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Homework Help: Constant Volume Specific Heat

  1. Jun 29, 2005 #1
    Just trying to locate specific heat constants with constant volume (not pressure), any ideas where to find this?
  2. jcsd
  3. Jun 30, 2005 #2
    If you have a thermodynamic set of property tables it would be in the column with Cv (v should be a subscript) if you are looking at Cp that is the specific heat at constant pressure. They should be fairly close in most non-extreme conditions so becareful what your looking at
  4. Jun 30, 2005 #3
    [itex]C_p[/itex] : Specific Heat at constant pressure
    [itex]C_v[/itex] : Specific Heat at constant volume

    Also [itex]C_p - C_v = R[/itex]

    [itex]\frac {C_p}{C_v} = lamda[/itex]

    where lamda = [itex]1 + \frac {2}{f}[/itex]

    Where f=degrees of freedon

    for monoatomic gas , f=3
    for diatomic gas , f=3

    You can solve for two expressions at the top to get Cp

  5. Jul 1, 2005 #4
    One correction to Dr.Brain's post. f for diatomic gases is 5
  6. Jul 1, 2005 #5


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    And that's only at around room temperature's where the vibrational degree of freedom is absent. At high temperatures, f will be 7 for diatomic gases.
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