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Thermodynamics Question

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

    Determine the work required per pound mass to isothermally and frictionlessly compress R-134a in a closed system from a saturated vapor to a saturated liquid at 20 °F.

    2. Relevant equations

    3. The attempt at a solution

    I do not know where to begin with this problem. Any help would be appreciated. thanks.
  2. jcsd
  3. Feb 2, 2007 #2
    Start with the first law of thermodynamics. Probably a few assumptions in the problem, like KE and PE = ?
    Also you'll need the charts, probably in the back of your text.
  4. Feb 2, 2007 #3


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    Science Advisor

    Just to add:

    Write down the first law.

    Isentropic.....No Entropy production
    You can also assume no potential or kinetic changes.

    What is left?
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