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Homework Help: Thermodynamics Problem Clarification

  1. Jun 11, 2007 #1
    1. The problem statement, all variables and given/known data

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

    2. Relevant equations



    3. The attempt at a solution

    My attempts: Please check it and confirm if I am correct.

    Clausius Statement - States that it is impossible to construct a device that operates in a cycle and produces no effect other than the transfer of heat from a lower temperature body to a higher temperature body.

    Kelvin-Planck Statement - States that no system can produce a net amount of work while operating in a cycle and exchanging heat with a single thermal energy reservoir.

    let there be a heat pump HP which takes Q2 heat from TL and delivers it to TH(Clausius statement)
    Let us consider another Heat engine that takes heat a source TH and delivers a wet work out put W_net and rejects Q2 heat to sink.

    Now we can remove T(LOW), and feed the Q2 heat from HE to HP

    Now considering HE+HP as a single heat engine, we see it produces a net work Wnet while exchanging heat with a single energy reservior(KelvinP statement)
     
  2. jcsd
  3. Jun 11, 2007 #2

    berkeman

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    Staff: Mentor

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