question
stringlengths 19
300
| answer
stringlengths 31
1.02k
| negative_1
stringlengths 31
1.02k
|
|---|---|---|
Left Wing vs. Right Wing | **Right wingers**: "Federal Government should **not** interfere with the private sector. Morals and values are extremely important. Don't fix what isn't broken." **Left wingers**: "Federal Government is a valuable tool we **should** use to help the nation. Social liberties & civil rights are extremely important. We must strive to constantly advance our country." Of course the deeper you delve the more complicated it gets. But that's the basics, and why liberals and conservatives are almost always on opposing sides. | As I understand it, when you have two opposite political sides, the more extreme they get, the more closely they resemble each other. For example, comparing Fascism (Dictator controls everything) to Communism (Everyone is equal, the community owns everything). These are usually considered complete opposites, but in truth, Hitler's fascist Germany and Stalin's communist Soviet Union were both cruel dictatorships and gave the government absolute control over the people. People recently have been comparing the alt-right & white supremacist groups to their opposite group, Antifa (anti-fascist). Antifa oppose fascism, but they will ironically violently fight views that oppose their own, which many people are claiming is silencing free speech and is just fascism in the other way. |
Is spacetime literally curved? Or is that a metaphor/model we use to describe the gravitational concepts that we don't yet understand? | Physicists construct mathematical models, and use these models to generate measurable predictions of experiments. I guess if you want to get really philosophical you could question if a correct model and the real world are the "same thing". But I'm not sure if that's what you're asking. (For the record, in my opinion they are not). In general relativity, space-time is modeled as a 4D mathematical space, called a manifold. Depending on what kinds of matter or energy live on the manifold, the manifold can be curved. This curvature ends up showing up as "ficticious forces" when you write down the motion of a particle that experiences no other forces (like electromagnetic, etc). So within the mathematical context of this model, yes, spacetime is "literally curved". This [entry](_URL_0_) on curvature is a bit technical, but there is an informal description also. | As Einstein showed us with general relativity, gravity is curved geometry. The presence of matter/energy results curves spacetime. Particles (both massive, and then massless) then follow the shortest paths in this curved spacetime, which results in what we think of as gravity. |
The difference between Popcorn, Potato, Reheat, Defrost, etc. on a microwave | Timing and power. Potato might be low power, defrost is med power that cycles on and off to not change the texture as bad. Popcorn is a preset amount of time that they came up with. Reheat is high with some sitting time to let the heat mix thoroughly. You set the weight so you don't have to reference charts to know his long it will take. | Microwave oven works by rotating water molecules faster and thus generating heat and cooking the raw food. If you just boil a potato in water the cooking would take place from outside to inside. But in microwave the cooking would happen quite homogeneously due to the homogeneous presence of water molecules inside the potato. |
In economic terms, what does it mean for something to be elastic or inelastic? | Elastic means that it is sensitive to price changes. Inelastic means it is not sensitive to price changes. | This means: how much will people switch from one product to another, in response to changes in their prices. Very elastic means they'll jump ship over a very small change in price. |
Why we don't constantly feel "growing pains" at a young age? | Research has been coming out suggesting that vitamin d is the cause of growing pains in children. [This study](_URL_0_) found that 86% of the children they studied had vitamin d deficiency, and after giving them supplements there was a drastic reduction of pain. What is implied then is that during this period of childhood the body uses much more vitamin d than in others periods. This was also something I learned in my nutrition class in college. It used to be more common in the northern states, along with rickets in what is called the "rickets belt". Southern states are starting to see a rise in these issues as well since kids are staying indoors for longer periods of time compared to 50 years ago | Infants and children need bonding and attachment. When they get hurt, they aren’t sure what to do and rely on the adults around them for comfort and care. We as adults teach children that it’s ok to fall and get back up from it to keep going. It’s what we were taught as children and now as adults it’s easier to stub our toe or run into something and continue on without crying. Pain tolerances grow during childhood because we are taught to get up and brush it off. These are with acute injuries (falling and getting a scraped knee, stubbing toes, or being clumsy). During a more serious injury, our adrenaline is pumping through the body as a fight or flight response (automatic) and the actual pain from the injury may not have registered yet. |
What did Rockefeller mean by 'Competition is Sin'? | [It appears he didn't say it](_URL_0_). And this would be the sort of propaganda put in his mouth like "let them eat cake" attributed to Marie Antoinette. The attribution is an attempt to point out Rockefeller's habit of colluding with others to dominate business. Which he did. There's really no need for the propaganda, but it started up in the 1970's. | My time to shine. The term "Rockefeller Republican" comes from Nelson Rockefeller, New York Governor (and later Vice President) in the 70's. The term is largely archaic. Rockefeller republicans were moderate republicans who were fiscally conservative but socially liberal. (I'm speaking in very broad terms here, I know.) They supported equal rights, a well-regulated economy, labor unions (to a degree), and other such legislation/institutions. This set them apart from their more conservative counterparts, and would certainly set them apart from libertarians and tea partiers today. RINO's (Republicans in Name Only) is something of a pejorative term used to describe Rockefeller-type republicans. Edit: Don't mind me. Just correcting some of my asinine phrasing. |
Is there any connection between the word Abraham and the Vedic word Bramhaa? | Assuming you mean Brahma: etymologically speaking, no. The Vedic (Sanskrit) word is Indo-European, while the Hebrew word is Afro-Asiatic. Rule of thumb in these kinds of situations, unless you can make a really strong case for derivation, is that similar words in different language families are coincidental. | This does need some clarification. Much of Genesis was likely written during the second temple period. There isn't any way to know the history of the oral tradition before that, if that's what you are asking. As a side note, Abraham didn't really *lead* the "Jews" (a term which didn't exist for several more centuries - they were Hebrews); that was done more by Moses, then Joshua, then a longish string of familiar names. Abraham served as a model of obedience to the Hebrew god and as an explanation for some of the history of the Hebrew people. History in this sense is not history as you or I would define the word; it is not a literal, factual account. It would be good if you could restate the question or break it up a bit to make it clearer what you are asking. |
It's there any account on how Yuri Gagarin was effected by the death of Vladimir Komarov? | Just FYI, You'll want to look into _Starman_ by by Jamie Doran and Piers Bizony. I was pointed to it by this [article on NPR](_URL_0_). (I haven't read it yet so I can't comment further) The two were incredible friends; Vladimir knew the ship was doomed, but went through with it because if he didn't, his friend Yuri would have to go. Knowing a friend did that for you, would have a pretty significant hit on anyone. | Some Russians hate him to death, some respect him (I'm not joking). Remember that he took power when USSR was devastated agrarian country after bloody civil war and he left it as world superpowerer with nuclear reactors in beginning of economically fruitful 50's, so even political repressions don't scare his fans. Well, some people like strong hand, and we have idiom 'При Сталине такой хуйни не было' which could be translated as 'There was no such B.S. during Stalin's rule'. He used to rate political problems far more important than everyday practical problems. |
what's the point of runway shows? | As far as I can tell runways are to display the concept and the art behind it, elements of the runway show get whittled down into everyday wearable stuff. | It's mostly to ensure that the show stays at a fluid pace with no awkward breaks or bsing in the dialogue. Doing it live is brave, but also very risky, and doing it show after show would mean that there would be no guarantee in quality. |
Why did/does the US hate communism so much? | Every real world "Communist" government has been a brutal authoritarian regime that uses Communism as a dogmatic justification for its villainy. Even if you speculate about an idealized Communist utopia, you're still structured your society around the notion that people are merely fungible elements of a certain socio-economic class rather than individuals with their own needs and wants. Given the strong streak of individualism in classical American character, such a notion doesn't tend to sit well. | The easy answer is that they paid lip service to some of the ideals of communism but had no intention of creating anything like a "worker's paradise". The fact that from their inception every "communist" country has been under threat, from within and without, by forces dedicated to restoring the old order also led to more domestic oppression than we might have seen if the capitalist West had accepted the communist states and traded with them freely. Another reason is that all the communist countries were run by brutal dictatorships *before* the revolution so there was no tradition of democratic decision-making and truly representative government. |
Is the heat that radiates from humans (and other living things) enough to effect the temperature of the Earth on a global scale? | A person radiates something like a 100 watts, so 7 billion people are putting out 700 billion watts. The earth receives something like 200 petawatts from the sun. So the heat from humans amounts to something like 0.00035% of the heat coming in from the sun (which is the primary driver of Earth's temperature). Even adding in all other living things I doubt it gets close to 0.1%. | Yep, heat radiates away from the Earth constantly, mostly in the form of infrared light. Approximately as much heat goes out as comes in, which is why the Earth's climate is stable over long periods of time. This is actually what the danger of climate change is about: we're changing our atmosphere so that less heat radiates away. That will increase the overall temperature of the planet, which will cause a number of changes in our climate. |
Why doesn't the windchill affect my thermometer? | Wind chill is a made up number; it has nothing to do with the actual temperature. It indicates (sort of) what it would feel like to stand in a room with non-moving air at a given temperature. So if it's 30 out and there's a 20 knot wind blowing, your body would lose heat as though it was 20 out and there was no wind blowing. So, why does it feel colder to a human but not to a thermometer? Fairly simple - a thermometer becomes the temperature around it. When the wind blows, the thermometer doesn't lose any more heat - in our example above, it's already at 30 degrees just like the air around it and moving the air around doesn't change the temperature. However, as a human, you're trying to keep your temperature around 98 degrees; this is quite a bit warmer than the 30 degree air around you. You lose heat at a certain rate when the temp is 30. If the wind blows on you, you lose heat even faster - as though the temperature were lower. | They can't. A thermometers can detect the temperature, but human can't do that. What human can do is feel the rate of energy transfer between your skin and your environment. That's why water feel a lot colder than the same temperature in the air. Since water absorb energy faster than air, the water will absorb heat from your body faster, which ''feel'' colder to us. Something similar happen with wind. Without wind, your body heat a layer of air around your body, which slow down the lost of heat. But wind will blow out that layer of air, making sure you are constantly in contact with cold air so you will lose heat faster. There is several factors that will affect how fast you lose heat. |
What actually happens when your finger gets "jammed" and why does it hurt so much? | Your finger takes enough force that this force directly translates as pressure to the bones. The bones bump at the joints, causing a bone bruise at the joint. The injury can be accompanied by strain on tendons/fibers depending on how the injury occurred. Pain is caused by the chemical response to the injury, and the nerve endings available to receive the signals. In your fingers, there are a lot of nerve endings, presumably (from an evolutionary standpoint) to allow for sensitivity and control. We use our hands for so much that it is good to be able to tell a lot about our environment from the hands. The greater number of nerve endings means a more intense response (pain). | It shares a tendon with the middle finger which cases it to lack the full scope of movement a regular finger would have. |
Is it possible that a good portion of the cancer today was caused by all the radioactive products created for the public back in the 50's? | I'm not an expert, so hopefully one of the more qualified members of /r/askscience will step in. That said, many more things are known to cause cancer than radioactivity. Smoking, for example, is an easy one, and it's something that much of the rest of the world does. The WHO says: > About 30% of cancer deaths are due to the five leading behavioral and dietary risks: high body mass index, low fruit and vegetable intake, lack of physical activity, tobacco use, alcohol use. [WHO site](_URL_1_) | It was, it just wasn't always "diagnosed" properly or even aware of it happening. Today it's less that we get cancer more, but that we recognize it more. |
Inductive & Deductive reasoning | Inductive: The sun has come up every morning that I can remember, so it will probably do the same tomorrow morning. Deductive: 1) The sun comes up every morning 2) It is morning. Therefore: The sun will come up. Summary: With inductive reasoning you get an answer to a problem based on what answers you got to similar/same problems before. It's quick and useful, but not 100% certain. With deductive reasoning you work from reasons that, if they are true, mean that the answer MUST also be true. | Deductive reasoning: If X is true, then Y is true. I know that X is true, and therefore I know that Y is true. Inductive reasoning: In every specific case I've seen, Y has been true, so I think it's always true. |
Why if let outside does my cat stay on the property whereas my dog would runaway? | Because the cat owns the property. The dog is just a guest. | Safety. Many animals instinctively like being in confined spaces because it usually means you're hidden, nothing can come up behind you, and nothing bigger than you can enter your little cave/nest/nook/home. Your cat probably isn't consciously thinking these things -- it's just developed an innate attraction to such spaces over the years because evolution fosters cautious/defensive instincts like that. |
Why isn't junk food good for bodybuilding? | Depends on your philosophy. A lot of bodybuilders will do what's called "dirty bulking" which usually entails getting a lot of calories from junk food. Just because a lot of these guys are consuming 4000+ calories per day, and you can only eat so much chicken, rice, and broccoli. And some subscribe to an idea called IIFYM (If it fits your macros). Basically, that getting your carbs from brown rice or poptarts isn't relevant. However, junk foods don't have a lot of vitamins, minerals, or fiber, which are necessary for a well-functioning body. Also, many junk foods with high sugar content can cause high levels of insulin, a hormone that can promote fat retention. | Junk food is generally very calorie-dense. Millions of years of evolution have made animals seek out high-calorie food sources. |
Why does sound always propagate at the same speed though a given medium? | In non-dispersive media, sound travels at the same speed no matter (or rather, differences are negligible). This assumes constant temperature, pressure, density, and composition of the medium. In dispersive media that's not what happens. The speed of sound will vary with frequency. An example of that is water and solids. An interesting question though is not how fast does a wave travel, but when does the energy from a wave arrive? It turns out that energy at different frequencies can be delayed by acoustic effects. We exploit that for acoustic engineering, like in the design of loudspeakers. | Sound waves travel faster through solids than gasses, but it takes a lot of energy for them to actually move between mediums, reducing the amplitude (volume) of the sound wave. |
Is there any credibility to the claim that recent NASA data shows a weakness in climate models? | _URL_0_ < - Here is an article discussing this particular paper written by climate science experts. They go through and show why the paper is incorrect. _URL_1_ < - This article deals with several past models the author (Roy Spencer) has released. Basically the issue with Spencer is that he is convinced CO2 has no effect on climate and writes models that work equally well for low and high CO2 sensitivity and forces them to give him a low value. Basically in his models other parameters can adjust if you change the CO2 sensitivity so you can get the same fit. However, the problem here is that the values he ends up with are not physical because he doesn't restrict the parameters to only physically possible things. He does other silly things like saying the ocean has no temperature variation with depth in his first iteration. In short he has an answer he wants his research to show (no global warming/CO2 does nothing) and he tweaks his overly simplified models until they show that. | Reasonably accurate - but I would not call the CO2 direct warming as "minimal". I am also not a big fan of the suggestions behind this wording : > What we have seen since 1998 is a plateau in global temperatures. The thing is that 90% of the warming is going into the oceans, and since 1998 the warming was absolutely certainly not on a "plateau', so you should also take a look at: _URL_1_ _URL_2_ _URL_0_ I also believe that deniers that were clinging on the "feedback is negative or neutral" story will have increasingly harder times with their lies starting as early as 2013, which will kill most of the records set in 2012 - and they will most likely switch to other lies like "it will not be that bad" and "we can not do anything about it since it will hurt the economy". |
Why is blue cheese (mold) different than black mold (in my house)? Other than if it's edible or not? | For the same reason that ball pythons and rattlesnakes are different. Those molds are different species, and one of them as part of its metabolism makes delicious cheese, and the other makes poison that will kill your lungs. | Different species of mold have make different byproducts as they grow, and not all of them are harmful. Through experience we know some that are safe, like those used in making cheese. (Yeast is also a fungus, but not a mold, and is used for baking and brewing.) When food around the house gets moldy from whatever spores were in the air, it's a bad bet: there's a big risk that whatever mold it is either is generally poisonous or might produce something you're allergic to. This why cleanliness is actually very important when working with mold. Get the wrong kind of fungus in your product and it will ruin the whole batch. |
Have there ever been any truly female-dominated societies? | I'll leave it to someone more knowledgable than me to share the details, but the Celts are one of the best examples of matriarchal society. During Hadrian's conquest, it was remarked that Celtic women were fiercer than their men, and they would commonly take part, or even command, in battle. You may recognize Boudicca from Civilization; the Celts were such fierce warriors that the Romans gave up their winning streak in England and simply built a bigass wall at the northern reach of the empire, which still stands today as Hadrian's wall. Edit: Just wanted to thank the awesome mods for not removing my source-less post, forgot to mention I spent time in Heddon-on-the-wall and took a few classes on the time period. | Okay team: we have established there were female rulers outside of England. Now it's time to build on that and explain *how* females were viewed in those leadership positions; how did that individual move around the political landscape while performing femininity (or as the case might be, masculinity?) |
Why Are The Winners of Running Competitions Like Marathons Almost Always From Africa? | The "Kenyans" train very hard. They also train at a very high altitude. When they come down to sea level and run with us puny Americans they have an easier time because of how much oxygen they need to accomplish the same thing. Kind of like how sherpas can jog all over Mt Everest. | West Africans have a more curved femur than whites or Asians. Most black Americans are of west African descent. This is why they jump higher and are faster sprinters. East Africans are the exact opposite with straight femurs, Obama for example. This is why they dominate in distance running. |
How close would we have to be before Andromeda would be visible in the night sky? | Andromeda [is naked-eye visible](_URL_0_), though you'll have to get away from city lights. | Im a bit confused what you're asking exactly. Do you mean what the sky will literally look like to a person looking up at it from Earth? Ignoring for a moment that the Earth won't exist in 150 billion years, and the fact that most of the stars will haved died and been replaced.... Nothing will really change due to the shift of galaxies beyond the horizon. Nearly everything you see in the night sky is within a few hundred light years of the Earth. Most of the milky way isn't even visible to the naked eye. There are only a handful of other galaxies that are even visible to the naked eye, with Andromeda being the most obvious, however it's only visible in extremely dark skies, and looks a bit like a very dim smudge. Nothing outside our local cluster is even remotely close to being visible to the naked eye. |
How can FOX News spend years lying about planned parenthood and not be held liable when a viewer shoots up a clinic? | Because we don't hold people liable for things like that. There's simply no precedent.Fox News never told him to do that action, it didn't even suggest a violent response. To hold them liable would be quite a stretch. | Right wing politicians don't like planned parenthood because it provides abortion services (on top of other services like birth control, breast screenings, etc). There was a video that was edited to make it look like PP was doing something illegal. The politicians ran with it because in their minds, the ends justify the means. "What they did" was attempt to negotiate profit margins for the selling of fetal tissue (this didn't actually happen, it was just made to look as if they did). Planned Parenthood and other clinics are allowed to receive money from tissue donations. That isn't illegal. |
What were travel times like in ancient mesopotamia ? | I made a brief post earlier this year which might have some info you're after, seen [here](_URL_0_). I strongly recommend reading the paper linked in that post, *The Road To Emar*. It'll give you the details of what we know about Mesopotamian travel times and the texts from which we know it. If the paywall is a problem, I can summarize later. For now, I'll note that you typically wouldn't have had a mount to carry you in your travels. Mules and onagers were used as beasts of burden, and horses were used to pull chariots, but no animals were generally fit to be ridden until the adoption of cavalry by the Neo-Assyrian empire, around the beginning of the 1st millennium BCE. So, your rate of travel would generally only exceed walking speed with the help of a boat, which were (and still remain) a common and important method of transportation. Boats would be shallow and small, and often merely consist of a woven-reed raft, especially in the marsh-like southern areas where serviceable wood was a scarcity. | From what I understand, travel was fairly limited during that time. Most people preferred to stay in once place and at most they would go to market to trade for goods. One thing that you might want to understand was that the people from the village just over the hill would be just as foreign as the people who came from across the ocean. Heck there was a pretty good chance that you would have two villages on the other side of a valley and each would speak their own unique dialect. Of course this is all from the perspective of the peasantry I can't really speak for the traders themselves. I hope that answers at least part of your question. |
Sound in the interstellar medium | The mean free path of particles in space likely far exceeds the amplitude of any acoustic oscillations; meaning that sound does not propagate. | The interstellar medium is mostly plasma, and it generally orbits around the Galactic center in more or less the same way that stars do. It *is* being pulled by gravity. Individual stars' gravity is pretty weak outside of their immediate system, and they generally have stellar winds that push gas away as well. |
Making 'Bullet Hell' Games | Once your familiar with the mechanics of the game you developed yourself it isn't that hard. Most bullet hell games use enemies that follow and create simple or complicated patterns. The developer is the one creating the patterns so he can also make sure there's safe zones within the patterns. It's kind of a trial and error process, start creating patterns. Review them, adjust them, review them again. Don't forget that the developer is in control of his tools, many game engines can be slowed down for instance to view events in slow motion. [The super mario dev's created a level that plays itself. Ie. if you don't touch a single button, Mario will reach the end of the level unscathed](_URL_0_). They were able to do this because they're very familiar with all the individual components they're working with, after that it's just trial and error to set up a Rube Goldberg device like this. | Games and movies often dispense with reality for the sake of storytelling. Fire and smoke look cool, and in a move or a game looking cool is way more important than accurate physics in your portrayals of fantasy space gunfights. Pew pew! |
Is it possible that someone could have survived in the Titanicand died later at the bottom of the ocean? | No. The wreck of Titanic is about 3800m below the sea level, which means that the pressure is about 380 times the atmospheric pressure. (At that pressure, air shrinks to about 0.26% of the sea level volume.) Even if it there were big enough pockets of air to breathe, and a possibility to keep warm, people would die of nitrogen or oxygen poisoning. | I'm not the OP but one question I've been curious about is how many of the Titanic's passengers the Californian would have had the capacity to rescue. |
Were there any crime organizations in Medieval Europe? | The only one that comes to my mind (and that only cause of their connection to [Francois Villion](_URL_1_) ) are the Coquillards. A "gang" of criminals that were active in the north of France in the 15th century. In his ["Small Testament"](_URL_0_) he describes the break in the Collège de Navarre in Paris. And who helped him and so on. But I am pretty sure that there are people here who can shed more light on that. | Heya! I talked about the prevalence of medieval banditry and who the bandits were in [this earlier answer](_URL_0_). I hope this helps! |
The Earth has 7 billion humans. Humans produce c02. Could this be a reason why our c02 levels are so high? If no, why not? | Humans, on a biological level, produce a very very very tiny percentage the worldwide CO2 production even if other human sources of CO2 (such as fossil fuel usage) aren't counted. Fossil fuel usage is really the largest contributor. | well, it's not that increasing carbon dioxide levels will destroy all life. If it spikes too quickly, it may cause a mass extinction of sorts. But life will still persist, and evolve into something different. The threat is that we will turn the earth into an environment where we can't survive. It's a threat to humanity, not the earth. |
Could Stalin realistically have pushed the Allies out of western europe shortly after 1945? | I personally can't even begin to answer this question, but interestingly enough in June 1945 Churchill was wondering (almost) the same thing as you. He ordered the Joint Planning Staff to draw up a plan for what would happen if the British were forced to defend against a Soviet drive towards the Atlantic following a withdrawal of the American forces from the continent. The report concluded that if the United States focused on the Pacific theatre, Great Britain's odds "would become fanciful." Anyway, there's a little bit more on the [Operation Unthinkable Wikipedia article.](_URL_0_) It might be of some interest to you but I can't help any more than that I'm afraid. | Which plan of Churchill are you asking about? Both the planned [Operation Pike](_URL_1_) and [Operation Unthinkable](_URL_0_) would have involved offensive operations against the Soviet Union. There were also [Franco-British plans to intervene in the Winter War](_URL_2_) against the Soviet Union. |
How does LCD (Liquid Crystal Display) work? | Yes there are little crystal structures inside the displays. They are extremely small and spiraled like a staircase turning 90 degrees. Light is polarized before hitting the LCD screen.(Made to all go the same way) When you apply an electrical current passes through them it can block light from passing through. Each tiny pixel on the LCD screen has three smaller cells. One red, one blue, one green. When all three are on you get white light, by blocking the light of one, the other two make a new colors. The amount of the voltage applied controls the intensity of the colors giving us different shades. | Because it *is* liquidy. The screen uses something called a "liquid crystal", which is a layer of a special liquid sandwiched between two pieces of glass or plastic (or one piece of glass and one piece of plastic). This liquid is what forms the image, by changing how it interacts with polarized light depending on the electric field applied. |
Why can one judge's ruling set a precedent? Isn't that too much power in the hands of one man? | If one judge is making the decision, it's likely to be a trial court decision. Trial court rulings can be appealed, and appeals courts have more judges. At least in the US, trial court rulings also don't set binding precedents; other judges may be *persuaded* by the ruling, but they can ignore it if they are unconvinced (whereas an appeals court binds courts down the appeal chain, and they can't just ignore it). | In some cases, the judges don't have a choice. That's sort of the point of mandatory minimum laws, although I don't know what specific cases you're referring to. |
Why is it impossible to remember being born? | The human brain is incredibly complex and is not fully developed at gestational term. The skull is not mineralized and consists of several different bony plates to facilitate passage through the birth canal. At birth the human brain lacks the ability to form memories because that function is 1) not yet developed and 2) not necessary at that point in time. Humans basically survive off reflex activity during this time, and brain development manifests itself as measurable physical milestones at certain ages. Contrast this to something like a fawn, which can begin walking shortly after birth. The fawn has the time to develop its motor function to that point *in utero* and therefore can be born with that ability, overall the fawn's brain is much simpler than a humans and requires fewer neuronal networks to function at that level. That level of development is possible and the fawn can still pass through the birth canal. | If you can't recall something, then for some reason you can't connect the neurones that hold parts of that memory together, usually because other pathways are opening up and blocking it. But really we don't have a clear understanding of how memory works. |
Why is it that if I put up a fence around my yard with signs stating I have a dog in my yard that someone can jump the fence, trespass, get bit by my dog and I'll get sued? | Any can sue anyone for anything. That said, a fence and a sign help to limit your liability. If you have a normally friendly dog and someone jumps the fence and gets bit your liability is rather small. If you have a known vicious dog your liability is still quite large because you should have known a fence wasn't enough. | The "fence " is a wire that the people put around their property. There's a gadget on the dog's collar that gives the dog a mild shock when the dog crosses the wire on (or under) the ground. It is very imperfect and it's a crummy way to treat a dog, IMO. |
How does cryogenic sleep work? Does a person in cryogenic sleep age? | cryogenic sleep is science fiction, so you can write your own rules for it however best suits your plot. | The trouble with "cryosleep" is that we can't freeze a person fast enough. Unless a person is frozen VERY quickly, "ice" crystals form in their cells' cytoplasm, causing those cells to rupture immediately on thawing (obviously killing them, most of their cells are now dead). Theoretically, if we could freeze a person quickly enough, or after introducing some sort of chemical that prevents the crystallization, cryosleep would be possible. |
Why do we produce earwax and what benefit does/did it have? | Earwax is a lubricant, just like beeswax or tallow, and it helps to keep nasty things out of the ears. | Earwax is mostly keratin and long chain fatty acids. The oxygen that evolves from hydrogen peroxide breaks up these polymers, allowing the water to carry the liquefied ear was out of your ear more easily. |
Why is volume measured in positive values (0dB for quiet, 100dB for loud) but on a sound mixing desk it goes from -infinity dB (quiet) to 0dB (loud)? | I only learned this recently myself. The way to think of it is that when using the sound desk you are restricting the flow of sound passing through. So if you set it to 0db you are allowing all of the volume provided by the amplifiers to pass through, set it to -10db and you are cutting off the top 10db produced by the amplifiers. | 0dB isn't 0 sound - it means that the sound amplitude is at the bottom of average human detection. The dB scale is logarithmic - the numbers represent how many times more sound you have, not how much more you've added. So +3dB means you've doubled the amount of sound. +3dB again means you've doubled again (so x4). -3dB is half as much sound. So a volume of negative 3dB is half as much sound as the minimum a person can hear. |
Clicking "x" and clicking to close, why do they not immediately close the applications? | Clicking the X sends as message to the program the basically says, "Program, please close yourself at the earliest convenient opportunity." If the program in running slowly for some reason, then it might take some time for it to close itself. So you might ask why the OS doesn't just force the program to close when you hit the X, and it's because the program might need to do some special stuff before closing, like prompt you to save the currently open file, or gracefully close network connections. | Actual ELI5: Because the programs are busy doing things, and if you click shut down they get a chance to finish what they are doing. If you hold the power button down they get cut off in the middle, which can mess things up if they are doing something important. |
The science behind smells (like food) sticking to you or your clothes | Smell is just really really little bits of stuff that float through the air and end up in your nose, where specialized cells can detect them. Sometimes those little pieces land on your clothes instead, and later on they fall back off and float around until they land in someone else’s nose | Some research suggests that quantum mechanics plays a role in how we detect smells: _URL_0_ |
What happened to the bodies of executed Pirates during the golden age of Piracy? | Most executed pirates ended up buried in unmarked graves. If the place of hanging was near the shore, probably ended up being somewhere near the shallows. If multiple people are hanged at the same time, there's a good chance of them being burried all together in the same hole. If the government wished to make an example of the pirates to public, they took the bodies and gibbeted them with chains and/or iron hoops. Dipping in tar also is possible in this operation. The gibbited body is placed in a very visible public place, often in sight of maritime commerce areas. Once the body has been there for a while and rotted away significantly, *then* it was probably buried in an unmarked grave like previously mentioned. William Kidd and John Rackham (and two of his crew) encountered gibbeting off the top of my head. | This is actually a rather commonly asked question - and luckily for you, we have a pirate expert who's done an AMA that can answer most of these questions! Let me link a few threads that might help :) * [Wednesday AMA: I'm eternalkerri, moderator and Pirate analyst. Ask me questions about Pirates!](_URL_3_) * [Sources on Pirates/Caribbean in late 1600s](_URL_1_) * [What can you tell me about pirates?](_URL_0_) * [I have a few questions about pirates. (Arrr!)](_URL_2_) Hope those help! :) |
What causes a tree to split from its main trunk into multiple branches? | This seems like a good place to mention Leonardo da Vinci's observation that the total cross-sectional area of a tree remains the same from the trunk up to the tips of the branches, which led to the "pipe model theory" of plant vasculature, which says that a unit area of leaf is supported by a unit area of conducting sapwood (i.e., we may conceive of a tree as a bundle of pipes running from root to leaves). | The dark inner part is called heartwood. It is not the same as phloem. Phloem is on the outside of the trunk just beneath the bark. All of the wood that makes up the actual trunk is xylem. The outer xylem (lighter colored in your picture and in many other tree species) is the active xylem that was still transporting water when the tree was cut. This is called sapwood. The heartwood that makes up the inner trunk is old xylem from previous years of growth that has become non-functional as the tree grew. The tree loads resins, phenolics, and organic acids into these non-functional vessels that keep bacteria and fungi from rotting them and also give the heartwood its different color and properties. |
Why are birds and bees associated with talking to kids about sex? | Usually the first thing you learn about procreation is that of plants (flowers). The German expression is, appropriately, “Bienen und Blümchen”, which translates to “bees and flowers”. There are male and female plants, and the pollen is the equivalent to sperm, while the blossom is the equivalent to the female parts, leading the pollen to the egg cell. Some plants are pollinated by birds instead of (or in addition to?) insects. So “talking about the birds and the bees” (or the bees and the flowers) is a euphemism for talking about procreation/sexuality. | The saying came from a Broadway show Paris by Cole Porter. He was signifying that Birds do it and bees do it but we don’t talk about it. Along with other blunt lyrics. He was trying to get past the taboo of sex in culture. Such an excellent playwright! Ahead of his time. |
where do birthmarks come from? | There are two types of birthmarks. Pigmented birthmarks result from when there is an excess of skin pigment cells, the cells that give your skin colour, in one place. Examples of these would include moles, café au lait spots, and Mongolian spots. Vascular birthmarks are from an increased amount of blood vessels in a given location. These are red, such as salmon patches and port-wine stains. It is still unknown why birthmarks form. Here are a few examples of birthmarks, I'm sure there are many more types, but these are some of the more common ones. [Café au lait spot](_URL_2_) NSFW?[Mongolian spot](_URL_3_) [Salmon patch](_URL_0_) [Port-wine stain](_URL_1_) (Prominent patch on his head) _URL_4_ Edit; nsfw Edit: redux; more info | We don't know why birthmarks occur. There are two types. Pigmented birthmarks are caused by an excess of skin pigment in the area while vascular birthmarks are caused by blood vessels clustering up. Vascular birthmarks are not hereditary, it's just an imbalance. Pigmented are not necessarily genetic but the condition that causes them to occur may be. |
Without getting all anti-religion about it, what's the point of swearing in witnesses in a court of law? Why not just make all lying in court cases perjury (and illegal)? ELI5 | It's a formality that has its origins in medieval times. Back in the day it was common to brand criminals on their right hand as part of their punishment. A convict could never testify in court, because it was assumed that once a crook, always a crook. Now, think of how an oath is administered: the judge asks the witness to raise their right hand and put their left hand on a holy book. This did two things for the medieval courts. First, by swearing on a Bible, it established the witness' reliability and honesty-- cause no one would ever lie under the threat of eternal punishment, right? Second, by raising the right hand, it showed that the witness was not a convicted felon, and thus competent to testify. Nowadays, you aren't required to swear an oath, though it's most common to do so on a Bible. Instead, you can *affirm* to tell the truth, which is the same thing, minus the Bible or other religious text. | It is a way to prevent coerced confessions. If you can be compelled to give testimony against yourself, you can be punished for not testifying. Imagine if there weren't such a protection: Judge: Tell us who your partners were in the robbery. Defendant: I didn't commit a robbery! I have no partners! Judge: I don't believe you. I'm holding you in contempt of court. You get to stay in jail until you are ready to tell us the truth. |
What is Gonzo journalism, and what makes it different from conventional journalism? | News stories used to be written in a fairly dry and detached style - the "who, what, when, where, and why" style of reporting, written in the third-person past tense. Gonzo journalism as produced by Tom Wolfe and Hunter Thompson is a style where the journalist is much more involved in the story. So the journalist might write from the point of view of his/her personal experiences of the story as it unfolds, often written in the first-person present tense and often with the journalist him/herself written into the story. It makes it a much more personal and intimate view of a story. Some of the stylistic effects are still used in journalism today. | Starting around 1902, various Progressive activists and writers tried to make journalism respectable and the newspaper trades became increasingly professionalized. This process accelerated after 1908 as the first formal "journalism school" was founded at University of Missouri. By 1917, the sensationalisitc and muckracking styles of newpaper writing were falling out of favor, although I'm sure the war effort helped with this somewhat. During the 1920s and 1930s journalism became increasingly professionalized, and by the 1950s many (if not most) professional newspaper journalists are graduates of collegiate journalism schools. J-schools tended to teach a very specific style of writing narrative which is often presented (somewhat misleadingly) as "neutral". For further reading, I suggest *Journalism, 1908: Birth of a Profession* as a good scholarly source for current understanding on the changes that newspapers and the people writing for them underwent in the early 20th century. |
why are boxers told to spit out their water as opposed to actually drinking it in between rounds? | I know of two reasons. 1. gets the blood out of your mouth if you've been hit. 2. Boxers hydrate a lot before a match. You don't want a full stomach of anything b/c you'll puke if you're hit in the stomach. | They're wetting their mouths and thinning out their saliva. They don't want to drink too much and get waterlogged, which can hamper their performance. |
Where does the expression 'break a leg' come from? | Check out this answer by /u/caffarelli and /u/AshkenazeeYankee: [When/how was the phrase: 'Break a leg' first coined?](_URL_0_) TL;DR: we don't know, but there are some interesting theories about it. EDIT: fixed circular link | It's a theatrical term from a long time ago. It refers to an actor's reaction to the crowd's applause for him for his performance at the end of the play. In acknowledging the audience's appreciation he would bow and genuflect to them; bending or "breaking" a leg. Hence before a performance an actor would be told "hope you (have to) break a leg", i.e. do such a good job that the audience's reaction would be such that it required him bowing at the end of the play. |
where do tv shows & movies get music? | A lot of shows and movies hire a composer who , often working with director, creates a majority of the background music or main themes - like John Murphy for 28 days later. And for the other music in the show or movie, yeah probably whatever the director/producers want. Sometimes due to studio contracts requiring that something is 'plugged' | Their job is to look for this kind of music. No matter who you are, you're bound to find good indie or underground music if you work 8+ hours a day looking for it and producing it |
To what extent did the Russians colonize Alaska? (and other Alaskan questions) | The Russians never had any large colonial localities, no. The area was used almost fully for natural resources or the fur trade, and was not that useful or profitable (a reason the Russians sold it off). The number of Russian settlers in Alaska (a huge territory) never surpassed 300 or 400. This was not enough to convert large numbers of locals despite some missionaries being sent. | While there’s always more to say on the subject, you might be interested in this previous answer by u/The_Alaskan to [How protected was Alaska and Bering Strait during the Cold War?](_URL_0_). |
How does dumping a bucket of water on your head help the ALS cause? | It's a combination awareness/donation drive. "Dude, why the hell did you just dump a bucket of icewater on your head!?" "For ALS." "What's ALS?" "The reason Steven Hawking's paralyzed." "Oh, that thing. Yeah, that sucks." "Yes it does. Wanna donate for a cure? If not, you've gotta dump a bucket on your head too." "Well, OK. Sounds like a good cause." | It doesn't go to the brain because the plumbing doesn't work that way. You can't pass water through electric wires. It doesn't reach the eardrum (usually) because of surface tension. Basically, your ear is filled with lots of hairs and earwax that increase the surface area and keep the water from penetrating too deep. It is possible to get water to the ear drum though. You just have to use a dropper or a hose to put it there. |
What is the "reptilian" part of the brain and why is it labeled as such? | A better way to say it would be "This is the part of your brain that has changed very little and still has much of the same function as the equivalent area in other amniote tetrapods (everything that shares a common ancestor with both reptiles and us)." These are the areas of your brain that accomplish every deep, basic functions of homeostasis and very basic information processing. They haven't changed that much because they are already very well adapted for their complex function, and other parts of the brain have seen more changes in response to differing needs in organisms (in humans, for example, we have radically more cerebrum with a lot of folds to increase surface area because that's the primary area where our abstract and complex thoughts occur.) | Here's [last year's answer to the same question](_URL_0_). It is the meninges which is basically tissue that wraps around the outside of the brain. |
How does an electric kettle know when to switch off? | The simplest ones are mechanical and use a bimetallic thermostat element unit at the bottom of the kettle. It consists of a disc of two different metals bonded tightly together, one of which expands when it reaches a set temperature. That click can be heard when it shuts off and later when the pot cools back down. | Taking the question further, how about an electric kettle? |
Why do our bodies first make us hungry instead of using excess fat? | Your body converts food to excess fat; this is for things like insulation, energy reserves, etc, before it begins to break down proteins and muscles. To convert food to fat, it has to first be digested then converted. If it used the "excess" fat first, it would have to undo all of that. What that would imply is that it converts (requiring energy) food to fat, then convert it from fat to energy (again, not a 100% efficient mechanism, as the conversion requires energy). That is a wildly inefficient process, where it is much easier to say "I'm hungry" and eat, then convert the excess to fat. | Let's think about this from an evolutionary perspective. Way back in the day, (like way way way back) humans struggled for food just like every other animal. It was to our species evolutionary advantage to pursue food that would keep us full longer, or provide more energy than other food options. Fats, are 9 calories per gram compared to proteins and carbs that are 4 calories. Humans that preferred fats and craved them, had a higher chance of survival and passing on the fat craving trait. Fast forward to present day where food is plentiful. We are still programmed to eat high calorie foods just in case we won't find food for a week! |
Why do people blackout when they drink too much? | Blackouts happens because alcohol affects the hippocampus (the memory part of our brain.) Blackouts usually happens when you consume alcohol very quickly like shots. The hippocampus essentially shuts down during a blackout and no longer creates memories. Think of it like a tivo. Your tv shows still runs as time goes by, but the recording has stopped. | What makes you think that you wouldn't? Being blackout drunk is a result of alcohol interfering with your ability to create and process memories, and many of your other cognitive functions continue unabated, if somewhat impaired. |
Why is it so hard to keep endangered species from going extinct? Can't we just capture and inseminate them to create more? | You will also have to reintroduce the created animals back into their natural habitat and ensure whatever was wiping them out in the first place doesn't simply wipe out the new individuals. | Because they too would be an invasive species. Doing what you recommend would eventually lead to a complete replacement of an ecosystem with the animals and plant from a different one. |
Why and how wind works? | The sun is the driver of winds. For various reasons, the sun heats up some parts of the earth quicker than others. The air above those warmer parts is heated. This cause the air to expand, making it less dense, causing it to 'float' above other, cooler air. This cooler air moves in to replace the warmer air that has risen. This movement of air is what we call 'wind'. Of course, there is humidity, latent heat and the coriolis force, but that is for ELI Colledge Student. | Wind is the movement of air from high pressure to low pressure. If you measure the pressure in two locations and notice a difference, you can use that to determine how much wind will be around. Using many locations, you can get a better idea of direction and speed. |
Who were the last hunter-gatherer communities in Europe? | If you include hunter-horticulturist tribal groups into the list, rather than strict nomadic hunter-gathering, there remained groups of Montenegrins following such traditional lifestyles up until the early 20th century. By the time the Balkan Wars ended and the area was absorbed into Yugoslavia, the last of the communities had given up for more modern ways. | I do not believe this question can be answered unless you stipulate a time and a group. "Before Western colonizers" in the New World likely encompasses 15,000 years and millions of natives. Subsistence patterns varied widely among these people. There is considerable debate among anthropologists about how much free time hunter-gatherers had. As a starting point check out "The Original Affluent Society" [here](_URL_4_). If you were to stipulate a tribe and a period of time, we might be able to assist. I suggest you narrow your question and also try in /r/AskAnthropology. As an afterthought, the affluent hunter gatherer notion was argued by Marshall Sahlins. You might look at his work. |
Why did major Hollywood movies in the 1980s nearly always seem to have extensive (10-15) minute nude sex scenes with sappy instrumental music playing in the background? | Well, there were several factors at play. First of all, there was no internet at that time. This meant that pornography was primarily distrubuted through magazine sales and video. Video being the increasingly popular choice. However, the movie industry was quick to capitalize on the fact that sex sells, and that X-rated video tapes still carried a negative stigma. Therefore, they simply integrated sex/nudity into R rated movies. Obviously, respecting censor guidelines. Porky's, Revenge of the Nerds, and Lifeforce were a few of my favorites. | The only films in which they really have sex are porn films. Remember that while a film may look like one continuous take it's actually several different takes of the same scene from different angles. Sometimes they also, rather than film the whole scene, will just film specific parts. This is all edited together in post production with a good editor. There is nothing sexy about doing a sex scene as it's done in front of a huge group of people including director, camera man, DOP, sound operator etc. The guys parts are usually taped down to ensure that nothing "happens" and the girl will usually wear a small covering as well. Bearing in mind that with a great editor anything can look realistic. Hope this helps. Source: _URL_0_ |
why does looking at the road keep you from getting carsick? | Motion sickness is when your eyes and your inner ear are experiencing different things. Sitting in the back seat of a car, you're mostly seeing the inside of the car which isn't moving as far as your eyes can tell. But your inner ear is sensing all kinds of movement. So your eyes say you're not moving, your inner ear says you are, and boom you're gonna throw up. In the front seat, you generally have a much better view of the road so your eyes and inner ear are more in sync. | It's largely because you're exposed to the outside, and especially the wind. You're not experiencing the speed with more than one sense, rather than just your sight. |
Can a binary star system have a center of mass whose escape velocity is > c? Would this be a black hole? | At the barycenter (center of mass) of binary stars the gravity is zero. It's the equilibrium point between both stars. From that point two so-called Roche lobes spread out in the directions of the two stars. The Roche lobe is the volume of gravitational influence where the strength of gravity by one of the stars “overwhelms” the gravitational strength of the other star. | If you were to compress all the mass in the milky way into a black hole it would have a radius of about 0.2 lightyears. |
What is the medium between synapses? And what force if there is any, pushing neurotransmitters into receptors? | The synaptic cleft, which is the space between the pre- and post-synaptic structures, contain extracellular fluid which in many ways resemble the fluid surrounding the rest of the neurons. It is roughly 20-40 nm in width, which is just shy of the size of the vesicles that release neurotransmitters (50-250 nm) [source](_URL_0_). There is no force 'pushing' neurotransmitters, rather all transport post release happens by diffusion. I.e.: the concentration of neurotransmitters in the released vesicle is so high that the neurotransmitters automatically disperse throughout the synaptic cleft. If you want to read up on either the [synaptic cleft](_URL_2_) or [diffusion](_URL_1_) wikipedia is a great place! | Though not exactly what you are asking the way I understand your description, your title seems to imply that neurons don't touch at all in the synapses. They don't exchange any meaningful information through direct contact, but they do indeed touch each other and this is integral to the function of the synapses. Without any contact at all, very little of the extremely small amount of transmitter released would be able to diffuse to the post-synaptic membrane and bind to receptors. This organizes the synapses and means that how and where two neurons make a synapse isn't random; the neurons actively hold on to (through cell adhesion molecules) the neuron that they mean to make a synapse with. It looks a bit like [this](_URL_0_) |
Why do hatchbacks have rear wipers but sedans don't? | The closer the rear window is to a 90degree angle, the more water will "stick" to it, thus requiring wipers to enable better visibility. It is all about shape. Hatchbacks rear window tend to form a greater angle ( they are standing further straight up). While sedans usually have a more smooth and lower angle which will enable the air to push the water off the window. | The aerodynamics of all cars creates a bubble of air behind them causing a loop affect when it rains. This loop effect causes rain to splash back on to the rear of the vehicle. In an SUV or other trunk less car, this means it splashes onto the rear windows. In a normal coupe or sedan, the rear is the trunk which gets hit the most. So essentially it just not a necessary expense to add to sedan like cars. |
Why can we recognise a person talking a certain language but we can't speak it? | Because a language isn't just the words and how they're ordered, it's how phenomes and individual consonant and vowel sounds are governed. It's the speed at which it's delivered. Even if we don't understand the content of what someone says, it's how they say it that we identify. | because people developed languages over long amounts of time far separated from each other and languages naturally change over time. If you don't interact much with a group for a thousand years, you'll end up speaking very differently from them. |
Why is it we pass out from standing too long with our knees locked, but not when we are lying down? | Locking your knees causes issues with blood flow which in turn causes you to pass out. You don't lock your knees when you're laying down so it doesn't really apply. | Locking your knees reduces circulation and can cause gravitational blood pooling in your lower extremities. This can remove a large amount of oxygen from circulation, which could cause your brain to activate a sort of fail-safe by shutting down non-essential systems in order to keep your heart, lungs, and brain functional. This causes you to pass out. On a side note, I copy/pasted your question into Google, and two ELI5 posts popped up asking the same thing, as well as several medical websites answering this exact question. |
What are the nations of power today? Which are our allies, neutral, our enemies, with a brief 1 or 2 sentence description as to why? (Non political) | We have no allies. We are the greatest nation. All other nations learn from us how to be perfectly efficient and good to citizens. Our great and powerful leader is the only ally we need. Long live Kim, glory to Korea. | Military, intelligence, and foreign policy: virtually all of the power. Law enforcement and social issues: some power. Economic issues: practically no power at all. |
Why are most humans afraid of cockroaches when they are relatively harmless and have no poison/venom to hurt us? | It’s what they’re associated with. Cockroaches are often found in disgusting places and by extension are perceived to be disgusting. People don’t necessarily want to be near them incase they come in contact with whatever germs/bacteria/disease they may carry. It also doesn’t help that they can fly. | Probably because many spiders are venemous, and so, like snakes, people evolved to fear them. There aren't very many creatures common throughout the world which can poison us, spiders and snakes are the only ones which come to mind really. |
Why don't we get Deep Vein Thrombosis after 8 hours of sleep? | Most people move around quite a bit when sleeping. Enough to keep blood moving through the veins, anyway. However, people confined to bed rest are at heightened risk for deep vein thrombosis. | A certain sleep writer suggests it's because there is a metabolitic release timed to coincide with the early part of sleep intended to for the heavy lifting your lymphatic and endocrine systems will do in the early part of sleep. Apparently this is the "second wind" we feel at approximately 10pm, and being asleep at this point results in higher quality sleep. This is the only thing I've come up with on the topic so far. It seams reasonable that one's body would benefit from a release of energy for homonal/repair/immune function that does happen during sleep; however, I traced the reference chain back finally back to an Ayurvedic medicine writer, and haven't found any peer-reviewed empirical research on the topic (yet), so I think the jury is still out on this one. |
What is the Hajj and how does a stampede occur? | All Muslims are required to take at least one pilgrimage to Mecca in their lifetimes. Mecca is the center of Islam and its holiest city. I think the day the stampede happened was a holy day so that's why there were so many people there but I'm not sure. There were roughly 2 million people there and there is very little crowd control. So at a convergence point, when all of these people are coming together, something can happen that can cause a crowd surge, which is what happened | There are generally three requirements for the hajj: * Mental and intellectual maturity, so one can understand the significance of the pilgrimage * proper physical health to facilitate the pilgrimage * proper financial conditions to facilitate the pilgrimage. So very simply, the Hajj though mandatory is only for those capable of making the journey. Those too poor to do so, than as now, are exempt. Edit: for some textual grounding to this claim [3:27]( _URL_0_) > In it are clear signs [such as] the standing place of Abraham. And whoever enters it shall be safe. And [due] to Allah from the people is a pilgrimage to the House - **for whoever is able to find thereto a way**. But whoever disbelieves - then indeed, Allah is free from need of the worlds. |
If light has no mass, than how can it be sucked into black holes? | Historically, gravity was thought of as a force between massive objects. Einstein's theory of general relativity trumped that with the idea that gravity is actually caused by the interaction between space and something called the "stress-energy tensor", which basically measures the density of energy (of which mass is one type) in space. When mass/energy is present in a region, the space around it "bends". This changes how objects (including photons!) move through that space, by literally changing the shape of paths through the space. What makes black holes special is that, within a certain distance (the Schwarzschild radius), the space is so bent that, although there are paths that go in, there are no paths going out. Even light can't get out, because there *is no out* from inside the event horizon of a black hole. | Black holes don't have infinite mass. Most have a mass comparable to our sun, although there are supermassive black holes a billion times the mass. It doesn't really make sense to use special relativity, which covers things moving in the absence of gravity or other forces, to describe something under the influence of an extremely strong gravitational source. General relativity covers this quite well. |
Why do some t-shirts drape so well while others just, well... you know, suck? | When they make better quality clothes, they make sure the fabric is going the right direction. Look at the knit on the crappy t-shirt. The ribs are probably running on an angle. The better one it will be straight. | not entirely sure from this, can't see the shirts, but have seen similar situations. some fabrics, especially knits but also others, have a direction to them, the fabric is made in a way that the way the fibers are put together is not identical in all directions, like vertical vs horizontal, these tend to also stretch and shrink in non symmetrical ways. it's possible that you're shirts are made with fabric like that,but cut in different directions. |
What type of foods would the Vikings have served at banquets and celebrations? | I haven't posted here before but I've been reading up on the Viking age for a while now. Most of the books I've read have the same answers but the one I've read the most and use as my source is The Viking Age: the Early Histories, Manners, and Customs of the Ancestors of the English Speaking Nations Vol.1 by Paul Chaillu Du Ohaillu. You can find it on Amazon. Some feasts you would have to bring your own food, some would have everything supplied by the Gođi, either way the food was mostly the same. Usually some form of oxen, horse, sheep or boar would be killed and hung by its feet to bleed out and then boiled. Mead was served obviously but also Skyr, a type of milk (usually goat) that was fermented (? Not quite clear on how it was made but people still eat it) to the point of being thicker than yogurt and sometimes including cottage cheese like clumps. Some sort of bread also and dried fish, although dried fish was more akin to a trail meal than something you'd eat at a celebration. Hope this helps. | Not to discourage further answers, but in case you don't get one, you might be interested in /u/Aerandir's answer to a question [here](_URL_0_): > Stockfish would have been the normal food for raiding expeditions, which is not particularly what I would regard as a 'power dish'. Normally people would have eaten cereal stews and porridges, lots of fish and some meat. If you go out raiding perhaps more than at home, given that there are no concerns for preserving animals for secondary products (wool, traction, milk). Boar and pig would be particularly popular, whenever a Viking would be able to get it. |
Since stars are constantly fusing their way up the periodic table, is the universe expending a limited supply of lighter elements? Could this outpace entropy/heat death? | Stars only fuse up to iron. Supernovae make the heavier elements. | Are you talking about solar fusion? Because fusion in a sun most certainly can go beyond iron, but such situations are fairly uncommon, and highly unstable. In solar time, a sun fusing heavier-than-iron elements has weeks, days, or hours to live before it parties like it's 1999 sometime. That's pretty brief. The [quick](_URL_0_) explanation for iron though is that fusing elements requires energy, and as you go up the table of elements, the heavier they are, the less energy is generated from the fusion. By the time you've reached iron- lots of iron- you're dealing with a star that's near the end of it's life cycle, and as you go past iron you're starting to hit elements that don't fuse on their own; external energy sources are required. This is also why post-iron elements are typically created by super novae. |
Does the mass of the Earth grow via the energy collected by plants or is the biosphere a closed recycling system? | E = mc^2, so a lot of energy is needed to make just a little bit of mass. While the sun's light does give earth some tiny amount of mass-energy, the earth is also constantly radiating heat and other light into space. However the total contribution of mass-energy from light going in and out is (I would guess) likely dwarfed by the small amount of debris that earth picks up from space, in the form of micrometeorites and other tiny space rock/dust things that add a little bit of mass pretty much all of the time. The biosphere is closed in the sense that it doesn't eject matter into space (with exceptions of rocket launches or asteroids knocking stuff up there, which are so rare and small that they hardly count) but energy is constantly flowing in and out in the form of light of various kinds. | It mostly goes into the CO2 that you exhale into the air. Plants then get most of their mass from that same CO2, not the ground that they’re in. |
from a non biassed perspective why do people in the uk say we entered into an illegal war, and the defense against such claims? | The war in Iraq was not authorized by the UN Security Council, hence, an illegal war. To quote Kofi Annan: > From our point of view, from the charter point of view, it was illegal. Afghanistan, have no idea. | Political linguistics. Portraying the war as a 'revolutionary' effort painted the rebels in a heroic light: they were overthrowing the imperialist establishment. This also appealed to a number of people living in Britain, mind; it became lucrative for businesses to sell accessories that referred to the 'revolutionary' cause. (Anything to bash the government with.) However, journalists and government documentation at the time using 'war of independence' at least suggested an alternative to the demonisation of the British regime. If the Americans were deemed to have little to 'revolt' against, which the term 'revolutionary' refers to, a different description suggested their motivation was wanting to become an independent state more than making a stand. (I will say that, as a Brit myself, it usually *is* referred to as the American revolution here, at least colloquially. If anything, 'war of independence' is more an academic term in modernity.) |
What is the connection between the amount of oxygen and the size of insects? | Insects don't have lungs like we do; they intake oxygen and expel carbon dioxide through their skin, in an osmotic process. As a consequence of this, higher oxygen concentrations allow deeper penetration of oxygen into the insect. That means insects can grow larger. So higher oxygen concentration means physics permitting the evolution of larger insects. Lower oxygen concentration means less penetration, and subsequently smaller insects. That's why there were some wickedly huge bugs millions of years ago, because the atmospheric oxygen level was much higher. | Insects respirate through a series of tubes that are connected to the air. They don't breathe the way we do, and their blood doesn't carry oxygen to cells (mostly, there are some midges, for instance, that have hemoglobin). They have a bunch of holes (spiracles) in their exoskeleton that they can open and close. These holes are attached to tubes (trachea) which allows air to flow directly to cells. It isn't a very efficient system, because they are limited by the physics of air diffusion. But it works fairly well for small bodies. When the air has a higher oxygen content, it can penetrate deeper into the body, allowing the insects to grow larger. |
What the hell happened to the History Channel? | The bar has been lowered. I remember TLC and Discovery having educational shows too, and now its all Honey Boo Boo and Dugger the kid diddler. /shame | An insane legal mess. CBS probably sold the exclusive rights to the Late Show to some Canadian company. Allowing Canadian viewers to watch the show on their YouTube channel would violate their contract with the company that has the Canadian rights. |
Why is a cloud gray when raining , but white if not? | Clouds are just little pieces of water in the air, that have grouped up enough to start reflecting light from the sun. At first clouds are white, because they aren't very dense. Light moves through them pretty easily. As clouds gain more water mass, they start blocking some of the light, making the cloud grow darker. Then once heavy enough, the water in the cloud collects enough to rain. The cloud remains darker. | Grey and white are both colors where there is the same amount of light of all colours. Or if you look on a computer screen it is the same amount of red green and blue. The difference is the amount of light or more exactly the different amount of light compare to the surrounding. Look at [this optical illusion](_URL_0_) where square A and B have the same color but the look different because of their surrounding. Clouds are primary lit from above and the thicker the cloud the smaller the amount of light will pass trough it and it will look darker ie grey. |
With the US' transition from analog to digital cable a few years ago, seemingly everyone must have a digital box. Are TV ratings becoming more accurate? | The switch that occurred a few years ago was from analog to digital **broadcast**. This meant that people who received their television over the air - not from the cable company- and who did not have a digital capable television needed to get a digital box. People who watch via a broadcast digital signal are still not any more "trackable" in terms of what they are watching than they were before. | That and many other factors. Lighting, color grading etc. Also, i remember back in the day when TV was still analog, there’s a certain kind of feel to each channel. |
AskHistorians, how were castles from the Medieval period built? | I hope this doesn't get deleted (cause it doesn't exactly fit Askhistorians rules, but it's too good to be ignored): some guys in France are building a 13th century castle, using tools and techniques from the era: _URL_0_ the whole thing is supposed to take a grand total of 25 years and can be visited. | The Irish Tower House, amongst the smallest of structure we'd call a castle, may have been built for as little as £10. In 1429 King Henry VI introduced a measure granting £10 to any man in the English controlled section of Ireland (the Pale) who would construct one. If one assumes the flurry of tower house building (several thousand) was set off by this, the subsidy probably covered a large proportion of the cost, though by no means were they only built by English loyalists. For those unfamiliar, these were relatively simple rectangular plans of 4-5 stories and a minimum of 20'x16', often with a small curtain wall. Source: Sweetman, P.D., 2005, Medieval Castles of Ireland |
Why do only some plants make tea? | If you want to be proper about it, you can only make "tea" from [Camellia sinensis](_URL_0_). All your other 'herbal teas' are called "tisanes". You can take pretty much any plant, dry it & cut it up & then soak it in hot/boiling water. If you want, you could try drinking it. The problem is that not all of them are going to taste good & many of them will be poisonous. The stuff we make tea out of are the plants that taste good, are safe to use and/or have desirable medicinal effects. | Could you narrow down your question geographically? Tea wasn't introduced to Europe until the 1600s. In Central Asia they would have been drinking fermented mare's milk, Australian aborigines were drinking flower nectar, Africans were drinking fermented palm sap... |
How to calculate the Domain and Range of a Function? | For a function f(x)=y : The Domain is all the values x is allowed to be. The Range is all the values y can be, considering all allowed x. For example: f(x)=1/(x^(2)) has a Domain of "x is not equal to 0" (since it would be undefined due to division by zero) and a Range of y > 0 since no value of x gives a negative or zero value from the function, but you can get any positive real number result you want. | Domain is the set (you can think of this as a list, I guess) of all possible inputs to a functions; range is the set of all possible outputs. |
Did early humans organize into family units like modern humans do? | The only real answer is that we can't really know. [Kinship](_URL_0_) structures range wildly all over the world. The only thing one could say with any amount of confidence is that that children were taken care of to some degree, but by who we have no idea. | Hi, this is an anthropology question. There are a few anthropologists here, but it may be worth x-posting to their usual hangouts: /r/AskAnthropology and /r/AskScience (Social Sciences).. |
Clowns are typically meant to be silly and fun, why is the fear of them so widespread? Does that fear have an origin? | Clowns are [a kind of trickster](_URL_0_), which in myth and legend can be both funny and scary, foolish and cunning (think Loki, Pied Piper, Puck, etc.). They break rules and are unpredictable. It also has been noted that the clown's painted faces are "[familiar, but off](_URL_2_)", distorted, and hide their real faces-- all of which lends to a disturbing presence. [Evil clowns](_URL_1_) date back at least to Edgar Allan Poe's short 1849 story, "Hop-Frog" and appear in operas form the 1880s and 90s, eventually making its way into comics as the Joker in the 1940s. Further, serial killer and amateur clown John Wayne Gacy and Stephen King's novel "It" helped to further push the idea of evil clowns into the popular consciousness. | As a circus clown, I take exception to your friend's assertion. Circus clowning has roots as far back as tribal shamanism. Circus clowning also took a lot from the Italian Commedia dell'arte theatrical tradition of the 16th century. These masked "stock characters" were common from troupe to troupe, and allowed for the development of the classic circus archetypes over time. For example, the French "harlequin" style clown is a development of the stock character Arlecchino. A good intro look at this topic can be found in: _URL_0_ I am a Ringling Brother's Clown College trained clown who has been clowning for over 15 years. |
In his account of 13th century warfare in the Levant, Jean de Joinville mentions having a spare sword. Was this common? | Although /u/Valkine might wish to add to it, [this is an excellent breakdown of the cost of military arms and armour](_URL_1_). Jean de Joinville was a prestigious noble in thirteenth-century France, after he lost his war-chest for the campaign (after he was captured by the Saracens) he received a grant of 20,000 *livre tournois* which covered the replacement of his arms, armour, horses, and to resupply and pay his own men. It wasn't uncommon for nobles and knights to have multiple horses, which could cost the income of a village (£40 p/a), to have a few swords wasn't anything particularly special. | Yes! Great question I want to know too. Follow-up, how did the nobility of the sword become established in France? Paging /u/idjet perhaps? |
Why does confetti make the video quality go waaay down in a video? | video compression works by identifying portions of a video frame which stay the same between the previous frame and current one, or by identifying portions which haven't changed in appearance much but have moved over a few pixels. taking advantage of temporal features like this is why videos are much smaller than a million jpegs and an mp3. confetti fucks this all up because each piece is super small and moves more or less randomly, giving the video compression algorithm very few reference points between frames which stay the same. thus, there are no temporal reference points and the video encoder must store each frame without any carried-over information from the previous one. in order to keep the video's size and bandwidth within limits, the encoder must reduce the quality of these frames. | Two possible reasons: * The television you're watching is an LCD display with [motion interpolation](_URL_0_) active (often in conjunction with marketing as a "120-Hz" TV). The video circuitry in the TV is introducing more generated frames in between the actual frames, making it more fluid and less film-like. You can disable this so the broadcast looks like you would expect. Motion interpolation can make content feel like a soap opera or a video game. * You are watching [pan-and-scan](_URL_1_) programming. Sometimes, a wide movie may be formatted to a more square format to avoid the black bars that come with letterboxing. The view may artificially pan across a normally pan-less frame to show more of the frame. This artificial pan might be done at a video frame rate that is higher and smoother than the usual film frame rate of the original. |
Why Nitrite is still used as a conservative in all processed meats if it's a known carcinogen ? | Not _all_ processed meats. But anyway: There are known carcinogens in almost all food. There is no 'zero-tolerance' policy here, it's no so much a matter of whether it's a carcinogen or not but a matter of whether it creates a statistically-significant increase in cancer rates in the concentrations that it occurs in food. Nitrate in themselves aren't the danger here as much as the nitrosamines they produce. But nitrosamines are also [produced endogenously](_URL_0_) in your body to some extent as well. Also, ascorbic acid/vitamin C is also added these days, which helps [inhibit nitrosamine formation](_URL_3_). It's used as a preservative in specific products (cured meats, cheeses), with set limits, mainly to [inhibit the growth](_URL_2_) of [C. Botulinum](_URL_1_), which causes botulism. In the big picture that has been considered a larger danger than the cancer risk. | Well, they're not terribly bad in-themselves (and to a small extent occur naturally in food and in your body). But they can react and form carcinogenic [nitrosamines](_URL_0_) in your stomach, either in your stomach, or if they're heated up. So they're to be avoided, and often replaced by nitrite instead. In most places it's not legal as a preservative except in cured meat products, some cheeses, etc, things that aren't cooked and where botulism is considered a bigger risk. Nitrite preservatives are a [fairly insignificant](_URL_1_) (a few percent) part of the average dietary intake of nitrites, most of which comes from vegetables - even with salami fans. |
In movie, sieges on castles often depict arrows randomly flying into the crowds. Wouldn't they be more likely to aim at those carrying the siege equipment? How were those men even able to make it to the castle walls with such targets on them? | Hi, hopefully one of the military flairs will drop by to address the specific scenario of firing on attackers in a siege, but meanwhile, you may be interested in a couple of threads addressing the general strategy of firing in volleys * [Did those showers of arrows really exist?](_URL_5_) - featuring /u/MI13 * [Why was volley fire prefered with muskets and arrows vs. allowing everyone to fire at will?](_URL_6_) - featuring /u/bigbluepanda | Movies pretend that archers aim at a specific target while instead they just went for a general distance. Edit: or really just to build tension. |
Do prisms break apart sunlight into all wavelengths? | I'm not sure what you're asking because the only answer I can think of is "yes that's exactly what prisms do". It's because different wavelengths are refracted (bent) at different angles. Even invisible to the human eye wavelengths do this, there's nothing special about ROYGBIV. | The light coming from the sun is mostly due to thermal radiation, which is caused passively by hot materials. The hotter it is, the shorter the average wavelength of the light will be. The problem is that it is much hotter than a lightbulb filament could be, giving it a [spectrum which can't be matched by incadescent lights.](_URL_1_) However, it is possible to mimic the spectrum of the sunlight using LEDs or fluorescent lamps. They do that by first producing light of short wavelength, using dyes to turn that a bunch of other wavelengths. the spectrum of the sunlight. Those lights just are not very common, as most people prefer spectrums similar to what incadescent bulbs emit. |
How long would it have taken for the moon to coalesce into a sphere after it was separated from the earth? | Can I add a request? History Channel's "The Universe" claims that the moon formed in just a few months after the Big Splat. How can that possibly be true? | You kind of got it right but the Command Module never went to the moon, that was the job of the [Lunar Module](_URL_0_). So the Command Module waited in orbit while the Lunar Module went down. And the Lunar Module had it's own fuel and rockets (according to wikipedia 18000 lbs/8200 kg for landing on the moon and 5187 lbs/2353 kg to get back up to the Command Module). If you look at [this](_URL_1_) cutaway you can see that the Lunar Module really was in two parts and the bottom part was left on the moon when they went back up. |
Why do areas like the Persian Gulf and Russian Urals have vast amounts of oil, while other areas like Japan and the Amazon have none? Geologically what is different about these areas? | So, first off, there is a ton of oil in a lot of places, it's mostly a matter of how easy and cheap it is to get to and extract. Shale oil (colloquially called "tight oil") is so bound up in the rocks its found in that, prior to fracking, there was no easy, cheap way to get to this oil. The oil in the middle east, north Caucasus, and the Urals tends to be easier to get to mostly because the oil is sitting at a depth and within rock formations that make it easy to drill to and extract with simple, vertical wells. | There are small ecosystems that *do* rely on the presence of crude oil. The one which comes to mind is bacteria that comsume the oil. For example, the Gulf of Mexico and the surrounding terrestrial areas see a lot of natural oil seeps, and there are actually bacterial fauna present whose trophic niche is to digest the oil suspended in the waters. It's thought that these bacteria provided huge damage-control to the deep-water horizon blowout with vast swathes of oil being digested - the the ideal warm waters of the Gulf and bountiful food causing a large spike in the population. |
Did Ayn Rand have any impact at all on philosophy or political theory? | Can you clarify what you're looking for? Rand/objectivism's intellectual impact hasn't been seen in philosophy but she has been influential on a number of policy makers. I'm not sure however if that sort of practical as opposed to academic answer is what you're looking for. I like this answer from /r/askphilosophy _URL_0_ Tl;dr Essentially she's had no impact on academic philosophy but (disclaimer to note that I'm not a supporter of Rand's views) sometimes here works/objectivism can be treated as straw men which is by nature problematic. She makes serious philosophical claims and i'm guessing anyone who says here attempts at philosophy are relegated to the fiction section is trafficking in an urban legend. That being said there are clear problems with her work that help explain why she's not treated as a major/important/sometimes even serious philosopher. | Objectivism was Ayn Rand's belief that the pursuit of one's self interest was always the most moral choice, and the only socioeconomic system which could allow for this pursuit of self interest was free market capitalism. The notion that self-interest is the ultimate moral good is a very right winged idea. Furthermore, unrestrained free-market capitalism gives *a lot* of people pauses, as free-market capitalism is a blank check for the haves to treat the have-nots very poorly in pursuit of the so-called morally good "self interest." It doesn't help that academic philosophers have largely rejected Rand's ideas. It's not even particularly hard for the average person to pick apart flaws in extreme free-market libertarianism or "rational self interest," either, so it's very easy for the ideology to attract detractors. Also, she just was not a very entertaining writer. From a literary standpoint, her books are very boring and unenjoyable. |
Why my beard itches when is getting longer but than eventually stops after some time? | You eventually get used to the additional amount of manliness you are exhibiting, therefor it stops itching after a while. | Your hair grows in a cycle with 3 phases. There's a growth phase, a resting phase, and a falling out phase. Your hair on your head has a long growth phase, and shorter other phases. Your facial hair is similar in nature with a longer growth phase. Same with your underarms and other hairy places. Your arms/legs/other parts of your body have shorter growth phases with longer of the other two phases. That's why the hair there seems to always stay so short comparatively. Check out the part where it mentions [Hair-follicle Cycling](_URL_0_) |
Man without bones. How is this humanly possible? Does this man have soft bones or extremely relaxed muscles? [vid inside] | [It's just a extreme case of hypermobility](_URL_0_). He still has bones, just his joints are reallllly mobile. | > [The main misconception about bones then, is that they are made up of dead tissue. This is not true, they have cells, nerves, blood vessels and pain receptors. ](_URL_1_) [The periosteum](_URL_0_) which runs around the outside of bone contains nerves is very sensetive. Even without that the inner structure of the bone is still very well innervated as nerves tend to follow the blood supply. |
So, what happened to all those middle east (and Asia) riots that broke out earlier in the year? | Many of them are still ongoing; the media has turned its attention elsewhere. [wiki](_URL_0_) There is a breakdown on wikipedia in the sidebar where it says "status" EDIT: [Another summary in handy chart form. Scroll up a little bit for a map.](_URL_0_#Summary_of_protests_by_country) | In Tunisia, protests happened, and the government almost immediately collapsed. Then in Egypt, protests happened, and the government fought them for a while, until the army said "we won't attack protesters", and the government collapsed. Then in Libya, protests happened, the government fought them, and so did the army. But then the Arab League and the UN Security Council intervened, and it became a proper civil war, instead of just a massacre of civilians. Then in Syria, protests happened, the government fought them, and so did the army. The Arab League and the UN Security Council are trying to intervene, but Russia and China are blocking resolutions; meaning it's essentially just a massacre. |
What is Aum Shinrikyo? What do they believe/work towards? | They were a sort of Buddhist doomsday cult who were led by a man named Shoko Asahara, a spiritualist and a con man. They were responsible for the Sarin gas attack on the Tokyo subway system in the late 1990s. I don't think they exist under that name anymore, I seem to remember reading about them rebranding themselves as Aleph following Asahara's conviction. I used to be very interested in them and read everything I could find, but it's been a while since I last thought about them. These are the basics as I recall them though. | Initially, the Japanese government wanted to dissolve the cult, and stripped it of its religious status. However, in 1999, the Public Security Commission, an independent agency, deemed, after the government tried to invoke the Antisubversive Activities Law, the cult no longer fulfulled the conditions for dissolution, as it has been declared bankrupt and most of its followers who were wanted by police had been arrested. Consequently, the Diet voted a law allowing for the surveillance of any group having commited mass murder. Source: * ["Government to tighten control on AUM activities"](_URL_1_), *Kyodo*, May 24, 1999 * ["Drafts for Aum control bills unveiled"](_URL_0_), *Japan Times*, October 27, 1999 * ["Japan OKs Laws To Restrain Cult"](_URL_2_), *Associated Press*, December 3, 1999 EDIT: Fixed list formatting |
How does Twitter make its money ? | Yup, twitter is expected to make about $600M from ad revenue in 2013. Closer to $1B in 2014. If they have other revenue streams they have not yet disclosed them, but with the IPO coming up (twitter is going public) a lot more info should be available soon. | Twitter is not a "website". It is a vast networked application that works over many different devices and platforms. It's *interface* is a website - and, in fact, that's but *one* of it's interfaces. And that interface has to talk to many different backends in order to retrieve your information. If you drilled down through Twitter's employees to *only* find the people responsible for the actual web interface, they are a very small number compared to the entire company, even just the engineers. Now let's have a look at video games - yeah, many AAA titles have huge developer forces, but there's no shortage of small, simple games that one person wrote in his or her spare time. The same is true for what you call websites. There are facebooks, which are (again) a huge application that has a web interface, and then there's my mom's website where she shares recipes. In the same way, there's *World of Warcraft*, but there's also *Flappy Bird*. |
How does brain control heart rhythm in people that are from neck down paralyzed? | It doesn't, at least not directly. The heart has its own internal pacing system that takes over. This is actually a real problem around the time of the injury, as the patient may be in shock from their trauma but the body can't manage to mount a high heart rate because the nerves have been severed. The brain can influence certain hormones that affect heart rate and blood pressure, though. Also, breathing is also affected by high spinal cord injuries. The phrenic nerve, which controls most of breathing, receives input from below the C4 area of the spinal cord (roughly speaking). An injury higher than that results in an inability to breathe, and the person will be ventilator-dependent. | Seizures start in the brain and send electrical signals to the muscles. But the heart has its own separate electrical system. |
Why do saxophones have bells even though the sound produced doesn't necessarily disperse through the bell? | From what I can speculate, the whole horns' shape effects the sound. While having holes opened effects the size of the path the air/sound waves travel, the whole of the instrument still gives resonance to the sound. Play the same exact note in the same octave on a sax as a flute or a recorder and you'll still hear a difference. To be more specific to your question. I think the bell gives the horn a broader sound. Perhaps because it's wider than everything else on the instrument it allows bigger/more sound frequencies. This is mostly speculative, please anyone feel free to correct or add to this. | A saxophone (or similar wind instrument) is only a single tube whose dimensions never change. The pitch is changed by opening holes on the side, which changes the vibrations of the air inside. A trumpet is several tubes connected by valves. Inside each valve is a cylinder with pipes inside it that redirect the air through the pipes connected to it. When the key is in the neutral position, the air passes directly through the valve, and on to the next valve. When the key is depressed, the pipes in the valve redirect the air into a different tube. This tube travels a certain distance and then loops back into the valve, sending the air to the next valve. The overall length of the instrument has changed, increasing the wavelength of the vibrating air, lowering the pitch. Each valve has a different length of "redirect" tube attached to it, so every combination of keys will produce a different note. |
What's the difference between a social worker and a domestic worker? | A domestic worker is someone who does work around the house for their employer(s) - it might include cleaning, cooking, and childcare. This typically requires no formal education, and is often low-paying. In earlier times, they would just call this person a servant, maid, etc. Social work is a broad field that can involve helping people who may be disadvantaged by things like poverty, illness/developmental issues, drug use, etc. Social workers are generally employed by governmental agencies, charitable organizations, hospitals, etc. Social workers often have master's-level qualifications (MSW - Master's in Social Work). | In pre-industrialised agricultural societies, families tend to work their farms as a collective unit. There's no separation between 'work' and 'home'. While young children would stay close to their mother, older children would work doing chores such as fetching water, and as they got older, helping their father if they were physically capable. Since children didn't go to school, and fathers essentially worked from home, children spent much more time with their fathers than they do now. It was the industrial revolution that turned work and home into two separate places. Men's superior strength made them more desirable workers, causing them to spend more time away from home supporting their families, leading to the archetype of the distant/stern father figure. |
Subsets and Splits
No community queries yet
The top public SQL queries from the community will appear here once available.