Air enters a converging–diverging nozzle with low velocity at 2.0 MPa and $100^{\circ} \mathrm{C}$. If the exit area of the nozzle is 3.5 times the throat area, what must the back pressure be to produce a normal shock at the exit plane of the nozzle?

Air enters a nozzle at 0.5 MPa, 420 K, and a velocity of 110 m/s. Approximating the flow as isentropic, determine the pressure and temperature of air at a location where the air velocity equals the speed of sound. What is the ratio of the area at this location to the entrance area?

The energy flux associated with solar radiation incident on the outer surface of the earth’s atmosphere has been accurately measured and is known to be $1368 \mathrm{W} / \mathrm{m}^{2}$. The diameters of the sun and earth are $1.39 \times 10^{9}$ and $1.27 \times 10^{7} \mathrm{m}$, respectively, and the distance between the sun and the earth is $1.5 \times 10^{11} \mathrm{m}$. (a) What is the emissive power of the sun? (b) Approximating the sun’s surface as black, what is its temperature? (c) At what wavelength is the spectral emissive power of the sun a maximum? (d) Assuming the earth’s surface to be black and the sun to be the only source of energy for the earth, estimate the earth’s surface temperature.

Air enters a nozzle steadily at 50 psia, $140^\circ F,$ and 150 ft/s and leaves at 14.7 psia and 900 ft/s. The heat loss from the nozzle is estimated to be 6.5 Btu/lbm of air flowing. The inlet area of the nozzle is $0.1 ft^2.$ Determine (a) the exit temperature of air and (b) the exit area of the nozzle.

A sound wave is observed to travel through a liquid with a speed of 1500 $\mathrm{m} / \mathrm{s}$ . The specific gravity of the liquid is 1.5. Determine the bulk modulus for this fluid.

For an ideal gas flowing through a normal shock, develop a relation for $V_2/V_1$ in terms of k, $M_{a1}$, and $M_{a2}$.