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c3rnh1
what are the actual risks of talking about tienanmen square massacre in china?
[ { "answer": "You’ll get re-educated to be a more harmonious citizen in re-education camp if you have families that would make a fuss if you’re missing, if you don’t you’ll just disappear. \n\nThey actually talk about their version of the event in uni. The gist is: no protester die, many peace keeper die, there ...
null
1k5gy9
Why are rashes red in colour?
[ { "answer": "Increased blood flow. Histamines and other inflammatory agents which are released at the point of cell damage or an immune response increase the flow of blood to the area, making rashes red and hot.", "provenance": null }, { "answer": null, "provenance": [ { "wikipedia...
null
w86rh
Why is it that when I am eating cereal, and I have earbuds in, I can hear the crunch so much louder than usual?
[ { "answer": "The vibrations travel up your jaw to the ear bones. There's a brief [spiel](_URL_0_) that sort of explains the tie between the jaw and the development of the ear evolutionarily. You can look it up elsewhere for more info.", "provenance": null }, { "answer": "I have a bone anchored heari...
null
2isn7f
what's stopping me from taking a relatively large loan and leaving the country to live in another country?
[ { "answer": "literally nothing. A lot of people do just that. However, you are still obligated to fulfill your responsibility to your creditors and thus, leaving the country does not magically indemnify you of this responsibility. Furthermore, unless you actually die, certain kinds of loans can also be pursued ...
null
1rlukv
what is a "reasonable doubt"? i know what the legal definition is, but i want to know what i means.
[ { "answer": "Identical twin brothers are accused of murder. Their identical DNA was found at the crime scene, proving one of them did it. Neither will rat on the other, so there's no witness testimony. Absent other evidence, neither brother can be convicted even though it's obvious one of them did it because...
null
4kvefz
how can services like cloudflare filter out ddos traffic without getting a false positive from, for example, an article getting posted on reddit and subsequently getting clicked by 10 million people?
[ { "answer": "So I'm not the expert here, ~~Debbie~~ wait wrong subreddit.\n\nAnyway, the goal of DDoS isn't to bring down a server in the sense you and I usually think of it.\n\nLoading a webpage works like this:\n\n\"Hello, server at _URL_1_? Are you there?\"\n\n\"Yes.\"\n\n\"Hi, I would like the page _URL_0_\...
null
rmo23
How many trees (better yet, houseplants) do I need to plant to be 'carbon-neutral' at home? How about for the car
[ { "answer": "first a general remark: you must realize that planting trees, doesn't make your household carbon neutral.\ncarbon neutral refers to producing biofuels from biomass (like wood, energy crops, algae, ...). these biofuels can me burned to generate energy, to drive your car, ... in the process producing...
null
3jx4lh
How do laboratories contain such astronomical levels of heat?
[ { "answer": "It's always best to know about the scale of things. The 4 trillion Celsius liquid is formed by particle collision (apparently a photon and a lead nucleus). That means that it's at best atomic scale. So, despite the fact that it's really, really hot, it's also really, really small, so small that it ...
null
4mef5t
does shifting quickly up in manual car really save gas?
[ { "answer": "A really really good driver can save gas with good shifting, but 99.999% of drivers are not that good. I think the average driver would be hard-pressed to beat a modern automatic transmission.", "provenance": null }, { "answer": "The basic rule of thumb is for efficiency, drive in the h...
null
2b00jz
Why do humans have such bad backs/knees?
[ { "answer": "Because of technology, we're adapting in different movement patterns, positions, posture. You could say the advancing of technology has changed the way we do things e.g. prolonged sitting, prolonged standing, etc etc\n\nWe're designed to stay fit and flexibility. We have become so reliant on techn...
null
98rlpc
why is tesla having higher networth than ford or gm, when the former hardly produces a small percentage of cars than latter?
[ { "answer": "I don’t understand this either. Hype maybe?", "provenance": null }, { "answer": "The main reason is that the share price is based on what they are going to do in the future, not just what they are doing now.\n\nFord and GM are big companies who sell lots of product, but a lot of the ca...
null
yq317
why is the japanese culture obsessed with robots? more specifically humanoid robots?
[ { "answer": "I am not 100% sure if this answers it but here goes.\n\nWhen cartoons where first being developed to appeal to kids animation was super expensive and time consuming so people had to find a way to do it as cheaply and quickly as possible. Japan's animators found robots where very easy to animate bec...
null
7514cz
How realistic are Western movies/games?
[ { "answer": "The \"wild west\" is an invention of hollywood through and through.\n\nLet's start with those saloons. A typical \"wild west\" saloon is a large open space filled with tables with a bar at one end and wing doors at the entrance. In reality a typical bar in the old west would have been long and narr...
null
1vqwpy
why does my body feel "slanted" when i'm lying in bed when i'm drunk?
[ { "answer": "Because your balance perception is off because you're drunk.", "provenance": null }, { "answer": "the reason you are dizzy while drunk is that not all of your senses are working like they should. If you sit your tactile sense, inner ear and eyes are getting clear information. Once you s...
null
ytm9e
What is the least complex living being known to feel pain or any clear response to damage?
[ { "answer": "Depending on how you define pain, one of the simpler could be a type of [Cnidaria](_URL_0_), e.g. a hydra.\n\nThey have sensory neurons, and they're able to respond to damage. But I wouldn't say they can *feel* abstract concepts such as pain, since they don't have a brain.\n\nDisclaimer: I have no ...
null
291kxv
Why are anti-depressants typically just re-uptake inhibitors instead of actual doses of serotonin or dopamine?
[ { "answer": "From what I remember is that serotonin and dopamine won't be able to cross the blood-brain barrier. Also the body will just start breaking them down. So they won't be very effective in getting to the desired sites. ", "provenance": null }, { "answer": "When a neuron fires, it releases n...
null
17rrz0
If your brain releases melatonin when it gets dark, is it the opposite for nocturnal animals, and it releases when it's light?
[ { "answer": "No. Melatonin is released from the pineal gland into the blood during darkness, regardless if the animal is diurnal or nocturnal. ", "provenance": null }, { "answer": null, "provenance": [ { "wikipedia_id": "5632946", "title": "Shift work sleep disorder", ...
null
9eoxmq
During WWI & II (and/or in other relevant modern conflicts) how did belligerent powers actually make use of the industrial capacity of occupied territories?
[ { "answer": "It is well-documented that the Nazis (WW2) took over captured weapons factories and used them to turn out lots of weapons for use by the Wehrmacht. Examples include the FN-High Power, the Polish Radom, the FN M1922, the Norwegian Colt .45, and there are lots more. The Czech VZ 24 and VZ 33 rifles...
null
9re085
how did we end up with a silent k, of all sounds, in words like knight and knife?
[ { "answer": "Silent letters are the ghosts of pronunciations past. The word 'knight', with its silent 'k', and silent 'gh', is cognate with the German word for servant, 'knecht', where every letter is pronounced. ... The 'e' isn't pronounced, but it changes the pronunciation of the vowel by lengthening it.", ...
null
c7t2zi
Is there really a debate on the amount of people killed by communists regimes in the 20th century?
[ { "answer": "You might be interested in the historic debates around the Holodmor that I describe [here](_URL_0_). \n\nAs for the \"100 million deaths caused by communism\" - as far as I am aware, this claim specifically comes from the *Black Book of Communism*, published in 1997 by Stéphane Courtois et al. Whil...
null
ddwjbz
The Greek Gods and Jesus
[ { "answer": "Short answer, no. Long answer. Christianity was unique in that the miraculous birth story that is told of Jesus was through a virgin. But other than that, a miraculous birth isn't all that uncommon. In The Gospel According to Judas, Jeffrey Archer and Francis Moloney argue that the conception of J...
null
4o7kvr
why are there more bugs out at night?
[ { "answer": "Because they have a better chance of not being eaten by birds, most of which sleep at night. ", "provenance": null }, { "answer": "Many factors, such as cooler temperatures, evolving on preying on nocturnal prey species, predatory evasion, etc. Also artificial lights from light posts ar...
null
krp42
Tooth decay only because of poor dental hygiene or can genetics play a part?
[ { "answer": "I am not a dentist but my understanding is that genetics can definitely play a part. Inherited [amelogenesis imperfecta](_URL_1_) for example can cause [enamel hypoplasia](_URL_0_).", "provenance": null }, { "answer": "I've heard that health plays a role in tooth decay as well, and that...
null
6b5zcn
Why did the Abbasids revolt against the Umayyads? Was it because the Umayyads were hostile towards the descendants of the prophet(12 imams)?
[ { "answer": "Pardon me for asking but what does \"SAWS\" mean?", "provenance": null }, { "answer": "To begin with, the Abbassids did not claim descent from Muhammad. The Sunni definition of Ahl al-Bayt is broader than the Shi'a definition. Sunnis consider *all* of Banu Hashim and their descendants t...
null
i457j
Anatomically, what muscles/tendons/etc. move the jaw from side to side or front to back?
[ { "answer": "Side to side is accomplished by the [medial pterygoid muscles](_URL_2_) and the [lateral pterygoid muscles](_URL_0_)\n\nForward and backwards is accomplished by a couple muscles: \n\n* Forward (protraction) is accomplished by the [masseter](_URL_1_)\n* Backwards (retraction) is accomplished by the ...
null
17vfq3
what is a subsidy?
[ { "answer": "Very simply, a subsidy is when the government offers money to a group, usually corporations, to achieve various results. This can range from lower prices for the consumer, to help researching new technologies, to an effort to stabilize prices. \n\nA great example in the US is farming. As we all kno...
null
gj96e
Is radioactivity "contagious"?
[ { "answer": "Neutrons can transmute nearby materials to unstable, radioactive ones. This takes a lot of neutrons though, as is generally only seen inside nuclear reactors. For instance, the stable iron inside reactor pressure vessels can absorb neutrons and become radiative forms of iron.\n\n56Fe + n - > 57F...
null
5uea95
Can water freeze above 0C/32F with additives?
[ { "answer": "As I recall, anything dissolved in water will always depress the freezing point. In the case of the article you're most likely thinking about, the idea is to install wind power pumps that will bring water from below the existing ice surface and put it on top. This will work to thicken up the ice, a...
null
56799r
What are the causes for a hurricane of this magnitude? (Hurricane Matthew)
[ { "answer": "There were strong hurricanes before there was global warming, and Matthew is pretty typical for a Caribbean storm. It's not likely anyone could pin this one on climate change, but if there were some trend that was different over the course of decades, then you could look back and say maybe that was...
null
yd2v4
Why isn't Greenland a continent?
[ { "answer": "Basically it's arbitrary. Continents are decided based mainly on convention rather than specific criteria. Also Greenland is quite a bit smaller than say Australia. 2,166,086 square kilometers as opposed to 7,617,930 square kilometers.", "provenance": null }, { "answer": "It's pretty ...
null
13ictu
Explain CPT symmetry and the implications of this article.
[ { "answer": "CPT symmetry means that if you flip C, P, and time, all of them, the particle will behave the same. It doesn't behave the same if you flip just C or just P or just T. ", "provenance": null }, { "answer": "C, P, and T are all separate transformations. C is negating all charges, P is flip...
null
cyn8ea
Why did the muslims take so long to adopt the printing press considering how highly they value historical records and their sacred book?
[ { "answer": "Not to discourage further discussion, but you might be interested in [this previous answer](_URL_0_) from u/frogbrooks.", "provenance": null }, { "answer": "There's always more that can be said, but you might enjoy this previous answer from /u/Zooasaurus on [Ottoman Printing Presses](_U...
null
101ydp
how did newton figure out gravity?
[ { "answer": "The rotations of the planets were well known. however it was assumed that the orbits were circular. Newton invented calculus (though whether or not he was the first is a matter of debate) and proved that the orbits are elliptical not circular.", "provenance": null }, { "answer": "I'm go...
null
1cdeu8
why is it that when i watch tv recordings from the 70's, 80's or 90's the quality is absolutely terrible, almost unwatchable, but back then they seemed perfectly fine?
[ { "answer": "Compared to everything else at the time, they looked pretty much the same. Also, you're probably watching on a much nicer screen now.", "provenance": null }, { "answer": "The quality of the equipment you were watching it on was much lower, so not only were you used to watching lower qua...
null
7ouewn
What are your opinions regarding Martin Gilbert’s books of WW1 and WW2?
[ { "answer": "I read the WWI books by Gilbert, SLA Marshall, and Keegan about a decade ago. I enjoyed all of them as they offered quite different perspectives and focus. \n\nLooking at them as strictly operational histories versus a more \"war and society\" approach, Gilbert's work falls into the latter whereas...
null
1m81he
why sometimes paintings that look like a wounded chicken drew them are considered art and could be sold for millions?
[ { "answer": "Art isn't all about who can make the most detailed drawings, aesthetics are huge in it. A very detailed and beautiful landscape would fit in nicely with a traditional theme, however minimalist or abstract themes are part of a contemporary theme. \n\nThere is also meaning in the paintings. A well dr...
null
23u2u1
What caused the significant phenotypic diversity of Central Asia?
[ { "answer": "Central Asia has always been a contact zone between Caucasoids and Mongoloids. Indo-Europeans have inhabited the area for a long time, Tajiks are Indo-European speakers and also predominantly Caucasian phenotypically. Today's western China was once inhabited by Tocharians, who were Indo-Europeans, ...
null
6euilg
how did someone like duterte rise to the power in the philippines ?
[ { "answer": "It really comes down to the fact that the Philippines has had a massive problem with drug usage in the past several decades. Along with that is a prosperous organized crime epidemic. Rodrigo Duterte, while he was mayor of Davao, did manage to get rid of a lot of the towns drug problems.\n\nYes, he ...
null
mamn9
Why is it, that an infusion with artificial blood cannot develop itself into cancer?
[ { "answer": "Blood cells lack a cell nucleus (though that does not mean that they are prokaryotes. That term is used to describe cellular *organisms* without a nucleus, not single cells) and other important cell organelles (mitochondria, ribosomes, rough ER, etc...). That means that not only are they unable to ...
null
eo1czz
Can pyschopaths have traumatic disorders like PTSD?
[ { "answer": "Trainee clinical psychologist here. There's no current diagnosis of psychopath. That term, and sociopath, are a bit outdated and currently covered by antisocial personality disorder in the DSM-V (the manual used to diagnose mental health disorders).\n\nIt's a good question though. Theres no reason ...
null
cr53cd
What’s our early evidence for measuring horses in hands? Why has it persisted as the standard for measuring horses?
[ { "answer": "The hand is a unit of measurement that is used exclusively for the describing the heights of horses and other equids. Horses are measured from the ground to the top of the [withers](_URL_0_). One hand is equal to four inches. Although hands are expressed decimally, they are base four units. A h...
null
6mnu9k
What do we hope to gain or reveal through research and experimentation of quantum entanglement?
[ { "answer": "Some of the motivation is fundamental research. There has been much effort invested in conducting truly loophole-free [Bell tests](_URL_3_) as they establish that the non-classicality that quantum mechanics predicts in fact can be observed in nature. While the relation between entanglement, existen...
null
xo3rt
Can you easily break somebody's neck by twisting their head quickly, like in the movies?
[ { "answer": "I read this question answered a few months ago on here. Basically the top comment said that a person's neck muscles are super strong, so that unless the killer really surprises the person being killed, the person could tense up and fight them off. ", "provenance": null }, { "answer": "N...
null
2kin9h
Really small question about napoleonic french army jackets
[ { "answer": "Although I don't want to discourage others from answering, the forum on [The Napoleon Series](_URL_0_) has a number of reenactors lurking on it. ", "provenance": null }, { "answer": null, "provenance": [ { "wikipedia_id": "987790", "title": "Bearskin", ...
null
76y15m
If muslims were known as descendants of Ishmael in the middle ages, were they to some extent already recognized as some 'third' Abrahamic group prior to the birth of Mohammed?
[ { "answer": "Did Islam exist before the birth of Mohammed?", "provenance": null }, { "answer": null, "provenance": [ { "wikipedia_id": "30933488", "title": "Prophets and messengers in Islam", "section": "", "start_paragraph_id": 6, "start_character":...
null
3s34ly
what is sql? is it one of the simpler programming languages?
[ { "answer": "SQL = Structured Query Language.\n\nIt is a language meant for getting/updating data in databases. An example command (so to speak) would be\n INSERT INTO table(col1, col2) VALUES(val1, val2)", "provenance": null }, { "answer": "SQL is essentially (essentially being a keyword here) ...
null
21oco3
why isn't canada outrageously wealthy due to their landmass?
[ { "answer": "Cold. Too cold. Transportation is tough when it's too cold. ", "provenance": null }, { "answer": "Actually one of Canada's biggest hardships is over coming the vast empty space that separates us and working together. For example, I live in a city of 80,000 people, and to get to a maj...
null
2r69bo
how are baitcar operations legal? what makes it not entrapment?
[ { "answer": "Entrapment is when an officer convinces someone to commit a crime they otherwise wouldn't. When bait cars are set up, there's no undercover cop standing there telling them they should break in. They're doing it purely on their own volition.", "provenance": null }, { "answer": "Entrapmen...
null
33leh7
As we understand black holes, how does gravity outside the event horizon affect items inside the event horizon?
[ { "answer": " > Let's say that there's a Jupiter sized planet orbiting around a black hole. Would items inside the event horizon be affected by the planet outside it? \n\nYes\n\n > Also, would that not also affect where the event horizon was? Wouldn't the gravity pull from the planet slightly move the event ...
null
1eppy1
Why do royalty take the style of their first name (ex. Queen Elizabeth)?
[ { "answer": "They do *technically* have last names -- descendants of Queen Elizabeth II have the surname Mountbatten-Windsor.\n\n[\"For the most part, members of the Royal Family who are entitled to the style and dignity of HRH Prince or Princess do not need a surname, but if at any time any of them do need a s...
null
5l7n3u
why do you have to "charge" glow in the dark stuff?
[ { "answer": "The light is charging the molecules inside. Think of it like this, compare the \"activation\" to winding up a wind up toy and when you stop and let it go it is slowly releasing the energy you built up. Instead of a toy walking it is releasing a constant glow. ", "provenance": null }, { ...
null
1s0zdb
why are probabilities called densities?
[ { "answer": "Density refers to how tightly packed the elements of a set are. Density as the trivial relationship between mass and volume follows this.\n\n\nObserving probabilities as the relationship of chances and incidences and mapping them to a unitary scale gives rise to the idea of distribution—how great a...
null
9kit58
how do drugs like kamagra and viagra affect the body?
[ { "answer": "Your question was so interesting that I looked it up. Thanks for making me learn something interesting\n\nI'll try to explain Viagra (active ingredient sildenafil). Wikipedia says:\n\n > \n\"Sildenafil is a potent and selective inhibitor of [cGMP-specific phosphodiesterase type 5](_URL_0_) (PDE5)...
null
3c5ktk
why aren't the joint chiefs five star ranks?
[ { "answer": "Because the joint chiefs don't individually control everything. They each have control in their respective branches, but they still have to coordinate with each other.\n\nOn the flip side, the president can't be expected to have the knowledge necessary to issue out advanced, detailed orders.\n\nSo ...
null
57cl1j
Who was the first recorded Chinese person to visit or live in the United States?
[ { "answer": "My first thoughts of this is that there probably were no recorded records for the first Chinese person, because there was a robust international trade in goods and services by the time of the Pilgrims. People traveled throughout the world for tea and spices. So, it would make sense that at some p...
null
f21pdq
why is it best for someone with frostbite to warm up slowly?
[ { "answer": "It's not about you warming up too quickly. A very cold hand is also a numb hand, so you can't tell how hot the water you're putting on yourself actually is, so it would be very easy to burn yourself without realizing it until you've done serious damage. \n\nMeanwhile it's not really important to ...
null
2s1ina
how did the states get their shapes?
[ { "answer": "Sometimes it was geographic boundaries like rivers or mountain ranges. Sometimes it was done via treaty with other countries (and they stuck when the state borders were formed). Sometimes they were just chosen arbitrarily (especially where the straight lines happen).\n\nObviously there are more det...
null
12dbjj
Is there an evolutionary reason that most animals separate solid and liquid waste?
[ { "answer": "Animals don't separate their wastes per se. Solid waste is the result of processed food, liquid waste is the result of blood filtering via the kidneys. So the two different waste types come from different systems, and at no point are they really the same thing. Feces are from the beginning of the c...
null
26ehxp
why don't reboil water? or is it ok?
[ { "answer": "Completely false. There's nothing wrong with boiling water a million times, other than the fact that you won't have much left.", "provenance": null }, { "answer": "Random fact if you boil water to much it can become deoxygenated this is an important factor when making cups of tea. The m...
null
dpab8t
Did Aircraft Carriers in World War II carry spare aircraft?
[ { "answer": "Yes, many aircraft carriers in WWII carried spare planes, though the type and number varied quite a bit by the type of carrier and the individual navy's doctrine (and the availability of spare planes, of course). \n\nFor example, Nagumo's carriers at Midway (_Akagi, Kaga, Soryu_ and _Hiryu_) were n...
null
40hj41
On nutrition labels, why are sugars and carbohydrates listed as two separate entities?
[ { "answer": "To explain why, one first needs to understand the distinction between carbohydrates and sugars.\n\n*Carbohydrates* - molecules composed of carbons, hydrogens, and oxygens. Another term more commonly used in glycoscience is \"saccharide\", but the two are more or less synonymous. While most people w...
null
1sa1kh
if i bought a self driving car, would i need a drivers license?
[ { "answer": "California is still in the process of creating laws regarding this matter, so I can only give you a speculative answer.\n\nYou would need a drivers license to operate a self driving car in case the system malfunctioned. With that same line of thought, it's plausible that laws will govern that there...
null
fejovi
how are we able to hold our breath for so long? how do our vitals still receive oxygen?
[ { "answer": "Also remember that if you stopped breathing right now, there is enough oxygen in your blood for you to have little to no brain damage for 10 minutes, *as long as your heart keeps pumping*. Sanjay Gupta wrote about this in the CPR chapter of his book Cheating Death. This is why CPR works even if you...
null
3qy7k8
why can't windmills based out at sea have a tidal power element at there base to allow for tidal-energy too ?
[ { "answer": "Because that would merely cost, while only increasing energy production by a very small margin.\n\nWind turbines are placed in areas with high wind, and ideally on sandbanks to reduce installation costs. The chance that this matches with a place where tidal forces can be gathered cost effectively, ...
null
9et3zh
Why do some birds have forked tails?
[ { "answer": "Upturned wing tips increase lift in smaller wings we now use this in aviation as the upturn cuts the wingspan by a third and reduces drag. \nThe forked tail makes the bird more agile at high speed in the air hope that helps ", "provenance": null }, { "answer": null, "provenance": [ ...
null
2qrtf0
why are universities treating education like it is corporate business?
[ { "answer": "You named them. More faculty, more housing, more classrooms. Universities are very expensive to run. Qualified professors aren't exactly a dime a dozen, and most universities I've seen are running low on space to expand, since they were either built in a major city or a city has grown around the...
null
33aamx
Math and operational warfare: how much and which type of applied mathematics was employed in tactical operations during the ww2?
[ { "answer": "By World War II, most naval vessels mounting guns large enough used GunFire Control Systems involving radar rangefinders, mechanical gun directers, analog/mechanical fire control computers, etc. such as the American Mk 37 GCFS. Most were mechanized, so little manual calculation was required.\n\nTan...
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6cdapf
Is it true that one pound of body fat is equivalent to 3,500 calories?
[ { "answer": "No. Fat contains roughly 9 Calories per gram, so a pound (454 grams) of fat is about 4,086 calories. However, that 3500 number is a common approximation, because most people don't lose pure fat when they are eating a caloric deficit. It's common to lose some muscle mass, etc. at the same time. Losi...
null
a9xec9
How did pre-Colombian societies in and around the Caribbean deal with the "Hurricane Season"
[ { "answer": "There's always room for discussion, but perhaps the section [Natural Disasters](_URL_0_) from our FAQ will answer your inquiry.", "provenance": null }, { "answer": null, "provenance": [ { "wikipedia_id": "19847316", "title": "October 2008 Central America floods...
null
e7acv9
how does the measles virus wipe out your body's "memory" of immunity to other viruses and why is this not common in other viruses?
[ { "answer": "The virus has a proclivity for immune memory cells as targets for infection. This causes the death of the immune memory cells from the action of the virus itself and from elimination by the healthy aspects of the immune system in fighting the infection. This widespread destruction of the immune mem...
null
196lm5
running, sprinting, and jogging. what's the difference?
[ { "answer": "Sprinting is all out pedal to the metal so to speak ...jogging is maybe half speed... its to get your heart rate up and be able to endure the exhaustion of physical activity ...if that doesn't help google it ", "provenance": null }, { "answer": "Running is what you'd call the action its...
null
28o942
What family ruled for the longest length of time?
[ { "answer": "If we look at this as skeptically as possible, accepting only the most well-attested historical records, the Imperial House of Japan is the best bet. The Solomonic dyansty in Ethiopia claims to have ruled earlier, but a lot of their claims are very poorly documented and they don't even claim to hav...
null
3roln1
asian keyboards
[ { "answer": "Most of them look pretty much like U.S. keyboards.\n\nYou usually type the Japanese or Chinese characters phonetically with standard letters. Then a list of possible matches appears where you are typing, and you can click or arrow to the correct choice.\n\nMost Japanese characters also have Japanes...
null
6dizz7
why is it easier for me to remember numbers that are hyphenated (social social security numbers, phone numbers) but hard to remember a long stretch of only numbers?
[ { "answer": "This is probably due to a memory process called \"chunking\". Basically, your short-term memory can hold around 5 to 9 pieces of information at a time. When you see a string of numbers, such as 457389321, your short-term memory is trying to hold 9 separate pieces of information. When you break t...
null
1ctgvm
Would surface area impacts gravitational pull ?
[ { "answer": "Gravity is a dependent on mass, not shape, so it doesn't matter how much of the surface is exposed. We're pulled to the center of the Earth, not the surface. The surface just keeps us from falling to the center of mass.", "provenance": null }, { "answer": "keoAsk is correct, there is no...
null
3ndcye
Would it be possible to communicate from inside a black hole by changing its rotation rate?
[ { "answer": "When you are on the inside, you contribute to the total mass of the black hole. You've brought whatever mass you had outside to now be part of the black hole. The same is true of angular momentum. You can add to the angular momentum in some way but once you are inside the event horizon, that angula...
null
42jv13
why is it when a child is learning to speak, the most common constant expressed is a "w"-sound?
[ { "answer": "It's because it's a really easy sound to make. Children learn easy sounds like /m p b w/ etc. first, and then they learn harder sounds later on.", "provenance": null }, { "answer": "Not an expert in any way, but I would assume it has something to do with how easy the \"w\" sound is to f...
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dp4wm4
Was Qing imperial policies in Xinjiang, Yunnan, Tibet, etc. comparable with European colonial policies? Was the Qing Empire a "colonial" empire?
[ { "answer": "I don't really know enough about \"colonial\" policies in general to compare them to Qing policy in Tibet (it should be noted that China itself as a Qing imperial possession in the strictest sense). I mean, the \"colonial period\" lasted five centuries and was vastly different based on the colonial...
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4wiwid
how were 5v and 12v decided on as the "go to" voltages for so many electronic devices, specifically computers?
[ { "answer": "Transistor Transistor Logic gates operate on 5Volts. Logical 0 is up to....I think 1.5volts? Logical 1 from 3.5-5v\n\nNot sure where 12v is from.", "provenance": null }, { "answer": "Combination of safety and industry standards. You can also run smaller gauge wire and smaller com...
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1k3aia
When did adult baptism go mainstream.
[ { "answer": "After the Reformation, the only sect of Christians that practiced adult baptism were the Anabaptists, as indicated by their name. This aspect of their practice caused persecution by Catholics, Lutherans, and Calvinists. \n\nIt moved towards the mainstream with the Methodists in the 18th century, an...
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4atckz
because natural selection is not happening to humans with modern medicine, what does it mean for the human race in the near and distant future?
[ { "answer": "Medical and technological advances will heavily outweigh the potential evolutionary benefits humanity as a species may have possibly gained over thousands of years due to natural selection. As such, pretty much nothing. The only cases where natural selection would play a part are in extreme cases, ...
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3i1zwq
Are North and South poles of a planet or magnet interchangeable?
[ { "answer": "The right-hand rule sets the convention, which says that the north pole of, say, a bar magnet is the pole from which magnetic lines diverge and the south pole is the pole into which magnetic lines converge. We could have just as well defined the north and south pole the opposite way. (It would requ...
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28kxzm
Is the vacuum of outer space fundamentally the same as the empty space between particles like electrons and proton? Or are they different somehow?
[ { "answer": "An atom is not mostly empty space. This is a common misconception. The electrons, protons, and neutrons that make up an atom are not little solid balls separated by vast expanses of empty space. They are quantum objects that act somewhat like waves and somewhat like particles. In an atom, the elect...
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1l6icg
What would happen if you antibacterialized your digestive system?
[ { "answer": "This happens frequently on very strong antibiotics. It causes digestive disorders and colonization of the gut by unfriendly microbes, notably Clostridium difficile (C. diff), which causes severe diarrhea, is hard to disinfect and is easily spread between patients and healthcare workers.\n\n_URL_0_"...
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38gfiw
why do zambonis need to be so big?
[ { "answer": "To hold more warm water so they can clean/smooth ice more effectually. \n\nHow whole internal parts works I am not 100% on. But playing hokey for 10 years you tend to notice things. I know it picks up the ice it scrubs off and melts it for more water to use. As well as it needs weight so the tires/...
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1ekjei
How did Pangaea form into one island, given the randomness of plate tectonics?
[ { "answer": "In fact supercontinent cycles are a fairly regular occurrance as far as we can work out, with a periodicity of about 250-500 million years. _URL_0_\n\nThe driving force for plate tectonics is subduction of oceanic crust - in other words the closure of oceans. The natural product of that is bringing...
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edo6go
why does sleep deprivation make you see spiders/bugs on your peripheral vision?
[ { "answer": "I'm pretty sure you are asking why sleep deprivation causes hallucinations, well, sleeping is important for your body, but it's the most important thing for your brain, because during a sleep cycle the brain gets rid of toxins that have accumulated. If you don't sleep these toxins don't go away and...
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3p4e7c
How did Romans and Greeks treat the ideas of war and peace?
[ { "answer": "There were people who have a lot of different viewpoints just as you have right now in our society. There was also a lot of discussion on war and peace as is now the case. \n\nAn interesting shift took place in the general discussion due to the coming of Christianity. War and the pacifist moral of ...
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6r3hhp
what determines a person's sense of humor?
[ { "answer": "Mostly psychological. When a person has good sense of humor, it generally means they are happy, socially confident and likely to have a healthy perspective on life. But this has exceptions because humor has a dark side. There are people who use self-defeating humor; also humor is used to critici...
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p0ho5
Putting something in orbit
[ { "answer": "The speed required is ridiculously fast (about 7 km/s).", "provenance": null }, { "answer": "For something to be in orbit for any significant length of time (more than a few minutes) it has to be able to maintain a fairly constant speed perpendicular to the Earth. Even at the height a w...
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2qu9s5
how does time lapse video with the different angle work? does someone slowly move the camera to a different location to create that smooth movement?
[ { "answer": "jop, stepper motors and stuff, actually many people build those themselves because its really not dark magic. _URL_0_", "provenance": null }, { "answer": "/u/YMK1234 is right. You just build a rig that will move the camera, usually powered by an electric motor, and have it move incredib...
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brdb9e
I keep hearing Pro-choice People say harsh abortion laws will “take us back to the Dark ages”. How acceptable/unacceptable was abortion in the Early middle ages?
[ { "answer": "Answering this question is difficult, not least because record survival from this period is scanty and one-sided. The most prolific writers in late antiquity and the so-called ‘dark ages’ were theologians. If we dig deep enough, we might find some secular laws related to abortion in the context of ...
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3m9u9s
how does russia maintain and sustain #2 military in the world with economy smaller than brazil or italy (#10)?
[ { "answer": "By spending a larger portion of their money on their military. This is how North Korea keeps a large army on a small GDP, they don't spend as much on food. It's all a matter of choices.", "provenance": null }, { "answer": "No other country manages to spend anywhere close to the truly ...
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2ss82x
Did royalty ever get an inkling that birth defects was a cause of marrying their family members?
[ { "answer": "People tend to think that the European royal houses were long, unbroken lines stretching back into the mists of time, aka \"the Middle Ages\". In fact, that's not the case at all, and intermarriage between royal houses was rarer -- and was not repeated, close cousin marriage -- until only a few hun...
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6mi7rz
How long did NASA truly expect the Mars Rovers to function?
[ { "answer": "All components, and the system as a whole, are calculated for a given reliability. Usually it's like 95% for the expected mission duration. If it does survive to this date as expected, odds are it won't fail right the next day. So the probabilities may be like 95% for a year, 85% for two years, 75%...
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28vedr
why do you hear a whoosh noise if you put a glass on your ear?
[ { "answer": "Blood flow in your year. I guess you can hear it because it is amplified in the enclosed space of the glass.", "provenance": null }, { "answer": null, "provenance": [ { "wikipedia_id": "352733", "title": "Glass harmonica", "section": "Section::::Forerun...
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6djj8t
how a noun can become a verb, like google or photoshop?
[ { "answer": "People just start using the word as a verb and it becomes popular.\n\nThere's not much more to it than that.", "provenance": null }, { "answer": null, "provenance": [ { "wikipedia_id": "12270491", "title": "Wuvulu-Aua language", "section": "Section::::M...
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5rw7yt
how do electronic ph sensors work?
[ { "answer": "An electric pH meter is essentially just a voltmeter. An acid solution is essentially half of a battery, so the pH meter brings the rest of the battery along and measures the potential difference between the two leads on the probe. Once you've determined the voltage of your \"battery\" the Nernst e...
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7tgzkc
if light slows down in water, how does it speed back up again when it comes out?
[ { "answer": "There's a way to think about this problem that was--IIRC--in Stephen Hawking's *A Brief History of Time*. \n\nImagine a big famous actor walking through a room. They travel at a constant speed that we'll call A. The actor always moves at speed A, no matter what. When the room is empty, they're able...
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2u4bw9
Can two things ever truly 'touch'?
[ { "answer": "Yes, because touch and contact are words defined by our experiences, which means that it isn't an issue of scientific nomenclature. ", "provenance": null }, { "answer": null, "provenance": [ { "wikipedia_id": "366663", "title": "Body language", "section...
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