A piston–cylinder device initially contains 0.8 m3 of nitrogen gas at 534 kPa and 22 °C. An electric heater within the device is turned on and is allowed to pass a current of 2 A for 8 min from a 107 -V source. Nitrogen expands at constant pressure, and a heat loss of 1,876 J occurs during the process. Determine the final temperature of nitrogen. Assume that Cp for nitrogen is equal to 1.039 KJ

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?