponentially by search depth. You can think of board states as like a tree: each branch is a different move that can be made, which branches down further per move. The [Shannon Nu...
[]
[]
[ [ "http://en.wikipedia.org/wiki/Endgame_tablebase", "http://en.wikipedia.org/wiki/Shannon_number", "http://en.wikipedia.org/wiki/Alpha-beta_pruning" ], [] ]
2a4u8y
Why don't Egyptian dynasties have names, like Chinese dynasties?
AskHistorians
http://www.reddit.com/r/AskHistorians/comments/2a4u8y/why_dont_egyptian_dynasties_have_names_like/
{ "a_id": [ "cirkfzw", "cirm7bs", "cirtm1b" ], "score": [ 357, 33, 22 ], "text": [ "One consideration with Egyptian dynasties is that there are just so many of them (37 by one count, spaning about 3000 years), it just makes more sense to group the dynasties together in larger perio...
[]
[]
[ [], [], [] ]
2l88pi
how can we have gpus that have a lot of cores with a decent clock rate, but our modern cpus have at best a handful of cores at a fast?
Why is it that I always hear about how some GPUs have thousands of cores at several hundred MHz, but when I look up CPUs, they have less than 20 cores, and around 4 GHz at best? EDIT: Title should say fast clock rate* at the end. EDIT 2: I should elaborate a little bit. I am asking how we can make GPUs with so many ...
explainlikeimfive
http://www.reddit.com/r/explainlikeimfive/comments/2l88pi/eli5_how_can_we_have_gpus_that_have_a_lot_of/
{ "a_id": [ "clsd6fo", "clsd7s7", "clsda6z" ], "score": [ 2, 2, 3 ], "text": [ "GPS cores are very simple and can only perform a small number of types of calculations. They are useful for doing a few things that need to be done massively in parallel, but they cannot function as a g...
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[]
[ [], [], [] ]
chalsq
how stock owners pay for stuff
explainlikeimfive
https://www.reddit.com/r/explainlikeimfive/comments/chalsq/eli5_how_stock_owners_pay_for_stuff/
{ "a_id": [ "euqylxk", "euqz3vz" ], "score": [ 3, 4 ], "text": [ "Either dividends, sale of stock, or borrowing against their stock holdings. \n\nIf the company pays dividends, even a small dividend becomes a large amount of money when one owns millions of shares. \n\nSelling stock reduc...
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[ [], [] ]
19mzzt
what is with all the gold-buying shops popping up all of the sudden?
In case location is relevant, I live in the Bay Area, California. I've been noticing all these gold buyers pop up out of nowhere. They're becoming as common as Starbucks over here, with a new one opening every week it seems. Is there any reason behind this? Is the gold economy booming? I have no idea...
explainlikeimfive
http://www.reddit.com/r/explainlikeimfive/comments/19mzzt/eli5_what_is_with_all_the_goldbuying_shops/
{ "a_id": [ "c8phmi5", "c8phwf7" ], "score": [ 5, 3 ], "text": [ "The price of gold isn't at the highest ever, but it's pretty close. And people are still in a bad state so selling that gold is more necessary then it was in other times.", "Gold buyers work on an arbitrage model: they ...
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[ [], [] ]
1bt1qo
Is the Chinese estimate of the Nanjing Massacre deaths exaggerated?
[This page](_URL_0_) on wikipedia makes some fairly convincing arguements, such as none of the international residents reported a massacre at the time, along with the population not shifting enough for 300,000 people to have been killed. How exaggerated, if at all, is the Chinese figure? What evidence is used to come u...
AskHistorians
http://www.reddit.com/r/AskHistorians/comments/1bt1qo/is_the_chinese_estimate_of_the_nanjing_massacre/
{ "a_id": [ "c99zyut" ], "score": [ 6 ], "text": [ "Did you even read your own link? It says at the top of the article that it's considered a revisionist stance even by *Japanese* historians, and the Nanjing Massacre article gives estimates by *Japanese* historians of around 200,000 deaths.\n\nRea...
[]
[ "http://en.wikipedia.org/wiki/Nanking_Massacre_controversy" ]
[ [] ]
1o6yyf
Have we ever witnessed a galaxy or star pass the event horizon of our visible universe?
I have heard that as bodies are farther away, their red shift shows that they are moving even faster, the further they are. That is, until a point at which they just vanish, instead of fade to darkness - never to be seen again.
askscience
http://www.reddit.com/r/askscience/comments/1o6yyf/have_we_ever_witnessed_a_galaxy_or_star_pass_the/
{ "a_id": [ "ccpq0qn" ], "score": [ 2 ], "text": [ "For this discussion in may be helpful to look at Fig. 3 (or middle of Fig. 1) from [this paper](_URL_3_). The paper is very good in general too for these questions.\n\nThe **observable universe** describes the furthest distance a particle could ...
[]
[]
[ [ "http://en.wikipedia.org/wiki/Hubble_sphere", "http://en.wikipedia.org/wiki/Cosmological_horizon#Event_horizon", "http://en.wikipedia.org/wiki/Particle_horizon", "http://www.mso.anu.edu.au/~charley/papers/DavisLineweaver04.pdf" ] ]
3e60jm
When did Macedonia become a primarily Slavic region, as opposed to a Hellenic region?
AskHistorians
http://www.reddit.com/r/AskHistorians/comments/3e60jm/when_did_macedonia_become_a_primarily_slavic/
{ "a_id": [ "ctbwvon", "ctc0awy", "ctc3eto" ], "score": [ 6, 24, 8 ], "text": [ "It hasn't. The region Macedonia, though largely in Greece, is spread out over several countries (see: _URL_1_ ). I still associate Macedonia with its hellenic past, despite the republic Macedonia claim...
[]
[]
[ [ "https://en.wikipedia.org/wiki/Macedonia_(Greece)", "https://en.wikipedia.org/wiki/Macedonia_(region)#/media/File:Greater_Macedonia.png" ], [ "https://en.wikipedia.org/wiki/Kuber", "https://upload.wikimedia.org/wikipedia/commons/c/c6/Ethnic_map_of_Balkans_-_german_1882.jpg", "https://en.wi...
1tdb5v
why is it that when people read orders from others such as "you're now breathing in manual mode", they become aware of breathing and find it laborious?
I just read several comments telling people that they're now aware of their breathing, or that they've now got an itch somewhere on their body that they just *have to* scratch, or manually blink, and others below are cursing the guy out for making them feel uncomfortable. Why do people become "aware" of these facts, w...
explainlikeimfive
http://www.reddit.com/r/explainlikeimfive/comments/1tdb5v/eli5_why_is_it_that_when_people_read_orders_from/
{ "a_id": [ "ce6si77", "ce6slqr", "ce6y4l4" ], "score": [ 14, 6, 2 ], "text": [ "All of the functions you describe are semi-autonomous. Normally, your body just kind of takes care of blinking and breathing by itself, like it does with your heart and digestive system. \n\nThe abilit...
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[]
[ [], [], [] ]
2l2jpd
why does it take hours to install big programs and games but seconds to uninstall it?
explainlikeimfive
http://www.reddit.com/r/explainlikeimfive/comments/2l2jpd/eli5_why_does_it_take_hours_to_install_big/
{ "a_id": [ "clqu2lx", "clqu4xj", "clqwrk3", "clqyaip", "clqyucn", "clqz2hz", "clr1955", "clr1jbe", "clr1lgi", "clr3lj2", "clr468p", "clr96t7", "clrbe9g", "clrggtp", "clrh7cz", "clrjwov" ], "score": [ 198, 26, 10, 2, 2, 2, ...
[]
[]
[ [], [], [], [], [], [], [], [], [], [], [], [], [], [], [], [] ]
7ksvlr
Which countries were among the first to ban the use of substances like alcohol or drugs for non-religious reasons?
AskHistorians
https://www.reddit.com/r/AskHistorians/comments/7ksvlr/which_countries_were_among_the_first_to_ban_the/
{ "a_id": [ "drgxj72" ], "score": [ 2 ], "text": [ "I'm sorry, but we don't allow 'First'/'Last' questions on /r/AskHistorians, and so we have removed this submission. It's not that the question is bad; it is simply that, given the rules of this subreddit, these types of questions are ill-suited t...
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[ [] ]
9p9hob
Books on U.S. involvement in Central America in the 80s
I've heard bits and pieces about how much of Central America was mired in civil war in the 80s, with the U.S. supporting certain right-wing groups during this time. For example, Óscar Romero's murder and recent elevation to sainthood, the murder of American nuns in El Savador, El Mozote and the attempts by Elliott Abr...
AskHistorians
https://www.reddit.com/r/AskHistorians/comments/9p9hob/books_on_us_involvement_in_central_america_in_the/
{ "a_id": [ "e8060hy", "e80g7yf" ], "score": [ 3, 2 ], "text": [ "\"Killing Hope: US and CIA Interventions Since World War II -- Updated through 2003\"\n\nBy William Blum. \n\n & #x200B;\n\nAs the title suggests, the book covers a wider time-frame and geographic region, but there are lots...
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[]
[ [], [] ]
5a3nf9
how are traditional film-based movies duplicated for mass distribution?
I know that film is film. It begins as a raw product, it's put in to a camera and becomes exposed, the film is developed, and then hits the cutting room, where the director selects scenes to cut and stich together into a movie. So now the movie is made. Presumably, there's a master cut. I've always wondered, how is t...
explainlikeimfive
https://www.reddit.com/r/explainlikeimfive/comments/5a3nf9/eli5_how_are_traditional_filmbased_movies/
{ "a_id": [ "d9dflod" ], "score": [ 4 ], "text": [ "Photography! \n\nThe original bit that the camera makes is a negative of the image it recorded. Passing light through that negative doesn't noticeably degrade the original in the slightest bit, and allows you to make a (nearly) perfect copy of t...
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[]
[ [] ]
tto6r
Realistically, how dangerous is using a mobile phone on a plane?
I was just on a flight, and the stewardesses were insistent that every phone, laptop and even mp3 player were turned off and put away before we began taxiing out for takeoff. I fly quite often, but this time the rules seemed to have been tightened up a lot compared to other occasions. With time to kill and nothing to ...
askscience
http://www.reddit.com/r/askscience/comments/tto6r/realistically_how_dangerous_is_using_a_mobile/
{ "a_id": [ "c4pmtf4", "c4pn55e", "c4pnnms", "c4pns60", "c4pofzt", "c4pp1vu", "c4pp9vc", "c4ppz4b", "c4pssq5" ], "score": [ 22, 8, 7, 5, 6, 2, 2, 5, 2 ], "text": [ "There's probably no danger at all from a properly manufactured and li...
[]
[]
[ [], [], [], [], [], [ "http://www.tuaw.com/2011/02/13/ipad-receives-faa-certification-as-an-electronic-flight-bag" ], [ "http://www.post-gazette.com/stories/opinion/perspectives/this-is-your-captain-turn-off-that-cell-phone-635634/" ], [], [ "http://asrs.arc.nasa.gov/search/database....
1mhxj6
why do we say "pharaoh" instead of "king of Egypt"?
AskHistorians
http://www.reddit.com/r/AskHistorians/comments/1mhxj6/why_do_we_say_pharaoh_instead_of_king_of_egypt/
{ "a_id": [ "cc9e4ho" ], "score": [ 5 ], "text": [ "Mostly because that is the descendant Egyptian term, and since it's easy to pronounce and very exotic sounding, Hollywood co-opted it early on. Since most of what your average American knows about Egypt comes from a single week/month in a single ...
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[]
[ [] ]
11n4xh
When two objects are moving away from each other near the speed of light, how does relativity determine which object "progresses" more through time?
We've all heard the classic scenario where if you left Earth on a spaceship traveling at near the speed of light, when you returned, time would have passed much greater than what you would have experienced. My problem comes from the fact that even though you are moving away from the Earth at near-light speed, isn't th...
askscience
http://www.reddit.com/r/askscience/comments/11n4xh/when_two_objects_are_moving_away_from_each_other/
{ "a_id": [ "c6nwil8", "c6nwj3f", "c6nxkfy" ], "score": [ 6, 3, 2 ], "text": [ "They would both observe time slowing down for the other one just as in the beginning of the twin paradox. If they then revered course and met up at the starting point, they then see the other one speedi...
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[ [], [], [] ]
1s8c4b
why are computer science and other computer related fields male-dominated?
Me and my roommates are talking about this and right now I understand why some fields are male-dominated because (like politics) because women were disadvantaged from the start by not being allowed to participate. However, I'm under the impression that the technological field developed relatively recently when women ha...
explainlikeimfive
http://www.reddit.com/r/explainlikeimfive/comments/1s8c4b/eli5_why_are_computer_science_and_other_computer/
{ "a_id": [ "cdux8dm", "cduxjey", "cduxlj8", "cduxu5l" ], "score": [ 3, 6, 9, 2 ], "text": [ "Computer science is male-dominated because it fits in with a lot of fields that are also male-dominated--things like electrical engineering, or engineering in general, as well as m...
[]
[ "http://www.nytimes.com/2008/11/16/business/16digi.html?_r=0" ]
[ [ "http://xkcd.com/385/" ], [], [], [] ]
2qeg14
When did people start celebrating Christmas?
AskHistorians
http://www.reddit.com/r/AskHistorians/comments/2qeg14/when_did_people_start_celebrating_christmas/
{ "a_id": [ "cn5j2oi" ], "score": [ 7 ], "text": [ "In the early Church, the Nativity of Christ was celebrated together with the feast of Theophany on Jan 6. At some point in the 4th century a separate Nativity feast was established, set at Dec 25. For several more centuries Theophany was still th...
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[]
[ [] ]
dxrhvk
does the moon peak the most at midnight just like how the sun does at noon?
explainlikeimfive
https://www.reddit.com/r/explainlikeimfive/comments/dxrhvk/eli5_does_the_moon_peak_the_most_at_midnight_just/
{ "a_id": [ "f7v47n8" ], "score": [ 3 ], "text": [ "moon is on a different orbit to the planet than the earth to the sun so it varies with the moon" ] }
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[ [] ]
uojk9
"The Wikipedia hypothesis"
A while ago someone told me that you can reach any article on Wikipedia from another one without ever having to press more than 10 links. Apparently called "The Wikipedia hypothesis". I was quite baffled by this and started testing. And so far I haven't found any two articles which this doesn't work for. But of course ...
askscience
http://www.reddit.com/r/askscience/comments/uojk9/the_wikipedia_hypothesis/
{ "a_id": [ "c4xdf2z", "c4xgs4q" ], "score": [ 2, 2 ], "text": [ "There is no way to mathematically prove this.\nIf i write an article with zero links in it, you can never reach it with links. Its really as simple as that.", "The standard way to deal with issues like this is called \"b...
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[]
[ [], [] ]
2edyu8
why does it seem as though dry cleaners are universally closed on sundays?
Hear me out, I realize that businesses need a break, but this a business that thrives mostly off of business people who work during the week. If a day off is so important why would it not be during the week like Monday or Tuesday?
explainlikeimfive
http://www.reddit.com/r/explainlikeimfive/comments/2edyu8/eli5why_does_it_seem_as_though_dry_cleaners_are/
{ "a_id": [ "cjykfkk" ], "score": [ 3 ], "text": [ "Because Sunday is a standard day for businesses to be closed or have reduced hours. " ] }
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[ [] ]
23rdxh
How do birds know when to come back after winter?
askscience
http://www.reddit.com/r/askscience/comments/23rdxh/how_do_birds_know_when_to_come_back_after_winter/
{ "a_id": [ "cgzvihg", "cgzvkga", "cgzxtur", "ch05s25", "ch07nnn" ], "score": [ 164, 36, 8, 2, 3 ], "text": [ "Birds know when to migrate by photoperiod, or the amount of daylight hours. As the photoperiod begins increasing after winter is over, birds are cued to mi...
[]
[]
[ [], [], [], [], [ "http://www.physicscentral.com/explore/action/pia-entanglement.cfm" ] ]
751o3a
If you placed wood in a very hot environment with no oxygen, would it be possible to melt wood?
askscience
https://www.reddit.com/r/askscience/comments/751o3a/if_you_placed_wood_in_a_very_hot_environment_with/
{ "a_id": [ "do2r9gu", "do2rwkg", "do2tbkc", "do2v01z", "do2w5dg", "do2w8v6", "do2wus4", "do2y6hy", "do322wj", "do34lls", "do37hw8", "do3alng", "do3i7d4", "do3mc8y", "do3pfgd", "do3qkud", "do3rbog", "do3x11f", "do41098", "do42o3h", "d...
[]
[]
[ [ "https://en.wikipedia.org/wiki/Pyrolysis", "https://link.springer.com/article/10.1007%2Fs10570-004-0344-3" ], [ "https://www.reddit.com/r/askscience/search?q=melt+wood&restrict_sr=on" ], [], [], [ "https://en.wikipedia.org/wiki/Pyrolysis", "https://en.wikipedia.org/wiki/Charcoa...
mv31o
How much science is in Morgan Freeman's show "Through the Wormhole" vs pseudoscience, speculation, and untestable postulations.
I generally like to consider myself a skeptic, and a scientifically minded person. Every time I watch this show, I feel that I am being fed a lot of unscientific information and unsubstantiated/untestable "what ifs". I don't want to single out any particular show within the series, but I was just curious if some peop...
askscience
http://www.reddit.com/r/askscience/comments/mv31o/how_much_science_is_in_morgan_freemans_show/
{ "a_id": [ "c343cs8", "c343cs8" ], "score": [ 7, 7 ], "text": [ "People who work in the fields being discussed tend not to watch these shows :) So it would be helpful if you could mention some particular claims this show is making which you're curious about.\n\nBut in general my impressio...
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[]
[ [], [] ]
a5ceiw
Did commanders give the order to "fire" arrows before gunpowder was common?
AskHistorians
https://www.reddit.com/r/AskHistorians/comments/a5ceiw/did_commanders_give_the_order_to_fire_arrows/
{ "a_id": [ "ebljnkk" ], "score": [ 2 ], "text": [ "Hi there! We've removed your question because it's asking about something like a name, a number, a date or time, a location, or the origin of a word - [basic facts](_URL_3_). We'd encourage you to instead post this question in the weekly, stickie...
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[]
[ [ "https://www.reddit.com/message/compose?to=%2Fr%2FAskHistorians", "https://www.reddit.com/r/AskHistorians/comments/505nw2/rules_roundtable_18_how_to_ask_better_questions/", "https://www.reddit.com/r/AskHistorians/search?sort=new&restrict_sr=on&q=flair%3ASASQ", "https://www.reddit.com/r/Ask...
jcadb
Is liquid soap "cleaner" than bar soap?
I like the not-slippery feeling on my hands after using a bar soap, but most people seem to think liquid soap is better than bar soap. What is the difference between the composition of bar soap and liquid soap, and does that difference make one more hygienic than the other? Edit: Can I add another question? Why does l...
askscience
http://www.reddit.com/r/askscience/comments/jcadb/is_liquid_soap_cleaner_than_bar_soap/
{ "a_id": [ "c2axpw2", "c2axt29", "c2ay7bk", "c2ayckr", "c2ayiog", "c2axpw2", "c2axt29", "c2ay7bk", "c2ayckr", "c2ayiog" ], "score": [ 5, 3, 2, 7, 13, 5, 3, 2, 7, 13 ], "text": [ "I would say that liquid would be more hygienic...
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[]
[ [], [], [], [], [], [], [], [], [], [] ]
35zeth
Has Shakespeare's work been consistently popular/celebrated since it was first performed? Or was it rediscovered at a certain point?
AskHistorians
http://www.reddit.com/r/AskHistorians/comments/35zeth/has_shakespeares_work_been_consistently/
{ "a_id": [ "cr99pg3", "cr9a2ae" ], "score": [ 75, 11 ], "text": [ "Shakespeare's plays were never completely lost, but performing live theatre was briefly banned in England in the Interregnum period about a generation after he died and his plays passed out of the public conscious for a fe...
[]
[]
[ [ "http://en.wikipedia.org/wiki/The_Globe_Theatre", "http://shakespearereinvented.files.wordpress.com/2012/12/coat-of-arms-on-shakespeare-centre.jpg", "http://www.folger.edu/", "http://en.wikipedia.org/wiki/Ben_Jonson", "http://internetshakespeare.uvic.ca/Library/facsimile/book/SLNSW_F1/3/?zoom=...
4xcfxm
How have Populists been viewed in America in the past?
This election cycle is the first time in my lifetime at least that we've had a mainstream candidate(s) in Sanders and Trump be called populists. However, when I hear them called this it's commonly meant as an insult, saying that they're running on a bunch of feel good speeches instead of honest, realistic policies. Has...
AskHistorians
https://www.reddit.com/r/AskHistorians/comments/4xcfxm/how_have_populists_been_viewed_in_america_in_the/
{ "a_id": [ "d6eeo7t" ], "score": [ 2 ], "text": [ "Please note that while this question was prompted by contemporary politics, the 20-year rule remains in effect. Please discussion -historical- populist movements in America rather than discussing whether Sanders or Trump are actually populists, e...
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[ [] ]
3scpg9
Do tracks at the beginning or end of an LP (vinyl) have higher/lower fidelity because of rotation speed?
askscience
https://www.reddit.com/r/askscience/comments/3scpg9/do_tracks_at_the_beginning_or_end_of_an_lp_vinyl/
{ "a_id": [ "cwwql4k" ], "score": [ 2 ], "text": [ "I would like to piggyback on OP's question here and ask if it is true that traditional pivoting tonearms do not track at the same angle throughout the length of a record as opposed to linear tracking tonearms which supposedly do. Also if this is ...
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[ [] ]
3sag5c
why are coding languages so hard to understand?
I don't mean this as in they have a learning curve, I mean in the sense of their intuitiveness. For example Javascript's regex's: function toTitleCase(str) { return str.replace(/\w\S*/g, function(txt){return txt.charAt(0).toUpperCase() + txt.substr(1).toLowerCase();}); }
explainlikeimfive
https://www.reddit.com/r/explainlikeimfive/comments/3sag5c/eli5_why_are_coding_languages_so_hard_to/
{ "a_id": [ "cwvg58a", "cwvg60g", "cwvgdoc", "cwvge3w", "cwvgszg", "cwvgzrk", "cwvil87" ], "score": [ 15, 30, 27, 8, 5, 2, 2 ], "text": [ "The languages were made to be easy to understand without limiting functionality. Many of the functions in your ...
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[ [], [], [], [], [], [], [] ]
ik7i9
Why is the ISS in such low orbit?
The ISS is on such a low orbit that it scrapes the atmosphere and has to spend constant fuel to align it's orbits, so when/if we retire it it will fall back down to earth. If it was significantly higher, could we keep the ISS in constant orbit so that if we lack the funds to keep it up we could temporarily shut it down...
askscience
http://www.reddit.com/r/askscience/comments/ik7i9/why_is_the_iss_in_such_low_orbit/
{ "a_id": [ "c24f0lx" ], "score": [ 3 ], "text": [ "It would take a lot more energy to get there, which would reduce the payload capacity of a vehicle going to it (since you would need to bring more fuel). This would mean the modules would have to be smaller as well.\n\nNow that the space shuttle ...
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[ [] ]
71y74i
why is there so much activity with the ring of fire recently? how do we know which earthquakes are directly linked? should california be as worried as the media makes out?
explainlikeimfive
https://www.reddit.com/r/explainlikeimfive/comments/71y74i/eli5_why_is_there_so_much_activity_with_the_ring/
{ "a_id": [ "dnee2sk", "dnefvdb", "dnei3rr", "dneo4bg" ], "score": [ 26, 63, 13, 18 ], "text": [ "The surface of the earth is collection of huge 'plates' that float over a layer of partly solid and partly molten rock called magma; collectively referred to as the earth's '...
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[ [], [], [], [] ]
183uhi
why do perishable ingredients such as butter, milk, or eggs no longer have to be refrigerated after they've been baked into a cake or cookies?
explainlikeimfive
http://www.reddit.com/r/explainlikeimfive/comments/183uhi/why_do_perishable_ingredients_such_as_butter_milk/
{ "a_id": [ "c8bd5mk", "c8bh004", "c8bn46d", "c8bn9mz" ], "score": [ 24, 69, 4, 3 ], "text": [ "Butter, milk and eggs don't have to be refrigerated. It's *customary*, particularly in the United States, to keep them in the refrigerator, but it isn't necessary.\n\nInteresting...
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[ [], [ "http://en.wikipedia.org/wiki/French_butter_dish" ], [], [] ]
33kk7l
What did the Romans do to celebrate 1000 years (a millennium) of Rome?
Assuming they observed its birthday or otherwise counted Its years.
AskHistorians
http://www.reddit.com/r/AskHistorians/comments/33kk7l/what_did_the_romans_do_to_celebrate_1000_years_a/
{ "a_id": [ "cqlvo14", "cqmd4nx" ], "score": [ 522, 20 ], "text": [ "The founding date of the city of Rome (ab urbe condita) was not always agreed upon, but by the time of Philip the Arab, it was commonly held to be April 21, 753 BC. \n\nIn 248 AD, there were massive festivities, including...
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[ [ "https://www.wikiwand.com/en/Philip_the_Arab#/Ludi_Saeculares", "https://en.wikipedia.org/wiki/Secular_Games", "https://en.wikipedia.org/wiki/Saeculum" ], [] ]
1ue3co
What sort of government where the conspirators of the 20 July Plot to kill Hitler planning on implementing, and what were their plans for gaining peace with Nazi Germany's enemies and the territory they'd gained?
AskHistorians
http://www.reddit.com/r/AskHistorians/comments/1ue3co/what_sort_of_government_where_the_conspirators_of/
{ "a_id": [ "ceh93za", "cehdwod", "cehg1oy", "cehha3p" ], "score": [ 168, 12, 9, 3 ], "text": [ "[The first paragraph on the 20 July Plot's Wikipedia article says that no details of the peace plans have emerged](_URL_2_), and it cites three independent sources, so I doubt w...
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[]
[ [ "http://en.wikipedia.org/wiki/German_resistance#Relations_with_Allies", "http://en.wikipedia.org/wiki/Operation_Valkyrie#Initial_order_to_the_Wehrkreise", "http://en.wikipedia.org/wiki/20_July_plot#Background", "http://en.wikipedia.org/wiki/20_July_plot", "http://en.wikipedia.org/wiki/Henning_...
6bo7kd
William F. Buckley did not support the Civil Rights movement because he did not believe protests were appropriate for the cause. Was this a typical conservative view in the 1950s and 1960s?
AskHistorians
https://www.reddit.com/r/AskHistorians/comments/6bo7kd/william_f_buckley_did_not_support_the_civil/
{ "a_id": [ "dhozeew" ], "score": [ 27 ], "text": [ "May I question the assumption behind the question? William F. Buckley didn't support the Civil Rights movement because he was a racist. He outright stated that the white race was superior.^^1 His defence of that statement was around the idea tha...
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[]
[ [ "http://www.nytimes.com/2004/07/11/magazine/way-we-live-now-7-11-04-questions-for-william-f-buckley-conservatively-speaking.html>&gt" ] ]
5rn3tj
what happens if you only eat rarely/one small meal a day?
I know starvation/dehydration have their horrible side effects, but what would happen if a person just goes extremely long periods without eating?
explainlikeimfive
https://www.reddit.com/r/explainlikeimfive/comments/5rn3tj/eli5_what_happens_if_you_only_eat_rarelyone_small/
{ "a_id": [ "dd8k4kf" ], "score": [ 5 ], "text": [ "An important thing to remember about fasting and starvation is that the only fuel that the brain can use is glucose. Other tissues can use protein, fat or glucose to get energy - but the brain can only use glucose. \n\nBut glucose gets used prett...
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[ [] ]
3mn59p
why are total lunar eclipses so rare?
I'm having a hard time visualizing exactly why it is that lunar eclipses are so rare. Shouldn't the earth's shadow project onto the moon relatively often? What is it that I am missing?
explainlikeimfive
https://www.reddit.com/r/explainlikeimfive/comments/3mn59p/eli5_why_are_total_lunar_eclipses_so_rare/
{ "a_id": [ "cvgenxq", "cvgeo82" ], "score": [ 4, 5 ], "text": [ "The Moon's orbit goes \"above\" and \"below\" the Earth's (if you think of Earth as orbiting in a flat plane). It has to be both _behind_ the Earth, and aligned with its plane, for an eclipse to occur, and that usually doesn...
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[ [], [ "http://www.uni.edu/morgans/astro/course/Notes/section1/nodes.gif" ] ]
avnw4z
If a photon has momentum, wouldn't it appear to be going faster than the speed of light relative to the particle that emitted it?
Would the particle be pushed back by the conservation of momentum? Wouldn't the particle be moving away from the photon, relative to the photon, at a speed slightly greater than c? Google had no quick answer, sorry that I'm not great at physics
askscience
https://www.reddit.com/r/askscience/comments/avnw4z/if_a_photon_has_momentum_wouldnt_it_appear_to_be/
{ "a_id": [ "ehgme87", "ehgs2v9" ], "score": [ 41, 8 ], "text": [ "You're right that to conserve momentum the particle would need to recoil because the photon it created carries linear momentum. Under pre-1905 physics the particle would see the photon velocity as c+v where v is the recoil ...
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[ [], [] ]
120ttf
How long till we can grow back limbs?
Like an arm, or an leg?
askscience
http://www.reddit.com/r/askscience/comments/120ttf/how_long_till_we_can_grow_back_limbs/
{ "a_id": [ "c6r8ltb", "c6rb9n0", "c6rekti" ], "score": [ 5, 5, 2 ], "text": [ "This is already somewhat possible through methods similar to this article (_URL_0_).", "This is a brutally open-ended question. Are you suggesting we will evolve to have this like other species? Or ...
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[ [ "http://health.howstuffworks.com/human-body/cells-tissues/extracellular-matrix.htm" ], [ "http://www.ncbi.nlm.nih.gov/pubmed/18552863", "http://articles.nydailynews.com/2012-09-30/news/34181322_1_new-ear-sherrie-walter-basal-cell", "http://en.wikipedia.org/wiki/Gene_therapy_for_color_blindness...
97ix7e
Did Jewish slaveowners in the South teach their slaves Judiasm?
So we know that many slave owners used Christianity to try to make their slaves submissive. We also know that there were Jewish slaveowners in the America South. Did Jewish slaveowners “raise” their slaves in the Jewish tradition.
AskHistorians
https://www.reddit.com/r/AskHistorians/comments/97ix7e/did_jewish_slaveowners_in_the_south_teach_their/
{ "a_id": [ "e48zdbr", "e5ctcyx" ], "score": [ 31, 2 ], "text": [ "There is an older answer on [this thread: ](_URL_1_) and a [comment](_URL_0_) by /u/gingerkid1234 specifically the part where they mention *\"What's important to remember here is that prior to the mass immigration of Jews t...
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[ [ "https://www.reddit.com/r/AskHistorians/comments/2r5x0g/were_there_jewish_slave_owners_in_america/cndih2f/", "https://www.reddit.com/r/AskHistorians/comments/2r5x0g/were_there_jewish_slave_owners_in_america/", "https://www.theatlantic.com/magazine/archive/1995/09/slavery-and-the-jews/376462/" ], [...
6fuuvq
why are white rats mainly used for studies instead of other rodent species?
explainlikeimfive
https://www.reddit.com/r/explainlikeimfive/comments/6fuuvq/eli5_why_are_white_rats_mainly_used_for_studies/
{ "a_id": [ "dil4o01", "dil4ufq" ], "score": [ 2, 6 ], "text": [ "They are a standadized lab rat, bred for this purpose, readily available in large numbers. But actually, mice are used more.\n\n_URL_0_", "Lab rats are often of a particular strain, or a family that mice are taken from t...
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[ [ "https://en.wikipedia.org/wiki/Laboratory_rat" ], [] ]
61y73f
why are the edges of transparent objects (glass, plastic, acrylic) almost opaque?
Examples: [Image](_URL_0_), [Image](_URL_1_)
explainlikeimfive
https://www.reddit.com/r/explainlikeimfive/comments/61y73f/eli5_why_are_the_edges_of_transparent_objects/
{ "a_id": [ "dfi82vk" ], "score": [ 6 ], "text": [ "Because light entering the edges is entering at a sharp angle, is bent to travel through the length of the material, bouncing off the sides until it exits the other end. Similarly, the light you see coming out of the edges has already travelled t...
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[ "http://vignette1.wikia.nocookie.net/powerlisting/images/1/15/Glass.png/revision/latest?cb=20170107211823", "https://images-na.ssl-images-amazon.com/images/I/51dGY%2BgwP1L.jpg" ]
[ [] ]
19chvt
why do we curse as a reflex?
Well, when something gets messed up we often react by cursing. It's almost a reflex. I say almost because I never curse in front of my father and am otherwise doing it around friends.
explainlikeimfive
http://www.reddit.com/r/explainlikeimfive/comments/19chvt/eli5_why_do_we_curse_as_a_reflex/
{ "a_id": [ "c8mtp01", "c8muslj", "c8mvwer", "c8mvwl0" ], "score": [ 2, 7, 18, 8 ], "text": [ "I would think it is just a learned behavior. As children we see swearing from our parents, the media, and our peers and some of us develop the desire to swear because it's new and...
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[ [], [], [], [] ]
26qcyb
what would be the protocol for abandoning the current us constitution?
Is this even possible?
explainlikeimfive
http://www.reddit.com/r/explainlikeimfive/comments/26qcyb/eli5_what_would_be_the_protocol_for_abandoning/
{ "a_id": [ "chtgv2e", "chtgv7a", "chtgwp4" ], "score": [ 2, 3, 5 ], "text": [ "We couldn't remove the constitution, but with a 2/3 vote in congress and then 3/4 of the state's ratifying we could delete and replace everything within it.", "Theoretically, you could pass an amend...
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[ [], [], [] ]
8bdi90
what exactly is a light year?
explainlikeimfive
https://www.reddit.com/r/explainlikeimfive/comments/8bdi90/eli5_what_exactly_is_a_light_year/
{ "a_id": [ "dx5v3v0" ], "score": [ 2 ], "text": [ "A light year is the distance light can travel in one year. It is equivalent to 5.879e+12 miles or 9.461e+12 kilometers. " ] }
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[ [] ]
a7gywz
Why aren't our satellites that orbit within the Roche limit torn apart?
askscience
https://www.reddit.com/r/askscience/comments/a7gywz/why_arent_our_satellites_that_orbit_within_the/
{ "a_id": [ "ec3fr4m", "ec3g4py" ], "score": [ 24, 12 ], "text": [ "The roche limit is calculated assuming that the object is only held together by gravity. For very large objects, other forces are small in comparison to gravitational forces. For small, sturdy objects, like manmade satelli...
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[ [], [] ]
13yx8v
A question on optical metamaterials.
If one was to construct a cube of material that had a 600 000 km network of light channeling conduit throug it, would one be able to enter light in one side and have it come out the otherside 2 seconds afterwards? Also if possible are there any plausible applications for this?
askscience
http://www.reddit.com/r/askscience/comments/13yx8v/a_question_on_optical_metamaterials/
{ "a_id": [ "c78ec74" ], "score": [ 2 ], "text": [ "So you're picturing like a window with a bunch of fiber optic cables which were tangled around before leaving the other side of the window?" ] }
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[ [] ]
3vka1a
why can't tv channels just upload their shows to youtube?
I mean, it's a win for everybody! Viewers can watch it whereever they are on the globe for free, and the companies will get more people watching their show.
explainlikeimfive
https://www.reddit.com/r/explainlikeimfive/comments/3vka1a/eli5_why_cant_tv_channels_just_upload_their_shows/
{ "a_id": [ "cxo7ybz", "cxo843v", "cxo86h1" ], "score": [ 3, 3, 2 ], "text": [ "TV companies don't make money from you watching their show. They make money selling advertisements, which you would be less likely to do on YouTube. Unless they use product placement, which if cord cutt...
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[ [], [], [] ]
ew10km
rain water has no salt, but eventually gets back to an ocean from streams and rivers. surface water on the ocean condensates into clouds to repeat the cycle, but where does the salt go?
explainlikeimfive
https://www.reddit.com/r/explainlikeimfive/comments/ew10km/eli5_rain_water_has_no_salt_but_eventually_gets/
{ "a_id": [ "ffz6ill", "ffz6imf" ], "score": [ 3, 4 ], "text": [ "if you try to boil salt water you'll se once the water has completely evaporated the salt is left on the bottom", "The salt stays in the ocean; it doesn't evaporate with the water. Only the water evaporates into vapor." ...
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[ [], [] ]
f3p4n7
Our common ancestor.
When we look back history often tells it's story through the eyes of great men. Are there any historical tellings through the eyes of the common person? I recently learned my great-grandfather didn't get drafted to WW2 because, he was the head of the household and had to stay back, to look after the farm and family. T...
AskHistorians
https://www.reddit.com/r/AskHistorians/comments/f3p4n7/our_common_ancestor/
{ "a_id": [ "fhkaaav" ], "score": [ 9 ], "text": [ "Yes and no. Many developments in history writing (especially since the 1960s) have been concerned with understanding history 'from below' - that is, what was life like for people who weren't at the top of society. A famous text that helped kickst...
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3h4q40
how do people learn to float?
When learning to swim, the first thing you must learn is how to float. Based on my understanding of basic physics, buoyancy force is equal to the mass of fluid displaced by an object. Assuming this is correct, how is floating an acquired skill?
explainlikeimfive
http://www.reddit.com/r/explainlikeimfive/comments/3h4q40/eli5_how_do_people_learn_to_float/
{ "a_id": [ "cu46zkk", "cu47527" ], "score": [ 2, 2 ], "text": [ "Not an answer to the question, but I wanted to ask where you have to learn how to float first before learning how to swim? Yes you have to be able to keep your head over the water using thrust created by your feet, but never...
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[ [], [] ]
put0m
stock market from a corporation and stock buyer view.
explainlikeimfive
http://www.reddit.com/r/explainlikeimfive/comments/put0m/eli5_stock_market_from_a_corporation_and_stock/
{ "a_id": [ "c3sgc5y" ], "score": [ 4 ], "text": [ "Suppose that you want to start a company, but don't have enough money. So you ask a friend for money and in return you give him some ownership in the company. This is private ownership since only you and your friend have control of it.\n\nCorpora...
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n2sfx
how is gravity a theory.
I hear it many times but never understood what it means.
explainlikeimfive
http://www.reddit.com/r/explainlikeimfive/comments/n2sfx/eli5_how_is_gravity_a_theory/
{ "a_id": [ "c35tcug", "c35w8do", "c35tcug", "c35w8do" ], "score": [ 7, 2, 7, 2 ], "text": [ "Wikipedia has two great explanations.\n\n > Some scientific explanations are so well established that no new evidence is likely to alter them. The explanation becomes a scientific...
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[ [], [], [], [] ]
88ki5m
what is gpg encryption and how does it work?
I tried using it once but got lost in the multiple directions given considering I'm not a super computer 'geek' (no offense intentions). I have something coming up where I will need to learn this and what it's about and how to encrypt a message or letter.
explainlikeimfive
https://www.reddit.com/r/explainlikeimfive/comments/88ki5m/eli5_what_is_gpg_encryption_and_how_does_it_work/
{ "a_id": [ "dwlamah", "dwlbi8w" ], "score": [ 2, 3 ], "text": [ "You generate a private key and a public key. The person encrypting should do so with the public key. The one receiving/decrypting should use the private key along with a passphrase. Kleopatra is an easy program to use to m...
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[ [], [] ]
1xfzyp
why do videos from middle-eastern countries always have someone repeatedly saying 'allahu akbar'?
I know it means God is greater, but why do they constantly repeat it again and again and again throughout videos?
explainlikeimfive
http://www.reddit.com/r/explainlikeimfive/comments/1xfzyp/eli5_why_do_videos_from_middleeastern_countries/
{ "a_id": [ "cfazmek", "cfb0nsc" ], "score": [ 9, 6 ], "text": [ "It means \"God Is Great\" and seems to be the words that fit for a number of occasions - victories, fearful times, in mourning, you name it.\n\nCompare to \"Oh My God!\" in the US and UK where we use it when we see something...
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[ [], [] ]
15w8xm
Can people be immune/resistant to norovirus and other gastrointestinal viruses?
Many people seem to fall victim to stomach viruses like norovirus throughout their lives, but there are also many people who, regardless of sharing bathrooms and living/working in close contact with other people, avoid contracting these viruses or suffering from them to the same degree. Why is this? (I have removed a ...
askscience
http://www.reddit.com/r/askscience/comments/15w8xm/can_people_be_immuneresistant_to_norovirus_and/
{ "a_id": [ "c7qerbg" ], "score": [ 2 ], "text": [ "With regards to your comment on \"higher stomach acidity\" do you mean higher relative to the average person, or higher relative to individuals on proton pump inhibitors? I'll leave this question to later once I'm clear on what you're asking. \n\...
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ygwiu
If you weigh a van filled with birds will its weight be different if the birds are all flying? Will the result be any different if the van had no roof?
askscience
http://www.reddit.com/r/askscience/comments/ygwiu/if_you_weigh_a_van_filled_with_birds_will_its/
{ "a_id": [ "c5vg5jb", "c5vgb7z" ], "score": [ 3, 2 ], "text": [ "If the van is closed (hermetically), its weight will not changed (it might fluctuate though, like when you jump up and down in a van its weight fluctuates, but on average the weight will not change).\n\nIf the van is open, i...
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[ [], [ "http://kwc.org/mythbusters/2007/04/episode_77_birds_in_a_truck_bi.html" ] ]
13azt9
why everyone is dressed up in paintings and photos pre-20th century.
explainlikeimfive
http://www.reddit.com/r/explainlikeimfive/comments/13azt9/eli5_why_everyone_is_dressed_up_in_paintings_and/
{ "a_id": [ "c72cim2", "c72clo0", "c72cqnn" ], "score": [ 2, 2, 3 ], "text": [ "There were no digital cameras or iPhones to take pictures. Photos were taken and developed by professionals and took relatively longer. As such, they were a lot more expensive and getting your photo tak...
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[ [], [], [] ]
5d1y97
why do devs with completely free apps, not make it open source?
explainlikeimfive
https://www.reddit.com/r/explainlikeimfive/comments/5d1y97/eli5_why_do_devs_with_completely_free_apps_not/
{ "a_id": [ "da14tf3" ], "score": [ 4 ], "text": [ "Usually, open sourcing something takes more work than not open sourcing it. If you're just doing something on a lark or to learn something, you generally don't want to bother putting unnecessary effort into it." ] }
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2r0aa4
If stars only fused elements up to Iron (Fe), then why can we find heavier elements in nature (Uranium)?
askscience
http://www.reddit.com/r/askscience/comments/2r0aa4/if_stars_only_fused_elements_up_to_iron_fe_then/
{ "a_id": [ "cnbq019", "cnbqw6z" ], "score": [ 14, 7 ], "text": [ "While the largest stars are only able to form Iron in their natural process, occasionally stars run out of \"fuel\" and collapse in on themselves due to their immense gravity and cause an explosion called a supernova. Durin...
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[ [], [] ]