An ideal gas undergoing a polytropic process approaches a process under this constraint as the polytropic index goes to infinity. The heating and cooling in the Stirling cycle is performed under this condition. For a constant number of particles and under this constraint, (15[1])the reciprocal (15[1])of the partial derivative of the entropy with respect to energy defines the absolute temperature. The (*) Helmholtz free energy is defined as the amount of usable work under this constraint. (10[1])No work is performed under this constraint, so the specific heat under this condition is always smaller than the specific heat at constant pressure. For 10 points, (10[1])isochoric processes occur under what thermodynamic constraint, in which the size (-5[1])of the container does not change? ■END■ (10[1])