lehpron
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Re:Physics question
Thursday, February 03, 2011 4:11 AM
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Abiabatically (meaning no heat transfer in either direction) and isentropically (meaning it is a reversible process with no losses, i.e. no friction or efficiency differences), while a gas is being evacuated from a tank, the temperature of that gas will drop (if you cut the pressure of air inside a tank in half, the temperature can be about 12% less). Think about how we get temperatures: molecules in motion transfer their knetic energy to poential energy, this builds up with millions of them and the reactions get stronger when they are warmer because they move faster. Sure if nothing is bouncing around, we detect zero, but that doesn't mean it is. I can vacuum seal a jar of nuts, but they won't suddenly freeze even though there isn't that much air in there (although the air around the jar could be room temperature and therefore not adiabatic). Farther down the thermal scale, we can say the measurement itself is a statistical probability of running into a random cloud of molecules that haven't impacted out thermal probes yet because they are moving slowly. So is it zero until then?  It clearly wouldn't be uniform to assume actual distributed temperature if we decide to move the probe to different areas of what we think is a vacuum. Pure vacuum would be deep outerspace, I think, where there is nothing as we've defined. What is that temperature reading? I guess it is assumed zero until you run into more particles.
post edited by lehpron - Thursday, February 03, 2011 4:18 AM
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Nex_Lupus
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Re:Physics question
Thursday, February 03, 2011 4:13 AM
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tl;dr but lephron sounded the smartest he wins XD
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brcromer
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Re:Physics question
Thursday, February 03, 2011 4:35 AM
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ShurikenTenshi
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Re:Physics question
Thursday, February 03, 2011 9:58 PM
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 12G-P5-3953-KR 6/30/2021 6:23:47 AM PT YES! 10G-P5-3899-KR 6/23/2021 6:01:36 AM PT No 10G-P5-3889-KR 6/23/2021 6:01:12 AM PT No 24G-P5-3979-KR 6/23/2021 6:00:45 AM PT No 12G-P5-3968-KR 6/3/2021 8:15:04 AM PT No 10G-P5-3898-KR 12/17/2020 7:55:06 AM PT No
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Rudster816
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Re:Physics question
Thursday, February 03, 2011 10:11 PM
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lehpron Abiabatically (meaning no heat transfer in either direction) and isentropically (meaning it is a reversible process with no losses, i.e. no friction or efficiency differences), while a gas is being evacuated from a tank, the temperature of that gas will drop (if you cut the pressure of air inside a tank in half, the temperature can be about 12% less). Think about how we get temperatures: molecules in motion transfer their knetic energy to poential energy, this builds up with millions of them and the reactions get stronger when they are warmer because they move faster. Sure if nothing is bouncing around, we detect zero, but that doesn't mean it is. I can vacuum seal a jar of nuts, but they won't suddenly freeze even though there isn't that much air in there (although the air around the jar could be room temperature and therefore not adiabatic). Farther down the thermal scale, we can say the measurement itself is a statistical probability of running into a random cloud of molecules that haven't impacted out thermal probes yet because they are moving slowly. So is it zero until then? It clearly wouldn't be uniform to assume actual distributed temperature if we decide to move the probe to different areas of what we think is a vacuum. Pure vacuum would be deep outerspace, I think, where there is nothing as we've defined. What is that temperature reading? I guess it is assumed zero until you run into more particles. There is no such thing as a pure vacuum. The "vacuum" of deep space still has a tiny amount of matter in it, which temperature is about 3k. In theroy, a pure vacuum has no matter inside of it at all. Since there is no matter, there is no molecular movement, which is temperature. Since there can not be a pure vacuum in real life, any actual 'vacuum' will have a temperature.
[22:00:32] NordicJedi: the only way i can read this chatroom is if i imagine you're all dead 
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lehpron
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Re:Physics question
Thursday, February 03, 2011 11:10 PM
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I think we're getting into an equal level of sematics, but then i did say, Pure vacuum would be deep outerspace, I think, where there is nothing as we've defined. Note bold, deep as in so far out there that there is no particle motion and the probability of detecting temperature drops to zero as well, and "nothing as we've defined" unfortunately can even mean more that what your or I think are obvious. I meant it as a statistical zero, that like temperature, the chances for anything higher is pretty close to zero. But in general, I always cover my ass in my comments.
post edited by lehpron - Thursday, February 03, 2011 11:15 PM
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brcromer
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Re:Physics question
Thursday, February 03, 2011 11:22 PM
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vlad01
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Re:Physics question
Saturday, February 05, 2011 6:56 AM
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lehpron Abiabatically (meaning no heat transfer in either direction) and isentropically (meaning it is a reversible process with no losses, i.e. no friction or efficiency differences), while a gas is being evacuated from a tank, the temperature of that gas will drop (if you cut the pressure of air inside a tank in half, the temperature can be about 12% less). Think about how we get temperatures: molecules in motion transfer their knetic energy to poential energy, this builds up with millions of them and the reactions get stronger when they are warmer because they move faster. Sure if nothing is bouncing around, we detect zero, but that doesn't mean it is. I can vacuum seal a jar of nuts, but they won't suddenly freeze even though there isn't that much air in there (although the air around the jar could be room temperature and therefore not adiabatic). Farther down the thermal scale, we can say the measurement itself is a statistical probability of running into a random cloud of molecules that haven't impacted out thermal probes yet because they are moving slowly. So is it zero until then? It clearly wouldn't be uniform to assume actual distributed temperature if we decide to move the probe to different areas of what we think is a vacuum. Pure vacuum would be deep outerspace, I think, where there is nothing as we've defined. What is that temperature reading? I guess it is assumed zero until you run into more particles. nope, there is gas everywhere in the universe even in the deepest coldest regions. This gas is usually hydrogen, they are in voids (1 atom per m2) and more dense areas called intergalactic medium (hundreds of atoms per m2) The more pure know vacuum in the universe in the LHC apparently and also one of the coldest too. To answer the OP, theoretically No, real life Yes. http://en.wikipedia.org/w...er_space#Intergalactic
My computers are liquid cooled while my vehicles are air cooled.
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