If the partition function of a harmonic oscillator with frequency $$\omega $$ at a temperature T is $$\frac{{kT}}{{\hbar \omega }},$$ then the free energy of N such independent oscillators is
The free energy for a photon gas is given by $$F = - \left( {\frac{a}{3}} \right)V{T^{ - 4}},$$ where a is a constant. The entropy S and the pressure p of the photon gas are
Consider black body radiation in a cavity maintained at 2000 K. If the volume of the cavity is reversibly and adiabatically increased from 10 cm3 to 640 cm3, the temperature of the cavity changes to
Consider a system of N atoms of an ideal gas of type A at temperature T and volume V. It is kept in diffusive contact with another system of N atoms of another ideal gas of type B at the same temperature T and volume V. Once the combined system reaches equilibrium,
The internal energy of n moles of a gas is given $$E = \frac{3}{2}nRT - \frac{a}{V},$$ where V is the volume of the gas at temperature T and a is a positive constant. One mole of the gas in state (T1, V1) is allowed to expand adiabatically into vacuum to a final state (T2, V2). The temperature T2 is
Consider a system of two non-interacting classical particles which can occupy any of the three energy levels with energy values E = 0, ε and 2ε having degeneracies g(E) = 1, 2 and 4 respectively, The mean energy of the system is