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If ice expands when it freezes, and one of our poles doesn't actually have land above the sea, why are we worried that the ocean levels will rise with polar sheet melts?
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You are correct that the major concern for sea level rise is Antarctic ice flowing off the Antarctic continent and into the ocean. That and Greenland ice. Arctic ocean ice melt will not directly affect sea levels.
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> but in any basic science class one learns that solid ice has a greater volume than water; wouldn't melting the polar ice caps lower the sea level? In any basic science class you should also learn that ice displaces the same volume of water as it would as a liquid, the rest extends above the surface. So theoretically, it would do neither. However, as others note, the problem is that a lot of ice is on land, which melts and runs off into the sea. So what you actually have is the addition of a great amount of liquid water to the ocean.
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the difference between financial aid and student loans?
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In the US, *financial aid* is an umbrella term for any kind of financial assistance available to people attending university. Student loans are one kind of financial aid. There are also a bunch of other programs, including grants, scholarships, and work-study programs. There are hundreds of different kinds of grants and scholarships, which all have their own criteria for eligibility. There are certainly some that have age-related restrictions.
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Students here file a FAFSA (Federal Application For Student Aid), which is a way of saying "Hey, government, I'm not rich as fuck. Here's how much money I have, here's the college I want to go to, can ya help me out?" And then if you get approved, they send you some money that you don't have to pay back, provided you maintain certain things (at least so many credit hours, etc). If you drop out or fail to meet their rather low criteria then you have to pay it back. Usually that's not enough to properly cover an education, but it's a significant help. There are student loans but it seems everyone does them slightly differently.
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How do makers of animal skin clothes prevent the material from rotting
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Chemistry is the simple answer. Through exposure to heat and chemicals, the structure and properties of the animal hide can be changed to make it resistant to water and rotting. There are a number of different processes that can be used, and this wiki article has a pretty good overview of the main ones: _URL_0_
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Clothes are usually immersed in a vat of chemicals (that are reused and filtered for the old dirt) and agitated like water wash but without water. Chemicals are mechanically sucked out and they are steamed and pressed. Some more difficult (embellished) garments may only be spot treated, although the immersed stuff should also be checked for spots needing cleaning too. From what I understand suedes get color leaching out and need to have their colors restored. That was true 15 years ago, not sure as formulas have changed. I know the old stuff had a lot of suspected nuerotoxins, and my professor (a DC expert) advised to hand things outside for a day to release the volatile compounds.
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Why exactly do objects make "wooshing" noises when I drive by them with my windows rolled down?
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I suspect that you may be talking about something other than what SausageMcMerkin addressed. Do you mean the quick "whoosh" sound caused by passing stationary objects by the roadside that don't make noise themselves (like mailboxes, parked cars, etc)? If so, what you're hearing is simply a reflection of the sound made by your tires combined with your car's engine noise. The noises generated by your car bounce off the relatively-flat face of roadside objects and are directed back toward you. You should notice that this effect is more prominent with larger objects, objects closer to your car, and objects with very flat faces.
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Sound waves are just waves of air pressure. When you leave a window open in just the right way, a lot of air enters the car causing pressure to increase. Once there is too much pressure, it releases and pushes air out. Then more air rushes in. It’s like pouring something onto a trampoline and watching the trampoline bounce. And you hear it because you hear air pressure waves.
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Bolt action rifles of the late 19th C (Q from Rules Roundtable)
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Small arms development in that period was extremely rapid. A LOT of that came from the drawn brass cartridge like Rusty said. This was resistant to moisture, accidental discharge, crushing, tearing, etc.. it was VERY robust for an army on the move. Plus it sealed the breach by itself, which means ditching the annoying and easily worn rubber gasket and avoiding excess gas and powder flying in your face. Additionally, the Chassepot relied on a fragile needle that would, at best, wear over time. The new firing pin system was much stronger. I cannot think of a single unit that would benefit or prefer muzzle loading though. Backing up though, I'm not sure of your focus on bolt actions. From my perspective I see them evolving (in a broad sense) as follows: * Muzzle Loading * Breach Loading * Metallic Cartridge * Repeater (see Siege of Plevna) * Smokeless * Autoloading (much later)
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Hello! Here are some examples of similar questions I could find by searching for "lever action" on the search feature if you want to take a look at more yourself This thread has several answers discussing why armies preferred bolt over lever action rifles. [_URL_2_](_URL_3_) /u/PartyMoses has a rather short, but decent answer on the problems with more complex lever action rifles when compared to the simplicity of bolt actionand /u/DanTheTerrible has a rather lengthy one discussing the US army's decision to adopt bolt action over lever action The answers in this thread are more about addressing the use of lever actions in world war one, namely Russia.[_URL_4_](_URL_5_) and finally I will leave you with this answer by /u/monkeymasher about some of the more technical advantages bolt actions had over lever action. [_URL_0_](_URL_1_)
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Why do human legs bend forward, while other animals (e.g. Velociraptor) legs bend backward?
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I believe that if you look at the back leg of a dog, for example, the "backwards" joint is the equivalent of a human ankle, and they also have a knee. Basically, if you walk on the ball of your feet, and had a size 30 foot, you'd be doing the same thing.
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Genetics, they are genetically predisposed to develop substantial amounts of muscles in the legs and tail to enable them to hop at speed to avoid predators, as well as muscles for fighting other males.
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How can a spacecraft like the Cassini travel 900 million miles to Saturn in seven years?
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Here's Cassini's flight path: _URL_0_ The majority of the velocity results from the gravity boosts the spacecraft received as it slingshot by the planets. You can see this in the animation. If you think the speed you calculated is fast check out Cassini's max speed as clocked by [NASA](_URL_1_): > "The maximum speed clocked by Cassini was 44.0 kilometers per second (98,346 miles per hour) relative to the Sun on June 25, 1999."
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Someone should double-check my math, but I'm seeing the deltaV for a Saturn V to be around 11.8 km/s. If you are "magically" placing a Saturn V in orbit at 100 mi. ASL, the corresponding orbital velocity is 7.81 km/s. So you have the potential for 19.6 km/s, which is quite a bit faster than anything man has ever launched. As far as how much further you can go, well, you could already pretty much go anywhere with a Saturn V. That engine was used to get to the Moon many times, including 6 lunar landings. In fact, it was designed to carry 100,000 lb (45,000 kg) to the Moon. And it was already capable of escaping Earth's orbit (11.2 km/s needed for that). So how much farther could it go? How much time do you have? Since this goes faster than anything we've made, it could go farther than anything we've launched.
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How do autopsies work?
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Autopsies can be very lengthy and detailed operations. Even a case which seems cut-and-dry may have additional facets. For example, someone was found washed up on the shore, but was their death by drowning? The lungs may be examined to see if water was inhaled, the brain to look for other signs of trauma, and the blood taken to see if drugs or poisons were present. It is a very "hands-on" practice, and a lot isn't fit for TV. A coroner or pathologist can do things a surgeon can't in terms of opening up the body and removing organs to be individually examined. Bodies which have been dead for some time may be decomposing and rotting: it looks much better on TV to show a computer screen with some vague "scans."
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They cant really. As you say, those injuries would be seconds or minutes apart. I'm studying medicine right now, and I've had to observe a few autopsies last year. They cant tell which came first or what. I mean sure they can differentiate between fresh wounds, earlier wounds, wounds from struggle, previous unrelated injuries etc but they cant determine the exact order in which the death blows were struck. CSI etc tends to add a lot of bullshit.
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Can any other animals appreciate music made by humans, even on some rudimentary level?
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Animals will hear the same sounds as we do; they may hear more or less depending on their auditory threshold (think dog whistles). To this effect, the qualities of sound, such as intensity and frequency, etc., will elicit some reaction in animals. It may soothe them or rile them up. Whether or not animals can "appreciate" music as humans do really depends on how well that animal can identify and process human emotions conveyed in the music. Animals that co-evolved with humans, like dogs and cats, might be able to pick out emotions given certain inflections or tones, yet they probably will not understand the words. Imagine listening to a song in an unknown language and style (music by aliens, perhaps). You would only be able to "appreciate" it if you understood alien music.
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There was a study done on shelter dogs - they slept longer and barked less when classical music played, compared to no music. Also, some guys composed music specifically so cats would like it. The same guys did music for monkeys too. Cows produce more milk when music is played consistently at milking time. Elephants can keep a drum beat better than an average person. Also birds. Just, in general.
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why its Carl's Jr. on the western half of the U.S and Hardee's on the Midwestern/some eastern
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Carl's and Hardees were originally different restaurant chains. Back in 1997, the parent company of Carl's Jr. bought Hardees and is slowly combining the two restaurants. I expect they will keep the names separate indefinitely, as there's no reason to throw away name recognition.
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Without knowing the full context of this expression, we can take this to be either a joke or an expression of the provincialism of an Eastern who does not understand geography beyond the Atlantic Seaboard. San Francisco has been consistently regarded as part of the "West" or better the "Far West." Although the frontier - what the East regarded as the west - extended gradually over time from the place "just beyond the settlement," by the mid nineteenth century the terms and the educated perception was locked in. The old west of the Mississippi and Ohio drainages had become known as the Midwest, and the land from somewhere just east of the Rockies to the Pacific Coast became known as the West. Your character in "The Great Gatsby" should have known this, so he was either expressing his ignorance or trying to be funny - only context can determine which.
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Where did we get the Order of Operations
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It's rules we came up with to all be on the same page. Order of operations has no more inherent meaning than reading left-to-right; it's just a convention for determining what symbols on a page mean.
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The order is just a convention so that you can avoid to write some parenthesis. (BTW, some programming languages usually have more operators and they don't all agree on the order, there is at least one PL which isn't using PEMDAS, cheap hand held calculator as well). Now it is possible to give an explanation for the order. Parenthesis are there where they are as it is their goal to change the order. Division is a kind of multiplication (by the inverse), substraction is a kind of addition (by the opposite), so they are done at the same time as the main variant. Multiplication is a short hand for iterated addition, and exponentiation is a short hand for iterated multiplication so you process the short hand before what it is a short hand for.
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Why does a mixture of ethanol and water appear to decrease in volume?
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The reason is that for the ethanol-water mixture, the partial molar volume (the additional increase in volume upon addition of a mole of a substance) is always less than partial molar volume for either pure component. In other words, for any molar fraction of ethanol adding a given volume of water will result in a smaller increase in the volume than if the initial solution were pure water (and vice versa). This can be quantified by the excess volume (the change in volume upon addition of one mole of one component minus the total volume of the initial solutions), which as you can see [plotted here](_URL_0_) is always negative for the water-ethanol system. The microscopic origin of this effect is that water-ethanol interactions are different from water-water and ethanol-ethanol interactions (the solution is not ideal), which results in a tighter packing of the mixed liquid than would be calculated from taking the weighted average of the densities of the two pure liquids.
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Ethanol is less dense than water on its own, but it is *soluble* in water so that when they are mixed it does not separate out like, say, oil. Since it is soluble, the two together essentially become a new "unified" liquid and the relative densities do not cause layering (like how dissolved salt or sugar does not separate out by density either). If I were to guess at what you are experiencing, it would be that you have ice in your drink, and the part at the top has simply been diluted more locally due to the melting ice.
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How did apex predators that existed millions of years ago go extinct? (i.e Terror birds, Megalodon, Levyatan)
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It's hard to pinpoint the exact causes ~~of~~ for most prehistoric animals and plants, beyond trying to extrapolate data from the scarce info we have. We can look at extinction events nowadays for clues though. Overfeeding and loss of habitat from environmental changes are the two biggest causes.
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The flightless, penguin-ish [Great Auk](_URL_1_) used to live in the North Atlantic (not quite at the poles, but [as far as Baffin Island](_URL_0_)). They are extinct now, but only since the ~1800s - largely due to human exploitation and hunting of Auks for meat and down, as well as the accidental introduction of egg-eating rats. So, up until Europeans came onto the North American scene, they were able to find food and avoid excessive predation successfully.
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Why are cells so small?
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Surface area to volume ratio. Huge cells are not practical in many cases because the volume grows much faster than surface area in a spherical cell, and the surface area limits how fast many molecules can be moved across the membrane.
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No. You can't just make something orders of magnitude smaller because ultimately organs functionality relies on cells, and cells function on a molecular level, and molecules have a fixed size. There is wiggle room in the number of cells in an organ, the number of molecules in a cell, etc, but you can't just "shrink" a cell as much as you want because it's made up of molecules and proteins with absolutely fixed size. For instance, there is NO variation in the size of a water molecule. And even things with some distribution are fairly specific, like the size of a stable micelle. You definitely get get a couple factors in size difference, but a person-- > ant is many orders of magnitude off, and so would definitely not function correctly. Things like shrink rays ultimately don't make any sense, because everything is made of atoms, which are identical and cannot vary in size.
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How do we know so much about atoms if they are so small that we can't even see them?
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Just because you can't see something doesn't mean that you can't measure it. For example, if I were to hide a magnet behind a wall, you would be able to take a piece of iron and determine all sorts of things about it such as the location and strength of the magnet. Also, we have seen atoms using a technique known as atomic force microscopy. I've attached a picture of some carbon atoms here: _URL_0_
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The main reason that you can't see pictures of atoms (and even smaller particles) is that the resolution of what you can see is inherently limited by quantum effects to approximately the wavelength of the light you are using to see it with. Human eyes can discern photos with wavelength down to approximately 350 nm. The diameter of a Uranium atom is approximately .3 nm. Fine, so you say, why don't we use some form of vision that light with much smaller wavelengths? And we do — that's what X-ray crystallography is all about. However, when you start using photons with very small wavelength, it turns out that they have very high energy, so when they strike the object you want to see, they easily knock it out of position. That turns out to be like finding out what a kitten looks like by throwing bricks at it.
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What is the difference between the Internet and the WWW?
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The most layman way I can think to describe this is that the world wide web (WWW) is a portion of the internet. The internet is essentially everything that is connected via a global network. The world wide web is a method of accessing specific parts of the internet. Primarily, it is the part that allows us to view webpages and web content and follow hyperlinks. Edit: trying to think of a good example, and the best I can come up with is that the internet is like all of the roads, bridges, planes, boats and cars that connect the places of the world. The world wide web is more like a map of those places.
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The primary feature of the internet when it was first designed was that nobody does. It was the cold war, and the US didn't want it to have a central point of attack that could take the whole thing down, so it was made to be a mesh. You can own a part of it - like Reddit owns _URL_1_ and the servers that power it, but they don't own the DNS servers that direct people to _URL_0_
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When a magnetic field 'reverses', does the field rotate or stop and restart?
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I think it makes sense to view the problem with the magnetic field generated from a loop of wire with a current. If you have a loop of wire there is a magnetic field that passes through the axis of the loop. The direction depends on the current, so to get a reversal of magnetic field direction, you'd have to reverse the current. This would mean, going to 0 current and then driving it the other way. So what you'd see is the field diminish in strength, until it hits zero, and then start increasing the other way. Now, if they are switching the polarity of the magnet, and not just rotating the permanent magnet, it should display the same behavior as our wire loop. To switch the polarity, you have to go through zero first (or physically rotate the object.) Now there are mechanisms for the breaking of magnetic fields. This is magnetic reconnection, and it is a violent process that is responsible for solar flares. That is not what's going on here.
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It goes away. It's gone forever. The electric fields in the +x direction gets cancelled out by the electric fields in the -x direction. The electric fields in the +y direction gets cancelled out by the electric fields in the -y direction. The magnetic fields in the +x direction get cancelled out by the magnetic fields in the -x direction. The magnetic fields in the +y direction get cancelled out by the magnetic fields in the -y direction. There's no "conservation of an electric field" law here; there's no law that says that fields need to be conserved. There is no "friction", no heat produced, no energy released. It's just a force getting cancelled out by another force.
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What is that weird smell that comes off old guitar strings?
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Rotting skin and sweat stuck in the itty bitty cracks of the strings. Most strings are a material that doesn't rust or oxidize, like silver or stainless steel. That'll have a bit of a metallic smell, but everything else is leftovers from the player.
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The strings are a combination of sweat, dead skin cells, and dirt. You're causing the thin, barely visible layer to roll up like a carpet and condense into something easily noticeable
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Why is water so difficult for 3d animation?
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Because there are so many elements which needs to be executed properly for the water to look realistic.
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Currently, water is not modelled as a fully interactive fluid simulation. The fluid simulations you'd see if you searched for them on YouTube are small simulations rendered for a long time in something like blender. They're not rendered in real time. Water in a video game is pretty much just a mesh that may move and reflect stuff to show the surface, but there isn't really anything to it under the surface besides filters to simulate the lighting effects of being underwater. Objects don't typically interact with it as if it were a continuous liquid.
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Why are totalitarian regimes like China and Saudi Arabia admitted seat on the Human Rights council?
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The member states are elected. There are 47 member states. Enough of them voted for Saudi Arabia and China for them to be elected. China is one of the most powerful countries in the world and has huge influence across the world. It is no surprise that they would be elected. Saudi Arabia is the largest oil producer in the world and probably the most influential country in the Middle East. It is no surprise they were elected either. Also, in theory being authoritarian does not mean abusing human rights, although there is more potential for abuse.
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They're a majority-Muslim Turkic minority ethnic group in the far northwest of China. Similar to a lot of other nationalist movements around the world, a lot of them would like independence. China isn't exactly known as a bastion of human rights, after all.
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If you lose your memories will you still have PTSD?
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It's actually fairly common and one of the criteria for PTSD to, partially or completely, lose your memories of the traumatic event. It's called dissociative amnesia. So the short answer is "yes," and the long answer is "you'll have to specify what you mean by losing your memories." With dissociative amnesia, you lose your conscious recall of the event, but the memories are still housed in the brain, they're just housed differently. Someone smarter will have to ELI5 the exact neurological mechanisms at play. Edit: For the curious, the criteria for PTSD are here: _URL_0_ Dissociative amnesia is #1 under Criterion D
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PTSD is basically just bad memories on steroids. A person experienced an event so disturbing and shocking that they cannot forget it no matter how hard they try, causing them to have extreme cases of anxiety and panic attacks which gets in the way of their daily life; like sleeping or socializing.
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Is reinforced concrete able to function as a faraday cage? And if so does it make a building save of EMPs?
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The gaps between the iron bars in the concrete must be in the order of magnitude smaller than the wavelength of the signal. So it might function for low frequency radio.
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For a time varying magnetic field: [Faraday cage](_URL_1_). For a static magnetic field: [mu metal](_URL_0_).
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Does any of the original celtic languages remain in modern English?
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Not really in england. While england was a Celtic nation at one point, it has not been for much longer than scotland, ireland and wales. In those languages celtic influence is still prominent. There are many people who do not consider england or the english celtic at all, rather a mix of anglo saxon and Scandinavian.
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There are two surviving branches of the Celtic languages: the P Celtic ones like Welsh, Breton, and Cornish, and the Q Celtic ones like Irish, (Scottish) Gaelic, and Manx. There's a lot of mutual intelligibility between Welsh and Breton, and some between Irish and Gaelic, but virtually none between, say, Irish and Welsh. As for Scots, it's in the same dialect continuum as English, and isn't a Celtic language at all. It's a Germanic language that is very closely related to English. Ever read the novel Trainspotting? It's written in a mixture of standard English and Scots. As for samples, here's the start of the Lord's prayer. In Irish: > Ár n-Athair atá ar neamh, > Go naofar d'ainim, In Welsh: > Ein Tad yn y nefoedd, > sancteiddier dy enw; In Scots Gaelic: > Ar n-Athair a tha air nèamh, > gu naomhaichear d'ainm. And in the Scots Language: > Oor Faither wha bides in heiven, > Hallowt be thy name;
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Does taking a shower after sun exposure reduce the amount of radiation on your skin(and possibly decreasing the intensity of a sun burn)?
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> How exactly does solar radiation interact with skin cells? Energetic photons (i.e., UV light) can cause chemical bonds to break, or excite electrons to a more energetic level, thus making bond breakage and formation more likely. [DNA can be damaged in this manner](_URL_1_) by forming bonds where they're not supposed to. This can be repaired, or if the damage is too severe, the cell undergoes [apoptosis](_URL_0_). If these regulation mechanisms fail, cancer may result. Notice that the damaging part occurs only when there is UV light. As soon as that is removed, there is no further damage that could be done by that mechanism.
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Well, the colour of your skin depends on how much melanin pigment you have in it. When you expose skin to UV light, two things happen: One, your cells start creating more melanin in response to the exposure, and two, some of the melanin that was stored in the lower layers of your skin gets moved up into the upper layers, which results in a darker tone of skin that you get a day or two after tanning. It's been shown that the latter response plays a bigger role in how dark your skin actually looks, so maybe if we could trigger this response with some chemical rather than UV light, it could be possible. [Source](_URL_0_)
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Why does a laptop/PC need a fan but a tablet does not?
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CPUs draw power. **All of that power** must be radiated as heat. Hopefully, you're not *really* 5 years old and still remember incandescent light bulbs so you have some idea how hot a 100 watt or 60W bulb is. A typical desktop CPU draws between 60W and 150W of power. A typical high-powered laptop CPU is around 50W and a low-powered CPU is 15-30W. A typical phone/tablet CPU is going to be 5W or less. The phone/tablet CPU is running low enough power that it can passively radiate heat away through the case. The more power-hungry CPUs in desktops and laptops need fans to move cool air across the heatsink to do this.
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Off the top of my head, there's usually three things in a computer that makes noise: - The 'oldschool' but still very popular hard drive that works like a record player by spinning. - A CD-ROM drive that also spins. There's obviously not one on the iPad. - The fan that spins to cool down the computer. When your computer is busy a lot for a long period of time it actually makes a bunch of heat. A tablet computer has greatly lowered expectations for memory (so they can do away with using an oldschool harddrive) and performance (so they can get away without a big loud fan). Also, like any controlled product, because of the lowered expectations and total control over the production, Apple can do specific optimization to reduce noise and temperature too.
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Unions, why were they created, what do they do, how do they work, etc.
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I won't repeat what others said but I will say I find it interesting how so many people have been duped into believing unions are bad. This is my first union job and thanks to the union my benefits weren't cut nearly as bad (vacation time was cut and retirement but health and dental are the same) and I've been able to get a raise each year verses once in 5 years that management gets. Unions are mostly good. (Not perfect, but mostly good). Shitty businesses fear them because they know they'll force the business to treat the employees better. When I worked at a Circuit City many moons ago if you even mentioned a union you were to be fired on the spot and escorted from the building.
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Imagine if you walk up to your boss and say "I want to be paid more, or I'll stop working". The end result here is that your boss probably fires you. Now imagine you get all your coworkers, every single one, to go up as one group and say "We want to be paid more, or we'll stop working". Your boss can't just fire his entire staff, so he'll have to negotiate. That's the purpose of a union, to gather enough employees together that simply firing them and hiring new ones aren't worth it, thus giving power to employees.
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Why did animals like sharks, crocodiles and roaches "stop evolving"?
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Richard Dawkins explaines this in his book "Climbing Mount Improbable". Quickly explained, evolution works by favouring mutations that allow the fitness of that organism to increase, but not decrease. The maths behind the possibilities of mutations lead to an area with a plethora of local maxima. The animals you mention have reached one of their local maxima, and thus every mutation will most likely be a step down from there. So every roach that is born with a mutation will be less fit than it's brother (or sister) that hasn't that mutation. Now, in the very very (indeed very very) unlikely event that multiple mutations occur in an individual, that will let the roach jump from one local maxima to another, this will give that organism the chance to further improve its fitness. Until that time, it will look like evolution has stopped. However, it will never have truly stopped.
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Evolution does not evolve animals to suit their environment. Evolution is random. Evolved traits which happen to be more suited to an environment let the animal breed more or faster and propagate the useful genes.
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How are cars, computers, and other electronics/equipment able to keep up with current time when turned off?
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The components that actually do the time keeping aren't turned off, but run on batter power until the device is switched back on.
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They have an internal clock, a lot like a wristwatch. It keeps track of the time. There's even a small battery on the motherboard to keep track when the computer is unplugged.
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How can polar or tropical animals live in ZOOs with completely different climate than they are accustomed to?
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Many locations around the world actually experience extremes of temperature and weather that fit in with a temperate climate, for instance northern Siberia experienced a heat wave of 32C. So most animals are adapted to temperatures outside what you might expect. In addition small animals like lizards are provided with heat lamps and other features to make their areas more suitable alternatively polar bears are given pools to swim in to shed some excess heat.
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Because we have adapted for adaptability and not specialization. This has allowed us to live in far more climates than most other animals.
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How is a full moon possible when the sun always hits it from an angle off axis of the Earth?
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The Moon's orbit is actually on a slight tilt of 5.14 degrees from the plane on which Earth orbits the Sun. Usually, during a full moon, you can see the Moon from the light reaching it either above or below the Earth. On the odd occasion when the Moon actually lines up with Earth's orbit and passes through its shadow, you get a lunar eclipse.
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The moon probably used to rotate more independently, but the gravity of earth has tidally locked it so that it only rotates once per revolution. The Earth could become tidally locked to the moon, but it would take so much time, the sun would burn out before that happened. It's also mostly referred to as the far side of the moon because it's not dark. The sun hits it, we just never see it from Earth.
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Why do we have to vomit when we smell something very unpleasant?
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Probably an evolutionary advantage. Some of the smells more unpleasant to us are linked to poison or unhealthy food (like rotten). If you start smelling something unpleasant, there is a higher than usual chance you may have eaten something recently that is poisonous. A quick purge may help you survive. Now, this system is far from perfect, there are plenty of unpleasant smells that bear no risks and some odourless dangerous stuff, but in general, it was probably good enough for natural selection to consider it a positive trait.
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Usually if an animal was to encounter something which smelled very bad it was also likely harmful for them to ingest it. Throwing up what they ingested was likely to prevent them from experiencing even worse effects if they tried to digest whatever foul thing they ate. Instincts like this address animals being incredibly stupid. "Oh, smells like shit... better eat it anyway!" The reflex would fix what they weren't smart enough to avoid. This is also why smelling people's vomit tends to make other people throw up: If one member of the group got sick from something they ate then probably others ate the same thing and need to purge it too.
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How accurate are our measurements about the size of the universe, the distance to the sun, etc?
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How accurate is a tricky phrase in science. Nothing is known perfectly, the precision is defined by the size of the 'error bars' or 'uncertainties'. Wiki quotes the age of the universe as 13.75 +/- 0.11 billion years. That 0.11 isn't vague, it is a well defined and rigorously considered number, there is no other statement of accuracy.
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No one has ever made any serious claims as to the size of the entire universe (as in, everything that exists), but I think the common assumption is that it is infinite. However, what you may have seen is the size of the observable universe, which we can estimate with accurate knowledge of the energy content, and thus expansion history, of the observable universe.
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Can the manner in which you ask for a lawyer be used against you in court?
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Yes but that situation would help the prosecutor very marginally if any at all. You could probably claim extreme emotional duress because if you're yelling that you want your lawyer then you're most likely in the process of being lead away in handcuffs. The opposing counsel isn't going to delve deep into this particular instance unless your emotional behavior was met with something like resisting arrest or acting violently and your mental status was a key aspect to the case. If the person yelling had no prior record then it's likely that this isolated situation won't even be brought up.
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I've read in SPQR by Mary Beard that you actually were not legally permitted to pay a lawyer directly. In practice, for example, a famous lawyer like Cicero, would accumulate favours from rich citizens he represented. So if you had no promise to later be able to do a favour, it might be difficult to find a decent lawyer to take the case. Cicero for example would buy various properties for low prices as compensation for representation. But as for what a poor person could do for representation, I don't know.
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Why can't gigantic strongmen like the guy that plays The Mountain on Game of Thrones make it in the NFL?
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Speed and technique. Even the fattest overweight nfl player could beat you in a race.
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The same reason you can push over an anorexic teen easily, but would have trouble with a wwe wrestler. Because they are gigantic. The USS Ronald Reagan, a Nimitz class Aircraft Carrier, may look unstable, but remember that it is displacing 100'000 tons of water.
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Why is Newton's Second Law Unecessary?
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You have it the wrong way round, the *first* law is unnecessary as it's just a special case of the second law - if you substitute in F=0 you can conclude that a=0 as well (since it doesn't make sense to have m 0). Therefore, if an object is not acted on by a force then there will be no acceleration, which is Newton's first law.
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> where Energy is required in order to make Force You're trying to put a square peg into a round hole here. You shouldn't equate mass in those two equations because the energy in the first represents the rest energy of the mass which has nothing to do with it's motion. That E, energy, literally has nothing to do with newton's second law. A system can *have* energy or it can transfer energy to change the system. For instance, there is the force of gravity acting on a rock sitting on the ground, but the system is unchanging, therefore no energy is transferred around, though the system could have an intrinsic potential energy. If you have a force, there's some energy associated with it (Though ***not*** how you put it!), but not all situations with energy have forces. Two baseballs flying away from each other (ignoring gravity) will have no forces between them, but they will have an energy, in fact they'll have a mass too that isn't just the sum of their two masses, but that's another story.
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How come being intoxicated seems to make most people act idiotic, while some are more enlightened and thoughtfully provoked?
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some people are simply too uptight to function at 100% and need to relax a bit before they can shine. There is a theory in bar gaming (pool, darts, shuffleboard, etc) where most people get better after 1-2 drinks because they stop worrying about what they are doing and just doing it (just like athletes can choke up if they think about what they are doing too hard). However, any drinks after that and the negative effects start to kick in (lack of coordination, impaired thinking, etc).
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People tend to act based on their expectations, not necessarily the reality. There is a pervasive story that tequilla has particularly potent effects, so when people drink it, they enact these expectations. They are also more likely to notice and remember activities which fit into this preconception and then relate them together to other people. It isn't impossible that different alcohols have trace chemicals which have some impact, but the strength of these influences is slight compared to the social preconditioning.
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Bizarre parking lot?
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It's an attendant operated lot. This is the optimal arrangement from a revenue perspective for high-volume, dense areas. You make more money by having more cars in the lot than you lose by having to pay someone to reposition cars.
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Most likely the third floor promenade, outside the Sun Room [_URL_0_](_URL_0_)
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Why is fraud a crime but being a 'psychic' not a crime
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They generally get around fraud law by using phrases such as 'for entertainment purposes only'. While they're clearly presenting the image that they can talk to dead people, or find missing persons, they cover themselves with legal technicalities.
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That is because the person who gets their money stolen from the bank account isn't the victim, he's the middle man. It doesn't work the way you imagine. What happens is that they steal money from a bank account A and then scam the bank-account-owner B by getting him to receive money and forward insecurely to C. Guy A gets the fraud reversed and his money back because its all traceable. Guy B is fucked. source: _URL_0_
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Why are men so into lesbian porn, while women usually aren't into gay porn?
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Women tend to fantasize about experiencing what they see. Men use what they see to create their own fantasy. Women can't imagine themselves having gay sex. Guys can fantasize about the hot chicks without putting themselves in the "shoes" of the performers.
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we imagine that we are the guy fucking her. lesbian porn is hot too.
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What's the deal with "morning wood?"
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Its called nocturnal penile tumescence. Basically, when a man without erectile dysfunction sleeps, he goes through roughly 5 erections that last around 25 minutes. Its sort of a way to keep everything working well, like an exercise program if its not being used during the day. If you happen to wake up during one of the cycles, bam! Morning wood
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Morning wood - and spontaneous erections in general - are a form of maintenance on the penis. The erectile tissue in the penis stiffens if not stretched regularly, so high testosterone levels in the body trigger it to stretch itself out periodically in order to stay limber. As a transgender woman, I take drugs that block testosterone - and as a result, no longer get them. If I didn't use my penis for a while (a few months), erections would become very difficult and painful.
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Why don't they arrest the people in rehab or Narcotics Anonymous meetings?
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You need to be in possession of drugs to be arrested for them. Just because you did some drugs doesn't make you a criminal or there being a crime to arrest you for.
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Jailing addicts doesn't actually do anything for them. Being in prison doesn't make them want to use less, and usually they will go back to using once they get out. Except now they have no community, money, and likely cant find a job. By decriminalizing you can bring the market out of the shadow and into the light, where it can be monitored and controlled. You can do things like set up clean needle dispensaries and places they can get their drugs checked for impurities. This essentially gives addicts a safe place to get high around medical staff instead of ODing in a bathroom somewhere. You can then take all that money that you spend on funding drug policing and put it into state sponsored rehab programs and mental health therapy instead. Addicts have problems outside of being an addict, and as long as those problems persist they are going to keep on using. Throwing them into jail just adds more problems and results in them being fearful of looking for help when they actually want it.
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Why does itchy skin turn brown when being scratched too much?
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Whaaaaah? My skin is always brown. I've never heard of this. Its like reverse ashy!!
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Scratching irritates the skin. Often our hands are unclean, thus scratching brings in more germs to an area, while also exposing newer skin to the surface. Scratching also feels good (providing a sense of relief). To answer your question (Citing Wikipedia): *"Referred itch or Mitempfindung, is the phenomenon in which a stimulus applied in one region of the body is felt as an itch or irritation in a different part of the body".* Statistics show, that on average, 1 in 5 people exhibit the behaviour - itch one place, scratch there, which causes another itch somewhere else, cycle continues a couple of times.
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why do you feel it so much stronger when other people touch you as opposed to yourself?
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Your brain has a "sense" that let's it know where parts of your body are, for obvious reasons this is useful. When you go to touch your left arm with your right hand your brain knows their relative positions and so you "know" it's you touching you and you "feel" it differently. As for why the actual feeling is different I'm unsure, hopefully someone more knowledgeable can jump in but I'd wager it's evolutionarily advantageous to be able to distinguish between your own skin contacting itself vs something potentially dangerous touching you. To elaborate, you want to be able to quickly react to something foreign touching you in case its dangerous but you don't want to be hyper aware every time you touch yourself.
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Just like hunger, it helped us survive in the past. Our body rewards us for doing something that is helpful to survival. Just like eating salty, sweet, and fatty foods feels good, or sex feeling good. Touching reinforces social bonds, and it's a way of showing trust without words. No matter if it's a parent & child, your fellow cavemen living in close quarters, or your friend with a spear that has your back as a sabertooth cat circles you. You might be a caveman that has no formal language, but touching gets the point across that you are a friend.
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Could a blurry photograph be "sharpened" by using additional information?
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Yes. Motion-induced blur specifically can be compensated for significantly if there is sensor data available about the motion that created the blur. And even if there's not, you can do analysis on the image and get a good guess, then try to clean it up.
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I'd say it's more representational than physically accurate, but it's close. If I take off my glasses, I have to get close enough to see the corrected image they produce. In my case I have to get within about 4 inches away. When I do that the image in the glasses is in focus, but it looks like a fish-eye lens image. The background is blurry like that. I expect this image is really two images, one in focus to replace the lenses of the glasses in Photoshop or some other imaging software, and the other of the bricks out of focus.
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How do lifelong politicians, (for example Dianne Feinstein, John Kerry, John McCain, etc) have net worths of tens or hundreds of millions of dollars?
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In the specific cases you've mentioned, they all married very wealthy people. However, a lot of high ranking politicians were already very wealthy before they ever decided to run for office in the first place.
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> selling for ...more than they are worth Can you clarify this? How do you know they are not worth what other people are willing to pay?
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Different types of assets: shares, bonds, options, funds and derivatives
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- Share = 1 vote for a company's big choices. 5 shares = 5 votes, etc. - Bond = IOU - Option = "You'll sell or buy me something if I decide I want it. I need to find out some other stuff first. Here's some money for agreeing to all of this" - or you could be the person agreeing to do the deal. - Fund = "Let's all give our money to an expert in buying gold (or whatever) at the right times. They'll get a better deal because they buy so much of it." - Derivates = "Well, if we call it investment insurance, insurance laws will have to apply. Let's just set up agreements for deals to take place in case something bad happens and call the agreements derivatives."
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Assets. They own property and stock in other companies. Cash is pretty much the worst place to store money.
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why does illegal money need to be "laundered"?
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Because people have to pay taxes, and the government would notice huge amounts of money appearing from nowhere. Let's say that you are a drug dealer. You make cash money, and you buy a big house and a car. But, you don't pay any taxes. The IRS sees all of the sales records (the person that sold you the house files taxes, the dealership that sold you the car, etc.) and says "That's odd, this guy isn't reporting his income!" And then they investigate, and find out that you have all this illegal income, and you get arrested for not paying taxes, and then that gives them cause to look into everything else you have been doing. Let's say, however, that you own a carwash. You get money coming in from that. But, you also have money coming in from your drug business. So, you make it *look* like the drug money was actually from cars in your car wash. The IRS looks at it and says "what a successful car wash," stamps your form, and you're good to go. It disguises the illegitimate money to look legitimate.
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Because they avoid the local regulations that might easily track where the money came from and who it is going to. Large movements of money say between the USA and Columbia might attract the attention of authorities suspecting that it might be drugs related. However if the money is moved from the USA to the Cayman islands and then from an account in the Cayman islands to another account in the Cayman islands and then to Columbia it becomes impossible to track where the money is going without the cooperation of the authorities in the Cayman islands.
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How can an ice cube become red hot and even catch fire without melting via induction heating?
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The cube has a piece of metal frozen inside. The coils create an alternating magnetic field that induces a current in the metal; it effectively "shakes" the atoms which results in heating. So this demonstration shows how the magnetic field penetrates the ice block and heats the metal red hot, melting the block from within.
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This video really needs a better description. What you're looking at is an induction heater, which is heating a piece of metal frozen inside the block of ice. The metal gets red hot very quickly, so the ice hasn't had time to melt before the metal starts to glow.
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How to polish a calcite crystal for optical transparency?
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Opacity is usually (haven't seen your specific X-tal) due to zones rich in inclusions and crystal defects. No amount of polishing is going to make those transparent. Otherwise, it is best to start with a [good quality "Iceland Spar" variety](_URL_0_) and just cleave platelets out of it with gemcutter tools or a razor blade. They are relatively cheap and easy to come by. Using sub-par material will just be a waste of time and resources. That being said calcite is really soft so normal polishing materials (say emery) would be way too abrasive. If you were really gung-ho on polishing, I'd advise using a well sorted lime-mud suspension.
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Quartz crystals when pretty much perfect are nearly transparent. They are translucent most of the time though. crystals form by repeating patterns. In quartz its silicon dioxide, when you have impurities or changes to the crystals it alters the physical structure and causes a change in characteristics. So the change in transparency most likely is caused by some disruption whether contaminants or physical shock.
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Why was Algeria made an integral part of France in 1848 and not, like Tunisia and Morocco, a protectorate?
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Algeria was the first country in North Africa France colonized. That colonization has its origins in a diplomatical incident, added to issues of piracy by the regency of Algier, as well as the fact that France was indebted to the country. As for the context, France was also looking for some prestigious endeavour, so the incident came right on time for a nice victory for the French king. This led to a war between the regency and France, that France won. So basically, since France won the control of the country by way of conquest, its grip on the country was very strong, whereas in Morocco and Tunis, it was more of a progressive submission and incursion into the state. Also Morocco was more coveted by other countries, which recquired a more subtle approach by France. This allowed a policy of french settlement in Algeria, and a far closer integration in the French state.
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Hi there! While you wait for an answer, you may be interested in these older threads about French Algeria: _URL_0_ _URL_1_
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How can there be WiFi on an airplane?
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The earlier systems, like Boeing's Conexxion, used a special kind of antenna called a phased-array antenna. That antenna sent radio signals to a satellite in orbit which was then sent back to earth to an ISP. Slow, but it kind of worked. You also needed an antenna dome added to the top of the plane. The newer systems, like Gogo, use cellular transmitters on the plane to talk to special towers on the ground. The towers are just like your 3G/4G towers but the signals point UP instead of down at the ground around them. Gogo is planning to add satellite transmitters later so they can handle overseas flights. Once the signal gets to the plane it's sent to a normal wifi access point and access/billing is handled at the ISP.
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Nothing. It's just that they want to minimize any potential risk of interference from 100+ cell phones on the plane. Even then, most of the electronics of the airplane are pretty well shielded against things like that.
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How do the brains of very small humans function at the same level of a brain of average size?
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You seem to be under the impression that brain size is related to intelligence. It is not. Total neural connections between brain cells and between brain regions is related to intelligence. This is why elephants and blue whales are not smarter than humans.
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Mostly it does. For example men in general have bigger heads than women and also bigger brains. Of course there is some variation in the thickness of skull and skin. The size of the brain also decreases as you get older. There is however not known correlation between the size of the brain and intellect.
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Hello Askscience, I'm wondering if gasoline (petrol) has explosive potential.
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Gasoline vapors will combust quite readily, however there's no possibility of an explosion from a strictly scientific standpoint unless it is mixed with air and compressed. Like in an internal combustion engine. Otherwise it's just a big fireball.
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No, that's just Hollywood special effects. Mythbusters did an episode on it. The only way you can ignite gasoline with a bullet is if you use an incendiary round or tracer round and even that's very unlikely.
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How can a small country with bad missiles be confident of fighting big countries if it doesn't have people who knows how to occupy and all that it has is its scary missiles?
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The same way players with bad hands at poker battle against Big hands. By bluffing. The problem is that in this game of poker, N.Korea already showed the cards. So bluffing + lying + courage. Also it's not "a small country" it's more like a small person named Kim Jong-Un. 99% of the population there think that N. Korea is a World Power, they are just tricked
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You can't just go around assassinating the leaders of countries you dont like! The international condemnation would be brutal. Even though noone likes Kim Jong-Un, and everyone thinks North Korea is pretty shitty to its citizens, if say the US were to send agents over (and don't think they aren't capable of it) and they got caught.... every country, every world leader would be a potential target. Who's next... Castro? Angela Merkel? Anyways, rumour has it that he's ultra paranoid about exactly that and travels around in tanks and armoured trains that make Limo 1 look like a tonka toy.
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why do babies throw up/spit up so often compared to adults?
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Their gastric lining is super sensitive to stimuli, acidity vs. alcalinity. Also their stomachs are incredibly small, so eating too much too quickly causes vomiting naturally. They have no idea how much food they should actually consume at 1 time so that's why there's so much literature out about how many ounces and how often to feed them.
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It's part of the reflex. The parotid gland squirts a load of watery (serous) saliva into your mouth. This not only lubricates the vomits' path outwards, it also helps to alleviate some of the acidity of your extremely acidic stomach acid to minimise damage. (Dentist answering here btw)
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Does light slow down when traveling through a medium?
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Yes, light does indeed slow down when travelling through medium. The concept that light always and only travels at the speed of light c applies to vacuum. The (phase) velocity of light in a medium with refractive index n is v = c/n. For reference, n ~ 1.5 for most glass, and 1.33 for water. So light travels about 0.66c in glass, and 0.75c in water.
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Yes, but when going through a medium photons are being absorbed and retransmitted. This causes the apparent slowdown.
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Why are there so many unexploded WW2 bombs? Why were these bombs so inefficient?
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It isn't that the bombs were particularly prone to malfunction, it is just that there were **so many** bombs dropped in total. The Allied forces dropped 3.4 million tons of bombs between 1939 and 1945. London had more than a million kilograms of bombs dropped on it within 24 hours! With all those bombs something will go wrong eventually.
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It was called [Operation Downfall](_URL_0_). They didn't have more bombs immediately available, but orders were made to have 7 more Fat Man-like plutonium bombs available before the operation began for use against the Japanese. The plans called for a 48hr delay period between bombing an area and sending in American soldiers, which would have been disastrous because that would've resulted in a lot of radiation exposure for allied troops.
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does shaving your legs for cycling have a noticeable difference for an average cyclists, or will have it only have a noticeable impact for professionals?
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There's a misconception that cyclists shaving their legs is for aerodynamics. Those gains are minimal. The big reason is so when (not if - when) you get road rash, it heals much faster and with less chance of infection. Source: used to be a Cat III cyclist.
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I'm mostly familiar with the benefits for competitive cyclists, so I'll explain why they do it. 1. Whenever they crash, the road rash heals much more quickly and has a lower chance of getting infected. There aren't hair follicles ripped out that would have to heal along with the skin, and hair follicles also take longer to heal. 2. [Video detailing aerodynamic benefits](_URL_0_) this video, done by Specialized, shows them running athletes in their wind tunnel with and without shaved legs and comparing the difference in drag. For an average person riding at that speed, they could save between 1-2 minutes per 40 kilometers which is huge for pros and racers. 3. Finally, there's also the facts that everyone has done it for a while and that, as a cyclist, you generally have good looking legs anyways and can show off lol. Hope that helps!
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Please explain irony to me (LI5).
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Irony would be like making a post in a forum designed to give you answers to common questions, and having someone type out a long sentence and make you read the whole thing but not even answer your original question.
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Irony has to be the opposite of what you'd expect. Coincidence just means two unlikely things happen without correlation.
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How can people tell when someone is staring at them?
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They can't. You just have a recall bias, because you remember all the times you looked around and made eye contact with somebody looking at you, and you don't remember all the times you looked around and nobody was looking. Because those instances are mundane. This has been asked a thousand times on this sub. Please search next time.
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asking the *really* important questions! i think they are looking for a "unmasked" or unscented location to mark. and the eye contact i think comes from more of a curiosity at why you are watching them.
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Why can some countries decide who can and cannot have nuclear weapons, or use nuclear technology?
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[Because there is a big treaty that most countries signed that says "We won't try to get nuclear weapons"](_URL_0_). It was done after some countries (US, China, Russia, UK, and France) already had them.
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The first handful of nations to develop nuclear arsenals (US, UK, USSR/Russia, France, China) formed a de facto "nuclear club" that has for many decades tried to ensure that nobody *else* gets nuclear weapons- although there have been exceptions, such as the US tacitly allowing Israel to do so and the USSR helping China's nuclear program in the 1950's. It isn't necessarily because the nuclear club are dicks, either, but rather because nuclear weapons programs tend to motivate *other* states to do the same (such as India and Pakistan.) So the point to limit all further nuclearization to reduce the overall risk nuclear war.
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Why do our eyes water when we yawn?
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Your lacrimal (tear-making) glands are on the upper-outer edge of your eye. When you yawn, your eyes close and the pressure squeezes tears out.
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Not 100% sure if this is the correct answer, but the act of yawning presses against the glands which produce tears. These glands are like a sac, so pressing against these sacs make the tear flow regardless of if you need it or not
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Why is ISIS targeting Saudi Arabia, the Shi'ites and/or Sunnis?
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ISIS doesn't really have a side in the Shi'ite/Sunni conflict. Their theology leans Sunni, but they're so radical in almost every way that they are perfectly willing to kill other Sunnis for disagreeing with them in any way. ISIS hates anything that isn't ISIS.
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The justification is religious, but they're also deliberately trying to stoke outrage in order to provoke a response from other countries. The more the West hits at them the more they can claim to be protecting Islam from godless foreigners, increasing their support. Also every foreign airstrike that goes off target and hits civilians is a powerful recruiting tool.
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Can optogenetics be applied to halting cancer?
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Good question and your thinking is correct, but unfortunately on/off only works for electrical signals. This is because optogenetics relies on the use of the light-sensitive proteins, as you mentioned. What's important though is that these proteins are actually ion channels. Since the brain uses ions to propagate electrical currents, closing or opening the channelrhodopsin can halt a signal or cause a signal to be made. So, I'm not sure how you could make optogenetics apply to cancer at all. We already have ways to turn genes on or off via genetic engineering techniques (i.e (CRISPRs)[_URL_0_], (Cre-Lox system)[_URL_1_], etc). And we can make these systems inducible to be turned on/off with a drug. The problem is that in order for these systems to work, you have to engineer the genome and target specific cells without affecting others. This is why a lot of cancer research is focused on targeted delivery to cancer cells only - so we can mess with the cancer cells but not our healthy cells
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The chemotherapy agents used to treat cancer can, themselves, give rise to other cancers. So... yes.
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How does smoking increases the chance to get cancer?
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Cigarettes contain chemical which like tar which cause mutations in DNA. These mutations may cause the cell to turn cancerous. Tar and these other carcinogens are found in minuscule quantities in the air and are therefore not likely to be harmful unless specifically inhaled while smoking or by inhaling cigarette smoke.
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Your body will only heal itself so much. With 20 years of smoking, you will always be predisposed to numerous disease processes later in life. Head/Neck cancers, lung complications, heart complications, atherosclerosis, diabetes, GERD, the list goes on...
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Why have most land animals evolved to only be able to consume fresh water, when most of the water on Earth is salt water?
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Most land animals spend their entire lives miles and miles away from salt water and never encounter any, so there's not much reason to be able to drink it. Even in areas where salt-water is present, there is usually fresh water available, often closer at hand than salt except for regions right on the seashore.
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Because humans evolved from land animal primates, presumably in Africa, with millions of years on the savannas, forests and brush lands.... not the open ocean. Animals always adapt to their environments - and if you look at that of our early ancestors, salt water wasn't that common.
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Why do you get the feeling you need to puke when you stick your finger deep in your mouth, even though your finger isn't touching anything?
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This is the gag reflex, a.k.a. the "pharyngeal reflex": it's actually the throat closing to prevent something too large from going down and causing a blockage, but sometimes it may also make you want to vomit. You almost certainly are touching something, though. It might be the back of the tongue or the roof of the mouth, especially in the area near the back of the mouth; but if it doesn't feel as if you're touching anything, then it's probably the uvula. This is the weird thing that hangs down at the back of the mouth. This functions partly to help close off the mouth when you swallow so that food doesn't get into your nose, and partly to detect when you're trying to swallow something that you might choke on.
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The skin inside your mouth is what's called **mucous membrane**. It's less dense than normal skin, and secretes mucous steadily. It does not have the pruny reflex that some of your external skin has.
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Why is imgur the 'default' image hosting for reddit?
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Imgur was designed by Alan Schaaf in 2009 as a gift to reddit users who complained about other image hosting sites being rubbish. The reason its still used very often amongst reddit users is that its most likely what users are most familiar with, and to be fair its easy to use and "doesn't suck" more [here.](_URL_0_)
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Imgur was literally made by a guy who wanted to make sharing images on reddit easier. Other photosharing sites (photobucket etc) were bulky and not up to the amount of traffic reddit provided.
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Would we still have the urge to breathe if air was exchanged through some sort of IV?
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Probably not. When you hold your breath, the [urge to breathe](_URL_1_) again comes from a buildup of CO2 in your bloodstream. Our theoretical gas exchanger would be removing CO2 as well as pumping O2 back in, so the pain of asphyxiation and subsequent urge to breathe would never set in.
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No; rather, the breathing reflex or instinct is [driven by CO2 accumulation](_URL_0_).
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the difference between technocracy and meritocracy
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They're quite similar. All Technocracies are Meritocracies, but not all Meritocracies are Technocracies. For an ELI5 explanation, a Technocracy occurs when the HIGHEST offices are held by unelected individuals with special skills. [Italy from 2011-2013 is a good example.](_URL_1_) A Meritocracy is more so having a highly skilled and qualified bureaucracy. For example, having qualified scientists in the Department of Energy, qualified teachers in the Department of Education, etc. The aesthesis of a Meritocracy would be filling bureaucratic positions with unqualified people, usually done as a political favor. [Andrew Jackson is infamous for the Spoils System, the aesthesis of a Meritocracy](_URL_0_)
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A technocracy is a system of government where leaders are selected based on their knowledge of technology. A technocracy would be run by scientists and engineers instead of lawyers and businesspeople. A common criticism of this form of government is that technocrats have less understanding of people than lawyers or businesspeople, which would be very harmful for a leader that has to persuade others to accept their idea, consider the consequences of their actions everyone living in their country, and communicate effectively with their citizens.
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Do we know the location of Pangaea relative to the earth's axis?
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To add to sciencedthatshit's comment, [this](_URL_0_) (Reeves et al., 2010) is considered to be the best representation of the opening of the Atlantic and the break up of Pangea. You can trace the continents to where they were based upon the hot spot tracks, and from the asimuth of the spreading centers and transforms.
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Pangaea definitely had some large mountain ranges that formed as a result of its assembly. In particular, the Appalachian mountains are relics of that continental collision. They're not much to look at now because they've been weathered away, but at the time they were huge. [_URL_0_](_URL_1_)
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Pluto's orbit and the plane of the ecliptic i.e. the nasty details of orbital mechanics
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> This means that when Pluto is nearest the Sun, it is at its farthest **above** the plane of the Solar System I'm pretty sure what you're thinking is correct. As far as I can tell, by above they mean 'in the direction the Sun's rotational angular momentum vector points.' So at aphelion (where Pluto is farther from the Sun and the ecliptic plane) Pluto would be below the plane. In that paragraph, they're just caring about perihelion to show that when it's radial distance is comparable to Neptune's, they still don't interact too much since Pluto is so far out of the ecliptic.
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It is not so unusual, Pluto is not special. There are tons of other dwarf planets out there with orbits like this. They are so far away from the sun and they are so small their orbits can be highly elliptical. Interactions with Neptun can influence them aswell. [This](_URL_0_) is what I call an unusual orbit.
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Is it possible for a planet to have inconsistent seasons. Like the Irregular Summers and winters in the book series A Song of Ice and Fire?
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I'm a ASOIAF fan and I was mulling over this question the other day. As was said elsewhere in the thread, it might be justifiable to say eccentric orbits. But within ASOIAF lore, even this doesn't hold up. Seasons are irregular, meaning some winters are much longer than others, and the summers are just as long as the winters. You have the same problem with this irregularity when considering axis tilt as well. So I came up with two other possibilities: one is a binary star system. You can have some strange orbits in a binary star system that could explain the irregular seasons, but I don't remember ever seeing two stars mentioned in the story. Another possibility is that other planets are affecting its orbit, pushing and pulling on it and constantly shifting its path and spin.
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Seasons come about from the tilt of the Earth and it's orientation to Sol during it's orbit. This is why in North America, we're celebrating Winter right now while Australia is celebrating Summer. The Northern hemisphere is receiving less light than the Southern hemisphere. The same thing happens on Mars. However, season lengths vary from Earth's seasons. Mars has a longer year than Earth does, and it's tilt is different than from Earth. Because of this, one of its seasons lasts about 7 months (Spring for the north, Autumn for the south). The moon, however, has nearly a negligible tilt -- about 1.5*. On the moon, it's eternally one season. However, other moons, such as the moons of Jupiter and Saturn, are trickier. They orbit their respective parent planet...and they get lost behind their parent planet during their orbit. So the seasons of those moons are a bit...eccentric, to say the least.
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Why are Europeans dinner tables rectangular while Chinese dinner tables are round?
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Where did you get this idea ? I've never heard that. And I've never got the impression that round tables weren't common in Europe.
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There are a number of reasons: dining room tables are typically nicer/fancier and everyday use would cause more wear/damage to the nice furniture; dining room tables are often larger and wider to accommodate guests, serving bowls, centerpieces, etc. for dinner parties and holidays, but would be less ideal for a smaller group of 3-4 people as they eat casually; it's more convenient to serve and clear from a table that's in the kitchen than to carry all the plates, serving bowls, etc. to another room. The reasons are similar to the reasons why many American homes have family rooms and formal living rooms, too.
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Why are older, smaller houses more expensive toward the downtown core than bigger, newer houses in the suburbs?
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This is not true in all cities. If the downtown is an attractive are then this increases the prices of all houses in the area. It's nice to be able to walk to the businesses down town. Also, many people like me enjoy the aesthetics and build-quality of houses built around the beginning of the 20th century. Size isn't everything.
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People used to live closer to the city centers. Automobiles became popular. People with money could afford to live further away because they were wealthy or middle-class and could afford the suburb housing and automobiles, so they drove further to get to work. The people still inside the city proper are left with poorer housing and neighborhoods where the affluent people have left. Think about what "most dense" means. Highest population per area. The wealthier you are the more area you can afford. Wealthy mansions are the "least dense" areas (other than places nobody lives). The rich don't want their houses to be "most crossed".
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Because interest rates exist everywhere, doesn't that mean that there will come a time when there is much more debt than actual currency in the world?
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This has already happened, and is one of the reasons why the idea that a country needs a 'balanced budget' is antiquated and ridiculous. Large national debts used to be more of a concern because the political climate was much more volatile than today. A coup might lead to a new political leadership that would refuse to honor the debts of the old one. Modern governments in developed nations are extraordinarily more stable today than ever before. This gives creditors confidence that a country can continue to service its debts basically indefinitely, and is why national debts in developed countries will continue to climb. Is there an end in sight? Right now I don't really see a reason for it unless there is some unprecedented natural disaster that totally turns the order of the world on its head.
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It's pretty easy to create debt, because each dollar can be lent out more than once, and used more than once to pay back a debt. Say you're at a restaurant: between when you order and when you pay, there's a debt owed to the restaurant. Meanwhile, their servers work today, but get paid tomorrow - there's another debt. You pay by credit card, which satisfies your debt to the restaurant, but creates a debt from you to your bank, and the bank to the restaurant. Eventually, you pay the bank, the bank pays the restaurant, and the restaurant pays its servers, but there's a lot more debt than money in that whole series.
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Why do ants carry dead ants back to the nest?
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Ants don't really have any understanding of why they are doing certain things, they're pretty much programmed to operate based on certain stimuli. Why did a fellow ant die? infected with a parasite? contagious bacteria or fungus? If the dead or dying ant is taken away from the next or where the colony is active, the lower the chance of it spreading the disease to it's nest mates. For example this is a video of parasitic fungus attacking ants. _URL_1_ For fun, look up some of the [theories](_URL_0_) of why humans like Chanel #5, and a brain parasite.
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Basically they have to discover it, once it has been discovered the message is passed back and the colony sends out a great many ants to harvest the resource.
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When and why did most U.S. politicans stop growing their facial hair?
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_URL_0_ study linked in other link _URL_1_ page 1136 has the key graph world war 1 and 2 had a pretty major impact on getting a generation of americans to keep a clean shaven look forced on them by the military. for this i'm assuming politicians aren't any different from the normal man. interestingly the safety razor didn't impact this trend (invented 1905)
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[This thread](_URL_0_) has some information bearing on the facial hair question. I cannot help with the questions regarding chest/back hair. Please see the summary provided by /u/yodatsracist. Bottom line is that many natives could grow beards, that some did, some were very sparse and, many plucked/trimmed facial hair as a cultural practice.
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What's the difference between inbreeding and incest? Why is the former socially acceptable and not the latter? And why do royalty from the past get the okay-pass for incest?
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When exactly did inbreeding become socially acceptable? Also I don't think royalty from the past get an okay-pass people still think it's disgusting.
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Until kids go out in the world and meet other people, their best friend is mommy or sister or cousin. Our families are the first people to show us love. It's (hopefully) pure and unconditional. Your little brother didn't want to marry you because you were hot, or because he wanted to have sex with you, or because he was attracted to you. In a child's understanding, you marry the person you love, and for the first part of your life, the people that love you most are your family. It's natural to love them back. The concept of incest as wrong is cultural, but it is taboo in a lot of cultures. It's generally not practiced now because we have science backing up the cultural norm, saying that inbreeding is bad for procreation. On the other hand, since birth control is an option, there are some that don't see anything wrong with two consenting adults having sex, even if they're related. In ancient Egypt, incest was practiced among royalty to maintain the purity of the family line. Check wikipedia. It'll tell you.
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Why are work-hour restrictions controversial in the medical field?
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There are good reasons and bad reasons. A good reason is that some operation take a really long time, and there can be some advantages to having the same people perform the whole thing. There are also bad reasons. One is that "we've always done it that way." It's almost like hazing at a fraternity. The older folks say, "I survived the hazing just fine. There's no reason the young people today can't do the same." Another bad reason is that hospitals can save money overworking young docs. I get the sense that the bad reasons are more common among people objecting to work limits than the good reasons. You could certainly restrict hours except for those very specific cases, but you rarely hear the objectors propose that.
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im not a doctor but i feel like the obvious answer here is that if a hospital has doctors working those kinds of hours its probably because its the only way to make sure there are doctors available 24/7. i mean, they cant just say "sorry everyone, we would like to help you but our doctors already hit their 10 hours for today and the next shift doesnt start for 2 more hours" becoming a doctor is a lot of work and it's not like there is an over abundance of them
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The different coloured circles on carton boxes or packaged snacks
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Those are all the colors used to print the package. If the graphic don't come out right you can check which circle of color didn't print and replace that cartridge.
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They make the cells in circles. It just so happens that the closest *packing order* (this is a neat thing to look up) for circles is hexagons, so the walls deflect. If you get a chance to see a beehive with clear sides, you can see this. The cells on the edges are round where they aren't next to anything.
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Do bears have elbows?
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Yes, bears have elbows- deep inside their massive arms. You can clearly see their elbow joint in this [polar bear skeleton](_URL_0_). All mammals have elbows (and knees) or their limbs would not bend in the middle and that would be awkward and ineffective for locomotion.
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Bears do Source: _URL_0_ There are somethings I wish I didn't know
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How do plants get liquids up through their leaves?
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[Capillary action](_URL_0_) and _URL_1_ Basically, water molecules are attracted to plant material with a force stronger than gravity. The attraction is caused by the same force that causes droplets of water to remain on things (such as cutlery or a porcelain plate) when you take them out of the water.
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Water containing nutrients is pulled up from the roots. If the water did not have anywhere to go, then no more nutrients would be transported. The plant allows 90-95% of the water to evaporate to make room for new water with more nutrients.
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Many of us have heard the anecdote that the Statue of Liberty's exterior is actually untreated copper, which developed a layer of the green patina over time. Did the designers of the monument intend this effect?
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hi! you may be interested in this previous thread [Why would they make the Statue of Liberty out of copper if they knew it would turn green?](_URL_0_)
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It's called patinisation. Which might me completely wrong since I just freehandedly translated from my own language. Metals oxydate (iron and steel rust for example) when the are open to the elements. The air. Oxygen! In certain metals, this forms a layer where oxygen is bonded with the metal. This layer is now inert, meaning it won't change any further. So the underlying material now has a barrier shielding it from the atmosphere, so it won't oxydate any more. This layer is what you see on the statue if liberty. Same as many buildings where they used zinc as roofing material. They turn green naturally. It has a patiné. Preventing this is costly and requires continuus upkeep. Removing it means the layer underneath will do the same, leaving you with a slimmer layer every time you remove it. So let it turn green, it'll last longer
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Why do police officers in certain European countries (UK & France come to mind) not carry firearms?
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I've had a gendarme poke me in the chest with an automatic rifle. Some french police do carry firearms. That said. The US leads the world in random acts of civilian firearm mayhem. From Sandy Hook to Columbine every copper in the vicinity was firarmed to the teeth. Giving the constabulary firearms doesn't seem to reduce the number of people who end up getting shot in any society over time, in fact exactly the opposite is true.
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In some countries (most of the Western world i'd say), there is a police investigating both supposedly corrupt policemen and every event where a policeman had to fire its weapon, even if there was no casualty. In France, they are jokingly called the "Bœuf-carottes" (beef-carrot) because once you're on the grill, they're going to *cook* you for a long time ... which is another way to say that once you're on their radar, they're not going to let you go until they are certain you are innocent. Not every country is as complacent towards its policemen are some US states seem to be.
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Why can I not tickle my self?
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Because your brain expects you to touch yourself. There was an experiment done where people were told to tickle themselves with a robot arm. When the delay between their command and the robot was low, they weren't tickled. But, with a delay as low as a fifth of a second (I believe the number was), the participants *could* tickle themselves.
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Being tickled is actually a form of fear or a panic reaction, and if you're doing it to yourself, then your body knows that theres nothing to fear. you can tickle the roof of your mouth though i read this somewhere, im not sure how correct it is but i've seen it a few places..
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When cut off a tree, do leaves still produce oxygen?
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No, leaves need water and mineral salts to produce oxygen. These substances (called raw sap) are collected through the roots and led to xylem, a conduit that's found throughout the stem. This conduit leads the raw sap from the bottom of the plant to the leaves. If a tree is cut, the xylem is also cut and leaves can't receive the raw sap and produce oxygen.
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If memory serves me correct, the vast majority of our oxygen doesn't actually come from trees, but from photosynthetic organisms in the ocean.
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Why can't you give blood if your body temperature is "too low"? What does "too low" mean?
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A body temperature outside the normal range (either high or low) can be a sign that you're getting sick. Blood donations aren't accepted from anyone with signs of illness, because that could easily transmit infection to the recipients. A few people naturally have a baseline temperature outside the usual range. That doesn't present a health risk. But the blood service can't assess for that; they can't tell the difference between a temp that's outside the range all the time, and a temp that is on variance right now. So, to ensure safety of the blood supply, they always err on the side of caution and tell the person not to donate that day.
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Severe hypothermia can occur at a core body temperature 20 of degrees Celsius, while mild hypothermia can occur at temperatures as high as 35 degrees Celsius. Having a temperature that low causes a severe slow down of metabolism, among other things. Many chemical reactions and organ systems require a fairly warm temperature to sustain the rate needed to keep you alive. Your heart and kidneys slow down, disrupting fluid balances and oxygen transportation in your body. The body requires a fine balance in order to function properly, and even a seemingly small change in body temperature can be life threatening in many instances. [Wikipedia Link](_URL_0_)
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Settling wars with chess
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I'm not a historian, but it seems pretty implausible to me. If I was a king, sure, I might play chess to settle a war. If I won, then I'd win the war without losing any soldiers. But if I lost, I'd just send my army to fight the war anyway.
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No...the initial position in chess is close to the minimum possible legal moves. That is what makes the opening phase of chess interesting, the fact both sides have to compete for development.
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Why are some people faster than others?
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It's just genetics, same thing applies to most people in any subject being "better" than others, that and the environment they were raised in coupled with their desire to achieve.
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Compared to most animals, humans are bipedal. So in the most simplest of terms, we only get power from 2 legs instead of 4 making us slower. At the same time, we only consume half the power allowing us to run for much longer periods of time.
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Why is wine best stored horizontally?
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To keep the inside of the cork wet. If you set it vertically, it will dry out and allow the wine to ruin.
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Only wine where the bottle is closed off with actual cork needs to be stored on its side. The reason is that the cork otherwise dries out and won't seal correctly any more which will make the wine go bad. Modern bottles that are closed off with a screw cap or synthetic cork do not require being stored on their sides.
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How do calculators calculate roots?
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Square roots can be calculated algorithmically, since `C = x^2` is equivalent to solving the equation `x^2 - C = 0` for some positive x. Any algorithm that can find the root of a polynomial of this form will also find the square root. This [Wikipedia article](_URL_0_) outlines multiple methods of computing square roots. For Pi, [this site](_URL_1_) has formulas for calculating the digits of Pi to arbitary precision in any base (2 and 10 being common). I'm sure a quick google search will show that Euler's number e has similar methods for calculating it's digits. If I was going to program a calculator, though, I would use constant variables to hold mathematical constants such as Pi and e, likely as a double. For most practical purposes, that should be enough precision.
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By themselves, they don't mean anything. But if your quadratic equation models some sort of real-world scenario, then the roots refer to something in that scenario. If a quadratic equation is the path of a projectile thrown into the air, then the solutions might tell you where the projectile was launched and where it lands. In this case, the roots would have no imaginary part. But there are real-world situations that can be modelled by a quadratic having complex roots, such as in electricity and quantum mechanics. See [here](_URL_1_) for some examples.
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What causes that temporary back pain people get when laying down after a long day?
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Muscles in your back cramping, most likely. They've been working hard all day to stabilize your body while upright, now they're suddenly no longer being used. Like a runners leg muscles might cramp after finishing a long race.
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This is because if you lie down without a pillow you'll find there's a slight arch in your back. The pillow levels your back out. Try it!
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Why does my hearing diminish when I stretch my body?
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Your hearing diminishes because you are flexing your tensor tympani. This muscle serves to dampen sound. _URL_0_
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When you stretch, you're pulling a lot of the stuff in your neck and jaw into unusual positions. This pulls on some of the inner parts of the ear and closes them off so things sound muffled.
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why do microwaves have turntables?
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The Electromagnetic wave propagation through the material to be heated will be uniformly distributed throughout the material if it is rotated. If the material such as (chunk of chicken) is put in without a turntable, the micro waves will propagate into and out of the chicken with one direction (depending on the RF antenna in the microwave) this will cause hot and cold spots (depends on scattering and various material properties such as permeability and permittivity). As a matter of fact if you wish to most effectively heat your stuff don't center it on the turntable, offset it by a few inches.
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Rotating things in the microwave makes them heat more evenly. Microwaves are standing waves, and so a stationary object will have certain parts always cooking a lot, some parts always cooking not at all, and parts in between. By having the food rotate the areas that cook a lot an not at all are moving with respect to the food.
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What is the origin of the pronunciation "left-tenant" when saying lieutenant? Is it a primarily british pronunciation?
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Hi, not discouraging further contributions here, but there have been a couple of good discussions on this * [Why does the United Kingdom pronounce "lieutenant" as "left-tenant", while the United States pronounces it "loo-tenant"?](_URL_0_) * [Where did the pronunciation "leftenant" used in commonwealth armies come from? And why is the pronunciation "loo-tenant" used in America given the shared linguistic heritage?](_URL_1_)
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FYI, it is always spelled 'lieutenant'. The British 'leftenant' pronunciation is based on an older pronunciation of the word, while the French pronunciation changed to 'lewtenant'.
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The Google File System (2003)
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You need to understand why Google implemented the Google File System, and this was not their first attempt at such a system. Google made its fortune in the search business. And their approach required a huge database. Much larger then could be stored on a single server. But they could not afford huge datacenters of servers either. They had to use cheaper desktop computers, and often old discarded computers at that. So instead of one big database server they had to use lots of old cheap desktop computers that frequently broke down. So they had to implement a way to store and retrieve data on all these computers even when it was expected that computers would crash or corrupt data. If you understand these issues the paper actually does a good job at breaking down the details of the implementation.
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Google has links in a database. A database is a type of storage specifically designed for looking up large amounts of data very quickly. Your hard drive's files are not in a database, they are only referenced in your hard drive's file table, which is essentially just a list of files. So if you try to search for a file, your computer has to iterate over the entire file table to find entries that match your query. There are tools available to index your hard drive in the same way Google does (i.e. in a database) to allow for faster access. These tools will index the files on your hard drive into a database of sorts, allowing you to instantly find any file. They continue to monitor your file system so any changes are recorded in the database. The now-discontinued [Google Desktop](_URL_0_) was one of these tools. Nowadays I use a program called [Everything](_URL_1_) which works very well.
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Are the same chemical properties that make HFCs good refrigerants the same as the ones that make it a strong greenhouse gas?
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Fluorine-carbon bonds, (the FC in HFC) are exceptionally strong and create tough, inert molecules. Those bonds are responsible for HFCs low boiling points and their long life in the atmosphere. I believe HFCs generally have a weak effect on global warming, but they stick around for a such long time that the net effect may be significant.
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The hot air they pump out is negligible in the grand scheme of things. They do, however, use a ton of electricity. If this is sourced from fossil fuels, it'll certainly emit greenhouse gases. In addition, most modern refrigerants won't harm the ozone layer, but they are extremely potent greenhouse gases, thousands of times more potent than CO2, though I imagine this isn't a large effect compared to the CO2 emitted from the power generation.
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How does buying and selling debt work?
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The people who buy the debt normally don't pay the full amount to get it. For example, you get a $1k loan from the bank, you give them the impression that you can't pay for whatever reason. They figure they aren't going to get anything back without a lot of effort. So they sell the debt off to a collector for $100. The collector now works really hard calling you all the time and doing whatever it can, it only needs to get $100 to break even so it might even make a deal with you to forgive half the debt if you pay them immediately and you probably will. So in a way, everyone ends up better then they expected, so this circle continues. Except now banks will be less likely to loan to you (your credit rating is lower now) so they don't get screwed as frequently by you.
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So Person A owes 100 dollars to Person B. I as Person B try to get Person A to pay me, but they keep ignoring me. In time I give up and sell the debt to Person C. In doing so, Person C pays me 10 dollars to own the right to collect the debt from Person A. Now Person B is happy because at least he got 10 dollars out of the deal and isn't completely broke. Person C though still has to make his money and the way he does this is by buying up a lot of debt cheaply (so let's say he's bought 8 other people's debt for 10 bucks each) and thus he really only needs a success rate of 10% to succeed. Also, they tend to be more aggressive in hounding the debtor until they pay their bill off (and sometimes mislead the debtor about their obligation to pay said debt).
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Why is the Earth's moon named The Moon while other planets' moons have actual names?
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Because it was named centuries before we knew that the planets had moons. To discover the moons round other planets we needed to invent the telescope and then realised that there were a lot of moons out there so they needed names to identify them.
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The proper English name for the moon is "the Moon". ([source](_URL_0_)). "Luna" is sometimes used in literature, and is the name of the Roman goddess that was the personified moon to the Romans.
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