1. Air is expanded in a nozzle from a stagnation state of 2 MPa, 600 K, to a back pressure of 1.9 MPa. If the exit cross-sectional area is 0.003 m2, find the mass flow rate.
2. A 1-m3 insulated tank contains air at 1 MPa, 560 K. The air in the tank is now discharged through a small convergent nozzle to the atmosphere at 100 kPa. The nozzle has an exit area of 2 × 10-5 m2.
a. Find the initial mass flow rate out of the tank.
b. Find the mass flow rate when half of the mass has been discharged.