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Need a credible reference

  1. Oct 25, 2004 #1
    Hi Guys,

    I'm in an argument with someone on another forum (car forum no less) and he refuses to accept that nuclear reactions break the first law of classical thermodynamics. I'm only trying to show him that before energy and mass were shown to be interchangeable, the laws of conservation energy and of conservation of mass is the classical sense are violated by nuclear/radioactive processes. However, it's so commonly accepted now that mass-energy is conserved together rather than seperately, I can't find a valid and credible source that distinguishes between classical and more modern thermodynamics.

    Can anyone help with a link? Thanks guys.
  2. jcsd
  3. Oct 26, 2004 #2


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    I am not aware of nuclear reactions breaking any laws of thermodynamics.
  4. Oct 26, 2004 #3
    Just that taken seperate from each other, the laws of conservation of mass and conservation of energy don't hold, because we'll lose mass in a nuclear reaction. Not until the revelation that e=mc^2 and the combination of the two laws do we actually get a conservation law that is not broken.

  5. Oct 26, 2004 #4
    You shouldn't see this as a violation of the 1st law of thermodynamics, you should rather consider that in the first law, energy can now (since Einstein) include what is available through E = mc^2 in the case where you have nuclear reactions.
  6. Oct 26, 2004 #5
    Alrighty then... No wonder it was hard to find that reference. Heh.

    And yeah, obviously that's what makes the most sense. But the argument was about the classical definition which I was arguing wuold have to be observed in the strictest sense. But yeah, whatever.
    Last edited: Oct 26, 2004
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