(a) For the Otto cycle shown in Fig. 20.6, calculate the changes in entropy of the gas in each of the constant-volume processes b → c and d → a in terms of the temperatures Ta Tb Tc and Td and the number of moles n and the heat capacity Cv of the gas.
(b) What is the total entropy change in the engine during one cycle? (Hint:
Use the relationships between Ta and Tb and between Td and Tc.)
(c) The processes b → c and d → a occur irreversibly in a real Otto engine.
Explain how can this be reconciled with your result in part (b).