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Homework Help: Thermodynamics Problem

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

    A closed system contains 3 kg of R-134a at 10 °C and 90 kPa (state 1), and undergoes an internally reversible, isothermal process until the volume of the R-134a reaches 0.056 m3 (state 2). The system returns to state 1 by an irreversible process and the heat transfer for the return process is +3.2 kJ. Determine Q12, W12, W21 and the entropy change for each process.


    2. Relevant equations



    3. The attempt at a solution

    I do not know how to go about doing this. Any help will be appreciated. thanks.
     
  2. jcsd
  3. Mar 1, 2007 #2
    Start out by drawing an T-s, P-V, and T-V diagram, to better see the cycle
     
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