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Homework Help: Need help with stat thermo qtn

  1. Feb 5, 2009 #1
    1. The problem statement, all variables and given/known data

    Classical Ideal Gas in 3 Dimensions
    In a classical ideal gas, we treat molecules as non-interacting point particles moving in the x,y, and z directions. These particles' velocities (in each respective direction) are statistically independent:

    p(Vx,Vy,Vz)=C*exp-(Vx^2+Vy^2+Vz^2)

    The energy is E=1/2*m*|v|^2

    (a) Find P(E), the overall probability that these gas particles will have a KE \<E.
    (b) By noting that dP=p(E)dE, derive the probability density p(E).

    2. Relevant equations
    No clue

    3. The attempt at a solution
    Don't even know how to start...any tips would be much appreciated
     
  2. jcsd
  3. Feb 5, 2009 #2

    Ygggdrasil

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    Can you re-write the expression for p(Vx,Vy,Vz) so that the probability depends on E rather than Vx, Vy, and Vz?
     
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