gas dynamic Example (4-3): An airstream flow in a converging duct from a cross-sectional area A1 of 50 cm2 to a cross-sectional area A2 of 40 cm2. If T1 = 300 K, P1 = 100 kPa, and V1 = 100 m/s. Find M2, P2, and T2. Assume steady, one-dimensional isentropic flow.