A C-D nozzle is supplied from an air reservoir at 1000 kPa. It has an area ratio of (Aexit/Athroat) 4. Calculate: a. The range of back pressures over which there is subsonic flow in the diverging section of the nozzle (10 points) b. The range of back pressures when the flow is at the designed supersonic Mach number at exit of the nozzle (10 points)

Consider a large isothermal enclosure that is maintained at a uniform temperature of 2000 k. calculate the emissive power of the radiation that emerges from a small aperture on the enclosure surface. what is the wavelength ? , below which 10% of the emission is concentrated? what is the wavelength ? 2 above which 10% of the emission is concentrated? determine the wavelength at which maximum spectral emissive power occurs. what is the irradiation incident on a small object placed inside the enclosure?