A gas for which = 5 / 3 ( = C_p / C_v ) is heated at constant pressure. The percentage of heat supplied used for external work is

Step-by-step solution

Heat supplied at constant pressure is given by Q = n C_p T Work done by the gas is given by W = P V = n R T The fraction of heat used for external work is W Q = n R T n C_p T = R C_p Using Mayer's relation C_p - C_v = R and = C_p C_v , we have C_p - C_p = R R C_p = 1 - 1 = - 1 Given = 5 3 , substituting this value: W Q = 5 3 - 1 5 3 = 2 5 Percentage of heat used for external work is 2 5 100 % = 40 % Answer: 40 %