Chapter 6, Problem 6.75P

A reversible heat engine absorbs 3000 kJ from a reservoir at 1000 K and rejects 2500 kJ at 500 K. Find the heat interchanged with the reservoir at 300 K and the net work output of the engine.

Problem 4.01. A carnot refrigerator (carnot cycle heat pump in reverse) operating between Th and Te is used to cool and freeze a bottle of water, volume V, at a temperature To < Th to freezing temperature T (known density Pw, heat capacity cw). (a) Find the work required to cool and freeze the water. (b) Find the change in entropy in the heat baths, and use it to place a limit on the change in entropy of the water (without calculating the entropy change in the water). The C.O.P. of a carnot refrigerator: KR= Qc = W Te Th-Te

A piston with water vapor at a pressure of 300 kPa and a temperature of 175 oC. 20 kg of fluid is compressed up to 950 kPa pressure in the cylinder arrangement. Piston cylinder device to a heat well at 80 oC in order to keep the temperature of the water in it constant. The heat generated during compression is discarded. a) What phase is the water in the first case? In the last case, what phase is the water in? b) Find the entropy change in water by the process. c) From the cylinder, assuming that the process is a reversible process at constant temperature. Calculate the amount of heat absorbed. d) Find the entropy change of the heat well. e) Consider the total entropy change including the piston-cylinder mechanism and the heat indicate whether the transaction is reversible or irreversible when received. f) T (° C) -s (kJ / kgK) and P (Pa) - by specifying the state change saturation curves and values Show in (m³ / kg) diagrams.