At steady state, a power cycle develops a net power output of 20kW while receiving energy by heat transfer at a rate of 20kJ per cycle of operation from a source at a temperature T. The cycle rejects energy by
heat transfer to cooling water at a lower temperature of 525 K. If there are 175 (engine thermodynamic)
cycles per minute, what is the minimum theoretical value for T, in K?

Air inially occupying a volume of 1 m2 at 100 kpa, 27 c undergoes three internally reversible processes in series. process 1-2 compression to 500 kpa during which pv constant process 2-3 adiabatic expanslon to 100 kpa process 3-1: constant-pressure expansion to 100 kpa (a) calculate the change of entropy for each of the three processes. (b) calculate the heat and work involved in each process. (c) is this cycle a power cycle or refrigeration cycle?