1. Not finding help here? Sign up for a free 30min tutor trial with Chegg Tutors
    Dismiss Notice
Dismiss Notice
Join Physics Forums Today!
The friendliest, high quality science and math community on the planet! Everyone who loves science is here!

Internal energy of a hydrostatic system in a reversible adiabatic process

  1. Feb 11, 2010 #1
    1. The problem statement, all variables and given/known data
    A simple hydrostatic system is such that [tex]PV^k[/tex] is constant in a reversible adiabatic process, where k > 0 is a given constant. Show that its internal energy has the form
    [tex]E=\frac{1}{k-1}PV+NF(\frac{PV^k}{N^k}[/tex]
    where f is an arbitrary function. Hint: [tex]PV^k[/tex] must be a function of S (why?) so that [tex](\partial{E}{S})_S = g(S)V^-k[/tex] where g(S) is an arbitrary function.


    2. Relevant equations



    3. The attempt at a solution
    I used dE + dW = dQ = 0. so dW = PdV. Then we want to find [tex]W=\int PdV[/tex] using the limits V1 and V2 and substituting [tex]P=\frac{P_1}{V_1*V}[/tex]. This works ok to get the first term of the energy out, but not the second. we end up with a term that looks like this as the second term [tex]\frac{P_1*V^k_1}{(1-k)*V^(k-1)_2}[/tex] which doesn't look much like [tex]N\frac{PV^k}{N^k}[/tex]
     
  2. jcsd
Know someone interested in this topic? Share this thread via Reddit, Google+, Twitter, or Facebook

Can you offer guidance or do you also need help?



Similar Discussions: Internal energy of a hydrostatic system in a reversible adiabatic process
Loading...