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Homework Help: Density of states of ideal gas and photon gas

  1. Nov 6, 2011 #1
    1. The problem statement, all variables and given/known data

    I know how to derive the density of states for an ideal gas by using the energy equation:

    E_n = A*n^2, where A = (h_bar^2*pi^2)/(2mL^2)

    but what about for a 'photon gas'? Do I use the same energy equation as above, or the following:

    E_n = (h_bar*pi*c/L)*n

    2. Relevant equations

    3. The attempt at a solution

    I think I'd use the second equation, but solutions to the assignment said use the first equation. I'm confused!
  2. jcsd
  3. Nov 6, 2011 #2

    Simon Bridge

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    Regular gas in a box derivation.
    Note: photons are Bosons and massless with two spin states.
    Last edited: Nov 6, 2011
  4. Nov 6, 2011 #3
    Thanks, this helped a lot :)
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