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Homework Help: Help with the Carnot Cycle

  1. Dec 1, 2011 #1
    1. The problem statement, all variables and given/known data
    its part VI) of a big problem, where:

    0.12 moles of argon (40) undergoes the cycle abca described in the graph. Process ab lies on a 540k isotherm.

    In the previious 5 sub problems, i figured that:

    Tc=270k
    Qbc=670J (lost)
    Qca=400J (added)
    Wab=370J
    Wabca=100J


    The PV diagram has points a,b and c where:

    a=(1.5X10-3, 3.6X105)
    b=(3X10-3, 1.8X105)
    c=(1.5X10-3, 1.8X105)







    2. Relevant equations

    Q=mc[itex]\Delta[/itex]T

    [itex]\Delta[/itex]U=Q+W

    [itex]\epsilon[/itex]=1-Qout/Qin=1-Tlow/Thigh

    3. The attempt at a solution
    So it's basically using Qabca to find the efficiecy. The thing is that im not sure what to use for the Qs.
     
  2. jcsd
  3. Dec 1, 2011 #2
    What is Qs supposed to represent? I don't see it in your problem statement.
     
  4. Dec 1, 2011 #3
    it's a plural for Q, I am not sure what to use for Qin and Qout
     
  5. Dec 2, 2011 #4
    Remember this is NOT a carnot cycle. η= 1- Qout/Qin There is also a Qin between A and B. Do you know what it is? It is the Qout/ the Total Qin.
     
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