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Why do some metal alloys have a lower melting point than their constituent metals?
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Basically, the melting point has to do with the temperature at which the bonds between the atoms are broken, allowing the atoms to flow freely. In some alloys, the structure of the latice in which the atoms are held forces the bond geometries into less efficient bonds... thus, less energy is required to melt the material. Fascinating stuff goes on at the atomic level.
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They have a melting point that is far higher than the point at which the metal is liquid. The composition of the items changes it's chemical properties, including melting points.
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The Duke of Wellington famously declined to use his artillery against Napoleon (as in the person, not his forces) at Waterloo. Was this common for commanders not to directly fire at each other?
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To my own knowledge, I don't know but it would be wasteful to fire on commanders or what is thought to be a commander. Generally, artillery would be fired at formations and general areas due to a combination of poor optics (as in a Spyglass doesn't magnify that greatly to see an exact person) and inaccuracy of guns, which can change due to an innumerable number of reasons. So, when artillery is used, it is used to fire on a general formation or area in order to use accuracy by volume and ensure that the shot isn't wasted. However, whenever a general did die or get injured, it was due to a random shot bouncing across the field. Jean Lannes got his legs swept from under him during Aspern-Essling by a random shot rolling across the field and Massena got his horse shot from under him. This is generally due to the inaccuracy and randomness of the battlefield. I haven't heard an order to avoid or target generals though.
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No they never met face to face. Though they faced each across the battlefield at Waterloo Napoleon fled for Paris after his defeat and eventually surrendered to the British at Rochefort. At no time despite his captivity in British custody did he and Wellington ever meet face to face.
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How do scientists know how many elements there are?
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Each element has a unique number of protons(and electrons), starting with hydrogen at 1 going up to uranium with 92. Beyond uranium the elements become unstable and are usually man made, if they were to somehow be created naturally they decay rapidly into other elements, usually in fractions of a second.
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The element is "defined" by its nucleus, specifically the number of protons you have. The number of neutrons is also very important, especially because if you have the wrong number of neutrons the nucleus will just fall apart very very quickly, but the protons are what defines the element. Once you have a certain number of protons, the atom will "want" to become neutral, which means it wants to have a the same number of electrons as protons. But this isn't always the case: you can have an "ion", which is where an atom has too many or too few electrons. But it's still the same element, because it still has the same number of protons. In fact, when you have fission and fusion reactions, things are usually so hot that many of the electrons have too much energy to properly latch onto atoms, so most of the atoms don't have "enough" electrons: they are ions with lots of positive charge.
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Why do people think it is so bad when machines or robots take over human jobs?
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Because it's hard for the person who has lost their job to think of the bigger picture and the overall effect on the economy when they had such a big thing happen to them. It doesn't matter if their jeans are $24.99 instead of $29.99 when they can't afford to buy jeans at all. It's also much easier for people in general to identify with the person who has lost their job than to think of the abstract concepts of wealth and efficiency. It's simply not how the human brain is wired. We're wired to connect with individuals, not ideas.
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Because reality. "Hey it's over! Wait I still don't have a job and neither do my friends."
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Why is crack-cocaine more addictive than cocaine?
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The faster a drug is absorbed, the stronger the high will be. The drug is absorbed more rapidly via smoking than insufflation. The immediacy paired with the physical act of smoking creates a strong mental connection between the act of consuming the drug and the effects of the drug. Examples of that effect can be seen in people who use eCigs simply for ~~water vapor~~ smoking simulation, or IV addicts who inject water simply for the ritual. The duration is also shorter, leading to taking hits of the drug more often, reinforcing the addiction to the ritual and drug. _URL_0_ > The crucial variables appear to be the immediacy, duration, and magnitude of cocaine's effect, as well as the frequency and amount of cocaine used rather than the form of the cocaine
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Cocaine is water soluble meaning that it can be absorbed very easily into your body. It is also extremely easy to develop a dependency on it to the point where trying it once could get you hooked. Be wary.
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How does a Krasnikov tube work?
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From [Wikipedia](_URL_1_) (emphasis added): "A Krasnikov tube is a **speculative** mechanism" It works exactly the same way as [this time machine](_URL_0_).
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It works by surface tension and molecular adhesion working together. In ELI5 terms, the water "sticks" to a surface a little bit, but it also wants to form into a ball. In a narrow tube, it "sticks" to the sides easily and start to creep up them. But because it wants to form a ball, the middle rises to meet where the sides are sticking to the surface. Acting together, this makes it rise. _URL_0_
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"Chinese Proverb: if you are negotiating and you’re buying, [act as if] you are selling. If you’re selling, [act] as if you are buying.”
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In negotiation, if I know you're desperate to buy, I can deal harder because I know you won't walk. Similarly if I need to sell, a buyer who knows this can low-ball me. I sold a motorcycle once. The guy fell in love with it the moment he saw it. My asking price was a little high, but I was expecting to haggle. This guy told me he didn't want to haggle, and I'd just watched him decide to buy my bike. It was written on his face. So when he asked, "How much?" I gave him the full price I'd put on craigslist. He handed me cash and that was that. edit: I didn't actually answer your question. If I want a good price on your goods, I should pretend I don't need/want it and rope you into the position of changing my mind. You'll end up lowering your price in your efforts to convince me.
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My general rule is if someone is aggressively trying to sell me something, it's a piece of shit. Good products sell themselves on value and merit.
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How does the granulation of baking soda affect its use?
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Food grade baking soda is a finer powder (~70microns) than refrigerator baking soda. The larger grains of refrigerator baking soda may affect the taste of your food if used for cooking - pockets of higher concentration, more difficult to dissolve, etc...
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The answer is it Technically doesnt. Whennpeople say somthing eliminates an odor what they mean is masking it with a different smell. An odor will never go away until the source is cleaned. Sodium bicarbonate (baking soda) is a substance with a low ph or acidity. Many odors that lurk around tend to have higher ph levels. So the baking soda nutralizes the odors by absorbing them. Sorta like how salt absorbs water but the odor is the water.
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Is there any truth to the practice of Acupuncture?
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This is a blog run by Dr's, medical scientists, etc.. check out some of their articles on acupuncture. [Science Based Medicine](_URL_0_)
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There is no sound evidence suggesting that acupuncture works for anything other than as a placebo.
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In Vikings S01E07, the Vikings defeated the Saxons in a battle and were surprised of the quality of British steel. Is that likely?
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Short answer: No chance. Long answer: The Scandinavians had been making relatively high-quality weapons for quite some time by the viking age, not to mention trading with the Franks and Germans (and Romans!) for several centuries before the Lindisfarne raid. Insofar as pottery and ceramics were concerned, the answer is basically the same as for weapons: Of course they did; they'd been making it indigenously and trading for it for centuries. The more I hear about this show, the happier I am that I stopped watching after the first episode.
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The sources we have on viking raids are either, as /u/vhite said, from the victims or from 13th century or later Icelandic accounts. That said, I'm not familiar with any *víkingar* who are mentioned as butchering entire villages and towns. The closest I can think of is Arinbjörn and Egils raid on the Frisians, when they sent the whole village into flight and chased after them. Even then, there's no mention of wholesale slaughter. During the Danish invasion of Britain, that might have happened with the Great Heathen Army, but they were neither *víkingar* nor raiders, and so don't really fall under your question.
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Is there really a infinitesimally small(but still non-zero) chance that I could tunnel through the chair I'm sitting on?
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You run into a fundamentally difficult problem with these kinds of questions, because scientific knowledge is always limited. Once the probability of an event gets low enough, it may become more probable for your theory to be wrong than for the event predicted by it to occur. So when you say "infinitesimal but nonzero", a reasonable answer could simply be "anything is possible because we don't know everything." That seems to be answering a different question, but at the level of accuracy you're requiring, those ideas bleed together. Our understanding of reality doesn't carry enough information to distinguish between the two questions on that level. So, yes, you could (in theory) tunnel through a chair. But you may be just as likely to do anything else (like prove quantum mechanics wrong), since that would be possible in theory as well.
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Electrostatic repulsion. As your hands get closer so do the protons and electrons of your hands, the closer two electrons get to each other the stronger the repulsive force. You sitting in your chair right now is possible because the electrons on your butt (or clothes) are being repelled by the electrons on the chair.
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Why were many early movies westerns and why were other genres relatively slow to develop?
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A) Westerns were extremely cheap to film B) Some of the cowboys were still alive or only recently died when the genre hit its peak, adding a hint of romantic nostalgia. C) The increased availability to foreign markets helped as well, along with people fascinated by america's wild west. You may have heard the term "spaghetti western". They were called this because of the amount of italian companies financing them. Cheap and profitable with a global audience. It's partly why foreigners often think all americans have a "cowboy" attitude.
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It really begins with the explosion in [dime novels](_URL_0_) following the American Civil War. Initially, most of these would've been about [Mountain Men](_URL_2_) or trappers moreso than cowboys, but with rail expansion came an explosion in the livestock trade, so that ranching became the prototypical western occupation. The lawless, frontier nature of the West is a natural breeding place for drama, and the antics of the notable lawmen and outlaws of the late 19th century made for great pulp fiction, further growing the mythology of the old west. [Buffalo Bill's Wild West](_URL_1_) show really capitalized on an interest that already existed, but it played an important part in cementing the Wild West archetypes in American consciousness.
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I was looking at a map of the Los Angeles county with each city outlined. Why are the Los Angeles border lines so f*cked up? Looks like abstract art.
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Don't listen to these people who are saying it's gerrymandering. Gerrymandering has to do with the shape of voting districts, not the shape of cities. See this question on /r/askhistorians for your answer: _URL_0_
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Generally sight lines between boundary markers. Essentially most territories would use natural features (rivers, mountains, etc) to delineate the edges, but if those weren't available, it was common to set up your own markers. Large piles of stone, wooden construction and the like. When then drawing a map, it was best guess. If you look at old maps, you'll notice that the shapes are close, but not quite right. As technology progresses, you could start to take measurements off of the sun and stars to determine latitude (how far north or south you are) and that helped with accuracy, but it wasn't until our equipment got a much greater degree if accuracy in the 1800s that you started to see maps that really were accurate to within a few percent. (A few miles for very large maps.)
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It's c. 1800 and I'm crew on an English man-of-war. What's the bathroom etiquette?
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Hi there, good question (this was asked a week or so ago but was unfortunately part of the April Fool's day, so many of the answers ... smell ... a little). In general, regular sailors and officers would use the heads that were near the head (front) of a ship. Boxes (on larger ships) or holes (on smaller or more rudimentary ships) with seats were provided, from which waste fell directly into the sea. You can see an example of boxes here in [this picture of the Vasa](_URL_1_). Interestingly, "head" is now a generic term for "toilet area" on ships and boats. The captain had his own toilet in a [quarter gallery](_URL_2_) that was accessible from his quarters, which could also be shared with guests, the admiral, etc. In rough weather or in private cabins, sailors, supernumeraries or passengers could also use chamber pots. Lots of sources for this one, but N.A.M. Rodger's [The Wooden World](_URL_0_) is a great overview. edit: removed a couple of words that could have been taken out of context
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I would suggest [episode 62 of our podcast](_URL_0_), which is an episode about hygiene and cleanliness, with a section about the development of modern underwear.
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If a noble, heir-less landowner went missing in Victorian England (~1880s), what would happen to their estate, investments, funds, etc. as a result?
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It would have been handled the same way it is now, under the principle of [bona vacantia](_URL_1_) (ownerless goods). [This](_URL_0_) gives a short overview of the Treasure Solicitors's Department of the UK government ,which was officially founded in 1876. > The Bona Vacantia Division claims to be the oldest part of the Department I'm not sure how your character being missing, and not dead, would affect her case however if she was presumed dead her assets would have been taken by the crown, who would then seek an heir. If none could be found then the estates would be sold and the balance transferred to HM treasury.
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After 7 years they're declared dead. The estate will be given to family members or the government will retake possession of it.
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Why do we think of nature as pretty?
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Well, i like Plato lately, so here goes. The world is chaotic and in constant flux. The forms exist "out there" and are static and unchanging. The static and unchanging forms are what is really real, and the physical world as such is less real, it is only real to which degree it participates in the forms. Beauty as a form exists and things, to various degrees, participate in that form. Think of the Form beauty as the measuring stick of beauty. Nature participates in beauty (in varying degrees), so the reason why we think that nature is beautiful is because it participates in Beauty itself.
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Nature is quite big, but I think I've understood what you're asking. If I may rephrase: Why do we find the beautiful things in nature so beautiful? Beautiful things in nature, such as a clear sky or large body of water, is so beautiful to is because of evolutionary factors (in essence). In the early days when humans were still evolving, things like clear skies and large bodies of water helped promote survival. Water to quench thirst and clear skies to allow free movement and visibility (amongst many other factors). Because of this, humans have generally favored clear skies and beautiful scenery because it generally means it's easier to do all the other things we need to do in order to survive. In the olden days it was to be able to hunt and find water/shelter) and in the modern era we can do anything we want (go fishing, shopping, work, etc..). Hope this shed some light on the topic!
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How do cats know when it is going to rain or storm?
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They don't. I have 2 cats that have free access to the outdoors. And when a sudden rain storm arises, they come back in soaking wet. They have no clue it's about to rain.
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Other animals can more accurately detect changes in pressure and temperature. This allows them to know a storm is coming, and maybe the severity of the pressure and temperature drop, but not much more than that.
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Liquid fluoride thorium reactor. How do they work as opposed to conventional nuclear reactors?
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There are a few main differences. First is the fuel and coolant is a molten heterogeneous mass. That means its already melted and can't "meltdown". Second is the core doesn't directly burn thorium. Instead thorium absorbs neutrons from the core and undergo beta decay to change into U233 which is the actual fissile fuel. That means the core can breed its own fuel, and with proper processing you can separate waste products and have much smaller volumes of waste as well as process out fuel and make concentrated fuel for other reactor types. Third is it passively shuts down. There is a freeze plug which melts if the reactor starts to overheat. The core material then relocates to another storage tank which has a geometry and neutron absorbers which stop the nuclear reaction. There are a lot of other good details, look for the 5 minute Kirk sorensen video.
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The are hydraulics actuator that move them. You can for example see them [_URL_1_](_URL_1_) at the top of the reactor and moving [controllrods in reactors](_URL_0_). The one in the video is research reactor and not power plans.
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The Difference Between Radians and Degrees
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Radians are the more natural measure. To understand why, look at [this picture](_URL_0_). The angle between the two red lines is, in radians, *precisely* the length of the red arc. And this relationship holds for any angle you choose: 1) Draw the angle inside the circle with the vertex centered at the origin. 2) The radian measure of the angle is *precisely* the length of the arc you end up with between the two lines. If you change the circle to have some bigger radius, then the radian measure becomes the ratio between the length of the arc and the radius. Since the full distance around a circle is 2π times the radius, the radian measure of a full circle is always 2π.
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A degree is a given fraction of a given scale. When talking about angles, a degree is a given fraction of a full cirle (360°), when talking about temperature, a degree is a given ammount of a scale. ( This however makes more sense looking at the Celsius scale, because as 100° means water boiling, 21° could also mean "21% of the water's boiling temperature, so 21° means here the 21st fracture of a scale 0-100° ). EDIT: Another user mentioned the latin origin. "De Gradus" literally means "In steps of...." so you get the idea. A 45 degree angle is "45 steps on a ( 360 step ) circle. If you call someone "stupid to a certain degree" you are expressing something similar. The person is not fully retardet, you know there is headroom left, but hell, he is dumb.
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Why is argon so abundant in the atmosphere?
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Argon is a byproduct of a lot of radioactive processes (e.g. radioactive decay of Potassium-40) that naturally occur in rocks. As it is a gas, it will eventually end up in the atmosphere, where it will build up as it won't react with anything else (being a noble gas) To quote [wikipedia](_URL_0_): "The argon found in Earth's atmosphere is 99.6% 40Ar; whereas the argon in the Sun – and presumably in the primordial material that condensed into the planets – is mostly 36Ar, with less than 15% of 40Ar. It follows that most of the terrestrial argon derives from potassium-40 that decayed into argon-40, which eventually escaped to the atmosphere."
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The most likely source for the 0.93% Argon on the atmosphere is likely due to a radioactive decay process from K^40 to Ar^40. In geology, we have a radiometric dating technique that can use the K^40 /Ar^40 ratio to determine the age of some rocks otherwise deficient in other elements used for radiometric dating (or conveniently enriched in K). The problem is, when K^40 decays, it can decay into Ar^40, which is a gas. Sometimes, gas bubbles can get trapped in a rock, but over time, many of these bubbles could have escaped into the atmosphere. And bingo! We see that in the atmosphere, the most common isotope present is Ar^40 , which must have been by the decay of K^40 over time. **TL;DR:** All of that 0.93% of Argon in the atmosphere is 99.6% Ar^40 , which comes from the radioactive decay of K^40 into Ar^40 within the Earth's crust. [Source](_URL_0_)
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Why does Oklahoma have so many earthquakes when it's not on a fault line?
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There is a fault southwest of Oklahoma City called the Meers Fault. You can use [this map](_URL_0_) to view where it is and you can [read more about it here](_URL_1_).
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[Earthquakes are happening all the time](_URL_0_), what usually changes in the degree that they are being reporting in the media. And, whenever you have a series of almost-independent largely-random events, you will end up with clusters for no other reason than chance. Single earthquakes can, sometimes, represent foreshocks, but there isn't really any good/reliable way to distinguish those from earthquakes that don't. There is some research looking at whether earthquakes can have "far-field" impacts in triggering other earthquakes, but even if that is the case the signal isn't very strong so it's not a major factor. I'm not really familiar with whether anyone expects that to have significance across a large distance of continental plate either. Basically, unless something else unexpected comes to light, there is no reason to think the Oklahoma earthquake is any more significant than the other one to two thousand earthquakes every year that are magnitude 5+ (except for people living in Oklahoma of course).
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Year-old container of cream - what happened?
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Your whipping cream separated into curds (the gloopy layer) and whey (watery layer). Most likely this happened because a bacteria got into the cream and converted the lactose (milk sugar) into lactic acid. The increased acidity caused the cream proteins (casein) to clump together and form the gloopy mass. The smell and taste of the curds is determined by the type of bacteria introduced into the cream so it can range from odorless to extremely pungent.
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It is unlikely that anything happened to it. At refrigerator temp (37 F) I would guess that yeast would not grow very rapidly. I'm presuming your container was sealed. If the top was exposed to air, then read on and you'll see why that is important. If yeasts did grow, they would produce first alcohol and CO2. So the bottle would develop some internal pressure if sealed. Depending on how much oxygen was also in the bottle (ie, how much air was above the liquid), the yeast would also digest the alcohol and convert it to acetic acid (vinegar). So it all depends on the temperature, the time, and how much oxygen was available to the little yeasts. One approach would be to open the bottle carefully, and take a sniff. It may smell like plain old cider, vinegar or booze.
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Is it true that some US Marines mailed the skulls of dead Japanese soldiers that they had killed home to wives/fiancées/sweethearts?
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Yes. The desecration of Japanese war dead is something I touch on in [this post](_URL_0_) although the overall focus of the piece is much larger.
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The wiki actually does a great job describing it _URL_0_ In short, they were selected from a group unknown remains from each WW I, WW II, Korea, and Vietnam. The soldier from Vietnam was identified later and now that section remains empty, and with modern DNA analysis and records, its unlikely that there will be any more remains added.
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Why are my muscles sore after jumping in cold water?
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From what I understand, our bodies defenses against hypothermia is to shiver. This involves involuntary muscle contractions to generate heat. These muscles contractions still can cause muscle soreness just like working out.
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It reduces inflammation in muscles, which is why someone would do it after a race. Like putting ice on a sprained muscle, except you put it everywhere to treat minor soreness. Some of these athletes probably believe that activating the body's adaptations to cold has wider ranging benefits; they probably take ice baths all the time. Some probably use saunas and ice baths. This is an emerging area of research, there are some plausible biochemical mechanisms, but it isn't proven. [This talk by Dr. Rhonda Patrick at the Biohacker conference is a good intro to the concept](_URL_0_). Perhaps Dr. Patrick is wrong, maybe she takes credible science and makes untenable connections between one fact and another. But you can't deny that she has done her homework, this is a higher standard of reliability than some Dr. Oz bullshit.
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Difference between solids and gases during expansion?
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You're putting the cart before the horse and forgetting the yoke: * A gas will expand when heated. * A gas will contract when cooled. * A gas will heat when compressed. And: * A solid will expand when heated. * A solid will contract when cooled. * A solid will heat when compressed. Notice how both have the exact same behaviors? Some specific materials will do some funny stuff (involving phase changes, even within a state), but this is a good rule of thumb for most things.
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The gases are lighter, so they move first when pressure is applied. So the order of operations is gas, diarrhea, then solids. You shart yourself when you underestimate the gas to diarrhea ratio.
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Prior to the the 1900s, air conditioning didn't exist, people wore wool and cotton, and baths were infrequent. Was everyone just horribly uncomfortable all the time?
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If they didn't know the joys of controlled climate and good hygiene, how would they define "standards?" Comfort is relative. It's only bothersome if you're not used to it.
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You can't be phobic of something you're not even aware of... in the same way that no one at that time had anxiety around flying in an airplane. There were "neat freaks," but they wouldn't have thought in terms of germs or disease, just dirt and cleanliness.
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how do people dive into those tiny swimming pools unharmed?
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You're talking about as part of a stage show? Where someone does a high dive into a shallow pool? They just do a belly-flop. Hitting the water like that makes you stop much faster and not hit the bottom of the pool.
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They wear a device called a BC (for buoyancy control). Usually it is a sort of vest with an inflatable bladder inside. Air from the tanks is redirected to the bladder to make the diver more buoyant, and released to make them less. Divers also typically wear weights to ensure they can sink if necessary, and that be released in an emergency.
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What is the difference single-cycle, multi-cycle, and pipelined processors?
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A single-cycle CPU executes one instruction at a time, and each instruction takes one clock cycle to execute. One disadvantage here is that your clock speed can only be as fast as your slowest operation. A multi-cycle CPU executes one instruction at a time, and each instruction may take multiple clock cycles to complete. This may sound slower, but it can allow for a much higher clock speed. A pipelined CPU executes several instructions simultaneously, and each instruction takes multiple clock cycles to complete. Most high-performance CPUs are pipelined, as their throughput can be much higher.
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Multi-processor: Two or more separate processor core chips each in their own IC package. Multi-core: Two or more processor cores in printed next to each other on the same silicon wafer packaged in the same IC package. Multicore is faster (aside from clock speed there fewer hops for data to travel) and uses less power than the older multiprocessors (voltage requirements have been decreased and components got smaller). Multicore isn't a new idea but now with smaller silicon printing and lower power requirements it's possible to cram millions of gates and transistors in a very small area and not melt the wafer. Modern operating systems are also making better use of multiple CPUs then previous generations.
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Is visible light, or any other form of light for that matter, affected by wind?
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Wind is accompanied by variations in air pressure and that variability induces variations in the refractive index of the air. Those variations will result in slight wobbles in the direction of light. It is for this reason that stars twinkle.
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Plenty of gases have color in their pure form. We can see shadows on hot days because air expands and then moves. And light changes a few properties when switching between mediums, so that movement of air and change in density is what makes the light wavy (gives interference patterns). But the gases in air do not reflect in the visible range. Which to be honest is kinda the point of us evolving this specific visible range to see in (so air wouldn’t get in out way).
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How exactly does windchill work?
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Moving air cools things faster, and thus "feels" colder to living things. The windchill temperature you hear from weather reports is an approximation of how cold it "feels" to a person. If you left a hot knife outside when it's -20C with no wind, it will cool to -20C slower than if there was more wind. EDIT: Just wanted to add, this is also why blowing on a hot liquid cools it down faster.
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Via Google Wind is air in motion. Wind forms when the sun heats one part of the atmosphere differently than another part. This causes expansion of warmer air, making less pressure where it is warm than where it is cooler. Air always moves from high pressure to lower pressure, and this movement of air iswind. It's a pretty simple concept. This is why climate change is so terrible and why we get once-a-century Frankenstorms in consecutive years. Abnormally warmer air equals stronger winds.
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Why is hemoglobin trapped in red blood cells?
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Well free haemoglobin in the blood plasma is toxic, with free haemoglobin resulting in hypertension (as it removes NO, a regulator of vessel diameter and thus blood pressure) and is also toxic to the kidneys. This has sadly stopped it being used as an oxygen carrying blood substitute. _URL_1_ Further red blood cells do not only exist to carry haemoglobin, they also contain other enzymes which act to regulate the blood, such as the role its enzyme carbonic anhydride plays in pH regulation. _URL_0_
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You could have found the answer on Google much faster. Anyway, I'm fairly sure /u/rsdancey is wrong. It binds with the haemoglobin (which is supposed to bind to oxygen to carry it from your lungs to other parts of your body) on your red blood cells and forms a much more stable compound than if oxygen were to bind with it instead. Since there's no haemoglobin left to bind with the required oxygen, you essentially suffocate from the inside.
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Are different atoms of the same element identical?
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Two real atoms, i.e. that are not infinitely far from all other atoms etc., are certainly not identical. The electron density and nuclear spin densities will be affected by their environment and can even be distinguished. This is what the entire fields of MRI and NMR are based upon.
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You cannot tell the difference between two protons. They are what physicists call identical particles. It may be tempting to think "I can call this proton proton one, and this proton proton two." But there's an old saying that goes "you can't paint an electron"; there's literally no way of telling one proton from the next. It's tempting to say something along the lines of "Well, if all the protons in my penny are changed with protons from different pennies, what are the effects?" The answer, though, is almost that the question doesn't make proper sense. All protons are exactly the same. The english language is almost not designed with the proper structure to refer to identical particles. This goes for the protons, neutrons, electrons, and quarks inside anything. If it's an identical particle, you can't tell one from the other because there isn't a one and the other- there are just two. [Wikipedia on identical particles](_URL_0_)
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What stopped Spain and Portugal from claiming the Magreb region of Africa and attracted France to it instead?
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If I am correct, Spain launched numerous crusades into north Africa capturing cities like Oran (1509), Melilla (1497), and Tripoli (1511), however they were not able to hold them for long. Portugal also launched crusades into Morocco, capturing Ceuta (1415), Tangiers (1471), and Mazagan (1485). Although Portugal was able to retain their possessions in Morocco longer than Spain was in North Africa (lets just ignore Ceuta, and Melilla here). The Barbary region itself was not very important to commerce (trans-saharan trade declined greatly following the establishment of Spanish and Portuguese colonies in West Africa), and were very resistant to occupation by, at that time, an enemy without a massive technological advantage. Hope this helps!
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Because it would have violated treaties with Portugal. The Treaty of Tordesillas (1494) established a line of demarcation in the Atlantic. Spain was granted rights to lands westward, Portugal to the east (it travelled through Brazil this allowing colonization there). The line confirmed Portuguese feitorias in Africa and their desire to get to the Indian Ocean and beyond. It also confirmed papal bulls to both nations that supported their expansion as long as they spread the Gospel in lands the reached. In 1529 the Treaty of Zaragoza extended that line around the poles but not perfectly (Portugal received 191 deg. and Spain 169 deg.). Spain's eventual conquest of the Philippines violated the boundary, but did not target an area of Portuguese trade.
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Why do some courts insist that people swear on the bible, if the bible itself says swearing by or on anything is basically a sin?
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The text in question is from Matthew 5 (NKJV): 33 “Again you have heard that it was said to those of old, ‘You shall not swear falsely, but shall perform your oaths to the Lord.’ 34 But I say to you, do not swear at all: neither by heaven, for it is God’s throne; 35 nor by the earth, for it is His footstool; nor by Jerusalem, for it is the city of the great King. 36 Nor shall you swear by your head, because you cannot make one hair white or black. 37 But let your ‘Yes’ be ‘Yes,’ and your ‘No,’ ‘No.’ For whatever is more than these is from the evil one.
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If we divide curses into three main categories (blasphemous, sexual, scatological) then in the early modern period (1500-1800) blasphemous oaths are more common relatively than they are today. So 'By God,' 'God's blood,' 'God's wounds,' 'God blind me,' and a wide, wide variety of religious profanities are much more taboo or offensive than they are today. Cunt, fuck, and swive (basically a synonym of fuck) are the primary sexual profanities. One of the interesting things about profanity is that the taboos shift: in 1960 'By God' was innocuous but 'Fuck' was unacceptable, today fuck is increasingly acceptable but racial or homophobic slurs are much less so. Indeed, you could say that those slurs are becoming or have already become the new profanities-- you more often hear the euphemism 'n word' than 'f word.'
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How does a commercial “slushie machine” create such a perfect slurry of chewable ice?
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There is a metal cylinder that the flavored liquid is dumped into, and on the outside of the cylinder is a bath of freon or other supercold liquid. Inside the cylinder is a set of paddles that constantly rotate and scrape any ice crystals that form off the cylinder walls. So the instant a tiny ice crystal gets formed in the slush liquid, it gets scraped loose. That's how they do it. You can make the same stuff if you have an ice cream machine. Same process but just a different starting liquid.
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They remain at a constant cold temperature and continuously spin. That agitation of the machine is partially to keep the water from freezing solid. Some of the slushy machines have additives to make the freezing temperature of the mix lower, so that the drink can be much colder.
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Why does installing files take longer than uninstalling files on computers?
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Uninstalling, or just generally deleting files, is a very quick operation. Instead of actually removing the data from the disk, it just removes the file from the filesystem and marks the space where it used to live as available for reuse. This is why you can "undelete" files. You just have to figure out which blocks on the disk used to hold the file and recreate the directory entry. You have to be quick though because some other file might get written over those blocks.
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1. Badly designed software un-installation mechanisms on windows 2. Increasing complexity of newer versions of the same software 2. Perception of slowness from looking at newer faster computers.
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What is preventing nanotechnological inventions (from graphene, for example) from hitting the market?
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It takes time to move a new substance like graphene from the experimental/theoretical realm to mass production. They have barely figured out how to make it let alone how to make lots of it cheaply and reliably. I'd imagine well start seeing all sorts of products in the next 3 to 10 years.
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Diamondage's comment illustrates the point pretty well. A lot of nanotech allows for improvements based on a better understanding of how nanostructures are formed. Its kind of like how you can ask what quantum physics has really done, until you examine how p/n doped semi-conductors work, and realize how crucial that advance was. Specifically, advances in themo-electrics, electrode materials, etc. Nanomachines are just much sexier, so thats what youre sold, despite other applications being incredibly lucrative. The whole "nano" label suffers from being to broad.
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What kills houseflies?
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So I couldn't find pertinent data directly on the subject, but according to [this paper](_URL_0_) on the leading causes of death in *immature* houseflies. Immature flies die mostly from: > desiccation, pathogens, adverse environmental conditions and damage by insect parasites It's reasonable to assume these factors are big killers of adult flies as well. It's really hard to find anything on mortality of adult flies without turning up 1000 papers that are studying how they respond to various insecticides.
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I'm assuming you mean Drosophila melanogaster (_URL_0_) or one of its relatives as opposed to other fruit fries (if you are referring to the agricultural pest, they may come from eggs laid in fruit). These flies likely get into your house via small holes in the exterior, cracked or opened doors (even just while someone is entering/leaving), or other small openings. Houses, especially older ones, aren't known for being airtight enough to keep out small insects.
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Why do North and South Korea have totally different names in Chinese? NK is 朝鲜 and SK is 韩国.
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The Chinese use the same Chinese characters for North and South Korea as those countries use to refer to themselves. 朝鮮 (Chosun) was originally the name of the royal dynasty that ruled the Korea peninsula from the 14th century until it ended with Japanese occupation. Around the end of the 19th centruy they came up with a new name to refer to the country, 大韓, (Daehan) for political reasons. When the peninsula was divided following WW2, two different governments were set up, the one in the North decided to use the old name, the South stuck with 大韓民國, commonly abbreviated to 韓國 (Hanguk). They refer to each other by using the name for their own nation plus the prefix of North or South. So the South refers to the North as 北韓 (Buk-Han) and the North refers to the South as 南朝鮮 (Nam-Chosun), both governments predending that they have authority over the entire peninsula. In China and Japan they use the names that each country uses for itself.
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All the Kim's in Korea are self selected last names. Until the 1890's no Koreans had last names unless they were royalty. So then their Japanese overlords forced everyone to pick a last name. Kim's, Park's (Paks) and Lee's were some of the richest and most powerful royalty, so everyone picked one of those names, as they were the most badass names available. That's why most people in Korea have one of those last names.
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Why do airplanes need to fly so high?
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There are generally a few reasons. One of the biggest being that higher altitude means thinner atmosphere and less resistance on the plane. There's also the fact that terrain is marked by sea level and some terrains may be much higher above sea level than the takeoff strip and they need to be able to clear those with a lot of room left over. Lastly, another good reason is simply because they need to be above things like insects and most types of birds. Because of the lower resistance, at higher altitudes, the plane can almost come down to an idle and stay elevated and moving so it also helps a lot with efficiency. Edit: Forgot to mention that weather plays its part as well since planes don't have to worry about getting caught up in the lower atmosphere where things like rain clouds and such form.
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First, the word is aerodynamic. Second, air resistance is *higher* at lower altitudes because air is denser there. There is less drag higher up. Flying lower is not safer. At a high altitude, a plane that develops a problem has time to fix the problem or go to a different airport. A plane at a low altitude has to land where it is, which may be very bad.
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What makes some words start with a 'ph' but other words start with 'f'
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Because the Greek people had a phi and when the Greek was transcribed into Latin, they used a ph instead of an f for the letter "phi".
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Each character in Chinese has its own meaning with "words" often represented by multiple characters. Ex) Airplane - 飛機 - Fei Ji - Flying Machine. Other words, usually borrowed from other languages, are spelled out phonically as best as possible. Ex) Coffee - 咖啡 - Ka Fei To abbreviate, one can - Keep only characters that give the most information - Keep characters that distinguish the abbreviation the most - Catchy combination of both - Catchy description of original word Few examples: 台**北車**站 Taipei Train Station (Tai Bei Che Zhan) = > 北車 (Bei Che) **珍**珠**奶**茶 Boba/Pearl Milk Tea (Zhen Zhu Nai Cha) precious-pearl-milk tea = > 珍奶 (Zhen Nai) precious milk 臺**北**市立第**一女**子高級中學 Taipei First Girls' High School = > 北一女(中)
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Why do some foods spoil quicker than others?
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Foods that spoil quickly are full of nutrients like simple carbohydrates and proteins for molds and bacteria. They're also hospitable to microorganisms i.e. damp, not too acidic or salty, and relatively porous or not too dense so a colony can grow into the food. E.g soft cheeses spoil easier than hard cheeses because molds can send their tendrils of mycelium into the cheese. Drying foods preserves them since microorganisms need water. Salting food also has the effect of making it relatively inhospitable.
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Bacteria & exposure to air are the source of most food spoilage. Sealed products in cans, jars, bags, tetrapacks, etc have been heated enough to kill the bacteria & had the air sucked out, giving them a long shelf life. Once you open them, air & bacteria start getting back in & the food can start to spoil again.
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Why does time seemingly pass so fast when I'm lying in bed and can't sleep?
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There's a good chance you are sleeping some of the time, but don't realize it. Probably not a deep, restful sleep if you are repeatedly flitting in and out of consciousness. But it will make time seem to go by quickly.
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Because logarithmically a day becomes faster. When you are 1 year old waiting a year is waiting an aditional 100% of your life. But when you're 50 years old, 1 year is only 2% of your time. The way we experience time is logarithmically not arithmetically. A bit of a over simplifyed answer, but hell this is ELI5.
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How does Edward Snowden know so much information, and why is his word still relevant after so long being away from the country?
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This is from memory so my facts may be a little off. He was a systems administrator contractor at the NSA. Essentially, his job was to provide access to information to relevant people to ensure that no one had more information than was necessary for them to see. However, that meant Snowden had copious amounts of data at his fingertips. How Snowden obtained the data was by downloading it to flash drives and taking it out of the facility. Although his data access was tracked, there was no suspicion due to the fact that he would be expected to access lots of data. The amount of data he took is enough to disclose information in bits over a long period of time. And, this is my guess, it seems that Snowden is continuing to use the data as leverage, and punishment, until the US government changes policy on spying.
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Obama campaigned on reducing the power of government to gather info on what US citizens do with their phones and Internet. Snowden (the guy who left the country) released a bunch of documents that show that the US government has been collecting huge amounts of info about who people call and what they do online.
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Why is Margaret Thatcher a controversial figure?
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Margaret Thatcher last held political office in 1992. So it's safe to discuss events regarding the events that polarized popular opinion regarding her. This question has been asked a few times in a similar though not exact vein with this one _URL_0_ being closest to what I think you are after.
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hi! FYI, a similar question came in a couple of days ago which generated some discussion. The post also includes links to several more [How was Margaret Thatchers tenure as Prime Minister? Why is she so hated](_URL_0_)
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Can someone ELI5 why this water simulation works very well in a web browser, but is hardly used in video games?
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(I think this is the problem) Although this water simulation works awesome you have to be careful when using it on a larger project. The first thing to notice is the number of polygons or shapes used in this project. This whole project is simply a cube and ball. This makes the program use so little cpu because there are less polygon to render (In this project there are probably less then 500 polygons) Marcus from Gears of War was around 15,000 Polygons and with enemies there could be lot more. This would increase the processing power needed and make the game run slow.
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Water is made of lots of tiny particles, and these particles are constantly moving, colliding, and changing velocity. Solids have lots of particles, but they don't move, and you don't have to calculate their speed, or how they change position. It's harder for a CPU to calculate how to display water since there's so many calculations. Each time one water particle changes position, it will affect the ones next to it, which end up affecting all of the water particles. Forget making it look pretty, even trying to simulate water flow is hard, and there aren't precise equations to deal with laminar (smooth) and turbulent (rough) water flow. We can't simulate the path of each individual molecule accurately, so instead we guess and fudge it a bit. It's much easier to make realistic solids, since you don't have to worry about what's happening inside the solid, and the surface isn't changing much, if at all. --- TL;DR too many calculations
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When technical support tells you to unplug your router/modem for 15 seconds, does the number of seconds actually matter?
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Yes-ish. The power supply in your electronic device has capacitors that allow it to keep working during small power dips. Having 5 secs of power carry cuts down on reboots. 15 secs is probably chosen to make sure you unplug it for 10. Some environments, where you have power over Ethernet devices, you also need to unplug the network wires to completely drain all the logic power.
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The computer code that electronic devices use is written imperfectly. Due to the way code works, it's easy to have problems that only show up after the device has been powered on for a long time, and difficult to catch these problems when you test the device. So when you unplug and plug back in your router, you're just making it so the device hasn't been powered on for a long time, and this ends up solving all sorts of subtle problems that nobody really knows about.
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Biologists of r/AskScience: In regards to evolution, could there have been more than one, independent, cells that gave birth to their respective trees of life? if not, why?
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One strong piece of evidence is the conservation of the genetic code's 3-nucleotide codon - the 'code' by which DNA is translated into proteins. Three bases specify an amino acid. C, then A, then G, for example, is code for the amino acid Glutamine. There are 64 possible base combinations to code for the 20 amino acids used in protein synthesis. With few exceptions, *every single living thing* uses the exact same code to produce the exact same amino acids. You use the same code as an e. coli bacterium. The odds of two separate trees of life independently developing this precise mechanism are pretty thin.
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Life could have started a billion times with a billion different outcomes. However, the common traits of DNA in all living things on earth, show that there was one really successful line. Only one survived to take over the planet.
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Looking for sources/input on daily use of paper in imperial China (preferably Qing)--English or Chinese
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You might be interested in some more information on the "Paper Collection Bureau" you already cited. Here is a link to the entire passage in William Rowe's book: _URL_1_ Source for the passage is: William T. Rowe, Hankow: Conflict and Community in a Chinese City, 1796-1895 (Stanford University Press, 1992), 103-104. Rowe also talks about a literati-funded program to provide stationary and paper to impoverished academy students: _URL_0_ Same source as above, page 182. Hope that helps!
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Hello there! The best thing you could do is check out our [book list's section on Chinese history](_URL_0_) as it contains both general works and more period/subject specific books. Hopefully that gives you a good starting point.
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Does saving a digital file (like a PDF) to an object (like a hard drive) change the mass of the object it’s saved to?
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No. It is simply the moving of magnetic switches from the "Off" position to the "on" position, and vice versa. There is no mass change.
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Permanent storage in computers generally is done by one of two technologies. For magnetic hard drives, there's a spinning plate covered with magnetic material and a mechanism that allows to detect and change the "direction" of the magnetism in very very small segments of that platter. So writing a file would involve that mechanism changing the magnetic pattern on the disk. For solid state drives (SSD) in computers, as well as the common USB flash memory sticks, the memory consists of a silicon chip with lots and lots of very small isolated conducting spaces which can store electric charge (extra electrons), and transistors to control that. Writing to that memory involves storing electric charge in some (and removing from others) of these "pockets" called NAND cells. Both of these things are somewhat permanent and continue to persist after power is turned off.
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Why is calling someone a Dutch Wife considered an insult? NSFW?
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A Dutch wife is a body pillow - - but also slang for a blow up doll.
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Hi, not discouraging other contributions here, but you may be interested in this earlier thread * [Why do we call people from The Netherlands "Dutch"?](_URL_0_)
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How do they form the giant snow ramps at the Winter Olympics? And how do they prevent it from wearing down from use while still allowing it to be soft enough to land/crash on without breaking every bone in your body?
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For starters, they typically have solid molds that are covered in a lot of snow in order to keep the jumps from changing. The angles of the jumps and landing ramps are calculated, but the landing part is still the responsibility of the rider.
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Its a form of on demand traction for snow and ice. Essentially its the same as having chains wrapped on the tire when needed. _URL_0_
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Why were Europeans and Asians able to advance technologically while natives of North America, South America, and Africa were not?
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Try reading *Guns, Germs, and Steel* by Jared Diamond. He attributes the discrepancy to the way Eurasia is a large landmass in a relatively small latitude range, allowing people (merchants, warriors, etc), crops, germs (Europeans much more resistant to germs compared to Native Americans because they're exposed to more years of germs from across the continent), livestock, you name it, to propagate through the whole continent. The rise of large polities is possible because of this, and large societies are, arguably, the root of advanced technology and everything that comes with it.
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By Native Americans, do you strictly mean North American natives or would you also include Mesoamericans or South Americans? Mesoamericans invented maize and Andeans invented the potato. Those are fundamentals of modern agriculture.
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Why are Guantánamo inmates who are cleared of all charges still not being released?
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Nobody will take them, not even the US. When Obama was trying to shut down the facility in his first year Congress and States put in barriers to prevent him from transferring them to the mainland. Other countries that the inmates came from don't want to accept the inmates either. Hence why the facility is still open.
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The president decided that a terrorist could not be tried in either the military court or the United States court system. For several reasons, including the the part where we can't torture enemies in the United States. He came up with this brilliant idea that if we created a whole separate prison for those that are deemed terrorists and they are not in the United States criminal system nor are they in the military system certain rules can be broken and other laws and penalties can be made for them. The problem with this is that a lot of people dont agree with what happening, obviously. Although President Bush has said that the certain techniques used in Guantanamo bay have proven very helpful, it is ultimately unconstitutional. To add onto this if president feels that anyone is a threat to the united states he can make the decision to send them to Guantanamo Bay under ANY circumstance.
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Why do they make different insect killer sprays for different types of insects (wasp killer, flying insect killer, ant killer, etc.)? Wouldn't they all do the job since they're all poison?
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A lot of has to do with strength, and spray pattern. Wasp spray needs to be extra strong and spray on a stream to get inside the nest. Flying insect killer needs to spray a mist to stay in the air and continue killing. In addition some bugs, like spiders, breathe through their skin and some poisons don't work on them for to this. I have sprayed was with spider spray and it works. I have killed ants with wasp spray.
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> How do insect and bug sprays kill insects but don't harm us Most insecticides target specific aspects of the insect nervous system which are different from those of humans and mammals in general. These neurotoxins have various different types so getting into the details can be quite complex, but the general idea is that insects are sufficiently different for specialized substances to be toxic to them and not really for humans.
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how the first programers of videogames make their game wthout any program? (really eli5 pls)
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The first video games were usually made by physically designing the hardware to do what you wanted. There's a course out there called NAND to tetris that actually takes you from physical NAND logic gates all the way up to making a functional game of tetris if you really want to learn in-depth about it.
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Big programs are build incrementally, in small steps, one small feature at a time. A game isn't made as a whole in one big step, but as a collection of many individual systems that get iterated on a lot. Game (and game engines) are usually made this way: * create a program that opens an empty window * make the program initialize a 3d context in the window * make the program display a colored triangle on a solid background * make the program display a single 3d cube * make the program display a model loaded from disk * make the program display several objects loaded from disk * add lighting and other eye candy * add gameplay.
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If medical advances are at the point where organ donations and skin grafts are available, why can't women undergoing breast reduction donate breast tissue to, for example, mastectomy patients who need reconstruction?
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The reason a lot of women opt out of reconstruction isn't because of a lack of tissue/implant to fill the area, but because of risk associated with the reconstruction. Many women who have had a mastectomy are unwilling to undergo additional surgery and fear that tumors could grow in the reconstructed breasts. These women choose to go flat and/or to wear a specially padded bra. Most don't consider their mastectomy a hindrance and would prefer to just be done with everything once the cancer is removed.
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Not sure if you're in the states or not. There is a whole bunch of red tape regarding US living organ/tissue donation when compared to organs/tissue procured post mortem. Short answer is that everything needs to be in place with compatible recipients lined up to receive the organs (because skin is technically an organ). I suppose it could be done, but I'm not sure that there is a shortage of skin like there is for more perishable organs. for a PDF with more info from the USgov site go [here](_URL_0_)
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When you take a particularly harsh bowel movement, why do you get that brief rush of pressure to your head?
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You've got a very long nerve in your body that runs all the way from your brain down to where you poop. When you bear down (push really hard to get the poop out) you can stimulate that nerve. That nerve happens to be in charge of some very important stuff in your body, like telling your heart to slow down, telling your blood vessels to dilate (reduce your blood pressure) ect. So when you stimulate that nerve by pushing really hard on a big poop you sometimes make it cause those things when you don't need them to happen. So suddenly your blood pressure goes down and you feel it first in your head (cause gravity, and your brain is important). This sometimes causes people to pass out. This is the Vagus nerve and the term often used is a "vasovagal response" meaning your vessels responding to your vagus nerve. Or even "vasovagal syncope" which means temporary loss of consciousness that resolves quickly due to vagus nerve stimulation.
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Because the signal for pain travels through your nerves, to your brain, in big slow waves. Lot's of the very basic and 'primal' feelings like pain and hunger travel on very slow and 'primitive' nerve networks. That's why there is a delay between eating and feeling full. And why more complex feelings can override pain, like pressure or itching. Your bowel moves in long, 20 minute waves. When you have to poop really bad and it feels like it's going to force itself out... then goes away. Well the next wave has already started at the top of your gut, and the movement slowly works its way down your digestive tract... moving everything a bit. Then when it gets to the end you get that overwhelming urge to poop again. I hope this was helpful, there was a great national geographic documentary I watched where I learned this stuff from. Maybe it's on netflix or something now.
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If proper DNA replication is so crucial, why does nature "allow" de novo mutations? Why are DNA repair mechanisms not 100% failproof?
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The sort of question this is makes it difficult to form testable hypotheses, and so if anyone manages to find citeable literature on this, I'm going to be super impressed. From a systems perspective, I can think of one reason, and from an evolutionary perspective I can think of another. Systems perspective: Cellular processes are often robust to perturbation, but the generation of robustness comes at energetic and time costs. Creating an even more error-resistant DNA repair mechanism might be possible (though difficult), but at what energetic cost to the cell? What about efficiency costs? Would this make DNA replication or transcription take longer? There is a tradeoff here, it is not a simple "DNA fidelity > > everything else". From an evolutionary perspective, it is possible that, in the long run, organisms with super-exacting repair mechanisms might be less adaptable to changes in environmental conditions, making them LESS robust than more error-prone neighbors.
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Because of the complexity of the protein engines at work. All told, there are a considerable number of steps necessary to correctly replicate DNA, and the process is different for the leading and lagging strands. However, I think on average there's only one error for every 10,000 replications. Most of these "mutations" are harmless. Some are bad and apoptosis signals cell death by suicide. Some are bad and don't initiate apoptosis and could possible lead to cancer. However, some are beneficial. And therein lies the rub. But be glad, because without that error, evolution wouldn't occur. This video gives you a sense of how complicated it all is. _URL_0_ /biochemist
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Without mass production, how did Rome supply it's vast armies with weapons and armor?
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I'll just leave this here. [Industry of the Roman Empire](_URL_1_) TL;DR Roman industrial production (especially metal production) at the height of the Empire was not to be exceeded until around 1750 - the beginning of the Industrial Revolution. Edit: Also, Romans certainly had mass production, so the question should be tailored more towards modern industrial practices, or something like that.
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You may be interested in [this recent thread](_URL_0_) in which I shared a reconstruction of Roman military rations. That is not to end the discussion so much as to keep you busy until a new answer comes along.
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Is there a defined time in recorded history when people starting making music together aka a band/orchestra prior to the Middle Ages?
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Hi there - at one level, there *isn't* a defined time when people started making music together - hunter-gatherer peoples the world around appear to make music together, though clearly their music works in different ways to that of a symphony orchestra or a rock band. So the point when a group of people with instruments got together to make music is almost certainly prehistoric. At another level, people before the Middle Ages did talk about music, and [the part of the FAQ that deals with music in antiquity](_URL_0_) has some great responses from /u/erus, /u/racecar_ray, and /u/verbee about music in ancient times.
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In the western world, it arguably would have been around the time of the formation of a guild for musicians (minstrels) in Vienna in 1288 - Nikolai Bruderschaft (St. Nicholas Brotherhood). This was the first recorded guild for musicians. Some info and a few references here. _URL_0_
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What is the difference between ADD and ADHD?
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> ADD is an older, and not medically used term. (Although it still lingers, sometimes.) > ADHD is now diagnosed on a 3 factors -- one for inattention, one for hyperactivity, and one for impulsivity from one-ten on each. Most children have a mixed score, and treatment proceeds from there. ADD under the current scoring would have higher scores on inattention and lower scores on the other two. Theoretically, there can be a child who would be 10-0-0, but typically its 7-4-8 (like my child). _URL_0_
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Some things cause people without ADD/ADHD to have trouble focusing: A noisy environment, stress, distractions, and tons of other things. The difference is that with ADD/ADHD people, the inability to focus remains even after you correct for all of that. There are also some other symptoms that come with ADHD. For adults, they are listed as follows from the mayo clinic: Adult ADHD symptoms may include: * Impulsiveness * Disorganization and problems prioritizing * Poor time management skills * Problems focusing on a task * Trouble multitasking * Excessive activity or restlessness * Poor planning * Low frustration tolerance * Frequent mood swings * Problems following through and completing tasks * Hot temper * Trouble coping with stress You need 6 to qualify, and they have to be pretty constant.
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Was Galen (Aelius Galenus) a member of the gens Aelia or not?
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Freedmen would often take the name of the family who freed them (and who they were often adopted into), so it's possible that he was descended from a freedman. He and his father were both from Pergamon, which was very definitely Greek. In addition his father's name was Nicon/Nikon which is a good and traditional Greek name; the 'Aelius' at the front of both names is conspicuous precisely because Greek names are not formulated like this, and it does make me suspicious that there's a freedman at some point in their family tree, particularly since Pergamon had been under the control of the Romans since 133 BC and Galen was alive from 129- c.200 AD that's plenty of time for a Greek family to have been enslaved by Romans, been manumitted and established themselves as wealthy.
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Modern archaeological evidence suggests that Rome was founded by the Etruscans so the Trojan theory is right out. As for the Aeneid, I believe it is seen as an attempt to create an even more in-depth mythological history for the Roman people and to make them seem as they were the chosen people of the gods.
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Why is the number pad on my keyboard opposite of the number pad on my phone?
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> There isn't a definitive answer, but the most cited theory seems to be that the telephone keypad has letters associated with numbers, so 1 2 3 across the top made more sense. Otherwise, the end of the alphabet would be at the top. Calculators, and therefore computer keypads had 1 2 3 at the bottom because it is more ergonomically efficient.
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Computer keypads mimic adding machine keypads, as they were originally only used for offices. It allows the worker to input hundreds of numbers more quickly, because on average, the lower numbers are used more frequently. The lower numbers are closer to you, so you have to move less to input the sums. For most of us, that wouldn't matter, but when you're doing it every day, all day long, for decades, it does make a difference.
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Which is more genetically similar to you: your child, or your sibling?
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According to Wolfram Alpha, a child has a [50% blood relationship fraction](_URL_0_), a sibling only has a [25% blood relationship fraction](_URL_1_). This would suggest a child is more similar than a sibling. On the other hand, they have the same [Coefficient of Relationship](_URL_2_) (0.5), which is probably a much better indicator of what you're asking.
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The children of the respective couples would be expected to look as much alike as siblings do. Genetically, they are equivalent to siblings.
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Angular size test - universal expansion question
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Here's a (fairly long) paper that addresses this: [Angular Size Test on the Expansion of the Universe](_URL_0_) Here is the author's conclusion: > The conclusion of this paper is just that the data on angular size vs. redshift present some conflict with the standard model, and that they are in accordance with a very simple phenomenological extrapolation of the Hubble relation that might ultimately be linked to a static model of the universe.
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This is one of those questions where the answer is just no. Perhaps you could elaborate on why you think angular momentum would cause the universe to expand?
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How did Google blur every license plate on Google maps?
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They do it automatically. Google owns capcha/recapcha. All those times you deciphered numbers and words you were lending human insight to an AI program that identifies numbers/letters in photos. The program scans the photo for those patterns and blurs them out.
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License plates are ID for your car... With that information one (with the right tools or methods) can trace it to your ID ie: name, home address etc etc etc...
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Why some video games allow in game, real time graphics changes, and why other video games require a restart before applying the graphics changes.
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Some changes technically require releasing and re-acquiring a resource from the OS, like resolution changes of the game window. That means the game has to release then re-create all the resources associated with the first one, like the textures and vertex buffers. Other changes require loading different assets, like high vs low resolution textures or models. These shouldn't technically require restarting the program. Likewise for many of the effects settings, like turning on or off SSAA, SSAO, DOF, etc.. That said, it still takes coding effort to add the ability to actually SWAP between different assets. It's often easier to just assume the high-vs-low setting is fixed from the start of the game, and never code the ability to swap our textures and models. Thus, you have to restart the game to get it to load the other set of assets.
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I can think of a couple of easy reasons: * The game relies heavily on hardware that hasn't actually gotten much better since release. If a game was built on technologies that assumed your computer would have a single processor, all of the multi-core processors and fancy video cards in the world won't change much if your single processor cores aren't fast enough. * You're actually emulating the original hardware or software. Maybe you're trying to play a Gamecube game. The emulator makes your computer do a *ton* of extra heavy lifting to pretend it's a console, even if that console wasn't very strong. By way of analogy, the open desert is a simple scene, but if you wanted to build the illusion that someone on the streets of New York had taken a wrong turn and ended up walking across the Mojave Desert, you'd have to pull off one hell of an art installation. Your computer has to sell that illusion close to perfectly, and hope the game it's running doesn't notice any flaws.
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How does compression wear benefit the body?
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It has various uses and benefits. - It can help to stabilize a loose knee joint. - It can reduce sagging if you have big boobs or are overweight. - It can prevent blood build-up in your legs if you are required to sit still for a long time or have circulatory problems.
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It increses the osmolarity of your blood: _URL_0_
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Why is Catalonia trying to leave Spain?
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It's been going on for hundred years or so. Basically they have a different culture, different language, and are wealthy and their taxes subsidize the rest of Spain... And they feel the federal government in Madrid isn't very grateful at all.
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Most of the Spanish money is in Catalonia, so it would benefit them to not having to give it all to the poorer parts of Spain.
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How is energy conserved in negative resistance components?
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They have negative differential resistance. Unlike normal ohmic devices, as voltage goes up, resistance goes down. They don't generate energy.
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It depends on context. If you have some process that involves energy, like a chemical reaction, negative energy often represents the amount of energy *input* necessary for that process to take place. Another example is atomic or nuclear binding energy, which is often treated as negative. For instance, the inner electrons of the gold atom have around 80 keV of binding energy. If a 90 keV photon knocks one of those electrons out, it is emitted with 90 + (-80) = 10 keV of kinetic energy.
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Why are graves 6ft deep?
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That was found to be the depth necessary to prevent animals from picking up the scent and digging for food.
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Obviously different cultures have different traditions, but the typical grave is 3ft x 8ft. There have been about 108 billion people that have ever existed on the planet. That means all the dead people throughout all of history could be buried in the area of about: 2.6 trillion square ft = 92,975 square miles = 240,805 square km That's about the size of Michigan or Portugal. There's plenty of space on Earth for the dead. Once someone has been dead for hundreds or thousands of years, you can just reuse the space in most cases. It's customary for Indians of the Hindu religion to cremate the dead, and their ashes are commonly washed away in a river.
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Why is it that Muslims are often hesitant to condemn other Muslim terrorist organizations?
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Just last week there was a protest at 2000 mosques in Germany by Muslims and Muslim groups, condemning IS. Furthermore, plenty of normal Muslims see Islamic extremist groups as being so far away from their brand of Islam, that they feel no connection to them at all. The vast majority of Christians in America feel no reason to distance themselves from the Westboro Baptist Church or the terrorists who bomb abortion clinics and murder doctors. They see the relationship of just happening to share the same religion as being unimportant. Similarly, many Muslims don't feel any need to distance themselves from al-Qaeda and IS and others because the only thing they have in common is sharing the same religion, a religion of over 1.5 billion people. Think about it. If you're white, you don't feel the need to make an extra effort to distance yourself from Nazis and the KKK, right? Because they're so far away from you, and the only thing you have in common is the color of your skin.
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Islam is a major religion with over a billion followers. I think it's pretty safe to say that most Muslims are just normal people without any particular violent intentions. So you could say they are often misunderstood because many people demonise Islam. "Jihad" is a concept in Islam which roughly translates as "struggle". Some people interpret this as an internal struggle to resist sinning. Other people interpret this as a violent struggle against people they deem to be unbelievers (which often includes other Muslims). This is what people normally mean by Jihadists. Al-Qaeda is a Jihadist organisation. However like most supposedly religious conflicts, the actual reasons they fight are much more than just difference in religious beliefs. It's also political and the desire for power.
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What brought forth the double Slit Experiment? Why or what theories was it meant to test, and how did those Ideas form?
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Thomas Young did this experiment around the year 1800 and demonstrated the wave nature of light, superceding Isaac Newton's ideas about corpuscular particles of light. He may have been motivated by similar phenomena that are present in wave pools, where water waves can interfere with each other.
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With the double slit experiment, the experimenter will use a laser to create the photons aimed at the slit. With a laser the number of photons being generated determines the intensity of the light and it's related (within limits) to the energy being supplied to the laser. So they can dial down the power supplied to the laser until the rate of photons being emitted by reduces to the desired level.
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Why does most of the pens have a small hole in the middle of their body?
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It depends on what you mean. The cap on pens tends to have a hole to prevent them stopping people from breathing if they are accidentally swallowed, and also to allow an outlet to stop suction which would otherwise prevent their removal. You might instead mean the tiny hole on the side of a plastic pen body, roughly halfway down the length of the pen. That is a hole to allow air pressure to equalize within the body of the pen. If such a hole wasn't there then as ink was consumed by being drawn through the tip past the ball it would be gradually pulling a partial vacuum within the pen that eventually would result in preventing ink flow. Air might be sucked in around the ball and stop ink from reaching the tip, or even simply pull the ball into the pen tip too tightly to be turned.
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Our body's are able to deform due to pressure. So by increasing the diameter of the hole, more pressure is added to the skin and flesh around it. After each time the cells divide they try to release the pressure
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During Israel's War of Independence in 1948, why did Britain support the Arab nations?
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They didn't. The UK had abstained in the 1947 partition plan vote, officially handed some things off to Israel after independence (though most of the time they simply pulled out before independence, they did do official hand-offs to Israel), and was neutral during the 1948 war.
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The tension between Arabs and Isrealis is seriously long and complex. Basically Britain set up israel as a state for the Jewish people and moved the Arabs living there into Jordan, The West Bank and The Gaza Strip. The Arab people believe this never should have happened and the entire area that was split up by the British should be reunited as the state of Palestine
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Does the existence of the Planck length imply the universe has an underlying "structure"?
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No, it's just a length constructed from physical constants. It is **not** the fundamental distance. The universe is not divided into a grid of planck length cubes.
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A Planck Length is about 10^-35 meters, and the observable universe has a diameter of about 10^27 meters. Which means that one meter is definitely on the lower end of the scale. EDIT: I failed at reading, son_of_kickpuncher fixed things. On a logarithmic scale, one meter is actually slightly above the middle.
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How long does it take Curiosity to transmit images back to earth
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Right now, Mars is about [1.6 AU from Earth](_URL_0_), so it takes light (and radio signals) 14 minutes to reach us from Mars.
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We don't need to go as far as Curiosity or Voyager for that. The GPS satellites are affected by both special relativity (because they're moving quite fast relative to us) and general relativity (because they're farther away from a massive body than we are). The net result is that a clock on board the satellites would tick faster by 38 microseconds per day.
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why do pictures into r/earthporn look better that what I see
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Some of the photos you see are heavily post-processed. The photographer uses software to adjust things like brightness and contrast to bring out details that otherwise wouldn't be as vivid. If overdone, it can make the photo look fake however.
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Instead of a flat cutoff for distance, they gradually step down the resolution the further away stuff gets (notice how in the closer image has clear trees and stuff, while far away it's all just various shades of green). This eases processing burden tremendously. They'll keep the landmarks slightly higher resolution (like the twin peaks shown) in order to make them stand out, but 95% of the landscape is barely more than flat color.
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Why do restaurants conceal prices?
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Theres two reasons I have seen for lack of prices at high end restaurants. One is sending the message "If you are worried about the prices, you shouldn't be eating here". Partially to make their clientele feel superior. The other is a kinda sexist tradition of having a "women's" menu that doesn't list prices and a "men's" menu that has prices. The latter seems to be more prevalent in Europe from what I understand.
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The cost to make the bread sticks or chips is so cheap it hardly effects their profits. And its more likely to draw customers in compared to that restaurant down the street that doesn’t
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Do you expend more energy running on a flat surface than on a treadmill, ignoring wind resistance?
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It's all about reference frames. When you're running on a treadmill set to a speed you are moving relative to the surface of the treadmill's band at that speed. Since the band cycles around and around, you stay in the same place relative to the room, but you are in fact running. Ignoring wind resistance you are expending the same amount of energy as if you were running on a similar, stationary, surface. **TL/DR:** Nope, cause the band simulates you moving as if it were a stationary surface.
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I feel like this question comes up a lot, and the fact is there is very little difference. [This study](_URL_0_) compared oxygen consumption between people running on a treadmill and people running outside. They found that at slow speeds, there is no significant difference between treadmill running and outdoor running. At higher speeds, wind resistance becomes more significant, so a 1-2% incline on the treadmill becomes equivalent to outdoor running.
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Russian Serfdom and American Slavery
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hi! there have been a few questions about the differences between slavery & serfdom; catch up on the previous discussions here: [What did a serf have that a slave didn't?](_URL_2_) [What caused serfdom to gain prevalence over slavery in Europe?](_URL_1_) [Why did slavery and serfdom become illegal?](_URL_0_)
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Slavery, and later serfdom in european nations was condemned in the [Congress of Vienna](_URL_0_) (1815) after the Napoleonic Wars. In this Congress participated the Great Powers of UK, France, Austria, Russia and sometimes Prussia. New World nations, such as the United States and Brazil did not participate in the Congress. If you mean Slavery within mainland Europe, then it became less popular and eventually diminished after Christianity became the predominant religion; [but only towards other christian europeans](_URL_1_) and for this reason, many non-christians such as jews and slavs were traded as slaves, from here comes the word. Serfdom, however, was still legal until many centuries after.
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Can a change in male health/lifestyle affect the outcome of his offspring?
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Yes, your diet affects both your sperm cell count as well as the genomic function of your sperm. Studies have found (using mice) that males with a poor diet had a higher number of offspring with birth defects as opposed to those with a well balanced diet. When the actual sperm cells were studied it showed the sperm did indeed have different epigenetic markers than those from a male with a healthy diet. But males constantly produce new sperm cells. So if you're not planning on having kids soon you don't necessarily need to worry as much. When you decide to start planning for kids it would be best to change your diet well in advanced.
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It really probably doesn't. The lowest observable adverse effect level in rats is about 10x higher than that measured in cases of chronic occupation exposure, which was considered the "worst case" chronic exposure scenario. Those same populations also had biomarkers of fertility measured and no reproductive toxicity was observed. Further, epidemiologically studies of similarly exposed groups did not indicate any detriment to reproductive health. I have no idea what the EU is basing that classification off of beside speculation that is contradicted by multiple lines of experimental evidence.
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Is water truly odorless or are we just unable to smell it?
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what's the difference between "it's odourless" and "we can't smell it"?
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The same reason people "smell rain", we don't actually smell rain, our noses just work better in high humidity. Same reason farts smell more in the shower.
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What exactly is torque and momentum.
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Very early on when learning physics, you should abandon the mindset that you can interpret physical quantities simply by looking at their units. Eventually you'll run into quantities where it's not straightforward or helpful to do so. An example would be torque and work. These quantities both have dimensions of [force]\*[distance], but they are very different physical quantities. Just looking at the units is not enough to understand the difference between them. Anyway, momentum is the product of mass and velocity. So if you have two objects with the same speed and different masses, the one with the larger mass has a higher momentum. And if you have two objects with the same mass but different speeds, the one moving faster has a higher momentum. So loosely you can think of momentum as how "hard" something is moving, or in other words how hard it is to stop. Torque is the rotational analog of force. Forces cause objects to accelerate, and torques cause objects to change the way they're rotating.
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Force is the change in momentum in time or conversely, momentum is the sum lf all forces that have been applied to an object at each moment in time (i.e. the integral of force in time). In some sense it's the "score tally" of the past actions of forces on the object.
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Why is tuna the go-to canned fish when other species cost significantly less per pound?
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Tuna is a very very firm fleshed fish that takes well to preservation. It holds it's shape, texture, and flavor very well. The canning process, which involves pressure cooking at 15psi and temperatures around 250 degrees Fahrenheit, is very detrimental to proteins found in other fish species. You could can any fish species but most of them would turn to an unpalatable mush in the can. Salmon is another fish that can be successfully canned due to it's firmness and keeping properties.
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See tuna are giant fish, they are one of the top predators of the ocean in fact, so these boys get huge. Some get 300+ lbs. what they do is turn it into sushi, and I’m guessing it must’ve been a giant tuna the dude bought. But you can usually get between 3,500 -8,000 dollars per lb of tuna when you sell it as sushi though.
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why don’t we have sprinklers in single family homes in the US?
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It's not worth it A multifamily dwelling is significantly more likely to have a fire than a single family home, the greater likelihood and greater potential damage justifies the increased cost Sprinklers also require regular maintenance to function properly. If you don't drain your sprinklers every few months then they'll fail when you need them. Putting them in a home where you can't ensure maintenance is wasting money as they won't work when needed There are about a thousand house fires per day in the US, there are 126 million homes. If sprinklers cost $10k and a burned down house costs $1M then it would take 34 years to pay back the investment. That's not remotely worth it to insurance companies so they don't push for it
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Because that would be a logical way to limit water. And the govt doesn't work on logic. Besides home use of water is very small compared to irrigation. Something like 90% of the water used by people in CA is by farms and ranches.
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Why does the liquid "white" part of an egg turn into a solid when heated? (when most, if not all other, liquids become less dense when heated)
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"An egg white is about 10% protein and 90% water. It’s the proteins that cause the egg white to solidify when you cook it. Egg white proteins are long chains of amino acids. In a raw egg, these proteins are curled and folded to form a compact ball. Weak bonds between amino acids hold the proteins in this shape—until you turn up the heat. When heated, the weak bonds break and the protein unfolds. Then its amino acids form weak bonds with the amino acids of other proteins, a process called coagulation. The resulting network of proteins captures water, making a soft, digestible gel." [_URL_0_](_URL_0_)
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Water does what you describe, but certainly not everything. The proteins in the egg are denatured by the heat. When proteins get denatured, the bonds they hold with other molecules get broken, and they frantically try to reconnect those bonds. They end up bonding with a bunch of random stuff, EVEN the metal in the pan (which is why eggs are notoriously sticky to the pan), but mostly with the other parts of the white creating the cooked egg texture.
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How does soap help remove bacteria/germs when washing hands?
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Soap contains molecules that act as surfactants in water, which means they lower water's surface tension. This means that things in the water become less sticky, and that includes the bacteria that are sticking to your hands. Surfactants can also successfully dissolve many materials that wouldn't normally dissolve in water at all, or at least not so easily, and this can include even molecules on the surface of the bacteria that are helping them stick, and sometimes even the bacteria themselves. _URL_0_
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Here is a video on YouTube talking about how soaps work _URL_0_ basically one side of the soap molecule grabs hold of oils and the other side grabs hold of water so the molecule is washed away carrying a little bit of oil
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How does soap help remove bacteria/germs when washing hands?
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This is what my high school chemistry teacher told us. We made soap in class. It removes nonpolar molecules like oils from your hands. Oil and water don't mix. Oil has nonpolar molecules. Water has polar molecules. Soap molecules are nonpolar chains with polar ends, so soap allows oil and water to mix thus washing it off your hands.
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Here is a video on YouTube talking about how soaps work _URL_0_ basically one side of the soap molecule grabs hold of oils and the other side grabs hold of water so the molecule is washed away carrying a little bit of oil
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is it possible for Bill Gates to liquidate his assets into cash? Networth: 85.7 Billion
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Unlikely. Much of his assets would be tied in physical properties, intellectual properties, stocks, bonds, etc. To liquidate, he'd have to find a buyer for everything. Now, he almost certainly has a *huge* amount of liquid assets already for various living expenses, and could quickly divest quite a bit if he needed or wanted to. He also certainly has a staff of very highly trained and good accountants and various investment staff that could move mountains if he told them to do so. But, most billionaires do not do much daily tending to much of their fortuen.
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It would be difficult. He'd have to sell a lot of shares, which would normally reduce their value. Once buyers cottoned on to what he was doing, they would all be like "why buy them today, when I could buy them tomorrow for less?" With billionaires, their "estimated worth" is based on their stock portfolios at today's prices. Large stock holders can have a significant effect. So by starting to cash out, he could negatively impact the cash value.
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Why does your vision get out of focus when you stare at something for a while?
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The muscles that control what your eyes focus on relax, which means they aren’t specifically working to look at something. This makes your eyes ever so slightly move, not enough for anyone to notice but enough so that your brain can’t make sense of what each eye sees, and just throws up a blurry image instead. It’s as if your eyes are looking at something off in the distance, even though you’re meant to be looking at something close. Or vice versa.
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ELI5 Answer: Your eyes see things by seeing changes. When nothing changes, we can't see anymore. Complicated answer: Image burn-in. Humans see light as an "excitement" of the cones and rods in our eyes. If we continue to stare at the same image without it changing, the excitement ends even though the image does not. If you stare at anything for a while, you will notice that your peripheral vision starts to fade and eventually your primary vision starts to fuck up as well.
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How come the Roman Empire never expanded into Germany or other Northern European countries?
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Germany, and Northern Europe in general, was a lot of rough terrain full of angry people that didn't have a great deal of utility for Rome. It was marginal agricultural land without much in the way of other resources. Add to that the fact that it was at the extreme end of the Roman logistical chain and it made major campaigns of conquest in the area very expensive for little practical benefit.
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Very few people actually called those from the Holy Roman Empire Romans, and most contemporaries of the Empire indeed considered it to be a primarily Germanic state moreso than anything else. Considering that the Eastern Roman Empire wouldn't have been particularly receptive to anyone else claiming the title of being *the* Roman Empire, there's no reason for them to call folks from the HRE anything but Germans. As for the other way around, very few in the west considered the ERE to indeed be the successor of the Roman Empire following the creation of the HRE and the schism, if not earlier. It was indeed referred to as the Empire or Kingdom of the Greeks, one or the other, for a long while by the west. Interestingly, the Latin Empire (the name of which is a contemporary invention) considered itself Roman, though, despite being founded by western crusaders.
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Why do so many Americans believe in god?
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*gets on knee* America was founded by very religious groups of people from England and other parts of Europe called Puritans. They created a country based on religious freedom because they themselves were so religious. A large part of modern Americans come from these families. Their traditions and customs have become the America we know and hate today? ok? *gets up*
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Probably the same reasons Christian's/Catholic people in North America think Jesus is white.
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Why are nationals laws such as the No Child Left Behind Act not amendments?
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You don't need an amendment for No Child Left Behind because there is nothing in the Constitution that prohibits the Act. If the Supreme Court had said that the law was unconstitutional, there would be a need for an amendment.
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Because the Constitution lays that out and we haven't made an amendment to change it.
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How do seeds determine where's the surface when planted underground?
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The very top of the root is called the root cap. Some of the cells in the root cap have sensors called statoliths that grow towards the pull of gravity. The stem also has a similar mechanism, but in reverse; so it grows upwards
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This is a lot like the chicken and the egg; the seed didn't simply pop out of thin air as your fundie friend would assume. The earliest land plants reproduced with using spores which germinated into small gametophytes and produced sperm. This sperm would swim into the soil until it would find an ovule and form an embryo. This embryo would eventually grow into a sporophyte. Heterosporic plants produced spores of 2 sizes, micro and megaspores. Eventually, a single megaspore would get boxed into its sporangium while growing. The growing spore (now a megagametophyte) is contained within a tough outer protective layer. This is only one way that seeds were formed in plant life. There are several different evolutionary paths that ultimately converged into spermatophytes (seed plants). Source: [Paleobotany and the Evolution of Plants](_URL_0_)
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When did humans first suppose they had a common ancestor with monkeys?
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No, Darwin was the first, because before Darwin, no one thought that any different species could have a common ancestor, because it was believed each species was a discrete, unchanging unit. That is, even though there was Lamarck, who proposed that species could change in appearance somewhat, he did not say that one species could change so much it became a different species, nor that one species might have several populations branch off and become other species. However, the similarities between humans and apes and monkeys were noticed earlier. This is best indicated by Carl Linnaeus, creator of the binomial nomenclature system which we use (with a few adjustments) today to refer to different species. He placed humans and apes together in the same category. Bonus fact: Charles Darwin's grandfather, Erasmus Darwin, translated Linnaeus's works into English.
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You are right about evolutionary questions being answered by observing common patterns and divergences in the brain. It is actively used in modern neuroscience. The lab I used to work in studied neural stem cells in the brains of mice, rats, ferrets, and rabbits. These animals were chose because of the cost of model organisms and for their specific features. Ferrets have the classic lumpy spaghetti looking (gyrencephallic) brains similar to humans but rats and mice do not (their brains have smooth surfaces - lissencephalic). Richard Dawkin's book "The Ancestor's Tail" starts at Humans, then progressively moves backward in time to each of the most recent common ancestor we had with major animal groups and species. I unfortunately do not recall the elephant-human most recent common ancestor, but I remember its in there.
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Is there any physiological difference between a natural nose & nose that has gone through rhinoplasty?
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A nose job essentially rearranges the bones inside your nose. If you hurt your nose, whether or not you've had a nose job, it could heal incorrectly and bones would heal in the wrong spots or scar tissue would push out things that aren't where they're supposed to be. They're essentially the same thing, except the one with the nose job will have a bit of scar tissue where the cuts were made.
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Our primate ancestors switched to an emphasis on vision, specifically amazing colour vision for daytime, over smell, and colour vision is excellent for locating fruit. As for our noses compared to the other great apes, one thing we do that they don't is *run*. Our noses are well adapted for warming air flowing in and retaining moisture from air flowing out, important adaptations for our specialization in long distance running
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Why does soda seem to be less carbonated when it's hot compared to when it's cold?
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A soda appears to be "more carbonated" when it's cold since the CO2 molecules are more thoroughly dissolved in the soda (the solvent), while when a soda is hot, the CO2 molecules are separate from the soda, making it seem 'less carbonated". Such a difference occurs because gases are more soluble at colder temperatures. This occurs due to the fact that at higher temperatures the gas molecules have a greater average kinetic energy, thus enabling them to break the intermolecular forces which keep them dissolved. Also, at higher temperatures gases have higher vapor pressures which makes them less soluble (this is why manufacturers bottle soda under pressure-to keep the CO2 dissolved). This correlation is evident in the ideas gas law (PV=nRT), since increasing temperature also increases pressure.
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Yes, to expand on /r/EnsuingPiracy. 1. Most gasses dissolve better in cold liquid than in hot liquid. This is also why your cup of soda goes flat faster if it's warmer. 2. The amount dissolved is also proportional to the partial pressure of that gas over the liquid. If you have more air pressure, and a higher concentration of CO2 in that air, more CO2 dissolves in the water. 3. The soda can is a sealed, closed environment, that's not entirely full of liquid. There's some equilibrium of how much CO2 (and water vapor, and other vapors) is in the gas pocket, and how much is in the liquid phase. That shifts with temperature, so you can get more CO2 into the liquid phase if you let the soda sit in a cold place for long enough.
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How does matter hold information.
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We assign meaning to a specific state of matter. This can be a position, or an electric charge, or some other property that we can manipulate and measure without damaging it. A computer hard drive uses a powerful magnet to write your 1s and 0s to the disk by changing the magnetic direction of each designated space. A CD uses ridges burned into it by a laser. Imagine you had a pile of rocks and needed to make it "remember" 10110100. You can do this a numer of ways. Draw a line and have rocks on the line mean 0 and rocks above it mean 1. Have two rocks mean 1 and one rock mean 0. Any number of permutations will work, as long as you can remember what means 1 and what means 0. That's basically how we store data, using charge or magnetism or ridge height as our rocks.
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Think of it as a filing cabinet. You open the drawer and you pull out a folder. The folder has nothing at all in it. It is a file with no data. If someone were to ask you how big the file is you would say it had no data. Even though it has no data, there's still a folder there and it still takes up space in the filing cabinet albeit not nearly as much as the file with a hundred pages in it.
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