Air enters the compressor of a brayton refrigeration cycle at 100 kpa, 270 k. the compressor pressure ratio is 3, and the temperature at the turbine inlet is 315 k. the compressor and turbine have isentropic efficiencies of 75% and 90%, respectively. determine the network input per unit mass of air in kj/kg. the tolerance is ±5%.

Aplate clutch has a single pair of mating friction surfaces 250-mm od by 175-mm id. the mean value of the coefficient of friction is 0.30, and the actuating force is 4 kn. a) find the maximum pressure and the torque capacity using the uniform-wear model. b) find the maximum pressure and the torque capacity using the uniform-pressure model.