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Homework Help: Internal energy and pv diagrams!

  1. Aug 18, 2010 #1
    [PLAIN]http://img689.imageshack.us/img689/511/pistonquerstion.jpg [Broken]

    This is my part attempt...

    [PLAIN]http://img830.imageshack.us/img830/7342/internalenergyanswer.jpg [Broken]

    And ideas on how I can do the rest of it?
     
    Last edited by a moderator: May 4, 2017
  2. jcsd
  3. Aug 18, 2010 #2
    Actuall I think I have managed to work outish a). I used the first law of thermodynamics: E = Q + W

    then giving that in the question it says: Q(isobarbic)= 200j

    So since W = -PdV = -P(Vf-Vi)

    I for internal energy of the syster at this point: U = 185j

    Am I doing it right?
     
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