There are two masses of finite size in contact with a constant thermal reservoir. Initially, the masses are separated, with one at a higher, or hotter, temperature (Th) than the other (it is colder, at Te). The hotter mass has a heat capacity C, and the colder mass a heat capacity C. Both masses are in an adiabatic chamber. The masses are slowly brought into contact and thermal equilibrium is reached. Calculate the change in entropy of the system, and show that when Ch = Ce = C, that change is described by the expression: Th + Te 2C In Is this entropy change physically reasonable?

There are two masses of finite size in contact with a constant thermal reservoir. Initially, the masses are separated, with one at a higher, or hotter, temperature (Th) than the other (it is colder, at Te). The hotter mass has a heat capacity C, and the colder mass a heat capacity C. Both masses are in an adiabatic chamber. The masses are slowly brought into contact and thermal equilibrium is reached. Calculate the change in entropy of the system, and show that when Ch = Ce = C, that change is described by the expression: Th + Te 2C In Is this entropy change physically reasonable?