An electron spin can adopt either of two orientations ...

An electron spin can adopt either of two orientations in a magnetic field, and its energies are ±μB, where μis the Bohr magneton. Deduce an expression for the partition function and mean energy of the election and sketch the variation of the functions with B. Calculate the relative populations of the spin states at (a)4.0K (b)298K when B=1.0T
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