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## Re: [Tigers] Laws of Thermodynamics

 To: tigers@autox.team.net Re: [Tigers] Laws of Thermodynamics Tod Brown Sun, 20 Apr 2008 09:27:34 -0400
 ```Steve's original statement of the Laws of Thermodynamics as given by C.P. Snow are pretty succinct and an easy way to remember them. When stated in the usual language of physics, they do become a little less clear to the layman. Whichever way you prefer, I would add a couple of things as an attempt at clarification and elaboration. The First Law is also known as the Law of Conservation of Energy. Most people have heard of this, but it simply states that the total amount of energy in an isolated system is constant. That is, energy can be converted from one form to another, but cannot be created or destroyed. Automobile engines operated by converting the chemical energy stored in gasoline into heat. Engine modifications to gain power are involved with finding ways to convert the energy content in gasoline into heat more rapidly. Power is the measure of how fast energy is being converted. You can, of course, use gasoline with more energy content (i.e. higher octane) as well, but the principle remains - energy in = energy out. The Second Law, also known as the Law of Entropy, concerns itself with more practical matters. It basically says that energy conversions involve "losses". Most of the time these losses appear as heat, which is just the random motion of molecules. In an automobile engine, when the chemical energy stored in the gasoline is converted into motion of the engine, some of the energy is also converted to heat due to friction. This turns out to be quite a bit of energy, so most automobile engines are not very efficient devices. The Second Law also explains why many processes, even though they do not violate the First Law, are not seen to take place. That is why many processes that can be observed in a film run backwards seem so strange - they represent processes which diminish the amount of Entropy (or disorder) in a system. Put simply, things run downhill spontaneously, not uphill. It is on the basis of this law that perpetual motion devices are precluded. One can get into a lot of philosophical discussions with the Law of Entropy and the implications it has for the direction of time, etc. One other interesting aspect of this law is that it is not absolutely true, in the sense that it is a statement of statistical probabilities. Finally, these laws operate whether we wish them to or not. Consequently, it would, indeed, be helpful if those who determine the policies of our government with regard to energy could take the time to understand them. The comments of a couple of folks in this forum regarding the conversion of corn into ethanol and the possibility of using hydrogen power for vehicles might be better understood in light of these laws. Tod B382002384LRXFE (constantly generating entropy in my little corner of the universe) _______________________________________________ Support Team.Net http://www.team.net/donate.html Tigers@autox.team.net http://autox.team.net/mailman/listinfo/tigers http://www.team.net/archive ```
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