Post
by Imperate » Mon Sep 29, 2008 12:30 pm
Hey, I thought exactly the same thing when I first did this question. Whilst I accept B is true, I find it hard to negate choice A. Since by equipartition, each degree of freedom has 1/2kT, and each atom has 3 kinetic degrees of freedom, 3 potential degrees of freedom, suggesting its average energy is 6*1/2kT=3kT.
Maybe it has something to do with the fact equipartition only applies at high temperatures, and is not a general feature of the Einstein or Debye model, rather just a limit.