If the frequency of a normal mode is $\omega_{mode}=10^{12}rads^{-1}$, what phonon number, $n_{phonon}$, does the equipartition theorem predict at room temperature?
This SWBQ demonstrates to students how the energy stored in a normal mode is directly proportional to the frequency of the normal mode and how the equipartition theorem is useful for finding the phonon number of a normal mode as long as not on the scale $n_{phonon}\, \sim \, 1$. In particular, students must recall that the energy stored in a single normal mode is $k_{B}T$.