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Kinetic theory

  1. Nov 29, 2009 #1
    Does the rms speed of a gas change when the no of molecules are lowered, isothermally?
    I know that at same temp, avg kinetic energy remains the same.
    m1 (v1)2 = m2 (v2)2

    If m2 = m1/2, v22 = 2 v12
    Is this correct?
  2. jcsd
  3. Nov 29, 2009 #2


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    The number of molecules is N as in pV = NkT. The symbol m stands for the mass of a molecule, not the number of molecules.
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