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The generated torque is perpendicular to the axis of rotation. Since the axis of rotation is fixed by assumption, such a torque can not change the angular momentum about that axis. Dragons flight (talk) 02:44, 11 April 2010 (UTC)[reply]
Quantum entanglement can't be used to transfer information because this would violate relatvity (the data travel, if possible, would be instantanious, which would be faster than the speed of light), that part I understand. Now consider this, imagine two friends, Alice and Bob, each have a box with a particle in it. Those two particles are entangled to one amother and are in a superpositon of being the color red or blue. As soon as one of the two of them looks at their particle, decoherence will occur and the particle will be either red or blue, not both. Not only that but because the two particles are entangled, the other friends particle will become the opposite color. If Alice looks and finds hers to be red, Bobs, even though he hasn't looked yet will be blue. A soon as Bob looks he will find his to be blue and he will know that Alices must have been red. Isn't this a transfer of information? I know that Alice or Bob can't use this to transfer their own information, like one telling the other their favorite kind of pie, because the color that the particles ultimatly become when viewed is random and unpredictable. But still, isn't information still being transfer, when one looks at the color of their particle they immediatly know the color of their partners too. Wouldn't this violate relativity? Could some one please explain to me how that would be possible, am I mssing something?
The way I'd look at it is that they each already had the info on the other, they just hadn't looked at it yet. So, the info didn't travel between the two remote people at all, it was already right there in the box. StuRat (talk) 03:32, 11 April 2010 (UTC)[reply]
I agree...who needs all that funky quantum stuff? Take a matchstick, break it in half and toss each half into a box...give one box to Bob and the other to Alice (at random). Whoever opens their box and sees that they have the head of the match knows that the other person has no head on their half of the matchstick - and vice-versa. That isn't what's happening with the quantum entanglement thing (well, depending on your interpretation of quantum theory) - but the information/communication situation is indistinguishable and no laws are broken in the process. SteveBaker (talk) 03:49, 11 April 2010 (UTC)[reply]
Yeah, in this particular experiment there's nothing going on that's very interesting or problematic. Bell's theorem is that there are ways to measure the entangled particles that can't be reproduced with match sticks, but even then there's no information communicated. The test for that is, can Alice make an arbitrary yes/no decision after she and Bob part company, and then somehow let Bob figure out what her decision is faster than light. It's still impossible. Rckrone (talk) 05:25, 11 April 2010 (UTC)[reply]
Welcome to Wikipedia. Your question appears to be a homework question. I apologize if this is a misevaluation, but it is our policy here to not do people's homework for them, but to merely aid them in doing it themselves. Letting someone else do your homework does not help you learn how to solve such problems. Please attempt to solve the problem yourself first. If you need help with a specific part of your homework, feel free to tell us where you are stuck and ask for help. If you need help grasping the concept of a problem, by all means let us know.
You might find Snell's law a helpful article to start at. Your first equation looks like a common representation for the result of a double-slit experiment. Technically, any of these equations can mean anything, because you have not defined what the variables represent - but most of them are standard-form, standard-notation equations for some elementary optical physics. Nimur (talk) 02:44, 11 April 2010 (UTC)[reply]
And your second equation looks like uncommon notation for the frequency of a pendulum. Again, it can mean anything if you don't define v, T, and μ. Nimur (talk) 02:50, 11 April 2010 (UTC)[reply]
You might be better off looking for more information at wherever you got those equations from. They all look like items from the waves and optics chapter of an introductory physics text. However, the symbols used in equations often vary from text to text and course to course. We could make educated guesses about what they each mean, but to be certain you'd need to know where they came from. Dragons flight (talk) 03:36, 11 April 2010 (UTC)[reply]
Is there a way to create a temporary "barrier" (that does not use matter, but energy or light) that would cause all light particles that contact it to reduce in frequency —for instance, turn visible light into infrared rays, or infrared into microwaves.
You could use gravitational redshifting. Gravitational fields contain energy, though it's not like you can just make it like you can light. Also, any form of energy will have a gravitational field, so technically that works. This only will reduce the frequency going in one direction, and will increase it if it goes the other way. — DanielLC06:06, 11 April 2010 (UTC)[reply]
Also, there is no such thing as energy that exists by itself without associated matter or light. So by asking for a barrier made of energy but not matter you already reached the impossible, even without trying to reduce the frequency. Ariel. (talk) 07:26, 11 April 2010 (UTC)[reply]
In a certain sense, you can do it with matter. Just let the light heat up an object; it will then re-radiate light at a frequency, or rather a spectrum of frequencies, determined by its temperature. If you don't let it get too hot, the bulk of that radiation will be at a lower frequency than the incoming light.
This might sound like a strange idea but I thought I'd ask about it anyway... If you were to fill the craters of the world's volcanoes with water, what would happen? Would the cap of the volcano be kept cooler and therefore possibly stave off an eruption? And if there was a violent eruption, would the water either A) decrease the amount of ash that was ejected into the atmosphere or B) be vaporized and therefore provide the moisture necessary for that ash to rain back down sooner? Dismas|(talk)03:32, 11 April 2010 (UTC)[reply]
Well, if it's an active volcano, the water will likely boil away faster than you can pump it in...but eventually, I suppose, you'd make a thin insulating crust over the lava pool that might allow you to fill things up a bit. But the power of a typical volcano isn't going to be suppressed that way - either you'd end up with an explosion instead of a slow oozing of lava - or you'd maybe cause the lava to force it's way to the surface via some other route. I don't think you have a hope in hell of shutting the thing down. SteveBaker (talk) 03:40, 11 April 2010 (UTC)[reply]
Explosive volcanic eruptions (as opposed to comparatively gentle flow of lava) are directly correlated with the amount of water in the magma: more water, more explosion, since the water flashes to steam when pressure is released. Water on top of the magmatic mass would exert little cooling effect (there are submarine eruptions all the time, although explosive eruptions are suppressed in deep water by pressure). See Phreatic eruption for a discussion of the role of water in volcanism. On land, water + magma = boom. Acroterion(talk)03:48, 11 April 2010 (UTC)[reply]
The OP should keep in mind that the part of a volcano you can see (the mountain bit) is actually only a small part of the actual volcano. Think "iceberg". The actual structure is many orders of magnitude larger than the mountain you see at the surface; and the processes that cause an eruption occur many miles underground, and nothing you can do at the surface is going to affect it. It would be like trying to stop a bullet by placing a thimbleful of water into the barrel. --Jayron3203:51, 11 April 2010 (UTC)[reply]
Wet ash probably will not travel as far as dry ash. The amount of ash will be the same, but it will fall down faster. Ariel. (talk) 06:51, 11 April 2010 (UTC)[reply]
I doubt even that. Any water in the caldera will be vaporized in seconds, and the mass of water that any such caldera would contain would be insignificant compared with the mass of ash. Perhaps for the first few seconds of an eruption, one might see such a wet-ash effect (and that's a very small maybe, I still doubt it will have any effect), but for the bulk of the eruption, there will be zero effect. --Jayron3212:06, 11 April 2010 (UTC)[reply]
Enough water can make them better, like if they are under miles of water. Volcanoes down there rarely pose problems for those of us on the surface. StuRat (talk) 00:40, 12 April 2010 (UTC)[reply]
The Cumbre Vieja volcano is already partly filled with water, increasing the risk for a potential collapse of its western flank. The Erta Ale volcano may have water surrounding its base due to sea level rise and this may initiate the rifting in the area. There are also active subglacial volcanoes underneath the West Antarctic ice sheet such as the one under Pine Island Bay, which if they erupt could have an effect on global sea levels. ~AH1(TCU)00:38, 15 April 2010 (UTC)[reply]
I agree - the answer is "No". If you absolutely, utterly have to find a way to do it (eg, for quasi-believable fictional purposes) then I recommend the idea of using the Large Hadron Collider to make a particle called a strangelet - which has the peculiar property of changing anything it touches into another strangelet. This would result in a chain reaction that would result in the entire planet turning into a blob of strangelets about the size of a golf ball over the course of just a few minutes. However, the idea that strangelets actually exist is highly speculative and controversial - the idea that you could create one using the LHC is even more speculative and even less likely - and the idea that they would be stable enough (when not at the core of a large neutron star) to remain stable for long enough to achieve the destruction of the earth is yet more speculative than that. But, it's not currently known to be definitely impossible - and for the purposes of sci-fi, that's usually good enough! SteveBaker (talk) 14:03, 11 April 2010 (UTC)[reply]
Is it possible to change the orbit of a large comet using a space probe so that it can collide with earth? --Galactic Destroyer (talk) 16:04, 11 April 2010 (UTC)[reply]
Changing the trajectory of asteroids has been suggested before, usually to avoid an impact event but I don't see why it couldn't be used to create one as well. But even if you were to turn a near miss into an impact using a method like this, it wouldn't blow the world into little pieces. You'd need a huge body to do something like that, something closer to the size of the moon than the size of a comet, and I don't think it's feasible to make the moon smash into the earth with current technology. TastyCakes (talk) 16:26, 11 April 2010 (UTC)[reply]
Even the moon would not be enough. It might hurt people, the the earth itself will still be there in one piece. You would need something much larger, like venus. Ariel. (talk) 18:11, 11 April 2010 (UTC)[reply]
"Hurt people"? I'm pretty sure if you drop the moon on the Earth, you'd boil most of the seas and atmosphere and kill all macroscopic life. But you're right, the chunk of rock would mostly remain in one piece unless you somehow gave the moon far greater velocity than it has now. Dragons flight (talk) 18:20, 11 April 2010 (UTC)[reply]
It would have turned the Earth back into a molten ball. To actually permanently blast the Earth into pieces that would never re-accumulate to form a new Earth, the object would have to be going a substantial portion of the speed of light, I'd think. StuRat (talk) 19:18, 11 April 2010 (UTC)[reply]
Would that be enough to blast all the parts of the Earth out of the solar system, in different directions ? Otherwise, if they are all left in about the same orbit the Earth has now, I'd expect them to come back together over million or billions of years. StuRat (talk) 22:51, 11 April 2010 (UTC)[reply]
Well, first, if the earth was blown into little bits, which over the next 1,000,000,000 years reformed into a planet, I would argue that it is not the same planet, especially since there would be no one left who could differentiate. Googlemeister (talk) 19:16, 12 April 2010 (UTC)[reply]
Yes. I just finished testing a Earth Destroying Weapon yesterday and it did a very good job of the portion of the Earth which I used to test it. I need more money though to make it large enough to destroy the whole Earth. You can make an offer to lease it on my talk page and if I accept I'll provide you with the email address for my PayPal account. CHeers.
According to our article on the gas neon, it is a common element in the universe. So, here's a question. Let's assume you have a planet that has an atmospheric mixture of 60% nitrogen, 20% neon and 20% oxygen at say, about 0.95 atmospheres at datum level. Would there be any impediment to human life in such an atmosphere? We're assuming "liveable" temperatures here. Googling suggests that neon poses no problems re: toxicity at Earth-like conditions, but I thought I'd ask. Thanks in advance. Peter Greenwell (talk) 09:07, 11 April 2010 (UTC)[reply]
Neon is entirely inert; even moreso than nitrogen. I suspect there would be little differnce, vis-a-vis breathability with any atmosphere that was about 20% oxygen and 80% inert gases, regardless of the identity of the inert gases, be they argon, neon, or nitrogen. --Jayron3212:03, 11 April 2010 (UTC)[reply]
However, some articles related to trimix find the presence of various amounts of nitrogen (and alternative non-oxygen gases) has some effects on, for example, High pressure nervous syndrome. Those all seem to be about reducing negative effects seen at high pressure, so it's not clear if the studies are relevant to nitrogen-content at normal atmospheric pressure (i.e., where we have evolved to live, and where our "normal" for health baselines is). DMacks (talk) 17:42, 11 April 2010 (UTC)[reply]
Right: nitrogen's not quite inert: see for example nitrogen narcosis. Interestingly, that article suggests that helium and neon are the only gasses that don't have a narcotic effect at high temperature pressure. I guess the narcotic effect is due not to the chemical reactivity of the gas (as oxygen toxicity is), but rather to the physical process of the gas dissolving in body tissue at high pressures. Huh, I learned something new today. Buddy431 (talk) 20:43, 11 April 2010 (UTC)[reply]
That should be high pressure in the second sentence. Argon#Safety does not mention its narcotic properties, should it, or is it so close to oxygen and nitrogen that it doesn't really matter? --NorwegianBluetalk21:30, 11 April 2010 (UTC)[reply]
Right you are (fixed now). As for Argon, I don't think that it's typically breathed under high pressure, (as nitrogen or oxygen might be, in SCUBA equipment), so there's probably not much of a need to state that it has narcotic effects at high pressures. If the nitrogen narcosis article is right, that nearly every gas has this effect at high pressures, then it seems sort of pointless to list it for every gas, and should probably be only listed for gasses that might be breathed at high pressure. Buddy431 (talk) 22:45, 11 April 2010 (UTC)[reply]
Usually, they breathe helium and oxygen - but that makes their voices squeaky - so in some applications, they use neon and oxygen because the neon has more similar density to nitrogen and hence does not distort voices noticably. Neon is more expensive than helium though - so not many divers use it. In either case, the entire point of doing it is because those gasses DON'T dissolve in the body tissues when under pressure to the extent that nitrogen does - and hence avoids most of the problematic depressurization issues. SteveBaker (talk) 13:32, 12 April 2010 (UTC)[reply]
Nitrogen narcosis isn't a depressurization issue (the bends are though). Nitrogen narcosis happens at depth due to... well the articles not real clear on it, but it doesn't involve gasses coming out of solution, as the bends do. Buddy431 (talk) 14:16, 12 April 2010 (UTC)[reply]
(edit conflict)I would think lemon juice (namely the citric acid) would make the soil somewhat more acidic, which would benefit any plant that likes acidic soil. But that would depend on the soil pH before you add the lemon, the amount of lemon you had and so on. I would suspect one slice wouldn't have much effect since they're not that acidic, but that's just a guess. TastyCakes (talk) 16:20, 11 April 2010 (UTC)[reply]
Note that the lemon slice will soon rot, and may give off a strong smell once it gets fuzzy. For this reason, you may do better to squeeze out some juice and discard the slice, at least for indoor plants. StuRat (talk) 16:25, 11 April 2010 (UTC)[reply]
"Invariably"[citation needed]--can you be more specific about what sorts of stains you are talking about--the effect of a water-based material spreading out on the surface and/or the water (and possibly stuff it in) altering the surface itself could be two different effects. For example, if I spill water on a not-water-proof painted surface, the water can dissolve the paint at the point of the drip and carry it outward as the drop expands until the water evaporates. Repeat, repeat, repeat, and now the wood winds up bare in the middle and the extra paint spread out from it. DMacks (talk) 17:26, 11 April 2010 (UTC)[reply]
I can think of several possible reasons:
1) Miniscus. Since water droplets on non-absorbent materials are curved, there's more surface area near the edges, so, when they dry, those items carried on the surface of a drop (like dust and pollen) accumulate more on the edge than in the middle.
2) Diffusion. Since the water is pulled by capillary action along an absorbent material, and pulls the contaminants along with it, they tend to continue to be carried along until the water dries, and the stain thus forms at the boundary where the drying occurs.
3) Perception. In the middle you are comparing it with areas stained nearly the same amount, while, at the edge, you're comparing it with unstained areas. Thus, the edge appears to be stained more, by comparison. StuRat (talk) 17:36, 11 April 2010 (UTC)[reply]
The stain dries from the edges first. As it does, water plus dirt is pulled toward the edge to equalize the wetness. This causes more dirt to be at the edge vs. the middle. Ariel. (talk) 18:07, 11 April 2010 (UTC)[reply]
Hi everyone, I know what systolic and diastolic blood pressures are but I'm not really sure what are the different factors that increase/decrease systolic and/or diastolic blood pressure. Can anyone explain to me what the factors are and a little about the mechanism behind it?
Aw, come on. We could at least tell the questioner that the word s/he seeks begins with the same four letters as "homework", and that our article Life would be a reasonable place to start looking. --NorwegianBluetalk21:07, 11 April 2010 (UTC)[reply]
Were there fat people around ~20,000 years ago? I had the impression nutrition was pretty poor for everyone, but Venus of Willendorf suggests other wise. Would she have to be a queen or something, while her minions ran around desperately trying to gather/kill enough food to feed her? Aaadddaaammm (talk) 20:10, 11 April 2010 (UTC)[reply]
From the article, clearly we don't know for sure what it was for (it's not like it came with a book of instructions). As the article notes "not a realistic portrayal but rather an idealization of the female figure"; I guess when you live in a world with naught but skinny nomad women, that's what you'd idealise. Thinking it's meant to actually display a real person is like some future people discovering images of Jessica Rabbit or Jordan and mistakenly thinking such forms could actually exist. -- Finlay McWalter • Talk20:26, 11 April 2010 (UTC)[reply]
Lol, that’s really funny when you think about it! It's not like the women you see in magazines these days are "realistic depictions of real people" either! 2000 years from now they might dig up some playboy magazines and wonder if anyone ever actually looked like that. :) Vespine (talk) 04:12, 12 April 2010 (UTC)[reply]
"Professor, it appears that AIDS was more wide-spread than we thought, as clearly all the women in this magazine are suffering from some terrible disease. Yet, somehow, they still managed to smile. Weren't our ancestors brave ?" StuRat (talk) 00:34, 12 April 2010 (UTC)[reply]
Things may have changed since the last time I read anything about this, but I'm pretty sure the standard interpretation of Venus of Willendorf and similar figurines is that the depicted females are pregnant and symbolize fertility - of humankind, of earth and nature in general or both. Of course, she's also rather plump and well-fed, which was probably the ideal back then, as pointed out by others. Again, as far as I remember, Venus of Willendorf is not believed to reflect a society with social stratification but a relatively primitive and egalitarian one.--91.148.159.4 (talk) 15:23, 12 April 2010 (UTC)[reply]
To answer aaadddaaammm's first question, there was certainly no agriculture in Europe, or anywhere, in 20 000 BC. There may have been extremely limited social stratification (i.e. people who fight better get to eat more, or something), but agriculture and "civilization" won't arise until after 10 000 BC. Buddy432 (talk) 16:58, 12 April 2010 (UTC)[reply]
Probably, there were occasional periods and areas of relative well-being, and during those periods and in those areas people stuffed themselves - until they became plump, if given the chance. Then they starved again, then they stuffed themselves again, etc.. Fortunes change. There were always reasons for some clans to have more success as hunters-gatherers than others, and hence to become fatter.--91.148.159.4 (talk) 18:53, 13 April 2010 (UTC)[reply]
These are newbie questions, and I would appreciate answers to them, because they pertain to a piece of writing I'm working on.
How does the coriolis effect work on the Thermohaline Current? I understand what it is, roughly, and I think it would determine what direction the current would turn if it hit a coastline, but I'm not sure.
There's a type of wind that comes down from high mountains as the air there cools slightly and falls, and warmth is carried along. What is this type of wind?
Assuming that one were to take a mountain area where there was such a wind, would increasing the absorbent ability of the rock (i.e. making it blacker) increase the heat of the area and increase the heat and strength of the wind?
Has there ever been a verifiable recorded case of a human being swallowed whole by a whale, but managing to get out somehow and living to tell the tale? Except for Johah, I mean - as with many stories from the Bible, there can be considerable doubt as to whether it happened exactly as described, or if it even happened at all (and isn't just a legend or a metaphor for something else). Did it ever happen during the days when whaling was far more widespread than it is now? --95.148.104.124 (talk) 21:44, 11 April 2010 (UTC)[reply]
The only recorded story that I've heard is the James Bartley story, which is purely fiction. It has been repeated with a different character replacing James Bartley to make it a local legend to various seaports - which makes it even more fiction. -- kainaw™22:16, 11 April 2010 (UTC)[reply]
Let's think for a moment about the conditions in the whales' stomach. There is no air there. The liquid is hydrochloric acid. It's an environment that's highly tuned to digesting the very stuff your body is made of. It's REALLY hard to imagine you surviving in those conditions for more than maybe 30 seconds to a minute. So - your only chance is to hack your way through several feet of muscle, fat and super-tough blubber. Seems astronomically unlikely to me. SteveBaker (talk) 02:35, 12 April 2010 (UTC)[reply]
Answering the question about whale physiology, some guy did a LOT of research into the James Bartley story (I'm sure the guy's name/research is easy to track down on Google). I remember reading a synopsis of his story in which a biologist stated that the largest whales could swallow a man whole, but most whales could not. As for the fake story, they understand about the air and digestion. The claim was that James was swallowed while the whale was being brought aboard a whaling ship. So, he was only in there for a short time - but was still partially digested and required medical treatment. The guy who did the research tracked down the ship he supposedly fell from and talked to both the captain and his wife - both refuted the story. He went to the hospital which supposedly gave him treatment. All there refuted the story. He checked the ships logs, which had no record of a James Bartley. He even went further, but honestly, is there any reason to believe that a while swallowed a man who lived through the process? -- kainaw™02:57, 12 April 2010 (UTC)[reply]
As to whether it would be possible for a whale to even swallow a human whole, probably not. Most toothed whales like dolphins and orcas aren't nearly large enough to do so, and baleen whales, which look large enough, aren't apparently built right. Blue Whale#Size indicates that, while their mouths are large enough to hold something like 90 metric tonnes of food and water, their throats are only large enough to fit an object the size of a "beach ball". I suppose, if it was a small man, and if he were oriented just right, he could wiggle down there. --Jayron3204:18, 12 April 2010 (UTC)[reply]
"...your only chance is to hack your way through several feet of muscle, fat and super-tough blubber." - or be vomitted up by the whale, which could conceivably happen in the required time frame (assuming that you could be swallowed in the first place). Mitch Ames (talk) 09:14, 12 April 2010 (UTC)[reply]
They do seem to spit out unwanted items. In one of the David Attenborough specials, they were filming the whales make a bubble net and then lunge for the fish at the surface. Birds were also diving for the fish, and one got swallowed. The whale spit it out, and it survived. The divers filming underwater hoped the same would happen if they got swallowed, but were lucky enough to not have to test that theory. Note that "swallowed" here probably just means "taken into the mouth", not the stomach. StuRat (talk) 16:01, 12 April 2010 (UTC)[reply]
A lot of people believe a lot of things that aren't true...it doesn't make them true. But I don't think we're seriously objecting to the idea that someone might somehow be swallowed by a whale - the issue is how they might possibly survive to tell the tale. SteveBaker (talk) 17:59, 12 April 2010 (UTC)[reply]
Well, the way I see it, you have three options if actually swallowed by a whale:
Make the whale vomit
Pull out your knife/machete (presuming that you have one) and try to cut your way out
Climb back up its oesophagus and out the mouth
2. and 3. may also work to elicit 1. I don't suppose that the whale would enjoy having a signal flare set off in its innards either.
Are you certain that there's no air present in the stomach of a whale, Steve? I mean, I know literally nothing about the digestive processes of Sperm Whales - but I always thought that stomachs in general had some sort of (presumably fucking foul) air/contents boundary. Do whales digest food quickly - or are they more like snakes, in the sense that food can sit in their stomachs for a couple of weeks before it is broken down? --Kurt Shaped Box (talk) 18:20, 12 April 2010 (UTC)[reply]
Why would there be air there? Whales swim at great depths - air in their stomachs would be a liability - if it got in there somehow, they'd probably just belch it out. If there were gases in there, I doubt it would be very breathable anyway. SteveBaker (talk) 02:45, 13 April 2010 (UTC)[reply]
Being mammals, I'd expect them to have a reasonably fast digestive system, like ours. But, of course, only the first stage of digestion is in the stomach, with the intestines doing most of the work. StuRat (talk) 01:22, 13 April 2010 (UTC)[reply]
You could buy a little time by hacking your way from the stomach into the whale's lungs - then you'd have enough air for several hours while you decide what to do next. Mitch Ames (talk)
Still - you arrive there - it's dark, there no air, you don't know which way is up and which down, your skin is probably burning from the pH 1 or 2 acid that's all around you. I doubt the stomach walls are staying still - so you don't have any kind of good footing. You probably got pretty roughed up by the whole business of being in the water, grabbed an swallowed. You'd be far too disoriented to make a serious plan. Get real - you don't stand a hope in hell! SteveBaker (talk) 02:45, 13 April 2010 (UTC)[reply]
How about a Finding Nemo option where the individual were just inside the mouth cavity for a short period. This seems a lot more feasible. I believe in The Holy Bible, but you can't take some things literally. It is a physical impossibility that Noah harvested 2 of every terrestrial species. If Noah had that technology, ability to travel, and knowledge, he also could have orbited the earth in an awesome space station. Humankind today couldn't even come close to achieving this.--FUNKAMATIC ~talk03:28, 14 April 2010 (UTC)[reply]
Hi. In a recent lab I had, I had to determine the contents of a mystery box. I was told that there were two impedances, Z1 and Z2, and that in total there were 3 circuit elements (they can either be a resistor, capaictor, or inductor). Now, I was able to short the Z2 element, which allowed my to isolate Z1. I then added a resistor in series with Z1 and ran an alternating current through the circuit (resistor is between input generator and Z1. What I saw was a low-pass filter. I reasoned that this meant that there would be a capacitor in Z1, because an RC circuit produces a low-pass filter when run through an alternating current (the voltage was measured across Z1). Looking more closely, I saw that at high frequencies, the voltage died down to zero, but at low frequencies the voltage wouldn't reach the voltage of the generator (as would be expected if Z1 were just a capacitor), but a value a bit lower than that.
When I was doing the lab, it struck me as very obvious that this implied that Z1 consisted of a capacitor in parallel with a resistor. The problem is that I forget why. Can anyone help lead me in the right direction? Thanks. 173.179.59.66 (talk) 22:13, 11 April 2010 (UTC)[reply]
What is the least common cause of death in human history? Of course, every death is unique, with many just a variation on the same official cause, but what is the least common official cause. To qualify it further, if every human death had resulted in an autopsy, what would be the least common cause recorded on the autopsy reports. Thanks JohnnyShadow (talk) 22:38, 11 April 2010 (UTC)[reply]
Such a claim would be impossible to prove or conjecture on. There are likely thousands or millions of "unique" deaths, depending on how you define the "cause" of death. The graph of "cause of death" in the modern world has large numbers dying of things like heart disease and cancer and infectious disease and then a VERY long tail where all of the randomly weird causes of death lie. For example, there have been only been three people in the history of the world to be killed by exposure to the vacuum of outer space, see Soyuz 11. --Jayron3223:09, 11 April 2010 (UTC)[reply]
Which also illustrates the problem of counting. Three cosmonauts died of exposure to outer space, but if you instead labeled those deaths as "asphyxiation" then it would be relatively common. At least one person has died by driving a big rig off the S-curve in the Oakland Bay Bridge, while many people die in traffic accidents. Many deaths can appear unique, or nearly so, if you describe them in enough detail, but there is nothing particularly special about that. Dragons flight (talk) 23:35, 11 April 2010 (UTC)[reply]
And some people would argue that we all die from the very same thing, lack of oxygen to the brain, and there are no unique deaths. Dismas|(talk)23:36, 11 April 2010 (UTC)[reply]
They'd very clearly be wrong. A brain reduced to a pulp by a bullet or smashed into a jelly in an explosion needs no lack of oxygen to be a very dead thing. --Tagishsimon(talk)00:15, 12 April 2010 (UTC)[reply]
Indeed. Almost all people die from lack of oxygen to the brain. A few do die from physical trauma to the brain. --Tango (talk) 00:58, 12 April 2010 (UTC)[reply]
Not to mention that one can die from excess oxygen to the brain, as well. Like my old electronics professor said, "if it doesn't work, that means either there is a contact where there shouldn't be one, or there is no contact where there should be one". No, seriously, lack of oxygen to the brain is not the only ultimate cause of death. --Dr Dima (talk) 00:28, 12 April 2010 (UTC)[reply]
I don't think oxygen toxicity directly causes death very often. When it does, I think it is more likely to be due to damage to the lungs resulting in a lack of oxygen to the brain than the actually effects of too much oxygen in the brain (which are things like nausea and seizures). --Tango (talk) 00:58, 12 April 2010 (UTC)[reply]
That depends on how you define it. Homicide is a fairly common cause of death, and death from radiation sickness is a bit less common, but not exactly rare. If you define that more broadly as death from exposure to radioactive elements, then millions have probably died from lung cancer due to exposure to radon gas. StuRat (talk) 01:12, 12 April 2010 (UTC)[reply]
Biology should be our concern. Life being a biological process, we should want to concern ourselves with that which interrupts that process, resulting in death, especially in those cases where the person is young and/or otherwise healthy. Cause of death can probably be understandably less clear in old age and/or otherwise poor overall health involving many weaknesses in the biology supporting life. Bus stop (talk) 01:30, 12 April 2010 (UTC)[reply]
It's hard to beat being killed by a meteorite impact, although the only recorded example involves a dog rather than a human. But my favorite story is of the Greek playwright Aeschylus, who was supposedly killed by a tortoise dropped on his head by an eagle. (Lots of people think that story is ridiculous, but it's actually pretty common for birds to drop animals with shells onto rocks to break them open, so I don't see why it couldn't have happened.) Looie496 (talk) 18:25, 12 April 2010 (UTC)[reply]