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Perpetual Motion Machine?

  1. Jul 31, 2007 #1
    I've heard a perpetual motion machine would be impossible, but then that some people out there believe it is. I was wondering if anyone out there has any thoughts on it..
  2. jcsd
  3. Jul 31, 2007 #2
    Its papers done by high school flunkiees.
  4. Jul 31, 2007 #3

    Claude Bile

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    It is impossible. You can take that as holy writ.

  5. Jul 31, 2007 #4


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    By the usual definition of 'perpetual motion', no one with an ounce of brains believes in them. It is possible to have something that moves forever once started, such as a rock spinning in outer space or electric current in a superconducting loop. The point is that no work can be extracted from it without killing it.
  6. Jul 31, 2007 #5


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    PMM thread: alive 55 minutes and counting!
  7. Jul 31, 2007 #6


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    In this forum we obey the laws of thermodynamics!
  8. Jul 31, 2007 #7


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  9. Jul 31, 2007 #8


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  10. Jul 31, 2007 #9


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    The key here is the term "perpetual motion machine"; the word "machine" makes it a device that helps one do work. As Danger mentioned, there are events that can give the appearence of perpetual motion, but they can't be called machines, 'cause we can't get any work out of 'em.
    I don't know if you wanted details as to why such a device can't exist, or if you're just taking a little opinion pol.
  11. Jul 31, 2007 #10


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    Sorry. We were busy.... thread locked.
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