Air with a mass flow rate of 2.3 kg/s enters a horizontal nozzle operating at steady state at 450K, 350kPa, and a velocity of 3 m/s. At the exit, the temperature is 300K and the velocity is 460 m/s. Using the ideal gas model for air with constant cp =1.011 kJ/kg.K,
determine (a) the area at the inlet, in m2, and (b) the heat transfer between the nozzle and its surroundings, in kW. Specify whether the heat transfer is to or from the air.