Quostion 4 Air enters a pipe of lin diameter at subsonic velocity and P1=30 psia, T1=550R. If the pipe is 10f long, f=0.025 and the exit pressure P2=20 psia. air=1.4 a. Define Mach number and significance in terms of distinguishing between incompressible and compressible fluids. Explain your assumptions and the equation(s) to be used. (6 marks) b. Calculate the mass flow for isothermal flow. (6 marks) c. Calculate the Mach number at the Inlet and Outlet (6 marks) d. Determine maximum length of the pipe before choking occurs (7 marks) Question 5 Gas flowing through a converging-diverging nozzle experiences a normal shock, as per graphic A. a. What is the physical meaning/application of this problem in the industry. Explain your assumptions and the equation(s) to be used ( 8 marks) b. Calculate Mach number Ma2 ( 8 marks) c. Calculate Air velocity u2 ( 9 marks) Assume that: 1. Air is an ideal gas with constant specific heat. II. Flow through the nozzle is steady, one-dimensional, and isentropic before the shock occurs. III. The shock wave occurs at the exit plane. Data: a. air=1,4 b. Rair=0.06855Btu/bmR, c. Pa=1MPa d. Ta=300K e. Ma1=2.4 Graphic A. Air flowing through converging-diverging nozzle