CALC An object of mass m1, specific heat c1, and temperature T1 is placed in contact with a second object of mass m2 specific heat c2, and temperature T2 > T1. As a result, the temperature of the first object increases to T and the temperature of the second object decreases to T′. (a) Show that the entropy increase of the system is
and show that energy conservation requires that
(b) Show that the entropy change ΔS. considered as a function of T, is a maximum if T = T′, which is just the condition of
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