In an aircraft jet engine at takeoff, the combustion products expand adiabatic ally in the exhaust nozzle. At entrance to the nozzle, the pressure is 0.180 MPa and the temperature is 1200 K. The kinetic energy of the gas entering the nozzle is very mu Ch smaller than the kinetic energy of the gas leaving the nozzle. The specific heat of the exhaust gas vanes with temperature approximately as follows:

    Cp = 0.959 + 1.16(10^-4)T + 3.65(10^-8)T kj/kg*k

in which the units of cp are kJ/(kg - K) and T is the temperature in K. The molecular weight of the exhaust gas is 30. Supposing the expansion to be friction less (reversible) as well as adiabatic, show how the exhaust velocity and pressure will depend on the exhaust temperature for a series of values: 1100,1000, and 900 K. At each temperature determine also the speed of sound √γRT.