(III) A real heat engine working between heat reservoirs at970 K and 650 K produces 550 J of work per cycle for a heatinput of 2500 J. (a) Compare the efficiency of this real engineto that of an ideal (Carnot) engine. (b) Calculate the totalentropy change of the universe per cycle of the real engine,and (c) also if the engine is ideal (Carnot).

(b) (1) Explain how a change in system energy and heat are related in thermodynamics with respect to surroundings. (ii) A manufacturer claims to have constructed an engine that has an efficiency of 35%, when operated between the Boiling point of water and the freezing point of water. Is his claim correct? Justify your answer with calculations.

(i)     Define the term entropy in thermodynamics. (ii)    In what way entropy is related to third law of thermodynamics? Compare and contrast adiabatic processes and Cyclical processes in thermodynamics with necessary explanations and sketches. Let 1.00 kg of liquid water at 100°C be converted to steam at a pressure of 1.01 * 105 Pa. The volume of water changes from an initial value of 1.00 * 10-3 m3 as a liquid to 1.671 m3 as steam. The heat of vaporization is 2256 kJ/kg. (i)               How much work is done by the system during the process? (ii)              How much energy is transferred as heat? (iii)            What is the change in the system’s energy during the process?