(a) Show that, for any magnetizable material, the heat capacities at constant field H and at constant magnetization M are connected by the relation
CH−CM=−T(∂T∂H)M(∂T∂M)H.
(b) Show that for a paramagnetic material obeying Curie's law
CH−CM=CH2/T2,
where C on the right-hand side of this equation denotes the Curie constant of the given sample.