Question: Air flows through a convergent-divergent nozzle. The stagnation temperature of supply air is 200°C and the nozzle has an exit area of 2 m2 and a throat area of 1 m2. If the air from the nozzle is discharged to an ambient pressure of 70 kPa, find the minimum supply stagnation pressure required to produce choking in the nozzle and the mass flow rate through the nozzle when it is choked. Also, find the supply stagnation pressure that exists if a normal shock wave occurs in the divergent portion of the nozzle at a section where the area is 1.5 m2.