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Internal energy equals to average kinectic energy ?

  1. Dec 27, 2012 #1
    For ideal gas , can I assume Cv dT = nkT (3/2)
    , thank you
  2. jcsd
  3. Dec 28, 2012 #2

    Andrew Mason

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    No. Molar heat capacity, Cv = 3R/2 only for ideal monatomic gases. You are also mixing temperature change with temperature here.

    Using molar heat capacity 3R/2 for a monatomic ideal gas:

    [itex]\int_{Ti}^{Tf} nC_vdT = \frac{3}{2}nR(T_f - T_i) = \frac{3}{2}nR\Delta T = \frac{3}{2}Nk\Delta T[/itex]

  4. Dec 29, 2012 #3
    Thanks for compact explanation.
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