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Homework Help: Thermodynamics problem#2

  1. Jun 9, 2007 #1
    1. The problem statement, all variables and given/known data

    Show that if the Kelvin Planck statement of the 2nd law were not true,a violation of the Clausius statement would be possible.

    2. Relevant equations
    3. The attempt at a solution Please check if I am correct.

    Kelvin Planck statement says that it is impossible for any system to operate in thermodynamic cycle and deliver a net amount of work to its surroudnings while receiving energy by heat transfer from a single thermal reservoir.
    Qcool>0 and efficiency <1
    Kelvin Planck statement is not true because you can't the net amount of work to its surroundings while receiving energy by heat transfer from a single thermal reservoir.

    we know the second law of thermodyanics cycle is that you have hot reservior and cool reservoir. and you can have work output from the hot reservoir by extract heat from and reject heat to cool reservoir
  2. jcsd
  3. Jun 10, 2007 #2


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    Prove it by contradiction. ie, construct a hypothetical thermodynamic device in which it's possible to deliver work while recieving heat from a single reservoir. What can you do with this work which violates the Clausius statement?
    Last edited: Jun 10, 2007
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