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Why do we call each other 'baby' when we love each other?
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When we think of a baby we think of something super cute which (especially if is ours) we unconditionally love. Which might be what you feel for your SO aswell.
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Because babies made that word, not use. The “ma”, “pa”, “ba” sounds are really easy for babies to make and pretty consistently one of the first noises they make consistently. So many languages have a formal word for mother and father, but almost all of them have an informal “-a -a” word as well, because babies say things that way.
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Could you use high powered lasers to burn/char paper instead of using ink?
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I used to work in a lab with a laser engraver and you could adjust the intensity down to cut or just burn a pattern onto paper. Laser engravers typically use CO2 lasers, which operate in the infrared so the laser is invisible. [Here is a laser engraver cutting paper](_URL_0_) and [here are pictures of etched paper](_URL_1_).
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It works via the photothermolysis of the pigment molecule - A short, intense burst of light is used to heat the pigment, causing it to disintergrate. Short bursts of light are used to prevent heat being transferred out of the pigment into the surrounding tissue, preventing burning/ scarring. You need different colours of light for different pigments of ink, corresponding to the maximum absorption frequency of each specific pigment. The light also has to be able to penetrate the skin to pigment depth, and be of high enough intensity to promote photothermolysis - otherwise pigemnt will be left behind. [Q switched lasers](_URL_0_) are commonly used to produce the required high energies and pulsed output.
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If sneezing helps relieve our noses, then why do we sneeze out of our mouths?
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Sneezing produces too much pressure to all go out the nose, the nasal passages are more narrow so the majority takes the path of least resistance and goes out the mouth. If you keep your mouth shut during a sneeze it will force it out of your nose only, but if your nose is blocked or the passages are too narrow for it to release as quickly as it's coming then you would cause damage to other structures, like blowing out your ear drum.
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Sneezes use the diaphram... and yes you can produce this own power consciously. To answer the question of why, it's because it helps force out whatever's caught in your nose.
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How did the first humans find out about natural death? Wouldn't "unknown disease" seem more likely as an explanation of why their friends never woke up?
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There is no such thing as natural death in the sense of direct causal connection to dying. You don't die of old age. You die of oxygen insufficiency when your lungs fail, cancer when your cells fail to reproduce correctly, your heart is too weak to pump enough blood etc. What we mean by natural causes of death in my understanding is "there was no external source in the form of a disease or trauma or any other affliction which directly affected death".
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Many Native Americans were killed by diseases brought to the continent by the Europeans. And, because diseases spread faster than colonists, many tribes were wiped out before the Europeans actually found them. I won't comment on the actual statistics, but these new diseases did kill *a lot* of Native Americans. There's a lot more information in [these previous questions on this topic](_URL_2_), on our Popular Questions page.
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"This isn’t the same stuff we had in the '60s and '70s." :: Has marijuana changed over the past 50 years, and if so, how?
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This will need citations, but I believe the main difference is not really that the amount of THC content has increased (hash always had a high percentage) but that the ratio of THC to CBD has changed, with there now being significantly less CBD. This is important because CBD has [shown promise as an anti-psychotic](_URL_0_) and the decreased amount of it in strains such as skunk could account for more people having problems. Having said that, the claim it was not the same stuff we had in the 70s is, as you say, one of the ways we manage the cognitive dissonance of wanting our children to do something different to what we did as children. It's also a standard prohibitionist argument used to counter the growing number of people who've had personal experience of cannabis and may need persuading to keep the law as it is.
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I wouldn't say that it's been a "sudden" change in sentiment. The legalization movement had been gaining traction for quite a while. Two big tipping points, however, are probably due to 1) the growing realization that the *War on Drugs* has been one colossal—and expensive—failure, and 2) the nuanced view the Medical establishment has taken on the use of marijuana for medicinal purposes. EDIT: Several big tipping points!
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If organism A is in the same species as B, and B is in the same species as C, is it always the case that A is in the same species as C?
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> If I understand correctly, we define 'species' by saying that if two organisms can mate and produce fertile offspring, then they are in the same species. If that's your definition, then the answer to your question is no. For example, see [ring species](_URL_1_), which is the situation where, for example, A can reproduce with B, B can reproduce with C, C can reproduce with D, but D can't reproduce with A. As mentioned in the article, the existence of such populations demonstrates that the ability to interbreed is not transitive. However, it's worth noting that this definition is not necessarily the only, or even the best, definition of a species. See [the species problem](_URL_0_).
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This is the sort of thing people who breed plants and animals do all the time. Similar arrangements where A breeds with B and B breeds with C but A doesn't breed with C are pretty common in nature; they are called [ring species](_URL_0_). Speciation is often less than complete and nonlinear.
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Do taller people die younger?
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[Yes.](_URL_0_) There are a couple of reasons for this. One is that tall people's hearts have to work harder to circulate blood, which will wear them out more over time. Another reason is that tall people have a larger number of cells than short people, which will lead to a statistically increased risk of cancer.
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Diet. People need to be eating well during their teenage years to hit the maximum potential height their genes will allow. The modern human eats more than humans in the past. Which is why we are taller, and well, fatter.
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How do they salt the inside of a peanut?
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They soak the peanuts in a brine solution and use pressure vats to pull the liquid through the shell. When the peanuts are dried before roasting the evaporating water leaves the salt behind. Source:_URL_0_
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They soak them in salt water. Then they dry them out and scrub the salt off the outer shell. The salt doesn't evaporate so it stays on the nut.
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Is alcoholism a disease?
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Addiction in almost any form is considered a disease in the health world. There are genetic predispositions to MOST addictive behaviours, and countless studies on the effect of nature vs. nurture _URL_0_ You may find that article somewhat helpful.
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Forgive me if I am wrong, but the addiction to alcohol isn't necessarily a definite process. As in, if you drink a lot of alcohol you just become addicted at a certain point. There are people who are more mentally stable who drink alcohol, have their fun, and then are completely fine until they want to drink again. Other people depend on how the alcohol makes them feel or how it affects their mood or outlook. These people develop the dependency or addiction not because of the amount of alcohol they drink, but because of their mental state and behavioral tendencies.
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Most say Columbus, some say Erik the Red, few say Piri Reis. Is it possible that Siberian Eskimo/Inuit/CorrectTerm discovered America first? People first crossed into the continent from Siberia, wouldnt Siberian inuit have been there firsr?
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Hi OP. One quick correction: Erik the Red is credited with founding the Norse settlement of Greenland, not usually included in "America" for sociopolitical if not geographic reasons. Instead it's his son Leif who is credited with leading expeditions to "America". Anyway, /u/TheAlaskan has written a few times about contact across the Bering Strait; here's a recent post * [Contact between Asia and North America before the Russians?](_URL_0_)
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hi! It seems that knowledge *did* spread, at least in Greenland, Iceland, Denmark, England, & Germany. It would be fantastic if an expert could comment on what Europeans thought of Vinland/Markland/Helluland in terms of significance; meanwhile, here's a round-up of related questions so you can catch up with the discussion so far: * [Is there any evidence that Christopher Columbus (and other 15th century explorers) knew of Lief Erickson's travels and the Viking settlements in the New World?](_URL_1_) * [Did word of the New World discovered by Leif Ericson ever get to the Western Europeans?](_URL_3_) * [Did the rest of Europe know about the Vikings' discovery of America?](_URL_2_) * [Are any of the pre-Columbus maps of America real?](_URL_4_) * [How did the Nordic countries react to the 1490-1500s New World discoveries?](_URL_0_) - i.e. versus what they already knew
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if raisins are dried grapes and wine is the liquid from grapes – could they be made simultaneously to prevent wastage?
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Not really. Only water is removed from grapes for raisins by evaporation. Wine needs crushed grapes (with the solids filtered out).
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Grapes are small enough that they don't usually rot before they turn into raisins. Also, the high concentration of sugar and low water content resist bacterial and fungal growth. The outside of the grape is made sure to be dry prior to drying. Besides that, other than dark raisins, most fruit like tomatoes and raisins that get "sun-dried" are treated with sulfites that extract oxygen, further resisting bacterial and fungal growth.
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Why are crayons (especially Crayola) only used by small children?
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Crayons are good for kids because they are bright, safe to eat, hard to poke your eye out with, and pretty cheap. Colored pencils offer better control and a neater end product, but cost more, and are more dangerous.
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Crayons don't lend themselves to fine details. They also don't blend together very well. These two factors combine with the fact that they're generally cheap & don't age well to limit their usefulness in "serious" art, leaving you to mostly make "simplistic" and "childlike" drawings. Closely related to crayons, however, are [pastels](_URL_0_). They're basically crayons without all the wax in them that are fairly widely used by "serious" artists. They're blendable & allow you to get finer details. You can get "chalky" ones and oil pastels - oil pastels are really close to using crayons. Of course, these days, if you've got your mind set on it, you can use pretty much any damned thing you want as an artistic medium. If you've got talent, you can get away with it.
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How come hitting my tv remote against my hand makes it work again when the batteries are going?
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When batteries get older, they start to 'dry up'. Inside the batteries in your remote there's a substance like a gel (called the battery acid) that's separated by a non-conductive barrier. Part of the gel holds the charge to be used, the other part receives the charge after its used. When a battery gets old this gel can form crystals that make it hard for a weak charge to go through. Jarring the battery by hitting the remote against your hand breaks up and moves these crystals around, allowing the weak charge to flow again. Really, you should be replacing your batteries at this point. Hitting your remote is just going to break it.
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Towards the end of a batteries life corrosion can start to build up, reducing the effectiveness of the electrical pulses sent through the battery to the remote. Smacking it once or twice can often shift the batteries a bit or ‘dust’ off this corrosion enough to allow them to work properly.
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Did the U.S. government ever own any slaves, or were all slaves in the U.S. privately owned?
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Slaves helped build the White House and the federal Capitol building. Though it appears it was by paying the owners as independent contractors rather than direct ownership by the government.
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I actually answered almost this exact same question a year ago . You can check out [my answer here](_URL_0_). But before reading it, I’d like to preface that your question makes the assumption that the government would have to own slaves in order for them to work on government buildings. This is incorrect. As in the case of the White House, which did have enslaved workers, they were not owned by the government, but rather owned by the folks who were hired to build the buildings. The White House was not the only building built by slaves in Washington D.C. The Capital building was partially built by slaves (it’s construction took place prior to, during, and after emancipation). It is likely that other buildings were built by enslaved people since both Virginia and Maryland that surround it (where companies and workers would have been hired from) were deep slave territories. I hope this helps. Please feel free to ask follow ups if I didn’t fully answer your question.
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What was the name of the famous battle in the Gulf war where 100 Abrams tanks took on 400 Iraqi ones
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The Battle of 73 Easting. Wikipedia: _URL_2_ The Coalition commander the armored troop, Captain (now Major General) HR McMaster, wrote this report on the battle: _URL_4_ Maps: _URL_3_ This book was written by a veteran of the battle: _URL_0_ This short blog post was written by a veteran of the battle. Blog comments are instructive but of course not definitive: _URL_1_
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Methods that occasionally worked: - Using tanks - Preceding an attack with an extremely heavy artillery bombardment, destroying much of the enemy position
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Cheap and expensive toothpaste - is there really a difference
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Denist here. I don't are what toothpaste someone uses as long as it has fluoride in it. But watch out for the abrasive toothpastes, you will lose layers of enamel over time and that is what make your teeth strong and white!
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Toothpaste doesn't really kill bacteria. It's there to *take away the stuff that the bad bacteria eat*. Basically, the bacteria that cause cavities take sugar and turn it into acid, which eats through the enamel on your teeth. Toothpaste helps clean the sugar away, and may shift some bacteria out, but the main advantage of toothpaste over just brushing is fluoride. This helps strengthen your enamel.
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Why did the government let Lehman Brothers fail but help all other companies during the Financisl crisis of 2008?
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The federal government originally tried to take a principled stand: if you make bad business decisions, and they come back to bite you, you deserve to go out of business. Lehman Brothers collapsed under that set of circumstances, and the government just let it fail. Once Lehman Brothers failed, though, things got worse. The fact that the US government let a major financial institution go out of business was a wake-up call to the others, and they all started trying to cover their asses, which resulted in nobody being willing to loan money to anybody else. That caused a lot of extra strain on the financial sector, which threatened to cause a whole load of additional failures, so the US government at that point went for a more pragmatic approach and bailed out a bunch of businesses so that their collapse wouldn't bring down the economy as a whole.
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In the system that existed before the collapse banks were, strictly speaking, not entirely solvent. Day-to-day, they may have run multimillion dollar losses without the money to actually pay their bills. Other days, they would run multimillion dollar gains. In order to prevent each other from constantly going out of business, banks set up a system of loans where banks who had gains on the day would loan some of that to banks which did not to cover their losses, on the expectation that the money would be repaid and that those banks would return the favor in the future. On the day Lehman Brothers failed, they didn't get one of those loans. When they failed, everyone who had money with them lost it, including other banks which had previously loaned them their good day gains. Those banks failed as well, and then a massive cascade started with hundreds of banks failing one after the other as they could no longer get loans to cover daily losses.
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Do all animal eyes create a inverted image that the brain flips over or do some animals have eyes the create an upright image?
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Here is my previous answer to similar questions: > Although it is true that the image on your retina is inverted (up-down and left-right), it is only inverted [relative] to an outside observer. That is, if I am looking at your eyeball, the bottom part is getting light from the upper part of the world (relative to my being upright). > But your brain is not an observer. It does not have an extra set of eyes looking at your retinas and comparing that to the world. There is only one image (what's on your retina) that the brain has access to and there is nothing for it to be inverted relative to. There is no "flipping" that the brain has to do.
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Most "prey" animals have their eyes on the sides of their heads, and therefore already have almost 360 degree vision. For example, here's a [horse's field of vision](_URL_1_). And [here's a rabbit's](_URL_0_).
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why are car wheels so much smaller than bicycle wheels?
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While you are correct that all else being equal, bigger wheels are harder to push but make the vehicle go faster, most vehicles use gearing to have any overall ratio they want (the ratio between the speed of whatever the power source is and the wheels), making that issue obsolete. The main reason why cars generally use smaller wheels is because big wheels take up space that can otherwise be used for passengers or cargo. The disadvantage of small wheels is that they offer a rougher ride, but cars have sophisticated suspension to deal with this. Bicycles have very simple suspension, and sometimes none at all.
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Bike wheels rotate much more slowly than F1 cars. There are thin to cut down on friction, weight and air resistance. F1 cars need traction. The bigger wheels give them far more grip on the road and allow them to drive very fast with far less wheel spin. This is my understanding, could be wrong.
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How do babies automatically associate frowning with sadness/smiling with happiness?
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There are inherent connections in the brain between facial expressions and emotional states. When we are happy, we automatically will feel like smiling. Similarly, when we look at someone who is smiling, we tend to feel more happy, as a result of connections in our brains. This is probably strengthened as we grow up--when your baby smiles, and you smile back, it learns to further associate smiling with good feelings.
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For babies it has a practical purpose. Without realizing it, you're over stressing and emphasing important sylables to help the baby pick up on them. You're also teaching it to relate tonal changes to non-verbal social cues. By over emphasing the "I'm happy" tone while having a good time socially interacting with it.
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What made earlier game consoles easier to emulate and what makes newer consoles so difficult to emulate?
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Emulators are software emulating hardware. The more powerful the hardware that you are trying to emulate is, the more complex and powerful the software and machine you are running it on has to be. SNES is very old and fairly simple, and so doesn't require much power to emulate successfully.
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Consoles are restricted hardware. The console manufacturers control what runs on a console, and therefore charge a licensing fee to the game developers to allow their software to run on the hardware. This is typically in the form of a fee per copy of the game made (this is the reason that new console games are more expensive than new PC games). Regardless of how old a game is, the developer will still have to pay the same fee per copy to the console manufacturer, so this limits how cheap the games can be made. On the other hand, PCs can run whatever software they like so retailers/developers have more freedom in pricing.
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In late Republican Rome aristocratic generals often raised legions out of their own pocket, without the Senate's approval. How did individuals control how much money relative to the state? What was the scale of that wealth relative to the economy of Rome?
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What generals are you thinking of that are raising legions out of their own pockets without senatorial authority? Catiline and Manlius did so, but their troops were in open rebellion and were likely not paid and provided for normally--Catiline could not mint coins, after all. Generals during the civil war? I think it's pretty silly to talk of senatorial approval for *imperium* during the civil war. Even then, the Republicans before Philippi were unable or unwilling to pay for their army and resorted to collecting funds, often by duress, from eastern cities. The Pompeians resorted to a similar tactic (much of their wealth, like that of the Republicans, would have been locked away in Italy and confiscated by Caesar), confiscating money left behind in the east belonging to, among others, Cicero. Who are you thinking of exactly who's raising self-funded armies without senatorial approval? Sertorius? Any example I think of is unusual, an individual in revolt or in open civil war.
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As a follow up question, where would they store their money. Did they have banks? If yes, who could deposit money there, like anyone or only rich people? If there were no banks did they have like a treasury room where they would store all their dough? Im sorry if these questions are super basic but basically, could you explain me how money management went for rich people (not necesarry Roman citizens, but I guess all rich people in Rome were citizens)? Thanks
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How come we can see things so vividly in our dreams but can't create such vivid images in our imaginations when we're awake?
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Because our dreams are *not* that vivid. They leave out tons of information, and when we wake and try to recall the dream, our brain fills in gaps with information that wasn't even there during the real dream.
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You're not "seeing" them. Your human brain took a mental picture of the objects and people that you saw when you were awake, and in REM sleep it somewhat randomly accesses these images and replays them as part of some crazy script that involves nefarious penguins, a bubble-wand, and Great Aunt Hilda's magic underpants. Fully blind people from birth don't see anything when they dream. Their brain never got those images like people with normal vision did. People that lost their sight have some images from before that occurred, and the brain uses those memories, but the frequency of that reduces the longer they're blind.
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Why does a change in colour of an image/object from blue to red, make it appear as though the object expands, and vice-versa?
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Where are you seeing this shift? On a computer monitor remember the red green and blue portions of each pixel are in slightly different places. If you change a medium sized square on a computer screen from red to blue you will observe a shift in position but not in size.
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Blue glass looks blue because it filters out all colors that aren't blue. Stop light doesn't have any blue, only red, and the red gets filtered out because it isn't blue which leaves nothing at all.
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How did the architects of the great pyramid of giza get such precise measurements or why are there so many coincidences?
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There's a mixture of plans and coincidences. The Egyptians were skilled mathematicians and astrologers who had been developing for some time theories about the motions of the night sky. The first pyramid was only a pyramid, but for the placement of each subsequent one the pharaoh's advisors attempted to put in as much occult correspondence as they could. They managed quite a bit, but a lot of it was still a coincidence. The land masses thing, for example, only works if you consider Europe and Asia separate land masses, which the Egyptians didn't. But a lot of it, particularly the placement of stars at different times of year, was intentional, much as it was with Stonehenge.
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Not science disclaimer: This is not science. Land is sold by the acre which is surface area. The whole point behind very tall buildings like the Burj Khalifa is to maximize *that* patch of planet that it is built upon. When the design constraints begin at the very bottom, the only choice is to go up. Pyramids have very large footprints for buildings of their size. The Great Pyramids of Giza had no footprint constraints when design began. There is no reason that a pyramid would not be a good design for a very tall building. It just won't happen for a while because very tall buildings are only in demand in tightly packed metropolises. TL;DR: Location. Location. Location.
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How do we judge height on planets and moons without a Sea Level, where do we start measuring from?
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Sea level is only relevant on a planet with an atmosphere and ocean because it tells you the likely atmospheric pressure at your location. Water has the tendency to fill in all the lowest points which makes this measurement work. Mars has an atmosphere and no ocean, this means that there is really only an average surface level and no sea level. Scientists call this an [Equipotential surface](_URL_0_). On earth this surface is known as a [Geoid](_URL_1_). However, since geo means "of relating to earth" the name for this surface on mars is an areoid. Nasa uses the term in their analysis of the data from the mars global surveyor _URL_2_
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Put a stick in the ground. As the day goes by the sun rises and sets. Now watch the shadows the stick casts. As the day goes by the shadows change. If you know the angle the sun is at , you can use that to calculate how tall the stick is from the changes in the shadow. Galileo did that with the mountains. As the month goes on the angle the sun is shining on the moon changes. Galileo knew that angle. He then tracked how the shadows of the mountains and craters changed and calculated their relative height.
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If a girl's body is "ready" to give birth once they start getting their period, why is it considered dangerous for people to do so at a young age?
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It's 'ready' in that it is biologically possible. Pregnancy/Birth can be dangerous or even deadly even for an adult woman. Being young can increase the risk of a variety of complications for both the child and parent.
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it has ot do with efifciency and the body not knowing any better since its acting on a blind cycle expecting fertilization to happen. if no fertilization occured, there's no point keeping that tissue(and the egg) aronud until the next cycle, plus that tissue is only there due to hormonal changes meant ot facilitate an embryo's introduction, hormone levels will drops if no pregnacy is in place. ys it looks unecessary, but it would bej ust as pointless to have a permanenent " ready" uterus, considering the process gestation and childbirth involves
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Why does shampoo/conditioner squeezed from a bottle pour down straight, but then curl when it hits a surface?
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This is called "Liquid Rope Coiling". Essentially, the fluid is so viscous that it's able to push against the flowing 'rope' of fluid to move it out of the way, where it naturally (usually) falls into a coil of the roped fluid. If you were to lower an actual rope or string onto a surface, chances are you'd observe a similar effect. This only happens to very thick and viscous fluids, like honey, molasses, or shampoo.
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Glue often has a solvent mixed in to stop the glue from curing when it's in the bottle. When the glue leaves the bottle, this solvent evaporates allowing the glue to set. While some of the solvent does evaporate inside of the bottle, there simply isn't enough air in the bottle to allow enough of the solvent to evaporate.
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Do animals experience pain during metamorphosis?
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This is a good question with poor answers. Pain is very difficult to detect in non-human animals. The more expressive ones tend to be social and closely related to us so its easier to interpret pain in dogs and primates and dolphins. But when it comes to frogs and bugs it is very hard. These animals do not express emotions the way we do. Metamorphosis does sound painful, but I am not quite sure how we can answer this question.
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Animals don't experience pain differently than humans. You are just familiar with wimpy humans. Here is an example of a different type: _URL_0_
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Why are hospitals allowed to sell blood to patients that is taken from donors?
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Storing and testing blood costs money, so the blood bank charges the hospital and the hospital charges the patient for that plus the costs of administering it (and a bit extra). SOMETIMES blood doners get paid money (if blood is extremely scarce), but that's rare -- normally they donate the blood (which didn't cost them anything) for free because they know it will help someone.
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It's because donated blood is used directly on patients and therefore the kind of people you attract when you pay for blood are more likely to be ones that engage in at risk behaviors. Plasma on the other hand is often not used whole and more often used for research, not human application, so the risk of contamination by blood borne pathogens is worth it.
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Is it (theoretically) possible to create a spacecraft with artificial gravity that does not rely on the craft itself spinning to generate it?
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If you have 6MWs of power to spare and create a 20 tesla megnatic fied (400,000x earth's natural field) then you can generate 'gravity' of about 1g over the body of a mouse or other small creatures (insects). In theory a much stronger field could do the same to a person and placed in the roof of a ship and acting down could provide something close to artificial gravity. However the fields required are so strong safety could well be compromised and the other problem is anything magnetic anywhere in the area would become majorly hazardous. - _URL_1_ - _URL_0_ Other than that you've only got three _real_ ways of producing the effect; spinning, acceleration, and using ultra dense masses to create natural gravity. Sorry I don't know enough about it to even think about exotic matter or manipulating Higgs fields.
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Currently only simulated gravity via a spinning object with the living quarters situated along the inside of the bulkhead. As the object spins, centripetal force would pull the objects inside towards the hull. Slightly more sci-fi, you could plate the floors of your craft with some sort of super-dense material, like neutronium or tiny black holes. You would not need much material to create a gravitational pull. But as far as Star Wars and Star Trek technology, where every ship just magically has a "down" and they never really explain why, no, that is not possible.
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Can someone extract information from your cellphone pictures?
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This is how that nut-job [John McAfee](_URL_0_) was captured. > Oddly, Vice directly contributed to McAfee’s capture by revealing his location in the metadata of a photo it published. This was deeply stupid. People have been pointing out the dangers of inadvertently leaving GPS tags in cellphone pictures for years and years. Vice is the same publication that regularly drops in on revolutions and all manner of criminals. They should have known better.
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The phone is easy to trace, the person using the phone is not. There is nothing magical about the phones specifically, it's how they are used. Burner phones are bought by companies in huge batches, and don't require any plan or contract to use. So there's not a great way to know who is using that particular phone. They are also cheap enough to throw away and "burn" every so often to keep a pattern of use from being determined. Even if you could narrow down the phone was purchased at Walmart on a certain date, there wouldn't be a great way to know which one of the hundred that were sold that day is your suspect.
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How long can a plant survive in space?
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Depends on the environment. Plants can grow in microgravity with an artificial atmosphere, but if you're just talking about throwing a naked plant into space, the extreme temperatures would start rupturing cells immediately (areas in the sun would be very hot, and areas in shade would be well below freezing). Between these two extreme temperatures and the very low pressure, which would also accelerate the rate at which volatiles boiled off, the plant would start to die as soon as it was exposed to this type of environment. How long is likely a function of the species and plant size.
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As far as I learned in my college botany and biology lectures, most plants depend solely on resources and environment for their longevity. If environment is favorabel, and all nutrients are available, plant can technically live forever. That is why plants are good for cell cultures.
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How can neutron stars have a magnetic field if neutrons are neutral?
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How can atoms have a magnetic field if atoms are neutral? Neutrons do actually have a magnetic field. However, the magnetic fields of neutron stars mostly comes from magnetic dynamos. Neutron stars are composed of more than just neutrons, there are also electrons, protons, and even whole atoms (in a thin surface crust). They are outnumbered by the neutrons, but it doesn't take a lot of mobile charges to enable strong magnetic fields to develop.
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Despite their name, neutron stars not entirely composed of neutrons. The outer layer is conductive and consists mostly of protons and electrons. The primary reason for the very high strength of the magnetic field is most likely conservation of angular momentum. As the star collapses to the neutron star state, the angular momentum is conserved. So as the star gets smaller, the angular velocity must increase, and charged particles rotating very fast creates a very strong magnetic field. [This paper](_URL_0_) discusses several hypotheses for the origin of the magnetic field.
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the republican party
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The modern GOP (it's MUCH different than from what it once was - Lincoln was a Republican, and southern slave owners were Democrats) is conservative, both fiscally (money wise) and socially. They believe in religious rights, that religion should be a part of government and daily life (prayer in school and things like that), believe that marriage is between a man and a women. On economics, they believe in a free market (capitalism), do not like entitlement programs such as welfare, are pro-large military, and think over all that government should be small.
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The Republicans chose their nominee, Mitt Romney. Mitt Romney will now officially be on the ballot in the general election this November. This is officially the end of the primary process. Throughout the primary process, each Republican candidate was gathering delegates in each state by winning the various primaries and caucuses. The Republicans also wrote out their platform. The platform is the party's official stance on a bunch of issues facing the country. And the Republicans set in place the rules for the primary process in 2016, which is the next year the US has a presidential election.
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why can cancer cells keep on dividing?
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> Doesnt a normal cell die and stop dividing when the telomeres run out Not exactly. Fraying of telomeres can result in the cells stopping performing their function properly but that doesn't really stop cancer from being cancer; it could just be the difference between a tumor that creates a hormone or doesn't. Part of what makes cancer what it is includes the normal functions which would tend to limit the growth of cells being disabled, which includes normal cellular senescence. Some cancers then are biologically immortal. An example is a sample of ovarian cancer which has been grown in labs for test samples for a very long time (and without the express permission of the donor which is its own issue). Even after the donor died from old age the samples continue on.
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This is a ELI5 explanation, it's more technical, but contains the good bits. Radiation damages your DNA (anything's DNA, not just humans). Most of the time, this just kills the cell. If it happens while the cells are dividing, this is really bad, because your new cells will be damaged and always produce damaged cells. Human cells are dividing all the time. Each individual cell divides about every 30 days, but it's not like it all happens at once, each cell can be on a different schedule. Cockroaches and flour beetles (Mythbusters did a test and flour beetles handled radiation better than cockroaches) don't have frequent cell division like humans do, they tend to happen all at once for them, so they're less susceptible to radiation damage.
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what does "undetectable" mean for an HIV positive person?
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it means their viral load is so low it cannot be detected by current tests. They are still HIV positive, but the disease is in check, and their risk of infecting someone else is significantly lower, but never eliminated.
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HIV Experts: Can anyone explain what this question means in layman's terms? I'd love to be able to follow this post (I check askscience a lot to learn a thing or two) but I have know idea what ymstp's post actually means, much less what the answer might be.
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What did some of the bygone civilizations call their religions/belief systems? (ancient Greek, Roman, Norse, Aztec, etc.)
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Early polytheists didn't really have a concept of religion as something separate from general culture/tradition. Even Hinduism is a pretty modern name, introduced to distinguish followers of traditional Indian religion from Muslims and Christians. Polytheists wouldn't refer to religion as "the truth" either, since religion weren't really a fixed statement about the world. It was more a set of traditions and rituals and gods to worship. That other people had different traditions and worshiped different gods, did not mean that they were "wrong". Even inside a polytheistic pantheon, different Gods could be rivals and have different objectives, so a polytheistic religion did not constitute a singular "truth". Judaism is one of the first religions to state that other peoples gods are not just wrong to worship but *fake*, and only their own God is the only *true* God.
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I want to be clear that a lot of those similarities are superficial. The Spanish definitely used those similarities to help with conversion, but the two religions certainly had more that was different between them than they did in common. You could also probably find similarities between the Aztec religion and several religions from Asia. I'm not sure about Buddhism specifically, but Mesoamericans did share the idea of a "life energy" permeating all things. But I'm not really sure how deep those religious similarities are. If you picked any two religions on the planet, they would probably have a handful of elements or motifs in common. But that's likely just a function of the fact that humans tend to come up with similar ideas. It doesn't imply a connection.
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How does emergency contraception (morning after pill) containing levonorgestrel work? Pre-fertilization or post-fertilization MOA?
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Both. Pre-fertilisation: it can prevent the egg from being release or it being fertilised (by making it harder for sperm to enter the womb). Post fertilisation: it's effectively an abortive, which works by preventing the fertilised egg from embedding in the wall of the uterus. The divergence is probably down to the fact that there is more than one morning after drug.
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different physiology. The female pill basically fools the body into thinking is pregnant already so that an egg will not implant in the uterus. There is no equivalent in men who produce sperm regularly. Nobody has figured out a pill to stop that production without some nasty side-effects. Companies are working on it because the one that gets it is going to make billions
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Why don't most of us fall out of bed more often?
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That's why men get erections in their sleep - it keeps them from rolling out of bed.
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Stress. Stress is keeping you up awake at night, until you become so sleep deprived your body forces you to be knocked out.
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Why do Acids Melt Stuff?
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Lets be clear on terms: melting describes a solid going to a liquid as a phase change (thats not whats happening here). What is typically happening when acids "melt" something is they are breaking bonds / aiding oxidation. Acids are lone pair acceptors and faciliate the oxidation of typically carbon in polymers. When that happens the target appears to melt because its actually breaking down. Its not a phase change its a chemical reaction.
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By reacting with them. The stronger an acid, the more abundant the Hydrogen atoms. The more abundant the Hydrogen atoms, the more badly the acid wants to "give away" those Hydrogen atoms. The acid gives these atoms away by reacting with whatever it comes into contact with, making it appear that it's burning through or melting the material.
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How efficient is the bouncing of kangaroos compared to other forms of bipedal movement?
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I can't speak to bipedal bouncing specifically, but tetra-pedal bouncing (called pronking or stotting) is highly inefficient. It's because you build up all this momentum and then land with all 4 feet at once and you experience deceleration. There are hypotheses that perhaps pronking is used to clear low brush, to see incoming predators more easily, or as an "advertising" tool for mates. I'm sure it's easy to picture a gazelle doing this, but here's a [video for the curious.](_URL_2_)
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Chimp walking and running are both fairly inefficient energetically (relative to quadrapeds), whereas as human bipedal walking is much more efficient than chimp walking and human walking is about 30% more efficient than human running. This is strongly suggestive that human bipedalism is an adapation for efficient walking. Interestingly human and chimp running speeds are about equal. Here's a good page from google books _URL_1_; And here's a summary of some recent research on human locamotion efficiency in the Smithsonian Mag. _URL_0_
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If the purpose of fruit is to get animals to eat it and spread the seeds... Why are some berries poisonous?
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For some plants, only the *unripe* fruit is poisonous. For those plants, it's to keep animals from eating the fruit until the seeds are mature enough.
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Fruit isn't *meant to be eaten by animals*. Plants reproduce in *many different ways*, only one of which is by producing seeds inside of tasty fruits for animals to eat, walk off, and then shit out the seeds elsewhere. *Some* fruit is tasty and meant to be eaten, whereas some fruit is poisonous and used to ward off animals so that they can't eat the leaves or roots of the plant, which allows it to survive long enough to produce viable seeds. When the seed is inside the fruit, it prevents animals from eating the fruit before the seed is ready to fall off naturally.
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People say "chemotherapy doesn't cure cancer...it's just used because doctors profit from it." Is this true? Can someone ELI5?
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Whoever said that is a paranoid nut. Treating cancer is difficult. Chemotherapy uses medicines that are taken orally or injected, reason being that way they will travel through the bloodstream and reach the ENTIRE body, killing any potential tumors the doctors may have missed on xrays or the like. The problem is since it affects *the whole body*, and is some seriously powerful stuff, it will definitely make the patient feel very ill, and requires close monitoring to prevent doing more damage than the tumor would. This process *does* kill tumors, but it's incredibly challenging to kill cancer cells while leaving healthy cells alone.
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But it does. Why do you think many patients' hair falls out because of chemotherapy? Scientists try very hard to make chemotherapy that targets only the cancer cells (but explaining how exactly they do that is complicated beyond my own knowledge, has to do with cell biology and is way beyond Explain-like-I'm-five" material.)
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Why can't a normal plane reach space? By flying at the same angle as takeoff longer, why can't it reach orbit?
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Because planes require air to support their wings to gain altitude. Every plane has a 'ceiling' where there isn't enough atmosphere to provide lift. Orbit, in space, has no air. So, you need rocket engines to get to orbit
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Rockets are basically controlled bombs that only explode in one direction. sometimes the materials fail and it explodes in all directions. We cant make plane like rockets, because planes dont work in space. Planes work by creating a pressure difference around wings caused by fast moving air over the wings. As you climb through the atmosphere, it gets thinner and you will generate less lift. There is a maximum height that conventional aircraft can reach.
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Why some foods at fast food restaurants are discontinued, even when they are insanely popular.
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You're talking about the McRib aren't you? Having a new product (or a recurring one) gives a company something to advertise about. McDonald's spends an insane amount on advertising but there are only so many Big Mac ads they can run. So they bring back the McRib, make a huge splash, get Reddit worked into a frenzy, and then discontinue it for a while. Then when it comes back they can make a huge deal of it. In addition, the price of the food may go up and make it not as profitable. If the price of pork goes up then McRibs may be priced out of the "sweet spot" their marketing has determined is best, so they cancel it for a while until they can get a good deal again. In double addition, just because something *seems* popular doesn't mean it is actually profitable.
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They are not commonly eaten and so they are not commonly raised for food. Their supplies are much smaller and that means the prices are higher.
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Why do dogs shake their legs when being scratched in the right spot?
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It's a completely involuntary reflex called the scratch reflex. It's so reliable that vets can use it to see if a dog has nerve damage.
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It could be like a cat's. When you scratch a cat on the lower stomach and their hind legs go crazy scratching you, they don't do it on purpose. They actually do it to themselves sometimes. It's triggered because in the wild, when they would get pinned by the animal they're fighting, their hind legs would attack the vulnerable stomach of the other animal that is on top of them.
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During gene expression, how does a cell "choose" which chromosome to express?
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They usually express both. The exception to this in humans is the x-chromosome. The cell chooses which one to activate early in development and the non-activated one shrivels up and becomes a [barr body (link to the process)](_URL_0_). There are some interesting cases where specific copies of a gene - maternal or paternal - are silenced consistently. Essentially the copies that come from one parent are tagged with methyl groups - these prevent DNA copying enzymes from binding, ensuring only one parent's genetic contribution (at one particular locus) is expressed. [Some info on epigenetics](_URL_1_) which goes into more detail on the embryonic and neonatal implications.
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Let's use humans as an example. Most of our cells have two complete sets of 23 chromosomes (46 in total). One of those in each set is a sex chromosome, that exists in X and Y versions. In females, both sex chromosomes are the X version, in males there is one X and one Y. Sperm and egg cells, however, have only a single set of 23 chromosomes. Each one is more or less randomly chosen from one or the other of the two complete sets we have. Since females have two X chromosomes, all egg cells contain an X chromosome. But since males have an X and a Y chromosome, sperm cells have either an X or a Y, with a 50:50 mix. So when sperm and egg combine to give two complete sets of chromosomes again, if the sperm cell contains an X, the offspring will have two X's and will be female. If the sperm cell contains a Y, the offspring will have an X and a Y and will be male. tl'dr: sperm cells randomly get assigned an X or Y chromosome, and that ultimately determines the sex of the offspring.
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How does Paypal work? Why do so many people use it? How come a lot of people on Reddit hate it?
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Someone correct me if I'm wrong, but I believe PayPal is basically just a service that accesses your bank account and allows you to make monetary exchanges easily and securely. I like PayPal because all you have to do is enter your username and password to pay for something. No need to type out all of your credit card information. And it's set up in such a way that your information can't be stolen since you log in through the PayPal website to pay for things.
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I believe it would have something to do with the security measures of PayPal and how easy it is from a sellers perspective. Most people on eBay will have a PayPal account, and so sellers find it easier to just have one method of receiving money rather than messing around with credit and debit cards as well as money orders and that sort of thing Especially for foreign sellers, PayPal is just easier
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Why do restaurants/fast food chains even have secret menus?
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That's exactly why. They don't make enough money to make the menu, but if they have the ingredients they might as well sell you some food.
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Not to discourage further discussion, but /u/dhmontgommery had a [previous answer](_URL_0_) on the history of restaurants. The first "restaurants" only offered a set meal at a set time, so no menu was required.
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What does E= mc^2 really mean?
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a way this is used is when some kinds of elements which are radioactive like some kinds of uranium releases radiation. This radiation comes in 3 forms. Well only talk about one form that is gamma radiation. When uranium radiates gamma radiation, this gamma radiation has no mass but it was observed that the uranium sample kept decreasing in mass. This was observed and it was concluded that energy of the gamma radiation radiated was proportional to the mass lost from the uranium. So some simple calculations were done and e=mc^2 where e is energy, m is mass and c is the speed of light.
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In this case c is just a factor of conversion between units of distance and units of time. In natural units we can set c=1 (as is commonly done in relativity), and that makes the equation E=m (that equation is indeed valid for any system in its center-of-momentum frame). If you define Q=Ec^2 , and it holds for all physical systems, then the quantity Q *is* the energy, just expressed in different units. This is not fundamentally different from (for example) the conversion between heat measured in calories and energy measured in Joules.
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What is a "sigh," exactly, and why do we do it when we're sad or exasperated? Does every culture sigh?
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I don't think it's cultural or even human for that matter. I've heard my dog sigh when he's frustrated
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When you exhale, you release some tension from the body. A sigh of relief is simply exaggerating that– you let out a good exhale now that you can relax for a bit.
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What is that static-y buzzing feeling I get whenever I wake up from a nightmare?
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Heck yeah I get that static-in-my-brain feeling too (sometimes it just feels like my brain got squeezed in a vice), and I dunno why I'm so excited to see someone else explaining *exactly* what it's like when I force myself awake from a lucid dream, but yeah. I dunno where I was going with that. I'd like to know why it happens too though.
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Your alarm had probably already been going off for a short while. It's like the kicker in Inception. Noises from the real world can seep into your dream world and then your brain just uses that sound for whatever it feels like. I have the same thing sometimes. Like my alarm is the sound of a bomb about to explode or a birdsong.
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Since the Power-ball lottery is so high right now it made me wonder; does the number of people buying tickets affect my probability of winning?
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No. The probability of picking 5 random numbers + 1 random powerball number correctly is entirely independent of the number of players, which should be 1 chance in 175,223,510. What does change is the probability that you will have to share your winnings should you actually win - as more people play, the likelihood that two people share the same set of numbers increases.
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Powerball has about 175 million possible combinations. So, if you bought 175 million tickets you would be guaranteed that one of them would win. When the jackpot gets this high you are going to have a lot of people buying tickets. They may not sell 175 million this week, but they will probably sell at least 100 million. So, there's a pretty good chance that someone will win, but it's not guaranteed. It has been since Oct. 6th that anyone has won Powerball. They have two drawings a week. So, that means there have been something like 16 drawings in a row where no one has won.
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Why do many Asian countries (China, Russia, North Korea, etc) have massive military parades with servicepeople carrying weapons, while many other military powers do not (US, UK, France, Canada, etc)
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It's mostly down to posturing. Basically it's a way of them saying "Look at my armed forces. You might not want to pick a fight with me". Also the majority of the countries that do this kind of thing tend to have a reason for showing them off as a show of force because they are insecure. For example North Korea is paranoid that the USA wants to destroy it, so it makes a big deal of showing off it's armed forces. China has issues with territorial claims, etc, etc. Countries like the USA, the UK and so on don't really need to do this because they don't have these insecurities. The USA simply doesn't bother because it's doubtful anyone is in any doubt as to their military capacity.
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Because they need to call them something clearly identifiable that leaves room for future itterations. The US does something similar with its equipment designations. * M-1 Tank * M-16 assault rifle * M-4 carbine * M-92 handgun * M-203 grenade launcher * M-249 Squad Automatic Weapon
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How and why do antenna extension cords work?
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Cables that hook up antennas are coaxial cables. They consist of a central conductor surrounded by a dielectric and then a cylindrical, grounded conductor surrounding that. All signals travel down the central conductor as current or in the dielectric as an electromagnetic wave in a waveguide like fashion. As you go to higher frequencies, it begins to act more and more like a wave guide. The outside grounded conductor (ideally) confines all electric and magnetic fields inside, preventing it from radiating. The outside conductor also (ideally) shields it from all external electric and magnetic fields, preventing it from recieving any signals. As such, it does not act as an extension of the antenna.
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Antennas work by creating an electric field. They have poles like a magnet, the stronger the field the stronger the signal. The shape of antenna can direct this field in a preticular direction. The size of an efficient antenna is proportional to the wavelength. Field strength is determined by voltage created across the antenna. This can be increased in some cases by tuning the antenna so it rings like a bell at the output frequency.
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Did the Roman Army have strange and bizarre rules similar to the US military of today?
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A potential example of a "pointless" routine/tradition in the Roman legions that filled a similar role to shining boots (and other gruntwork) was the building of castra. Castra were on-the-move forts that a legion could build each day and then destroy in the morning before they marched on. The forts obviously provided nighttime protection, and this was their primary use. But they may have also played a role in keeping soldiers busy and out of trouble. Some have asserted that the building of fortifications by the Roman legions was significantly (or in some cases, primarily) motivated by generals just wanting to keep their soldiers busy. Source: Rome and the Sword by Simon James.
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It's mentioned in Vegetius' *De Re Militari.* The book is a military manual written in the late 4th century outlining how Vegetius thinks the Roman army should reform itself to be more like the early Empire's military. Vegetius says that the army of his day did not fortify camps, and should re-adopt the practice since it has led to several armies being taken by surprise at night. Vegetius makes the case that this is another product of the neglect of the previous emperors in maintaining the military, and the barbarization of the army. This was also helped along by the fact that the borders had stabilized and more permanent fortifications were built on them, and the armies became much less mobile, thus leading to a decrease in the practice.
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Why can't an orbiting spacecraft match the speed of the Earth and decend into the atmosphere to reduce the friction of reentry?
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Because friction slows you down for free, but reversing a low-earth orbit requires an absurd amount of fuel. It takes a gigantic rocket to lift a few hundred pounds into orbit. In order to slow the spacecraft down you'd need to carry the rockets and fuel required to do so into space, which would require a much, much larger rocket.
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An important point in this discussion is that it is not friction that heats spacecraft on re-entry to such incredible temperatures. Whilst frictional heating does play a part, more important is the compression of the air which creates a superheated shockwave in front of the craft, this shockwave transfers it's heat to the craft casuing the 1000+C temperatures. The reason why this does not happen with aircraft is a matter of speed, spacecraft re-enter the atmosphere at many times faster than even the fastest spacecraft, also, where aircraft are designed to reduce drag spacecraft are designed and flown to maximise drag as they need as much drag as possible in order to decelerate.
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If you're nearsighted, and you're directly in front of a mirror, why is the reflection of a far away object still blurry? Since the reflection is right there, shouldn't it be clear since it's "close" to you?
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The mirror also preserves the direction the light is coming from and not only the image. So the items in the mirror are in true 3D. The issue of being nearsighted is that you are not able to make the light hitting the left side and right side of your eye lens hit on the same spot on the retina if the light hits at very similar angles. Since the mirror preserves the angle the light comes at the light hitting the different part of your eye lens is coming at an angle similar to how it would if it were far away.
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The image of the chair sits 10 feet behind the mirror (since the chair itself is 10 feet in front of the mirror). So it will be like looking at something that is 15 feet away. Here's something you can try: Put some drops of water on a mirror. If you let your eyes focus on the drops of water, you will see that images further back in the mirror will not be in focus, and vice-versa.
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why do some insects not fly as well as others, such as June Bugs, Crane Flies, and some other types of flies?
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It's less that they weren't meant to fly, and more that the ability to fly is useful but secondary. Insects like bees and flies use their ability to fly to constantly roam in search of food, but there are insects with wings that don't actually fly, like grasshoppers. Lots of beetles, too, can fly but prefer not to unless they need to move quickly for some reason.
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I'm not an expert on this topic, but I believe it has to do with the simplicity of the fly's "brain". Insects like flies have only a very basic nervous system that's programmed to accept rudimentary inputs, like smell and touch, and use them to search for food, breed, avoid predators, and that's about it. You can think of them like very dumb robots. This simple programming sometimes results in the insects getting stuck in a behavioral loop. The fly will eventually be able to escape this loop when a small variable change in their environment alters their behavioral pattern.
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How come that a negative multiplied by another negative becomes a positive?
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The opposite of the opposite is back to normal. If you turned something inside out twice, it would be back to normal. Same as if you turned it around twice. On a number line, the number 5 is five units to the right. If you do the opposite of that, you go left 5, to -5. If you go the opposite of left five (the opposite of the opposite) you're back at 5.
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I may not be qualified to answer this, but the simple answer is, there isn't. There are opposite charges that exist, and we simply label one negative and positive to denote them for the purposes of using them in equations so they will balance out properly so long as we are consistent in saying "this one is negative and this one is positive". There is not a fundamental difference I do not believe, they are simply opposite.
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If someone is shot in the heart why do they die instantly rather then when all the blood it pumped runs out?
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They do not die instantly. But the brain needs a lot of energy - it needs a nearly constant flow of blood. Stop that for a few seconds and the brain stops working properly. If the blood flow stops for other reasons, it can be possible to survive if blood circulation is restarted quickly (e.g. via CPR). But without an intact heart, there is no way to restart the blood flow. The person dies.
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It wouldn't be completely instant, but a bullet to the heart would cut off blood flow, which would in turn, stop oxygen flow (because oxygen needs blood to flow). This would halt your brain processes because your brain requires constant blood and oxygen to operate. This would all happen pretty quickly but not *instantly*
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Can radio waves be considered light?
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Radio waves are absolutely light, as are infrared waves, visible waves, ultraviolet waves, and x-rays! Another way to put this is that all of these waves are just different frequencies/wavelengths of **photons**, and photons are light. Everything on the [Electromagnetic Spectrum](_URL_0_) is light. Edit: There's been some talk about nomenclature below. While in the common vernacular "light" may be used interchangeably with "visible light," that is not the formal, scientific definition of "light." [Here is a link](_URL_1_) to the first page of the introductory chapter of *Spectra of Atoms and Molecules* (2nd Edition) by Peter Bernath, one of the definitive texts on Spectroscopy - the interaction of light with matter. Hopefully it's of some interest!
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Yes, radio waves are (or consist of) photons too, and they have lower frequency (lower energy) than photons you can see with your eye. The energy of a photon impacts its 'absorbability' by various substances, too.
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Carbon vs. Silicone in transistor construction... which is better?
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Just to clarify, *silicone* is different from **silicon**. CPUs are mostly made of silicon, they don't have silicone in them. One key advantage rests on the fact that Si-Si bonds are weaker. It means that the Si lattice can more easily accommodate foreign dopant atoms compared to its carbon analogue. As a result, it is possible to vary the electrical properties of Si with relative ease. Not so with diamond, say.
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Silicon and Carbon, despite being in the same column on the Periodic Table, have fairly different properties. In particular, silicon does not form long chain molecules as easily or as frequently as does carbon, and those long chains are essential to organic chemistry.
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If a father has cancer (specifically testicular) at the time of conception, does this have any ramifications for the child?
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To add to this, if a pregnant mother has cancer can it metastasise to the foetus?
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There are lots, but one *major* issue that contributes to many cancers is recombination. Normally recombination isn't really a bad thing, and gives us genetic diversity. When your cells are dividing to make sperm or eggs, the chromosome you have from both mom and dad line up. Because they are structurally similar, it is possible for them to "swap" segments, [like this](_URL_0_). This means you could pass on one of your dad's chromosomes, but with your mom's "blue eyes" gene inside of it. The problem comes in when the swap doesn't work very neatly. Instead of having Chromosome 9 swap with another Chromosome 9, it might swap with Chromosome 22. Sometimes this is fine because the DNA is *still there*, but in different places. However, it often turns out that DNA is lost, or gets coupled to another segment of DNA that makes it inappropriately active.
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How do the speakers and mics of waterproof smartphones work (like the IP67 iPhone 7)?
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Most are "water resistant" meaning you can't keep them submerged for long - accidental drop in the toilet or sink, no problem. The internal design features very thin filaments that don't obstruct sound waves much. Notice how the iPhone 7's design features a much louder speaker? I assume it would be even louder without the water resistant material
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This is a really fast response, but there are little rubber rings that create seals between the phone cover and the body of the phone. That way the charging port and the battery and things stay dry because water cant actually go into the main part of the phone.
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How is it that electric eels can deliver up to 600 volts that stuns their prey, but they themselves don't get stunned?
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> Nobody knows exactly how the electric eel keeps from shocking itself, but the best working hypothesis is that the vital organs like the brain and the heart are located as far as possible from the electric organ (up near the head), surrounded by fatty tissue that acts as an insulator. In cross section through the tail, the electric eel is nearly entirely electric organ. _URL_0_ More info: _URL_1_
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Eels have three organs in its abdomen responsible for its electricity. The electric eel generates large electric currents by way of a highly specialized nervous system that has the capacity to synchronize the activity of disc-shaped, electricity-producing cells packed into a specialized electric organ. The nervous system does this through a command nucleus that decides when the electric organ will fire. When the command is given, a complex array of nerves makes sure that the thousands of cells activate at once, no matter how far they are from the command nucleus.
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Why do people have panic attacks?
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Panic attacks tend to occur in people with relatively high levels of interoceptive sensitivity. In other words, they are very sensitive to sensations originating from their own bodies, such as changes in heart rate, sweating, feeling slightly out of breath, etc. This sensitivity to these sensations, coupled with normal variations, such as your heart skipping a beat or heart rate increasing, can feel like something is "wrong," which induces fear, which increases heart rate, respiration, etc. and so on in a positive feedback loop. There's some evidence that people with panic disorder (repeated panic attacks and the fear of future attacks) have relatively less stable respiration during sleep, which may be the trigger of nocturnal panic attacks. Psychological treatment of panic attacks includes breathing retraining (learning to breath slowly and smoothly to combat hyperventilation), reappraisal of fears, and habituation to panic-inducing sensations.
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Anxiety can trigger the fight or flight reflex which releases adrenaline which raises your heart rate.
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What's the difference between the Holocaust and the Shoah?
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Shoah is a Hebrew word, which means "disaster." Holocaust is an English word derived from Greek, and as you pointed out, it means a sacrifice that's entirely consumed by fire (as opposed to other sacrifices, where only part is burned up and the rest is eaten), so it came to mean a total massacre. They refer to the same event. Because "Shoah" is the word that Jews designated for themselves, some historians use it too, as part of letting oppressed peoples define their own history, similar to how historians increasingly use native words when writing about native Americans, instead of the words chosen by colonists.
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By no means am I discouraging anyone from giving you an answer to your question, but our resident Holocaust expert /u/commiespaceinvader did a stunning job at talking about this, especially in this Monday Methods [thread](_URL_0_), where he and others discuss the issue
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My girlfriend insists on letting her restaurant leftovers cool to room temperature before she puts them in the refrigerator. She claims it preserves the flavor better and combats food born bacteria. Is there any truth to this?
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From _URL_0_ Mistake #5: Letting food cool before putting it in the fridge Why: Illness-causing bacteria can grow in perishable foods within two hours unless you refrigerate them Solution: Refrigerate perishable foods within 2 hours (or within 1 hour if the temperature is over 90˚F.
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The food spoils eventually anyway. It will probably be a mold. Life exists in a temperature band. Humans are warm blooded. We keep our body temperature very constant. Bacteria are much too small to do this. There surface area to volume is much too great. Bacteria have to exist at room temperature. But they will still grow best when warm. So if you keep food at room temperature bacteria have a chance to grow. Get a food to blood temperature with bacteria in it and they will grow very quickly. Mayonnaise at blood temperature which is not sterile will sicken you in an hour. Food at hotter temperature is too hot for bacteria to grow. It becomes sterile. Bacteria in it die. Foods kept cold with ice will not be a good place for bacteria to grow. That is why food is best served hot, or cold. Food in the refrigerator is kept too cold for bacteria to grow. Eventually molds will grow slowly at that temperature.
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Can you easily break somebody's neck by twisting their head quickly, like in the movies?
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I read this question answered a few months ago on here. Basically the top comment said that a person's neck muscles are super strong, so that unless the killer really surprises the person being killed, the person could tense up and fight them off.
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Your neck is very vulnerable, even if you know you aren't going to get hurt, your subconscious still reacts instinctively and tries to protect your neck.
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How are plastics made and why are they so popular?
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Plastic is a oil based product and it is really cheap to form plastic compared to metal. But because it's really easy to for its not strong therefore it needs to be replaced often. Also because of the nature of plastic it easily degrades. This Is just a quick and dirty explanation until someone who knows more comes along.
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Plastics are polymers, they are made by polymerizing monomers. That means you get smaller molecules (monomers) to link together like a chain into long molecules (polymers), usually with a catalyst. Polymers can release monomers when heated, and it's the monomers that can conceivably be unhealthy. [Polycarbonate plastic and bisphenol A precursor monomer](_URL_0_) for example. I feel like I should add there are many different plastics. Some are pretty safe, even when heated. Polyethylene, which they make tupperware and cutting boards from, is just polymerized ethylene, and is about as dangerous as candle wax. Unless you know what plastic your soy sauce was in, who can say. In general though, food grade plastic is not a significant hazard, so long as you don't burn it.
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When a small bird defends its nest against a large bird, what threat does it actually pose?
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I think you're reasoning that a large bird could obviously beat a small bird, so why bother defending the nest if the large bird knows that? Well if the two bird were to enter into conflict, it would come at a cost to both of them (energy, risk of injury, risk of predation, etc.). Now a bird defending its nest is going to be more likely to risk these costs, because its fitness is tightly linked to offspring survival. A large bird might just be sacrificing dinner. It's an extension of the life-dinner principle. I'll add that, although size is very important in determining the outcomes of conflicts within species, it's not always a great predictor between species. Sometimes smaller species are better/quicker/meaner than larger species.
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All large birds of prey are vulnerable to predators when they are on the ground, but there aren't any animals that actively hunt them. As eggs and nestlings, they are very vulnerable if a parent is not on the nest.
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why can't you drink an object floating in a glass of liquid?
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The object is floating in the water. As you tilt the glass to drink, the object continues to float in the liquid (after all, water ~~is heavier than the object, and air is lighter than the object and the water~~ its mass is higher), which means the object will go up as you tilt your glass. This is why it's hard to swallow an ice cube, unless you take large gulps.
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The dissolved gases need the right conditions in order to coalesce. Usually this means they need a micro cavitation to begin forming bubbles. At a microscopic level, the bottom of a glass has enough little pits to begin forming bubbles. The dissolved gases want to get free of the drink, but usually can't due to the pressure of the liquid keeping it dissolved. Once it finds an outlet to create bubbles, it tends to keep forming in that same location.
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If I fired a conductive chain from the ground up into the clouds during a thunderstorm, would lightning 'follow' along the chain?
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Yes, this would work. In fact, [it is already done on a regular basis](_URL_0_) by lightning researchers, launching rockets into thunderstorms which trail a thin copper wire behind them attached to the ground. These [lightning rockets](_URL_1_) are apparently effective at inducing lightning when the right conditions are present, but for the life of me I can't find any solid data on just *how* effective they are. Every study I read omits the number of successful vs unsuccessful launches, and the parameters that determine launches. So, sadly, I can't give you a better answer than "it can work some of the time".
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If you watch a [slow-motion video](_URL_1_) of a lightning strike, you'll see that before it hits the ground it sends out small "feelers" that go out somewhat randomly, but mostly downwards. Once one touches the ground, the path it took gets very bright (this is the most visible part of a lightning strike) as it carries a massive current between the clouds and the ground. Lightning happens when there's a big enough potential difference between the clouds and the ground so the air breaks down. The plasma created by the initial electrical breakdown follows the local path of least resistance, which is why it moves randomly, but then once there's a line that touches the ground and lets the potential difference equilibrate all the current travels through that path.
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What can Obama do before he leaves the presidency?
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Nothing beyond his current Article 2 authorities. And that's the point. Imagine 4 or 8 years from now... would you want the outgoing president to have unlimited, autocratic power? Peaceful transitions of power are essential to our nation. Those unhappy with the result of the election get another chance to vote for a president in 4 years. And, get another crack at shaping Congress in 2 years. Maybe it's going to be a wild ride. Or, maybe nothing of consequence will happen. Who knows. Edit: Other posters mention Executive Order. They do have the force of law, but only after they are codified in the Code of Federal Regulations. That takes a lot longer than 60 days.
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Mostly it is to prevent a popular president from accumulating too much power in the government. A leader who stays too long tends to make the organization about himself whether he wants to or not. Things get structured around how he operates, and people defer to him based on his experience. When he leaves his post, especially if it's a sudden departure, the organization is crippled without him. Not something you want to happen to a government.
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Who is the longest ago person that we have hard evidence lived?
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There's definitely more to be said, but there is a [part of our FAQ](_URL_1_) which has some answers which address similar questions to these: * [What's the oldest recorded part of history that is so old that we literally can't obtain any information on anything older (ie. then up to religious interpretation)](_URL_3_) *by /u/tweedy_impertinence* * [I recently read a quote saying people die twice. The first when they physically die and the second when the last person that knows their name dies. So who's the oldest person we know the name of?](_URL_2_) *by /u/kookingpot* * [Oldest person we know to have existed?](_URL_0_) *by /u/Tiako*
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Given that we have [evidence of humans (Homo erectus) using fire from 1 million years ago](_URL_0_), and that is far from the oldest evidence of hominin activity on the planet, I would say that it would last for a very, very long time. I was just on an excavation this summer that demonstrated evidence for human occupation at the site of [Ashkelon](_URL_1_) from around 3000 BC (Chalcolithic-EB1 transition). There is no doubt that evidence of human occupation can stick around (and does stick around) for millions of years. An exact number would be difficult, but would be quite high.
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If you were inside a giant hollow metal planet, where would the gravity pull you?
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I think you would feel no force anywhere inside the giant hollow metal planet (assuming it is spherical), and outside the planet gravity would act so that it would be the same as if all the mass of the planet concentrated at the center. ***Proof:*** (WARNING: MATH): We will use Gauss's Law for Gravity: _URL_0_ We know that the gravitational field inside the sphere must be radially symmetric, since the planet is radially symmetric. Hence, by Gauss's Law for gravity, integrating around a closed shell of radius r < R of the shell, we have that 4 pi r^2 |G| = -(4 pi G)* 0 = 0, and hence |G| = 0, since 0 mass is contained inside this Gaussian surface of radius r. Further, for r > R, 4 pi r^2 |G| = -(4 pi G)* M, and hence |G| = -GM/r^2, which is just the gravitational field for a point mass M at radius r.
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As you approach the center of the planet, the force of gravity will increase for a time (the center of the planet is denser than the outer layers), then start to decrease fairly steadily as more and more mass is located "behind" you to cancel out mass "in front of" you. At the center of the planet, you do not feel any affects of gravity from the planet. This is not to say your wouldn't be crushed - the pressure would be beyond immense. To further expand upon how gravity works inside spheres, if you are inside a hollow sphere, no matter where you are on the inside you will feel no force of gravity from the shell. So for example, if you hollow out a 100 kilometer sphere at the center of the Earth, no point within that hollow space will experience gravity from the planet (even against the edge). Newton's Shell Theorem shows this nicely.
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What weren't the tight, stacked columns found in infantry formations during the 18th/19th centuries completely demolished by cannons and other artillery?
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The thing here is that infantry regiments typically marched in columns and formed rows in battle. Formations were not as tightly packed as you would believe because the primary purpose of these formations were to present the greatest amount of rifles to bear to the enemy over the maximum effective area. Thus the line would be two or three deep and this reduces the likelihood of a cannonball scything through the ranks, although it was likely that this was a fairly regular occurrence, particularly if the ball skipped upon impact.
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More can be said here, but /u/vonadler's old response [here](_URL_0_) might be of interest regarding artillery of the period.
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How do companies know your credit card is valid without charging them? (For free-trials and what-not)
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It's possible to "pre-authorize" a charge, which is done when you place an order that won't be shipped immediately. So they can effectively ask the card issuer "if I were to ask for $1 from this card, would you say yes?" without then charging the card.
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You dial a toll free number first to connect to the company that issued the card, then you type in the code and phone number to tell them who you are and who you want to call.
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What is happening in my brain when I get embarrassed? Does it serve an evolutionary purpose?
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From a evolutionary psychology standpoint, yes, it does serve a purpose. It was essential for survival that we "fit in" within our tribes, and when we sense that we did something that ostracized us from the rest of the tribe, our brain tells us so by making us feel embarrassed, thereby telling us to not do it again. It's essentially a survival instinct; failing to fit in could lead to expulsion from the tribe. Of course now, what causes us to be embarrassed is different, and a "tribe" isn't really needed as much for survival, we still desire to be accepted in a social group. As to what is going on in your brain, it's your brain releasing the appropriate chemicals after analyzing its environment, like any other emotional response.
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There is no such thing as "purpose" behind biological features of humans or any other natural organism because we were not designed, only functions which such features perform and impact our rate of survival. Embarrassment is a feeling of discomfort which tends to cause us to seek the acceptance of the community and social group in which we reside. This is very important to our survival because we are social creatures which are heavily reliant upon others in order to thrive. Being a social outcast would not only greatly reduce or remove the ability to reproduce successfully but would often actually result in the death of the individual. Ultimately then embarrassment exists for the same reason pain exists, as a prod to avoid harmful and life-threatening behaviors.
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What happens after a company is bought out?
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The new owners take control of the company and run it as they see fit. Often, this will involve some restructuring - perhaps laying off employees, hiring new ones, selling assets, or buying new ones. In the case of a merger, assets and employees deemed to be redundant may be let go (for example, the newly merged company probably doesn’t need two payroll departments). Otherwise, it’s generally business as usual.
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You're thinking too hard about this. The (old) company has a owner. Now it has a new owner now. It's no different than if Bob sold his company to his buddy Jerry. Thats it, now Jerry is in charge and owns the company.
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how can a cell somewhere in your body have a completly diffrent function than a cell elsewhere in the body even though they contain the same DNA?
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Yes, they have the same DNA however they differ in which genes are 'turned on' or 'turned off' which determines the function of the cell. Genes are the smaller units of DNA. Imagine each gene was just an 'on/off' button and there were only 2 genes in DNA. Cells would then be able to have DNA which was 'on,on', 'on, off', 'off,on' or 'off, off'. Now imagine these 4 combinations all had different functions. Essentially that's how cells have different functions.
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different areas of the dna are modified in different cells so they are more or less accessible to the enzymes which transcribe it into rna. different patterns of accessibility = different type of cell. epigenetics yallllllll.
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Why is Ford advertising the Transit (commercial van) so heavily.
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Because it is a huge profit maker for Ford. The van is built in Turkey as a passenger van and then shipped to the US. The passenger parts are stripped out and then sent out to dealers as a professional van. The reason for this is bypass a US tariff on professional vans which is not on passenger vans. Originally the Transit was thought to be a niche product, but has really not been the case. There is a huge upheaval in the professional van market, the days of the Astro/whatever Chevy has is now waning. Nissan is also advertising their NV2000 as well. Fun fact, the MB Sprinter is built in Europe, then disassembled, shipped to the US, and then reassembled to get passed the same tariff that Ford is doing.
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The biggest reason is the market. Ford could make something that looks like a supercar, but it wouldn't be profitable for them to do so. A company like Ford makes money in volume, so they make cars that appeal to large numbers of people. Supercar manufacturers make fewer vehicles, but charge more for them, and so can be more esoteric in their designs.
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Why do certain foods give you diarrhea an hour or two after consumption when it takes 8hrs to go through your entire digestive system?
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Well Timmy, your body needs food for energy, and they need all kinds of different food for different reasons. If your body doesn't need any more nutrients from the food, it releases it and you poop. Those are the ideal circumstances. When the body encounters a problem, and doesn't trust the food you've given it, it speeds up the release process and waters it down so it passes more quickly. This can happen if you're sick, and the body is rejecting some foods, or if there's something wrong with the food and the body needs to get rid of it to keep you from getting sick.
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How do you know the poop that comes out of you 2 hours after McDonalds has anything to do with it? Developing the need to shit shortly after fast food is not the same as that food going right through you.
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Is there a limit on how much space SD cards/USB drives will have one day?
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There certainly are physical limits to data storage. The [Beckenstein bound](_URL_2_) ([paper](_URL_0_), [pdf](_URL_1_)) gives an upper bound on the information that can be stored in a given volume and mass. [Here is an article](_URL_3_) ([preprint](_URL_4_)) which tries to determine the specs of an "ultimate laptop" weighting one kilogram at one liter volume. In section 2.2 Lloyd comes up with roughly 10^31 bits memory for this ultimate laptop. Scaling this down to a microSD, which has about one ten-thousandth part of that in volume and mass, one gets roughly 10^27 bits of memory, which is approximately one hundred million exabytes. (This actually seems surprisingly small to me, did I make a mistake?) This limit can be overcome by making the card heavier though until you basically create a black hole. All of this is however not really relevant to practical limits which are probably much smaller due to technological considerations.
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Different standards. There are three different types of SD formats, these also apply to MicroSD. SD: Up to 2 GB SDHC: Up to 32 GB SDXC: Up to 2 TB, although cards of that size don't exist yet. People have only been able to make 256 GB MicroSD cards, and those are still very expensive. So when a phone manufacturer says it can take MicroSD cards up to 128 GB, it means it can take SDXC cards, but they don't want to be misleading so they say 128 GB instead of 2 TB.
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During WWII, did Italy want to recreate the Roman Empire?
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Not recreate as such, rather they (the fascists) saw themselves as the inheritors of the Roman empire. This was known as 'Romanita', and effectively drove/justified their expansionist policies. I've some interesting links/articles etc. I'll post later (got to get on with putting the kids to bed!) Edit: So, Dyson's book is wide ranging, but had some interesting chapters on Italian colonialism: _URL_1_ David mattingly has also written extensively on the subject, mostly relating to archaeology in north Africa on this context. See especially his article in this book (don't know of an online copy, sorry): _URL_0_ (As you might have noticed, most of what I know is from an archaeological perspective)
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The Italians performed very poorly in the Second World War. Apart from its strategic position in the Mediterranean Sea, the Italians caused more headache then advantages. Mussolini decided (without informing Hitler) to invade Greece, delaying operation Barbarossa with some critical months. The Italian invasion in Egypt failed also, enabling the British to route the Italians into Lybia, and thus forcing Germany to assist. During the invasion of Sicily and later on the Italian peninsula, the Italians capitulated and Germany and Italy became each others enemies. The Germans put up a lot of reprisals and Italian partisans waged a bloody war against the Germans. Surprisingly, the relationship between Hitler and Mussolini never suffered, Hitler held Mussoline in high regard and even liberated Mussolini form its Italian captives and helping him to setup a puppet state in North Italy.
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How are sport game statistics recorded?
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It's a mix. There'll always be a human element but new technology is always being introduced. Players do wear things that can track things like how far or fast they're running. When I was in college they always made a big deal when ESPN came to talk to the statistics majors and hire a few to work for the company.
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There was a great short YouTube documentary about the company that does this for the Premier League posted in r/soccer a while back but I can't find it right now. Basically there are a bunch of guys who sit around and watch certain games on computers with special software that lets them keep track of all this stuff. They have to be really fast with a mouse and keyboard, like professional starcraft fast, so it's a lot of college age guys doing it. I think the name of the company is Opta. edit: [Here's the video](_URL_0_)
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Relativity: if acceleration is constant, what would the distance be versus time?
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What you do is you take the speed you think you'd be going if you ignored relativity (this is called the rapidity). Then you take the hyperbolic tangent of the rapidity divided by c. That is how fast, relative to light, the thing is actually going. If you want an equation, it's v=c x tanh (a x t /c) Where v is velocity, a is acceleration, c is the speed of light, and t is time.
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I think what you're asking for is what units we use, as in "kilometers per hour". If that's correct, you could separate the space and times components and say "meters per second" for space and "seconds per second" for time, although this is simplistic. This may not be the best ELI5, but I'm not sure how else to explain it without talking about things like worldlines, relativity, and proper time, which are definitely not ELI5. You should ask this in r/askscience. You'll probably get a much better explanation.
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Why do Chinese companies go to such lengths to make a fake and sometimes not fake item but never spell check the packaging / manuals?
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2 things come to mind. Former employees or contractors learned how to make the item while working at the original factory and now brought this know-how to a similar plant to make it themselves. Or the item is reverse-engineered/cloned and sold as a knock-off. Now the name: to avoid trouble (in China, not here) they slightly change something like the product name 'Camon' or put an obvious mistake in the manual/packaging to show, "See? Not the same! This is our design."
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Well, a word in Chinese is made of "Characters" which have their own basic meanings as words. Add two characters together for a more complex idea. Example: to say "COMPUTER" in Chinese you would use the characters for "Electric" and "Brain" together. That's the word "Computer." "TELEPHONE?" Ok, use "Electric" "Word" and "Machine." OH, but the Chinese people use this so often they frequently leave out a character or two and figure you'll understand from context. You can see how things could go very wrong very fast, yes? A well-meaning Chinese guy wants to translate his clever slogan with an online translation program that knows nothing about context and, whammo, you've got a literal translation of chinese characters instead of a translation of meaning.
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When a server experiences too much traffic and goes down, what exactly do the server owners change to make it work again?
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Usually nothing. All that is needed is to stop allowing new connections/requests, flush out the existing ones and then put the server back online. The whole part where you wait around is sometimes just to get people to lose interest so that the server doesn't crash again. In most cases the server is simply restarted.
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Patches, configuration updates, policy changes, hardware upgrades...any number of things that would affect any other server on the Internet.
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Why do cigarettes have thousands of chemicals in them? Shouldn't it just be tobacco and rolling paper?
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Because tobacco is a plant and most complex living things consist of hundreds if not thousands of chemicals. It's not just 'tobacco' and 'rolling paper' because those aren't chemicals.
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The horrible chemicals aren't packaged into the cigarettes. They're created when you start burning the tobacco.
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In Medieval Warfare, what was the role of chainmail and how much protection did it offer?
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Chainmail was definitely invented before medieval plate armour, and was the big thing in protection for several centuries, the peak being the 11-13 th centuries. A well made maille armour can protect you from nearly everything you'd encounter on the battlefield at that time. It is basically immune to sword cuts, it handles thrusts and arrows pretty well. However it did not protect that well from blunt trauma - axes and hammers for example. Usually maille would be worn with a thick tunic, kaftan or gambeson, to help with the blunt trauma and to add some additional protection. Overall maille was very useful and it did its job pretty well - after all you don't get to see battlefield use for more than 2000 years if you're ineffective
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From the perspective of a skilled armorer, chainmail is actually easier to make, since the rings can be made by apprentices or (in Roman times) slaves. Plate requires far more man-hours from a master smith, and it needs more work to make it fit the wearer well. "Chainmail" is actually a neologism, invented in the days when Victorian scholars were obsessed with classifying everything. At the height of it's use in Europe (800-1300) armor made of interlocked rings was just known as "mail"
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Why does plastic when bring stretched or ripped get warm?
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Friction between the molecules making up the object, this is not unique to plastic, any material will warm up when being bent or stretched because you are causing movement and therefore friction
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There is no one "plastic", and something like shrink-wrapping is a one-way process. Plenty of plastics that shrink in cold conditions will expand under warm conditions though. Here's a nicely detailed answer with some ascii graphics: _URL_0_
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What are imaginary numbers?
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A number which doesn't belong to the set of real numbers (negative infinity to infinity). More specifically a number which includes the square root of negative one. Since it is impossible to have the square root of a negative number, it is very useful for many fields which find themselves working with the square root of number. The first place most people see them when in school is when working with quadratics. If a quadratic never intercepts the x axis (for example x^2 + x + 16). Then if you tried to solve for its roots (using the quadratic formula) it would yield the answer as: [1 +/- sqrt(1 - 64)]/2 This cant work because 1 - 64 < 0. So instead one can use an imaginary number (i = sqrt(-1)). Thus the equation becomes: [1 + sqrt(63)i]/2 This may not seem useful, but in math, engineering and physics (and maybe more i haven't used it for) it can become very useful.
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[It's not a coincidence](_URL_0_)...but how deep the connection is, is a matter of opinion. When you just see it with no explanation it seems extremely profound, but when explain it in terms of rotations through the complex plane, e^(pi i)=-1 is basically just saying "When you rotate 180 degrees (pi radians), you're facing backwards (1 to -1).
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Do seedless watermelons procreate? If so, how?
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[Seedless watermelons are particularly interesting because they must be propagated by seed, and yet growers can still exploit parthenocarpy. One way to make seedless watermelons is to produce triploid seed. As in the case of bananas, triploid watermelons cannot produce functional seed, but they still develop good fruit through parthenocarpy. Plant breeders produce triploid seed by crossing a normal diploid parent with a tetraploid parent, which itself is made by genetically manipulating diploids to double their chromosome number. In the case of watermelons, this manipulation has to be performed each generation, so it is a somewhat expensive proposition but still worthwhile. ](_URL_0_)
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Same as any other fruit. They are ment to be nomed, and use the animal poop as fertalizer. Or if they fall to the ground, seeds incased in rich fruity energetic goodness, just right enviorment for the seeds to grow into lovely baby seedlings < 3
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Why are companies allowed to lobby politicians?
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> To me it seems wrong that private companies can lobby politicians and pay them what to think. "Lobby" doesn't mean "bribe", which is what you're describing. Lobbying just means petitioning, or asking them, or talking to them. You have the right to lobby as well, and there are many groups that act in your interest to lobby politicians. One example is the ACLU.
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The term "lobbying" originated in the early days of the Republic, when Congressmen usually lived in hotels. A "lobbyist" was someone who would wait in the lobby for them to come down so they could speak to them about something. Most lobbying that happens today is just that: a way for people to let Representatives know how they feel about different issues. It's not just corporations who have lobbyists: teachers, doctors, environmentalists, unions, gay-marriage advocates, civil-rights organizations and just about every interest group that you can think of has them. You might ask why these companies and groups don't just send someone from the company instead of hiring a lobbyist, and that's because lobbyists are much more familiar with how our government works (many of them are former Senators and Congressmen). They have personal relationships with sitting representatives, they know who to talk to if something needs to get done, and generally know the best way to advance their client's interests.
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Antimatter / strange matter. What is it? How does it work? Where does it come from?
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Every charged particle has an antiparticle which is essentially the same thing with the opposite charge. The antiparticle of the electron is the positron, and it is released in some forms of radioactive decay and used in medical imaging technology to detect cancer. Antiprotons are created in particle colliders, and sometimes bound to positrons to create and study antihydrogen. Strange matter is matter made of things that are like protons and neutrons but bigger and less stable. This is not known to exist, except that these particles are made transiently in particle collisions.
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Antimatter is matter with opposite charge. Anti-electrons (positrons) have the same mass and spin as an electron, but an opposite charge. When particles collide with their antiparticles, they release a lot of energy.
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LI5, what is the difference between Army infantry and Marine infantry.
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Originally, the USMC were part of the Navy. Essentially, the ships would get close to land and drop off the meanest sailors, give 'em swords and maybe a musket, then pull away. Those guys were the Navy's infantry, and later the Marines. Eventually, they broke away from the Navy, but are still closely related to them. While the Army is the main ground force for the USA, the Marines usually are the ones that assault beach-heads and conduct amphibious assaults.
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The idea is that the USMC can serve as a fast reaction, forward deployed force. The army isnt neccesarily set up to have forces of various, but usually smaller size forward deployed at bases around the world. How have MAGTF's (Marine Air Ground Task Forces) of various sizes, at the smallest it will be an infantry battalion, along with some armor, some logistical, and some air support, which you can all load onto a couple of USN ships and sail around until needed. The USMC is set up both structurally(all branches within one, and strong cross training with USN), and doctrine wise to do that (focus on warrior ethos/smaller more multi task units), to go into situations with minimal outside support, and to make do. The Army meanwhile is the big shock and awe force which comes with everything you can imagine and then some. The USMC is then the smaller faster sword, to the USA's giant 105mm howitzer.
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How did the American Mafia go from its peak in the '40s/'50s to its state of decline in the early 21st century?
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The American Mafia really peaked in the '20s and '30s. It was already in a state of decline by World War II. There were a lot of contributing factors though, including the focus on the war. Young men joined the army instead of joining gangs. Resource laws and restrictions on gasoline and food (and especially bullet) use helped choke them out. At the end of World War II, America's mafia system returned somewhat but it was never the same as during the '20s and '30s under big names like Rockefeller and Pendergast and Capone. In the '60s, what with the Civil Rights Movement and whatnot, street gangs started popping up between different ethnicities to help protect themselves from other ethnicities and corrupt cops, and the Mafia was completely choked out and went the way of the dodo.
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In the eastern coast of the United States the Mafia is still around and active, but definitely weaker then in the 1960s. Italy is a corrupt rats nest, mob is the curse of their culture and leg breaking is ubiquitous. They operate all over Western Europe though, they rule the drug trade there. Russian mob is quite the beast, they are all over the grey wastes of that empire. They are very much present even in countries nearing Russia, they are also a problem in South Korea. Yakuza are scary motherfuckers, if in Japan, avoid them. You could easily see drug cartels as the Mexican mob.
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