Air passes from a large reservoir at 70F through an isentropic converging-diverging nozzle into the atmosphere. The nozzle throat area is 1 cm2 , and that of the exit is 2 cm2 .

a) Determine the reservoir pressure at which the flow in the nozzle just reaches sonic velocity.

b) Calculate the mass flow rate and exit Mach number under the conditions given in part (a).