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1tvwzu | Why "crazy people" have that distinctive look to their eyes | In many psychotic individuals, the wide eyed look is because of their intense anxiety levels. It's more than just the eyes though. In someone psychotically agitated, you'll see facial grimacing and body postures indicating stress or aggression as well.
The scariest patients are the ones that have a flat affect, meaning they just have a blank stare all the time. Though many of them are lost in their own world and harmless, some are not. They are concerning because i can't judge their propensity towards violence at any given time.
Source: IAMA Psychiatric RN | 7b3eadd6-377a-4b1e-bbdf-587c4d636bd7 |
790u7d | The NASA twin study. I know what it is. Just explain their findings. Like I'm 5. Years old. Thanks. | There are a lot of effects on the human body from being in space. Micro gravity affects your muscles and bones, there are weird particles that pass through your body (including your eyes and brain, which cause [strange flashes](_URL_0_)). It's hard to study the long-term effects of being in space, though, because everyone is a little different. Are your bones deteriorating because of the microgravity, or is it because of genetic predisposition for osteoporosis?
This is true of any study that attempts to look at long-term effects of something. To account for as many variables as possible the best subjects to use for those studies are twins. Because they're genetically identical, you know that whatever genetic predispositions they have will affect both. So in this case, if they *both* get weaker bones, you know that it's not *just* the microgravity. But if one gets weaker bones and the other doesn't, then you know it's something to do with being in space (or not, as the case may be).
However, with astronauts you have another problem: you can't just take a random twin and put them in space. You need a *lot* of specialized training to be an astronaut, obviously. And you can't even just train one. The rigorous training and strictly controlled diet of astronauts are variables that could affect the outcomes of the study. This astronaut has stronger bones than his non-astronaut twin, but is that because of his diet that includes a lot of calcium, or strength training that went into being an astronaut?
Conveniently, NASA has one set of twin brothers that are both astronauts! They've both had very similar experiences as part of NASA. One is spending a year on the ISS, the other is staying on the ground but also getting the same diet and exercise regimen - basically as much as they can keep the same with him on the ground. They'll study the differences between the two astronauts to study long-term effects of being in space.
This is an important study because going to Mars would require longer space missions than we've done in the past. No one has stayed in space that long, really, and we haven't had good opportunities to study them and the effects of that. So they're doing this study to better understand what we need to prepare our astronauts for if we're going to successfully send a team to Mars. | c7f28425-9452-4562-8369-f1047df92dd2 |
1ay4wb | What is the point of money? | It helps to understand the barter system.
Before we had money, you would travel to a central trading post a few times a year to get things you couldn't make yourself. You would haul things with you to trade - maybe a stack of animal pelts, or jars of jam, or sacks of wheat flour. You would negotiate with the people at the trading post to get what you needed - six pelts for a sack of salt, two dozen jars of jam for a bolt of cotton cloth. Each person had valuable goods, and they traded that value.
A problem happens when you can't easily trade for what you need. A shoemaker is a very useful guy to have around, but he can't really trade a whole pair of shoes every time he wants to buy a meal. If I was an innkeeper who needed boots, I might make him a deal for credit - we might agree one sturdy pair of boots is worth 30 meals. The Innkeeper might keep a ledger saying who has meals coming to make sure it stays fair.
Still, the Innkeeper's ledger doesn't do the shoemaker much good if his roof is leaking. The shoemaker needs to trade with someone to repair the roof, which is fine if the repairman needs boots. If not, maybe the shoemaker could trade the repairman his credit for 10 meals at the Inn? If he can pass his credit to the repairman, then everybody gets what they want.
This is a basic kind of money - it's backed by the Innkeeper, who says that the credit is worth a meal. It's worth hanging onto even if you don't plan to eat at the Inn, because you can trade it to other people for goods or services. That way, you can trade with someone even if you don't have anything to trade that they want.
Eventually, it doesn't matter if the Innkeeper even provides the meals anymore. People use the credits as markers for trade - 3 credits for a pelt, 2 jars of jam for a credit. Nobody eats at the Inn, so the money is only backed by what people agree it's worth. As long as everyone is free to negotiate, the credit is still worth exactly what people believe it is worth. | a1af51e6-b3ed-43e8-b724-73e787eae1de |
3kvf2v | Why does charge build up in a cloud? | Bits of dust stick to the water or float through the air. The dust and water rubs against each other and every time they do, some electrons get passed from one to the other. Then the particles wander off again before the electrons get passed back. This goes on enough, and *tons* of electrons get thrown around until it builds up a very very large negative charge. The result is lightning: the charge gets explosively released. Sometimes this means from one section of cloud to another, or into the ground. | b340b84a-fea5-41c1-9821-f389f43f89ac |
lehsx | the hypothetical turtle on an island in the sun question? | I *think* what you are taking about is a test from the book "Do Androids Dream of Electric Sheep" on which the film "Blade Runner" was based.
If so, the test aims to distinguish humans from androids ('replicants') through their emotional response to questions requiring empathy.
_URL_0_ | 972cb589-0d4c-4294-bf40-0487fdc1bbb7 |
91fex6 | how does a home equity loan work? | A home equity loan is a loan that is based off the difference between the value of the house and the current balance of the primary mortage.
If you paid $50,000 for a house that's worth $75,000, you can get $25,000 in equity loans. Subsequently, if your house was worth $75K when you bought it and it's now worth $135K because reasons, you can now get that much more in your equity loan.
In theory, you don't have to wait at all to get a loan. If you sign on the dotted line for the $75K house for a $50K mortgage, you could turn right around that day and get a $25K equity loan. you just have to have the equity in the house to get the loan. | 26ce441e-17da-4150-bdd5-1ad86af15a36 |
6s1tut | In English, what is the rule for the use of “An” or “A” | An is used for words that start with a vowel sound.
Examples,
An owl, an hour, an eight, an apple, an onion.
A is used for all others. | e83da6c6-6504-415d-bc69-2558b8420f58 |
6igjw4 | Why do we have two small nostrils and not one larger nostril? | It's usually not noticeable unless you sniff harshly, but one nostril is usually more open and free-flowing than the other.
The nostril that's closed usually swaps back and forth after several hours throughout the day. When a nostril is more closed, it's swollen, because the blood vessels inside the nose are swollen.
During that time, your immune system attacks all the nasty stuff that came into your nose. It's harder to breathe when that happens. But your other nostril is wide open and maximum air comes in.
This combination of having one closed nostril and one open nostril is a super efficient way for your body to both clean the nasties and breathe full air at the same time. If it was all just 1 nostril, then every few hours you would have difficulty breathing.
Air breathed through the nostrils are combined in the back and flow into both longs. One nostril does not lead into one lung. | 3d2a15a6-fc36-4acb-a50d-20011ef52a4a |
z10qg | Border Gateway Protocol (BGP) | I stumpled across this subreddit and saw this and said, what an excellent chance for me to jump in for once.
I am a network Engineer.
BGP is a very, very complex routing protocol that the entire internet pretty much runs on.
I don't know how familiar you are with routing protocols, but there a lot of things involved. Primarily, you have the administrative distance, that dictates which route a router will decided based on the protocol
SO for an example, RIP has one of 120, OSPF of 110, and a static of 10. Internal BGP (routes within your Autonomous System number) have it of 200, and external of 20. The lower the number the lower the cost, and that router will choose that route.
Then there are metrics, which are variables you can sorta play with to get the outcome of your routers routing decisions. In BGP there are many of these, and I can't even begin to go into all them, mainly because I still don't know all them.
SO how is this so complicated?
You have router A B and C. They are a triangle, simple routing protocols can find routers to each other and even passive routes if active ones fail. But now let's talk the internet.
Now you have to create a sure fire to advertise your routers and etc correctly so that anywhere in the internet knows how to get to you and vice versa. To get to router E, you must take path D, then C, then B. But if router C goes down, take route F, then G, and H. But if router D goes down take Route R, and then S. But if route R goes down take X, and F, etc etc, just turning that triangle into a pentagon creates a headache, no imagine the giant rat fuck nest that is the internet.
There is no router god that overlooks all this, typically you manage what you know of, and there will be some higher echelon that knows more, and on and on, but you can see where the confusion comes in.
BGP is incredibly powerful, yet extremely fragile, and at times AMAZINGLY DANGEROUS. A man who knows what he's doing, and a man who doesn't know what he's doing, could, potentially take down the internet in some big ass regions of the world.
Hope this helps. | 11315f36-3cae-4977-9b7e-8709034ce433 |
8qqob8 | Why do car rims appear to be rotating backwards after a car accelerates? | /r/flooey is partially correct. That is the reason wheels appear to move backwards on film. This effect can be leveraged with a stroboscope [for an odd illusion](_URL_0_) even in real life, by imitating the film effect and only allowing your eyes to see individual 'frames' in time.
However, as you probably noticed (and I assume are asking about), this happens in real life as well, under continuous lighting. Excitingly, we don't really know why this happens! There are [two competing theories](_URL_1_) at the moment. One is basically that visual perception actually does act like a camera, and only processes small snapshots at a time.
However, later experiments found that this explanation fails in several circumstances. The hypothesis proposed by those researchers is that this effect is instead to do not with snapshotting of the entire visual system, but a kind of ersatz snapshotting to do with propagation delays in the particular subsystem that does motion detection in the brain (Reichardt detectors). | e7c57134-cd3d-4fde-9836-4c3ac3076b60 |
5inzg9 | How the heck do authorities determine who started a massive fire in the middle of the woods somewhere? | The first arriving units will most often be at the fire before it gets large, so they can relay to the investigators where the fire was and how big it was when they arrived on scene.
Fires will also leave lots of clues as to how fast and hot it burned but also the direction that it came from. There are origin indicators like needle freeze (pine needles that freeze and point in the opposite direction of where the fire came from), charring on trees can tell you a lot depending on how intense the fire was when it burned the tree. Grass can fall back towards the origin in a low intensity fire. There could be no soot on a large rock on the opposite side of where the fire came from. Those are just a few examples.
As to finding how the fire started they have to look at the origin of the fire which is why you look for that before you start looking for how. Once at the origin, depending on how the fire was started it could be hard easy or impossible to determine. A hot start, where someone just holds a lighter or similar flaming material to the fuel and then takes the lighter and flees is hard to prove. But often times fires don't durn so hot when they first start, depending on many factors, and there could be evidence left behind as to an ignition source. Most accidental fires you can find out who did it either because they confessed or they weren't trying to get away with it so there are witnesses and more evidence. Also most arsonists don't just start ONE fire, they start many. And once there is a known arsonist working an area reports become more general so you can charge him with more fires knowing that you have some that are definitely him and some probably aren't but can't rule him out for it.
And for big, expensive, deadly or suspected arsonist fires there will be multiple expert investigators.
Source: I'm a fireman that took a couple week long classes on origin and cause determination. Wild land fires aren't really my thing but I'm just relaying what was taught to me.
Edit: spelling and a parenthesis | 466f7484-5e56-4c1d-baa5-41148665238f |
1rv694 | How do film/tv productions handle deaths of actors? Examples? | Usually it leaves them scrambling. I know when John Ritter died they actually had to write that death into "8 Simple Rules". | 0c1d4e6f-03af-4f05-b114-ad92d3ba74e7 |
4hdmlp | Does the Sound Increase in Real Life when Someone on Television Increases the Sound? | The volume control on your laptop or speakers essentially controls the loudest volume you can get - anything that tries to be louder can be distorted. But anything quieter than that is possible.
So what might be happening in the movie is that the radio might start at a quarter of the maximum volume level. When they show him turning the dial, they also increase the sound of the radio to half, or three quarters, or full. So it is getting louder, although it can only get up to a certain point. It wouldn't be possible to get your earbuds to be as loud as a rock concert, for example. | 4ed3d6be-03af-4b8a-8542-4ba8796cb01d |
2umj9j | What would happen if all the countries wiped all the debt incurred by and owed to each other? | Not an expert in the topic but I have some knowledge
Debt isn't necessarily a bad thing as it represents a flow of money. This is why the average lifestyle in America is comfortably more lavish than those of in China. This is made possible because Americans are in better position to take out large loans and pay them back in the future.
If all the debt were to be wiped out then that would mean banks would lose a very high percentage of income.
Heres where my knowledge stops as my train of thought has been limited to what I know. | 3e6eef2b-bd39-453e-a7e9-cf7dbfea14ff |
2kx0wl | How is complimenting a woman on the street considered street harassment? | Part of the issue is that like many things in life the difference between something being nice, acceptable, and annoying has to do with how often something happens. If you don't see another car on the road for an hour it can be a relief to see one, a few cars are okay, and a lot of cars results in road range. In the video she got roughly one comment every 5 minutes. If my day was interrupted every 5 minutes by someone wanting my attention I'd find it difficult to get anything done or even be able to think.
Another aspect is that the comments are mostly seeking attention. Some of them were requests ("Can I have your number?") some were comments which are said loudly enough to try and provoke a reaction ("Nice ass") and some were instructions ("Smile"). When I'm approaching a person, I look at body language, make eye contact, and then talk. Shouting at someone, trying to get their attention when they are busy, or making demands of them all feel unnecessarily aggressive, yet that's precisely what most of these "compliments" are. They aren't compliments, they are demands for attention.
There are other examples I could use -- such as comparing this to harassment by paparazzi, unsolicited phone calls, or stalking. However in some ways it's simpler: US supreme court justice Louis Brandeis argued that there is a human "right to be let alone", and this video suggests that with the frequent persistent demands, this right simply doesn't exist for women in many places. | 1205928c-18bf-4074-b910-1fea87ca7cee |
1ldlac | What is fake meat made of and how do they get the texture to be so similar to real meat? | Soy burgers = soy protein. (dont eat too much soy: hormone mimickers). Texture is naturally kinda 'meaty'.
Myco burgers = mycelium. That's what mushrooms are grown from. They can't call em mushroom burgers, because mushrooms are the fruit the mycelium would produce. The mycelium is just a really fast reproducing cell that grows readily on MANY MANY substrates, usually best at a certain temp and humidity. -We will literally NEVER run out of a cheap protein source because of this invention (lofted mycelium growing- hot air blows up cloud of mycelium, which colonize lofted in host matter, usually in a hot steam environment.. It literally colonizes in a matter of minutes. - voila: mass food - more protein than steak per gram and no fat).
Finding a good mycelium was they key for this to be useful. So, basically, after a lot of trials, they finally found a mycelium which had a texture very similar to a hamburger. (Monsanto funded most of this).
I used to be interested in solving the worlds food problems, until I found out the problem isn't lack of food but rather infrastructure and bureaucracy.
Fake shrimp and such is referred to as surimi- basically ground up other fish and stuff.. I've seen some made from vegetable pastes and flavored. Usually not so good..
;) | 2b7c0904-f28c-4f24-9f0a-4b561de70ebb |
2x44pp | Why is it sometimes hard to find something that is right in front of our eyes. | Human eyes are way better at detecting moving objects than resting ones. Plus, a change in perspective may present the object in a better contrast/less obscured by other objects. | 39ab77c4-19bf-42c0-93fd-10d058c2fa94 |
2dqfaf | Why doesn't the body produce oil like the face does? | Actually your entire body produces the oil, but since your face is usually dryer (being in the sun for example) those glands work harder, not to mention think of how much you touch your face throughout the day, transferring more oil. Sometimes, certain foods etc will kick the sebaceous glands into overdrive, that's how acne happens. And acne can indeed happen anywhere - ever seen back acne? | 9bf437cd-172a-4357-9225-d400d2541fc1 |
lpf57 | Dash cameras in Asia? | Yeah, a lot of cars have dash cams which record the last 5 minutes, continually recording and saving whilst deleting anything older than 5 minutes old. When an accident occurs, the camera can either automatically detect something has gone wrong and continue recording beyond the 5 minute limit, or can be manually told to do so. This makes it a lot easier if the accident gets into court and it isn't immediately obvious whose "fault" the accident was. | 06d79c9b-bb93-4956-ac90-ec7e5463e946 |
1jok76 | Why do some people get brain freeze? | As long as it doesn't touch the roof of your mouth, you won't get brain freeze. | b7a1a3bb-7b93-4fc2-a095-af91dde8cea1 |
4f848k | Why is second day chili better? | The acids in tomatoes, peppers, and onions take time to break down carbohydrates (beans) and proteins (meat). So overnight the beans and meat absorb more of the delicious spicy flavor. | 628c2389-bab3-4ffb-83ae-0c828af63e38 |
5kgjw0 | How does the _URL_0_ door knocking audio clip do such a good job of making it sound like the audio doesn't come from your headphones? | Ha, had the speakers on when I played that audio clip and the cat **freaked** out. Apparently that knock knock fools animals into thinking someone's at the front door too.
Your brain determines the location of a sound's source by a few different factors. Namely, distortion differences between each ear, and delay in which ear hears the sound first. Technology has gotten good enough that with proper equipment it can re-create those effects and trick your brain. We usually use the term "binaural" as in "Two ear" to describe the effect.
One of the most famous examples of binaurual audio is the "Virtual haircut" clip _URL_1_ where they demo a technology designed to create the effect. Lots of ASMR artists and other people do it too, one popular device these days is [a 3Dio twin mic setup such as this](_URL_0_). With two microphones and extremely accurate recreation of the human ear shape (it affects how sound bounces about), you can recreate a whole room's soundscape effectively. | c02f47a2-349b-45fd-81e0-214fcddc9133 |
1zgwa3 | Computer/TV Screen Size Pricing | Easier, yes, in the sense that the assembly requires less pricise equipment. Not necessarily cheaper, though, because of the material costs. | 4e026cc4-4d62-4223-b372-2aaf190424a5 |
4ggr01 | If you have no sense of taste can you feel the heat/spiciness from something like a pepper? | Yes. Capsaicin (the chemical responsible for the spiciness of peppers), interacts with neurons, not taste receptor (although taste receptors are similar to very specialized neurons) so they would still feel the heat | 90a34954-d1ed-4218-8ce1-276e7bf066b3 |
1qcnpv | Why can we only use ~0.35 volts of batteries? | The notion that voltage and capacity are the same thing is where you've gone wrong. A battery will supply a certain amount of energy (usually measured in milliamp-hours^* ) over it's lifetime. But it will maintain roughly that 1.5V starting voltage for ~90% of that life. Only as it begins to die will the voltage drop. So while it seems to you that the voltage tells you how much capacity is left in the battery, that's not really the case. And what you're defining as "dead", let's remember, is just that the voltage has dropped below a useful level for the device you're trying to power.
* - Strictly speaking milliamp-hours aren't units of energy, but it's assumed that current is run over the standard voltage of the battery which in your case is 1.5V. By convention, all battery capacities are measured in this way. | 050416c0-a18a-4d8f-b52e-b53db897bbab |
8ig2qt | Why do people think Yellowstone will explode and destroy the earth, but not worry about Hawaii's volcano eruption? | Imagine you're filling water balloons.
One of them has a hole that lets out the water about as fast as you are filling it. You could stand there all day and be fine. That's how Kilauea erupts.
The other one is huge. It is also intact. Eventually, it will burst and soak you. That would be a Yellowstone eruption.
Obligatory edit:
Thanks /u/arcmokuro for my first gilding. I didn't expect the classic water balloon analogy to blow up like this. | 57434d71-e9ec-47b3-87ff-d1e1eed44268 |
6fjklq | How does cutting down trees to plant other vegetation for the purpose of cultivation (such as avocado farming) contribute to global warming? | When you cut down highly developed forests to replace them with cultivated land you're seriously lowering the amount of CO2 that can be absorbed.
A big tree that is several decades old will take in WAY more CO2 than several seedlings that are planted to replace it. Additionally, all of the undergrowth that is in forests absorbs CO2 but that is all removed for farming.
Further, a lot of the time what's done is called "slash and burn" which means that the forests are chopped down and the debris is cleared away via a controlled fire, once again adding CO2 (and other harmful chemicals) to the atmosphere.
Also, removing well established plants will significantly increase soil erosion and while that may not directly contribute to global warming, it certainly is detrimental to the environment. | 004dc81e-d175-4a78-9dab-402fd327a8fd |
4t4ycc | Mattress Sizes? | It's called twin because a long time ago you bought two of them, one for each person in a husband/wife partnership. You only slept together to make babies, you sinners! Then along came the Full which was meant for two people (though no room to move!). Queen was a luxury: they added 6" in width and 5" in length to a full so you could damn well sin all night! A king?? You heathens now get the length of a queen but add 16" to the width. You could have devil-orgies in those things (which is why I sleep in a king). | 45e2b6a8-9dd0-43f4-9de2-963194b0f9ea |
5jhpn6 | What happens to Lactose when ingested by Lactose-Intolerants? | So, from what I've understood in the past, people who are lactose-intolerant aren't able to break down lactose. Their body doesn't produce enough lactase, which is an enzyme that breaks down lactose. So, depending on how much lactose is taken in, it usually is broken down by bacteria instead in the gut. This causes a bunch of side effects like, nausea, bloating, gas, and stomach cramps. | c703b183-b428-48fb-851c-c6ef68d2a345 |
3tkfny | If Helicopters need tail rotors to stabilize themselves from spinning, how can turboprop airplanes have only one rotor and not spin in circles? | On a helicopter the main rotor blades are the wings, a plane has fixed wings that use the air to resist the torque of the prop that's trying to make the plane roll (this is also why single prop driven planes roll to one side faster than they can to the other) | 4eb49787-b3c8-4182-bb1a-3a434d3998f1 |
3f8ade | What is the difference between an air-conditioner and a "marine" air conditioner (commonly used on boats)? | Caveat - I mess with boats but I'm not expert or pro. In general marine equipment is made with more corrosion resistant materials,such as stainless steel. The A/C on my boat exchanges the heat in the cabin air into water that flows through the other side of the heat pump, so this is an air/water heat pump where most home units are air/air heat pumps.
Also some or most marine units are 12 Volt DC power, possibly also 24 volt. I think some few are powered directly off the engine via a 'fan belt'.
The reefer on my boat is three way power - 120 VAC, 12 VDC, and propane. I suppose this would be possible in A/C but I've ever heard of this. | 6e20f359-a895-4b42-8ed9-03b9853ad6e0 |
1yz7y3 | Why do people bother keeping savings in banks/currencies which are potentially unstable? | I see two reasons:
1. In most European countries you need a residence permit to open a bank account. In other words, you must live in the country where you want the bank account. Some countries, like Switzerland, allow foreigners to open bank accounts without a permit. However, the banking fees are high for such customers ( > 800$ per year). Unless people have substantial amounts of money ( > 100,000$) the fees will erase their savings. As it happens, many people in Ukraine are not very wealthy.
2. It is difficult. You need to go abroad, speak a foreign language, spend significant amount of time and money. Most don't bother. | fd7657de-24b9-4267-bdb4-4b8c26db1039 |
90cyb3 | Why does water freeze from top to bottom? Deep in the ocean it’s below freezing, why doesn’t it freeze? | There are several reasons. The salt in the ocean lowers the temperature needed to make it freeze. Currents stop the ice from bonding, and if Ice did freeze, it is less dense and floats. But the main reason is the pressure, especially in deep water. To freeze, water needs to expand. Deep in the ocean, the pressure from the water stops it from being able to expand. | 54df9c32-25cd-40f1-aeb3-6f1e1125237b |
19kskq | how they catch digital pirates who use hotspots or do they? | Normally, They don't. If they actually want to track down someone who is using a proxy, they will be able to; but for something as harmless as pirating(relative to say, hacking a company's system) it is not worth their time and money just to find out who you are.
Torrents from a hotspot are also not easy to trace back to the user, unless they have a way of identifying you(e.g you're at a hotel, and their internet asks for your room number). A lot of hotspot providers would(atleast in theory) attempt to prevent people from torrenting on their networks, otherwise, they do run the risk of being accused of illegal downloads. I'm not too sure of exactly how the copyright law side of things work though.
Off the top of my head, i can remember atleast one case where a guy using mcdonald's internet was arrested for spreading computer viruses, based of the fact that he used his credit card at the store and they had somehow managed to find out exactly which computer was responsible, however, for pirating purposes, its not worth the trouble. | 221dc054-d5dd-4e8b-8505-7cbd2f91715a |
1jah2c | The voting rights of citizens in the District of Columbia historically differ from the rights of citizens in each of the 50 U.S. states. Why can't the U.S. just add an amendment to fix that right now? | Because politics quickly becomes political. Currently D.C. is extremely Democratic, so Republicans don't want 2 new Democratic Senators. If the situation was reversed it's likely that the sides would quickly flip and Democrats would be blocking the amendment. | 7e3b2b22-8424-4b81-a25a-799150449841 |
2cimvd | Why did it take so long to invent the printing press? | Tske into consideration the literacy rate.
Most people could not read and had no reason to.
Necessity is the mother of invention, that is a true idiom.
There wasn't a need for it.
As was stated, the Chinese invented movable type a few centuries before Europe.
But we did have related items. The Romans had stamps wood blocks, which it technically the basics of the press. They just didn't need it in mass numbers. | 6c439d74-6dac-4070-a16c-bf6245e65daa |
2tss90 | I've been reading up on nukes. Did the Nevada nuclear tests have nuclear winter? Why or why not? | Nuclear Winter is not a local effect resulting from an atomic blast, but rather a hypothetical effect from lots of nukes going off. The theory is that the nukes would kick a lot of soot and dust up in to the air, blocking out the sun. The blocking out of the sun would result in lower temperatures since the sun can't heat up as much of the Earth anymore.
Some of the effects are based on similar effects felt when a large volcano goes off. Mt. Pinatubo in the Philippines went off in the early 90's and we only saw a slight drop in temperature (1 degree F). | 6f77789e-97c9-412c-b896-0d01d3dce6ce |
3c99e4 | How come cars are able to go up to 220 km/h but highways only allow speeds of up to 110 km/h. Wouldn't it be wiser to have cars max out at 110 km/h-ish and reduce the engine capabilities? | How long do you want to take to accelerate? Merging onto the highway in a reasonable time takes far more power than maintaining a constant speed. There are plenty of 1.0 l cars for sale in Europe. They take about 17 +/- seconds to reach 100 kph, but they are very fuel efficient. No one would buy them here in the US because it would be frankly frightening to try to merge onto our freeways in a car that slow. | 47dc0d51-e723-46db-ab1e-3af56362cc41 |
6hk74n | Is it ever possible in the future to have matching finger/thumbprints? | The idea that everyone has a unique fingerprint isnt really scientifically proven. There is a real possibility that you and someone else currently living have identical fingerprints. | f2dcd270-0bac-4cf0-9053-3af1e12269f2 |
1hfibf | How a military can overthrow a government? | The people with the guns stop doing what the president says, and they use their guns to do what they want. That's basically how it goes. | 75441718-7b63-416c-acd5-c802a4452729 |
3lqf1p | How do we go from binary codes to basic programming languages? | The lowest level instructions in a computer are the instructions of the CPU architecture. This varies between CPUs but there's two main ones currently: x86 used by Intel and AMD processors, and the one used by ARM processors.
These instructions usually look something like "MOV 1, 2" which might mean to take the number stored in memory location 1 and copy it to memory location 2. Or you might have "ADD 1, 2, 3" which adds the two numbers at 1, 2 and puts the result in 3.
When you hear about binary being the lowest level in a computer, it's just a binary encoding of these CPU instructions. So MOV might be 001 and ADD is 010, then the memory locations are represented as binary numbers after the type of instruction. When you hear about a 32-bit or 64-bit processor, that's how many bits each CPU instruction is. | 2e21aaab-a21b-4e27-9a7f-7d781c24e90a |
2c7hbe | why does spicy food stay spicy when it comes out the other end? | Spiciness isn't a flavor, it's a reaction to the chemical capsaicin, which irritates any tissue it contacts, not just your tongue. This is also why the area around your lips gets sore while eating wings. | ae140bcd-3b55-4d62-9e31-110071b8d3e0 |
2383nl | Why do posts on reddit not start on 0 (what's the purpose of allowing one to vote for oneself)? | To reward you for making a comment even if no one else does. | 56af69f5-3907-4930-940e-4eb130359785 |
8q7obo | if you light a lighter in front of a TV, why does the reflection show 4 tiny rainbows around the flame? | This is to do with, not the display itself, but the layers of diffusers that make up the backlight behind the display
An LCD TV consists of a backlight and an LCD panel. The backlight's job is to produce an even spread of light across the display. You first have an array of LEDs, but those LEDs are point sources, and you don't want lots of bright dots. So the light has to be spread out. They do this with sheets of plastic etched with fine lines. These lines bend the light and spread it out - but only in one direction. If you only had one of these sheets, you'd have an array of lines, one for each LED. So instead they use many sheets, each sheet with lines at an angle to the one beneath. With enough of them, the light is spread evenly.
It is these fine lines etched into plastic that produces those rainbows. Each line reflects the light of your lighter when the angle is right. You get a spot of light from each line, which makes a line of light stretching away from the reflection of the lighter. But the lines are close enough that you get interference - as the angle increases, the distance the light has to travel between scratches increases, and you find places where, for one color of light, the distance the light travels is exactly one-half wavelength, so the peaks of the light waves line up with the troughs, and cancel out. When you cancel out one color of light, then you only see the other colors.
This is the same effect that gives CDs and DVDs their rainbow appearance.
And this explanation is way too long. | 0e38c5d8-0491-4565-ae73-cf5099d430dd |
4njezi | How does copyright work with references? | US copyright has a Fair Use clause, which a minor reference like the ones you are mentioning fall under. You don't need to pay royalties for something like mentioning "I saw something like this on Star Trek once!" or "This is like Episode 79 of the Original Series, Turnabout Intruder! They got bodyswapped!"
As to when you cross the line of fair use, that's subjective and really you have to use your best judgment.
_URL_0_ has more info. | 789c5b9d-b03e-4a9d-9491-809feb1de960 |
5hnbhw | Why does China take claim to Taiwan? | Before the 1930's the Island of Taiwan was part of the nation of China. During the 1930's China suffered a civil war with many factions, the most prominent of which were the communist party(CPC) and the Government(KMT). This civil war spanned world war 2 and reached a physical conclusion in 1950 when the Communist party physically wrested control of the mainland. The KMT retreated to the Island of Taiwan and has remained there in exile ever since.
The big issue about sovereignty comes down to the United Nations. As one of the main victorious nations of World War 2, China was granted a seat on the UN permanent security council, alongside the USA, UK, France and USSR. However this seat was granted to the KMT government, not the Communist party of China. So when the KMT were exiled, they still retained the official recognition in the UN as the official government of China.
The communist party however, having established pretty total control over the entire mainland, considered themselves the rightful leaders of China, including the Island of Taiwan that the exiled KMT government now resided on. The US government was initially disinterested until the Korean war came along, and they realised that they needed a card to play against the communist chinese, so sent the 7th fleet to help protect Taiwan.
This stalemate continued until 1971 when Communist China was given the UNPSC seat instead of the exiled Taiwanese government under UN resolution 2758. Since then most nations have adopted the attitude that Taiwan is technically officially part of communist China while also treating Taiwan as its own nation in everything but name. As CGP grey once put it, "The united states sometimes sends aircraft carriers to protect one part of china from another part of china".
I hope this ELI5 is insightful, the Taiwanese situation is a very complex one from a political and cultural one, and is a major part of 20th century history. | b2d982a8-bdf8-44c6-9fbd-99af58f09b38 |
3jeoha | Why is the word 'cunt' such a taboo word in the U.S.? | People have made it so. Words can be given such power based on how they're used in the culture. I remember when Austin Powers 2 came out (it was called Austin Powers 2: The Spy Who Shagged Me), and that was seen as quite vulgar for British people. In the US, Shagged is a cute word (like using Poop in place of the word Shit). Just remember that it is how it is taken, not how it is intended. You could be using cunt like the Aussies do in friendly conversation (referring to their friends), but someone who isn't used to hearing that can still take offense to it. | 4f4af532-a2a7-4788-aa3f-dd73f061e757 |
8bvsvh | why is it so easy for people to start working out regularly but it’s hard to stop eating certain foods or cutting back? | Human being are designed to eat as much food as they possibly can, because in nature food is a whole lot rarer. We crave salt, fat, and sugar. This is a problem today because we have industrial farming and society. When he had to hunt down all out food ourselves it was a lot harder to eat enough to actually.make us fat. But now that all we have to do is take a trip to the grocery store and pick up a 4 lb bag of M & Ms, it's easy to be fat. We | a7acb3a5-2c4f-4e99-b521-1fd93ea4185d |
2kqsrc | Why is the USA drinking age set at 21 when in most other respects you're an adult at 18. | In the 60s and 70s, the US had a **lot** of fatalities as a result of teenage drunk driving. Waaay more than any other country did.
Really, there were two options available to them: raise the drinking age, or raise the driving age.
I think they made the right choice. | 26bb237f-06b8-40ee-afad-5bf4fc5a0831 |
2lhad1 | Why do I not smell perfume I've sprayed on me but other people do? | Why don't you see your nose? It's within your vision.
Your brain filters out your nose, because it's always there, and likewise, it filters out smells that are "always there".
The phenomenon is called [sensory adaptation](_URL_0_), this is the brain caring less about constant stimuli. Olfactory neurons also fire less frequently. | 3eacfdd2-d001-40d4-b326-4b27f1425eb1 |
48q6wy | How does a two headed reptile/siamese twins work? How do they move their bodies assuming there are two brains? | Typically each twin controls a different part of the body. Like the twin girls Brittany and Abigail Hensel. They give the appearance of being one body with two heads, though they have two of each organ above the waist. They have two arms, each controlling one. And from the waist down, they have one body, with each controlling one half. So each controls a leg, for example. There doesn't appear to be any part that both of their brains controls. So they coordinate with each other so that they can walk, but they each have their own body parts they use. In some cases of animals with two heads, only one head "works". The other head doesn't seem to have any reactions to stimuli so it's vestigial. | dfd03f60-c74f-497c-af26-8fe7bdc169e1 |
1ofr1c | How do human voices work? What makes our voices seem so unique? | Finally a question that being a voice major has equipped me to answer! (Avoiding the proper terms for parts because that's what Google is for):
Air passes from your lungs in between your vocal folds (roughly right behind your Adam's apple, that's a front projection of the mechanism that protects it). They're quite tiny and produce a tiny sound. Cartilage around them can manipulate/stretch them to make them thinner (higher sound) or thicker (lower sound). That small bit of sound that they make while vibrating is amplified by the natural cavities in your head: your throat, your mouth, and your sinuses. The way that you manipulate those cavities (especially the mouth) produces the other qualities to the sound, such as the volume, nasality, and very importantly, sounding like different vowels or voiced consonants. Some consonants are produced with only air (for example, "s").
I would assume the reason why everything we say sounds different from other types of sound is that we train ourselves constantly from an early age to pay attention and sort patterns out of speech sounds versus other types of sound. | a9c20bf2-876c-4f78-aa65-cd3f3fb61b36 |
2bixaj | why aren't AK47's an "accurate" rifle | 1. AK-47's distance between the sight and post is very short which makes it so that for longer ranges, it is extremely difficult to line up an accurate shot as you are more likely to be misaligned with your eye to the sights.
2. It uses a relatively low velocity round, meaning it arcs more and spends more time to get to the target, making it deviate more from environmental conditions
3. Its feeding mechanism uses very large and heavy moving parts which reduces accuracy dramatically from recoil.
4. It has a more significant recoil upon firing due to its type of ammunition, making subsequent rounds less accurate.
5. It operates on a lot looser tolerances, while making it more reliable, also reduces its overall accuracy.
6. [Its gun barrel flexes more than other guns during recoil.](_URL_1_)
Compare that with [this](_URL_2_), Or [this](_URL_0_)
7. The barrel isn't inline with the stock, making recoils want to push the gun upwards. | e621625b-c261-4c4e-af15-f4349827a0c5 |
271vef | Why can I not remember what happens when I'm drunk? | Memories enter the brain first as short term memory, that is then transformed into a long-term memory.
This is evident because the majority of short-term memories that we experience are lost before they ever make it into what we will call "long-term" storage.
When alcohol is consumed it affects your ability to take short-term memories and transform them into long-term memories.
This is why you only may remember small bits and pieces of the night, these are the select short-term memories that were allowed to settle into long-term ones without the interruption of alcohol. As the level of alcohol drops, the number of memories that make it into "long-term' storage increases. | 198f45c4-2e9d-4e07-a2d2-7cb09a2a609b |
38uslm | Why does having noise in the background (TV, music, etc.) make me feel safer when I'm home alone? | Your ears are sensitive through a wide ride of volumes. When it is very quiet, you hear faint noises you are unaccustomed to, which can be disconcerting. Background noise hides those sounds with ones more familiar to you, restoring your comfort level. | 2917ade8-5aeb-4be4-8c79-00e3a87ace0b |
6045of | Isn't the freshwater we have to work with just going in a cycle? How are we losing fresh water? | When the water ends up in the oceans, it slows down the cycling a lot. Water in aquifers (the stores under the ground that we access when we use wells) and water on Earth's surface are the cheapest to use. We have been either polluting these (surface) or using them too fast for new water to filter in. We have also allowed a lot of water to go to the ocean(storm water runoff from developed areas) , rather than slowly go into the aquifers through the ground. So the result is we are using aquifer water faster than they are getting refilled. When that water is depleted, all water will become more expensive. We will still have it, but it will either be salty, polluted, or far from where it needs to be, and all of the fixes for this cost money.
Sorry if this isn't too coherent, I haven't finished my first cup of coffee for the day. | a576b0d6-8e12-4bf2-a25a-23258ba76812 |
25wg9s | Why is there such a large Insane Clown Posse (Juggalo) following? | A lot of it is because the group tries to make its fans into a "community" (Juggalos). Like, fans of a band like, say, the Black Keys, are just people who happen to like the Black Keys. But ICP specifically encourages fans, "Hey, dress up like us, be like us, be part of something," and then the fans encourage each other to do it too. People like that. They like feeling like they're part of a group. It's the same kind of thing with Lady Gaga and her "Little Monsters," just a different type of music. | 1deea1fb-d242-43eb-97ab-b4fc31b36f67 |
627lss | What's the best/safest/quickest way for a relatively skinny but unhealthy guy to get big using weights (w/ or w/o protein powder)? | The gist of it is to lift weights and eat a **lot** of food. A program like Stronglifts is great for beginners.
Protein powder isn't magic, it's just a cheap and easy source of protein. Most people find it easier to drink a protein shake than to eat a bunch of steak. It's probably healthier than other sources of protein because of the amino acids it contains, specifically L-cysteine. You should definitely use it. | 7420138c-d92f-4341-a8d4-439c4ac052fb |
17geb3 | Why metal at room temperature feels cold while, say, fabric at room temperature doesn't | I believe it has something to do with the rate at which heat from your body is transferred to the material. Your body is hotter than both the fabric and the spoon, which are at the same temperature, but the spoon conducts the heat at a faster rate and so you feel it as being colder. Please correct me if I am wrong or missing some details. | 2f19b8db-ca72-451c-a05f-d461c3cd399f |
49vbyw | A neighborhood cat comes to your home and you feed it. A day/week later, other cats appear at your house looking for food. How did the other cats find out that you're a food giver? | Kitties talk among themselves, just like humans. They may not make a sound, but they do communicate ... and follow each other around.
Seriously: you can/should check out [Alley Cat Allies](_URL_0_) for all sorts of info about hungry kitty visitors. | 634d0710-9de4-43f3-8a93-646c4b94b39d |
1xrsvm | Why do southern states freak out over a little snow? | There is essentially no infrastructure to deal with snowfall in southern states because it happens so rarely. Roads are not salted or plowed so they are covered in ice, and nobody has snow tires or much experience driving in snow. It is sort of like how everyone up north has trouble with a little heat wave where it gets over 100 F; nobody has A/C and are not acclimated to heat so it is a problem. | 8853aeea-4732-4452-a559-b6063cc9b130 |
4r24rs | What is the origin and meaning of "Strange women lying in ponds distributing swords is no basis for a system of government." | It's a quote from Monty Python and the Holy Grail. The "strange woman lying in pond" is the Lady of the Lake from the Arthurian legend.
_URL_0_ | 3214bfb4-787b-4fb1-a3d5-d7f3259a2c9d |
1ql953 | What are those bastardly little tongue sores you get from eating too much salt or sugar, and how do you get rid of them? | The condition is called aphthous stomatitis, or commonly, canker sores. They are NOT inflamed tastebuds. Rather, they are small ulcers (areas of inflamed, healing tissue) that are characteristically painful and confined to the mucosa (soft tissue) of the mouth (including surface of the tongue) by definition. There is no cure, but many over-the-counter drugs are sold that can mitigate the pain caused by them.
This question is by no means explained (moderators, hello?). Rather, the pathogenesis (how it develops) of an aphthous sore is still unknown. I couldn't believe it, but apparently this is an area of relatively active research. [This](_URL_1_) recent review article provides some nice context.
[This question](_URL_0_) has been asked many times before. Doing a quick look-over, answers have been repeatedly unscientific and certainly not in any real laymen-speak. | af5d87f4-5110-4519-893e-c78847c8b211 |
4gtubr | Why are swearing words related to genitals and/or sexuality? | Swear words come from things we consider taboo or distasteful. In English-speaking society, we have a lot of taboos surrounding sex, even in this day and age. We also put a very high level of importance on hygiene, so words relating to waste and where they come from are also taboo.
Certain words automatically make your brain think of a subject in a more intense way than others. A colloquial term vs a scientific one. This is true for pretty much anything, even if it isn't a swearword -- sweat vs perspiration, for example. When it's a topic that's taboo, that word becomes a swear. When it isn't, it moves back into innocuous territory. | 3ae95a9e-425a-4f26-a655-bfb0a547ea32 |
15epd0 | How does a bird know to not sit on its unfertilized eggs? | They don't...They will sit on plastic eggs. The hen eventually gives up and deserts the nest and will try again...Yeah,the eggs rot if something like a squirrel, or another bird does not eat them before they go bad.
_URL_0_ | 21113c59-0f0d-4e6d-96f9-b1f08917ae33 |
5ww96o | Why does Basic Income Decrease "Werkgelegenheid" and is this the same metric as "Job Opportunities"? | > isn't employment rate supposed to reflect how many people are voluntarily employed compared to unvoluntarily employed?
If you consider those who need the money to live but if they didn't wouldn't work as "involuntarily employed" and not part of the employment rate, then your employment pool would be near zero and almost everyone working would be involuntarily employed.
The employment rate is a measure of how many people who are trying to find work can find work. This isn't perfect because maybe if unemployment is high some people stop looking, but it at least weeds out those who could never be employed by available jobs.
If more people feel they need to work in order to have a comfortable income for their family unit then your labor pool expands. If you make sitting at home more viable for collecting income then your labor pool can be expected to shrink.
> So, by that account, that means that between 1945 and 1960 employment rates were judged by how many first earners were employed. And now, they seem to be judged by how many first as well as second earners are employed.
Women aren't "second-earners", Jesus Christ that is sexist. If you have a woman and a man earning in a family then you just have two earners and perhaps they could get by with one or the other income. Neither needs to be primary and secondary.
> Wouldn't that just mean that the involuntarily unemployed has more, rather than less job opportunities? Wouldn't that reduce the pressure on the labor market?
More people working means the labor market has more to choose from. But it isn't like you can just double up on the labor market from both sides, squeezing the supply of labor to raise wages to secure labor and also taxing them to support basic income to nonworkers. Prices will skyrocket and foreign investment will plummet.
We don't even have to do crazy math or speculate about how these tendencies will balance out in the end. There is a basic principle at work: People working creates value. If there are more people in your economy working to create value then there is more value to go around.
We might argue that one hypothetical economy has everyone employed at low wages and buying products at low prices, vs a second economy where only one person is employed at a ridiculously high wage while everyone else is paid a low wage through taxes, buying products at ridiculously high prices. I would argue that whatever voodoo magic you propose to make the low wage entitlements capable of purchasing the high cost products would never work, but it is difficult to prove that one way or another. What is obvious is that if everyone but the one guy is sitting around not doing work then *shit isn't getting done*. | 58501d9b-f2a3-43b4-8cba-8890e44e6b38 |
w4mgs | How does Task Manager's "Set Priority" work, does it increase performance significantly, and how/should I use it? | Windows is built for multitasking. The 'Set Priority' feature is intended for managing what processes have a higher priority for resources (CPU) than other processes.
Applications set to normal will go 50-50 on the resources with other running applications (when demanding resources).
It's better practice to close all resource demanding background applications while using another resource demanding application.
If your CPU is a bottleneck in gaming, setting the game process to 'High' may help. Though if nothing in the background is demanding a lot of resources while playing, you probably won't notice a difference. Do not use 'Realtime' as it could starve out other critical system processes and stop responding to input.
--------------
Since there is apparently a lot of 5 year olds in this thread:
Imagine you have a lego set with a limited number of legos. You want to build 3 separate objects but there aren't enough lego pieces for all 3. So you determine that **1** of the objects will get **High** priority over the other ones and get as many lego pieces it needs (as long as it needs less than the total amount of lego pieces). The other **2** lego objects you decide are **Normal** priority and will split the remaining lego pieces half-and-half.
The **2 Normal** priority lego objects don't get enough lego pieces to be fully functional, but the **1 High** priority lego object does.
Now, if you didn't have enough lego pieces for even the **1 High** priority lego object, it too would be incomplete and not fully functional.
-----------------
* Lego objects = Applications
* Your priority determination = Windows
* Lego pieces = CPU resources | 3feb6f59-63df-487f-af3f-489072fc11cb |
3vral0 | the Venezuelan election results | Not the exact answer you're looking for, but might provide context if you'd like it - _URL_0_ | 1a022843-ecc4-40f8-8cbb-967db0e7e9d5 |
3ceo9f | How can Pewdipie make $4M a year? | Most of his money would come from Youtube views and advertising. Having as many views as Pewdipie gets would certainly net you a lot of money from Youtube. | 6d08e47a-a386-4846-a74a-824f33722958 |
3otc7z | Where exactly is a woman's G-spot located, and how do you find it? | Straight in, stick to the top, two o clock (yes always) until about the second bend in your fingers, if you've hit your knuckles that's way too far. It all generally feels the same to you but it has sort of an interesting texture. So I know perhaps you've always been told to do the "Come here" motion but it's actually okay to be a little bit rougher than that, nearly all the nerves are located outside and in the clitoris. So use your dominant hand for entry and place the other hand palm down thumb towards you, gently but firmly across the lower pelvis. Use your two fingers with dominant hand to move entire fore arm in a controlled vibration sort of motion. Check with female on pressure and intensity. Use clitoral stimulation at your discretion. Hope that makes sense! | 6bf90fb5-41e7-455a-81a3-6967b200cf74 |
2wt5wm | Why do we hear static from radios and TV's when there's nothing being broadcast? Shouldn't we just hear silence? | Because there isn't nothing there.
Every spectrum is full of random noise from stars, radioactive decay, all sorts of things like that. It's just terrestrial broadcasts are so much stronger that it overwhelms the random noise. This is why when you start reaching the edge of the coverage area for the station you're listening to, it starts getting more and more static-ey and doesn't just go from "fine" to "nothing." | db18f6c5-d456-4d8d-8c25-466ec0aac142 |
3sx35l | why you can't put metal in the microwave but nothing happens to the metal that it's built from | You can put metal in microwaves, which is a lot come with racks, you just can't put metal with sharp edges/points such as forks and aluminum foil. As for the interior, most microwaves have their interior painted to prevent these issues. | 1c9c2452-76bc-4657-847a-d5f4673d1982 |
1s3m9h | How do street lights know when cars are there? | There's a couple ways that traffic lights know there are cars there.
The first (and probably most common) is sensors under the road. They use coils of wire to detect when something magnetic (like the steel in a car) passes overhead. You can actually usually see them if you look at the lanes, there will sometimes be a 4ish by 6ish square that's visible from the surface.
Other traffic lights use cameras to actually detect cars with image recognition, but there are still pretty rare and are generally put in to do double-duty as red-light cameras or traffic monitoring.
There's a few around that use infrared motion detectors (like motion lights or supermarket doors) but I actually haven't seen any in a while, they might be phased out.
As far as the boxes on top (and this is a guess) it may be part of a system emergency vehicles use. In some cities, emergency vehicles emit an infrared signal (like a remote control does) straight forward when they have their sirens on which will tell the light to turn that way green and all others red. | 0c6bb95b-0f0e-4b31-8732-1a2832976bbc |
17akbb | Why do people age? | Nothing is perfect. Even our bodies, the result of billions of years of evolution from the simplest single-celled life forms, begin to fail after awhile. All of the things that make our body run, our stomachs, hearts, brains, kidneys, will eventually stop working. But the main thing that causes people to age is their own DNA. All DNA has little bits on the end of it called telomeres. Every time DNA is copied (this happens every time cells divide) the telomeres get shorter and shorter. The good thing is that telomeres don't have anything important in them, so it's ok. But after the telomeres are gone, the important parts of the DNA start getting lost. This causes many bodily functions to slowly stop working like they are supposed to, and eventually stop working at all. | 3a4b5080-9eb1-49bf-993e-7571a0fe7e46 |
1kl1mu | The size of the universe. | There's more than one way to measure cosmological distances.
One way is to use what's called the "lookback distance." It's just the distance measured in units of time. If light from an galaxy has been in transit for a billion years, then you can quite accurately say that galaxy is a billion years away. (This is sometimes phrased as a billion *light years* for sake of clarity.)
The other way to measure distances is to imagine that you could somehow magically stop time and stretch a very long ruler across the distance you're measuring. This is called the *instantaneous proper distance.* It's used much less often, because it's not a *useful* number to calculate. You *can't* stop time or stretch a ruler across those kinds of distances, so the number you get from that kind of calculation is really only a particularly obscure type of trivia.
So the radius of the observable universe is both about 14 billion years and about 46 billion light-years. Both statements are equally true.
We know the age of the universe because we can look at the temperature of the sky and see how much it's cooled since the end of the Big Bang, and we can look at the rate of metric expansion and see how it relates to pressure.
And you're thinking of metric expansion quite wrongly. It's not that there's a wall out there that's moving away from us. It's that *all distances in the universe* vary with time. Not because things move, but because the *geometry of the universe* is itself a function of time. Right now, it's estimated with quite a high degree of precision that all distances in the universe are increasing at about seventy kilometers per second per megaparsec. | 1c204fd7-1e09-42ba-aa42-ec85bd4ec14a |
1wzq91 | Why do school hours not match working hours? | That means teachers would go home at 7 or 8pm, school buses would have to contend with commuter traffic, and students would be walking home in the dark most of the time. | b28918c2-4811-46cc-96bd-17ac76097fd8 |
11hg3m | Why do dogs go absolutely crazy after getting a bath? | I'll probably get another NO BLATANT SPECULATION response from the wannabe mod we have lurking here, but here's what I've found looking around for you: **Nobody actually 100% knows the scientific reason, but dog experts have been able to put together some good guesses based on what we know about dogs.** Many of them have actually been listed here, but I'll put them all together in one place for you:)
Part one of the theory is that the dog simply feels SO much better once they've been washed. Not only are they clean, they also had to sit still like a good boy/girl for SO LONG while they got cleaned and now they've been set free again!
The reason why they often roll around or drag their heads on the ground (my dog does this - we call it the "lawnmower") could be two reasons. One, they're wet and they want to get dry. Shaking removes a huge amount of the water, but not all of it - Especially in their ears. It probably feels weird and they're trying to get it the heck out! The other reason is that they likely don't like smelling like "not a dog" (with all the shampoo). Dogs rely on their sense of smell WAY more than we do. And all that shampoo is probably very distracting! Rolling around may likely be them trying to get their smell back to neutral.
And of course, if you associate games or fun activities with post-bathtime (my dogs LOVE being dried off with a towel), that likely makes them really excited too!:D
EDIT: Sources: _URL_0_
_URL_1_
I can find more if these aren't good enough for the people posting snark rather than real answers. | d8b45eed-9a52-45d4-8fdb-5fbf2d6d90fa |
1jhugs | What was the warsaw uprising | Warsaw was under Nazi rule. People didn't like that, especially the Jews living in the ghetto. People were purposely starved, killed in the streets. The Polish Underground State was formed - a resistance paramilitary which was made of several groups that wanted to liberate Poland (and save Jews).
Some folks with radios learned that the Red Army was coming. And the Reds hate the Nazis. And the Polish Resistance thought "Hey! If we fight the Nazis from within - and the Reds help out - we'll totally fuck the Nazi shit up!"
The Resistance started fighting - but the Red Army never came to help them. Those dudes camped outside the city. The Poles fought the Nazis for two months, much of the city was in ashes, and Churchill was all like "HEY STALIN, COME HELP OUR POLISH ALLIES!" and Stalin was kinda like, "I don't want to risk my dudes quite yet.."
That's the Warsaw Uprising. | c0a9c8aa-c2e8-4e5b-b875-018bf1e0ba92 |
2citow | How did the Romans express numbers in speech and/or calculation? | This is a really good question, you should probably chuck it over onto /r/AskHistorians, they'd be more likely to have an actual, factual answer.
EDIT: Someone has already asked it over there, the best answer last year came from /u/rosemary85 and goes as follows:
> No. The Latin words for numbers are fairly similar to those in modern Romance languages (unus, duo, tres, quattuor, quinque, sex, septem, octo, novem, decem, etc).
The Latin for 94 is quattuor et nonaginta, literally "four and ninety", or alternatively nonaginta et quattuor.
The exceptions are that the Latin for 18 and 19 are duodeviginti and undeviginti, literally "twenty minus two" and "twenty minus one". But as you can see, this has nothing at all to do with how the numerals were written.
I should perhaps note that the Romans very often wrote IIII and VIIII rather than IV and IX for "four" and "nine", XXXX rather than XL for "forty", etc. I don't have statistics at my fingertips, but I believe the IIII/XXXX forms were actually more common than the IV/XL forms that are preferred nowadays.
[See here for the rest of the comments.](_URL_0_) | dbc22cf5-374d-40b2-b2d1-6b55c0b85b85 |
26uc9v | What's the difference between Genetic Drift and Natural Selection? | Both of these concepts deal with traits within a population changing over time. With natural selection, one trait is more advantageous, so organisms with that trait survive and reproduce more effectively, resulting in more organisms with that trait. Genetic drift is when a trait becomes more common within a population due to luck.
For example, pretend we have a group of humans and some of them possess a genetic code that gives them green hair. If green hair is considered attractive, then those with the trait will be able to mate more and have more children. This is a benefit resulting from the trait being preferred. This means that nature selects positively for this trait and it is supported by natural selection.
On the other hand, let's again pretend that there's a trait for green hair but nobody finds it particularly attractive or unattractive. Logically, there's no reason why it should become particularly popular or unpopular. However, one day, a bunch of brown-haired people gather for a meeting in a building that catches on fire and they all die, while the green-haired people outside are unharmed. This event makes green hair more prominent within the population but it wasn't a direct result of any properties related to green hair. Since this was green hair becoming more common as a result of random events, this would be considered an example of genetic drift.
TL;DR: Natural selection means the trait itself is beneficial, making it more popular. Genetic drift is when a trait just happens to become more popular, even though there's nothing advantageous about the trait. | c33415d5-d795-48a2-8272-4b1e30fd1447 |
1howcd | Why do professional athletes have a significantly lower pulse than the average person ? | Because they have increased stroke volume. Their hearts are strengthened so that they are able to move more blood with each pump, so their hearts don't need to pump as many times. | 8fe0ea60-8ec9-430f-b9a0-d11a9175bffe |
36j482 | Pirate Bay Megathread | Pirate Bay's existence is NOT the result of a want for piracy. This is the misconception that has the industry execs spending HUGE amounts of time and money trying to control the symptom of a much larger issue.
People, like water, follow the path of least resistance. If the resistance becomes too much, we make a new path. Napster, Limewire, Bearshare, were all birthed as an affront to the system that made you spend $22.99 on a CD that had two songs on it you wanted to hear. Want to hear good indie bands? Tough shit. You get to chug the corporate swill and be happy to pay for it. Filesharing allowed people to get select songs from select albums quickly and conveniently. No more slogging through Best Buy.
"But Lobsterbib, surely the attraction to pirated music was driven by how free it was?" Nope. iTunes is proof that cost of music isn't the deciding factor in piracy. Convenience is king. People will pay for anything so long as they can get it instantly. Ticketmaster thrives on this fact alone. We'd pay the Devil himself if it meant we could get Emma Watson delivered.
If the industry could spend the same effort on combining their IPs into a singular venue that peeps could pay for and receive instantly, Piratebay would see its traffic PLUMMET. Wanna see crime drop? Legalize and regulate drugs. Want to see piracy drop? Make it easier to get content for fuck sake.
The other night I wanted to show my GF The Neverending Story. Turns out, no one is streaming it. All the video stores have closed so I'd have to drive all the way to Wal-Hitler to buy a $9.99 DVD in 4:3 ratio. Great way to spend an evening, amirite? I would PAY to see the movie if it were there! Get off your asses and let me give you my money!
So, until the elephant in the room is addressed, don't be surprised that it's pirating every episode of 30 Rock while you try to smash its wireless router. | 03964013-e4c6-4bf2-bc30-6c0cf35b192b |
460pvq | How, with the proliferation of free porn websites like youporn, does any porn production make money? | You like pink crayons a lot. There is this place where you can get free pink crayons, but you have to deal with ads and possibly malware. Also the pink crayons are low quality and the place may not have the specific type or model of pink crayon you are looking for. Now there is this other place where if you pay a bit you get the newest, best pink crayons that you choose as soon as they come out without ever dealing with ads or any other hassle. To some its worth paying for, for others the free place works. | a738cf87-4caa-4164-b7d2-beab58dde1b6 |
20evkj | How do landlords make money | so essentially making money from letting requires a large amount of time and/or starting capital? | ec0b8ae9-cf00-4c1b-8c45-d25fa8c7076c |
tndup | Why do DVDs in widescreen format play with black bars on top and bottom on my widescreen TV | Just because it's "widescreen" doesn't mean that it's the same exact aspect ratio as your TV. A movie with black bars on the top and bottom was filmed in an aspect ration that's even wider than your widescreen TV.
Look [here](_URL_1_). Most widescreen TV's are 16:9 (the third from the bottom on that page), and many movies are filmed in 2.39:1 (the one on the very bottom). Clearly, you cannot shrink the bottom one to fit on a 16:9 screen without having bars at the top and bottom with no picture. Well, you can if you can tolerate a distorted, squished picture. Another option is to use [Pan and Scan](_URL_0_), which gets rid of the black bars at the expense of cutting off the sides of the picture. | 55234316-4329-4939-bb48-5d840eecad2f |
7yy4pa | How do spammers spoof a cell phone number to make scam calls? | When you make an outbound call, the calling system gives the phone system the caller ID information. The reason this can be (legitimately) different from the actual call is for example a business that has both direct lines to each extension and a main line. An employee calling out would show up with the main line as their caller ID so that if the person calls back they get the main number (this way you’re not giving out the direct number unless you needed to).
The spammers take advantage of this system to spoof a number in the caller ID.
The phone company could counter this by comparing the caller ID info with a number you legitimately own, but they get a lot of money for all these spam calls and they’re not incentivized enough to change how they do things. | cc4ed988-0498-4be0-bb89-4196177b582f |
5xokvr | How have wolves impacted Yellowstone? | This is just one example.
More grazing animals means less vegetation for other animals to use as a home or shelter from prey.
They also took vegetation away from the river banks causing more erosion. (The roots held the soil in place)
The reintroduction of wolves stopped that and kept the grazing animal population in check, allowing the vegetation to grow back. | d4c38b5a-3816-4fef-8afa-cd100c6ec80a |
xr9iz | How do we move our body? | Planning and decision making for motor movement happens in the [premotor cortex](_URL_0_). To see where it is, find a spot on the top of your head that's about three inches back from your hairline. This is the section in your brain that makes the decisions about lifting limbs and looking at the ceiling. It takes in information from many parts of the brain including the senses, the emotional centers, and long term planning structures before making a decision. When it decides, it sends a command to the [Motor Cortex](_URL_1_) which is just a bit closer to the back of the head. The Motor Cortex is a doer. It takes the big decision made by the Pre-Motor Cortex and figures out how to implement it. "Move your leg!" says the PMC, and the MC calculates what muscles in what order need to be fired. If it's a movement that's been done to the point of being automatic (like walking or tying shoelaces) then the MC relies some on the Cerebellum to coordinate, as the Cerebellum stores all those highly practiced movements. | 391f34d9-79d2-4ba0-bcef-76c0fbce0459 |
1x0nfz | What is the difference between a CEO and the President of a company? | "President" is a term that is often based on the law of the place where the company is created. For example in the United States, most states require that a corporation have a person with the title President. That title carries with it some legal obligations that tie the individual to the actions of the company.
Most jurisdictions don't define or require anyone to hold the title "Chief Executive Officer".
Depending on the size of the entity, the President and the CEO may be the same person. Large entities may be comprised of several smaller companies, each with a legally required "President", who may report to the CEO at the top of the organizational structure.
Some companies may separate the two titles for internal organizational reasons, for historical reasons, or because someone thinks it's clever.
It is rare for a company to have a CEO who reports to a President. CEO has become the de facto title for "the highest level of the executive ladder", but that's arbitrary and fashion could change. | 6392cff8-1c58-46c5-8b00-8b2aa8280399 |
3783a1 | Why does smoking cause some people to lose limbs/develop cancer while there are lifelong smokers who never have these problems? | The short answer is that at the chemical level biology is very complicated. We tend to think of all sickness and injury the same way we think of, say, a bullet wound---a single, distinct harm that directly interferes with how something in the body works in a simple way.
But that's not how all harms work. Nicotine and other carcinogens can cause damage in many ways and at many levels. They can harm cells, different parts of DNA, and different things in different parts of the body. And these harms might not happen every time, or from every puff, depending on random chance.
And even when they do cause harm, it might not be enough. Maybe person A has a stronger immune system then person B. Or maybe person B happens to be genetically more vulnerable to cancer than person A. Or maybe person A ends up getting cancer in a cell that happens to get killed the next day by a bacteria, while person B gets it in a cell that survives long enough to grow.
There are so many variables between exposure to the toxic substance and the expression of some linked disease that even when the negative health effects are clear---as with smoking---it is almost never going to be the case that everyone will get the same injuries, or even any injury at all. | 204c1250-1ff8-4109-85ee-2948b8047fe8 |
38vqhs | Why is it, that when I get really tired, everything is so much funnier? | The phenomenon of being more easily amused falls under Emotional Lability which means emotional changeability or instability. You're probably more likely to cry too. In extreme cases, this is a medical condition, see _URL_0_ but in regular life, it's just that the parts of your brain which keep you on an even keel aren't working quite so well. | 7fa5687a-ec1d-42a9-999d-12c10baf138d |
2r9rpr | Why you need to be grounded to get an electric shock? | Electric currents aren't like Austin from middle school, they don't come out, wander around, bug people, and then go back home.
Electricity flows from negatively charged objects, to positively charged objects, until the system is neutral. That's all there is to it. If electricity flows from one location, that means that location has a negative charge, and the electricity *doesn't want to go back*. It wants to find the most positively charged location, and make it balanced.
If the most positively charged location available is the ground, then it will happily go through you to the ground. If it is an anode, then it will do that too (which is why it's dangerous to work on electronics with two hands). | 1e7fec68-c96b-45db-9053-e47e712461ee |
67xqzm | How do people get infected with plaque? | Plaque isn't just one bactera it is what is known as a biofilm. Layers and layers of diferent bactera and their extracellular matrixs. Pretty much any bactera can eventually form biofilms. Everyone has bactera on and in their bodies called their natural flora. Your natural flora bactera grow into the plaque on your teeth. | e628e597-0490-4848-9948-5ae875cfce92 |
7lgolq | Why is it that a hard drive disc can have a capacity of 5TB+ but DVDs can only have a maximum of 9GB? | In addition to what's already been said about the actual technological differences, one major difference is working conditions.
Hard Disks are produced and sealed in clean factories to ensure there is no contamination. They are encased in thick unbend-able metal. From the day you start using it, you can't bend it, get it dirty, scratch it, or really abuse it in any way. The parts inside that rigid case are precisely machined to fit together and be aligned perfectly, and because you can't stick your fingers in there, they stay that way. Precision engineering.
Meanwhile DVDs and other similar disks are made from cheap soft easily scratched, easily bent plastic. In use they get coated with your filthy greasy fingerprints. They'll get scratched when you handle them, when your kids put them in the player they'll get jam and cat hair over them. You bend and distort them each time you remove them from the case, and you can put them in a huge variety of players of varying quality.
So while the hard disk can afford to store one bit of data in an incredibly tiny spot on the disk because it knows it will have the precision to address it exactly, safe from damage, dirt, and distortion, the DVD has to keep its bits of data in larger lumps so it can still be seen through your filthy fingerprints and coffee stains on your bent and scratched disk. It also keeps some parts of the disk to store checksum information (a bit like backups) to make up for those bits it still can't read. | 87e95905-f7fe-40cd-bc4e-61900bcd1ee9 |
50cjak | How much racism/discrimination do Europeans who live in India or Africa face? | Maybe it's not racism or discrimination in the traditional sense, but I've heard anecdotally that whites in Sub-Saharan Africa are more likely to be targeted by robbers because they stand out it's presumed that they have money. | 690e1e36-2cb2-4832-bb32-cff0c3ca022a |
3o6lfy | Why does a company like Boeing need to make a commercial? It's not like anyone watching is going to buy one. | Companies that have to choose between Airbus or Boeing still consist of people (who can be manipulated through commercials), and they can sadly often do so with bias even though they're supposed to run the numbers and make an informed decision. | e58bedae-2c71-49b2-bd2e-6ff3d6de110f |
1lz78h | How do American football have bruised lungs without also having broken ribs? Isn't that the point of ribs? | This is actually one of the major issues with American football. The padding protects from the blunt hit and spreads out the impact so you aren't taking a lot of force to a particular place on your body, but your body is still being shoved really hard as a whole. This means the force is spread out and absorbed a bit so your skeleton isn't taking such a direct impact, but since a body at rest tends to stay at rest, when you get hit, your organs like to stay where they are as your skeleton is forced to move and they bang around inside their cage. | 609e02e4-adce-42e8-9e30-96d07c38c0f5 |
30uvdy | What are dentists actually doing when they scrape at your teeth with those metal picks? | I think my dentist was counting money while my hygienist was scraping my teeth. | 9d18f81e-ef1f-49df-8649-101367bdcf03 |
lpywz | When did we stop having to type in 'www.'? Why did we have to to begin with? | It's because servers where traditionally named according to the services they provide. So a world wide web server had www., a file transfer protocol server had ftp., et caetera. We stopped having to type it because nowadays, the www._URL_0_ and _URL_0_ URLs both refer to the same server (URL is like a set of coordinates on a map that is given to your web browser to go and find the web site). Some sites don't, and so typing either form might yield different results.
Most browsers also add the www. in automatically, to stop any problems that might occur. | 9dafc444-841c-4e4a-8c9f-a7d7c2f0c04d |
64o7nd | What is the difference between real and imaginary numbers? | "Imaginary" is a bad word for them because they definitely exist, they're just part of the complex plane.
Imagine the number line, which contains all "real" numbers going off left and right into infinity. Left is negative, right is positive. Take a step to the right and you're at 1, a step to the left and you're at -1. Now imagine you take a step *forward* instead of left or right. Or you take a step backwards. You're going *somewhere*, you're going to a number - a number that definitely "exists" but it's not on this line that contains all "real" numbers. So when you take one step forward, it's not in the 1 direction, it's in the i direction. A step backwards is in the -i direction. Two steps is 2i, then 3i, etc. You have another number line that stretches forward and backward to infinity, which is the "imaginary" number line. When you put them together, you get the complex plane: that is, if you take three steps to the right and four steps forward, your position can't be described just by the real or imaginary number line, it's at 3+4i.
You can do this again with the "up/down" direction and create another number line that isn't real *or* imaginary numbers, that goes into three dimensions. Those are *quaternions* - units of numbers that are further into complex dimentions. The new line is marked with j, then k...and you can just keep going into more and more dimensions.
[Relevant Numberphile](_URL_0_)
EDIT: A word, and I'm bad at math. | 193e5e8f-eea4-4926-a291-5c316f81dec9 |