what does the 'law of quipartitional energy' says?? what is it all about?
It comes from thermodynamics and kinetic theory. The law of equipartion of energy says that when molecules are in equilibrium the average energy associated with each degree of freedom is 1/2kT (k is Boltzmann's constant).
As an example take a monatomic gas. All it's atoms can do is translate (no rotational or vibrational modes), so the average energy per atom is 3/2kT, since there are three translational degrees of freedom.
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