An adiabatic air compressor compresses $10 \mathrm{~L} / \mathrm{s}$ of air at $120 \mathrm{kPa}$ and $20^{\circ} \mathrm{C}$ to $1000 \mathrm{kPa}$ and $300^{\circ} \mathrm{C}$. Find $(a)$ the work needed by the compressor, in $\mathrm{kJ} / \mathrm{kg}$, and (b) the power needed to drive the air compressor, in $k W$.

An airplane has a rectangular-planform wing that has an elliptical spanwise lift distribution. The airplane has a mass of 1000 kg, a wing area of 16 m2, and a wingspan of 10 m, and it is flying at 50 m/s at 3000 m altitude in a standard atmosphere. If the form drag coefficient is 0.01, calculate the total drag on the wing and the power (P=FDV) necessary to overcome the drag.

A heat engine cycle is executed with steam in the saturation dome. The pressure of steam is 1 MPa during heat addition, and 0.4 MPa during heat rejection. The highest possible efficiency of this heat engine is (a) 8.0% (b) 15.6% (c) 20.2% (d) 79.8% (e) 100%

An airplane has a mass of 48,000 kg, a wing area of 300 $m^2$, a maximum lift coefficient of 3.2 , and a cruising drag coefficient of 0.03 at an altitude of 12,000m. Determine

(a) the takeoff speed at sea level, assuming it is 20 percent over the stall speed, and

(b) the thrust that the engines must deliver for a cruising speed of 900 km/h.

An air compressor compresses $10 \mathrm{~L}$ of air at $120 \mathrm{~kPa}$ and $20^{\circ} \mathrm{C}$ to $1000 \mathrm{~kPa}$ and $300^{\circ} \mathrm{C}$. Determine the flow work, in $\mathrm{kJ} / \mathrm{kg}$, required by the compressor.

An adiabatic air compressor compresses 10 L/s of air at 120 kPa and 20$^{\circ}$C to 1000 kPa and 300$^{\circ}$C. Determine the power required to drive the air compressor, in kW.

A windows air conditioner that consumes of 1 kW of electricity when running and has a coefficient of performance of 3 is placed in the middle of a room and is plugged in. The rate of cooling or heating this air conditioner will provide to the air in the room when running is (a) 3 kJ/s, cooling (b) 1 kJ/s, cooling (c) 0.33 kJ/s, heating (d) 1 kJ/s, heating (e) 3 kJ/s, heating

A 0.2- m$^3$ rigid tank equipped with a pressure regulator contains steam at 2 MPa and 300 degree C. The steam in the tank is now heated. The regulator keeps the steam pressure constant by letting out some steam, but the temperature inside rises. Determine the amount of heat transferred when the steam temperature reaches 500 degree C.

Steam flows steadily through a turbine at a rate of 45,000 lbm/h, entering at 1000 psia and $900^\circ F$ and leaving at 5 psia as saturated vapor. If the power generated by the turbine is 4 MW, determine the rate of heat loss from the steam.

A 0.2-m^3 rigid tank equipped with a pressure regulator contains steam at 2 MPa and 300$^\circ{}$C. The steam in the tank is now heated. The regulator keeps the steam pressure constant by letting out some steam, but the temperature inside rises. Determine the amount of heat transferred when the steam temperature reaches 500$^\circ{}$C.

Helium in a piston/cylinder at 70 F, 20 psia is brought to 720 R in a reversible polytropic process with exponent n = 1.25. You may assume that helium is an ideal gas with constant specific heat. Find the final pressure and both the specific heat transfer and the specific work.

An air compressor compresses 6 L of air at 120 kPa and 20$^\circ{}$C to 1000 kPa and 400$^\circ{}$C. Determine the flow work, in kJ/kg, required by the compressor. Answer: 109 kJ/kg

The gas-turbine cycle shown in figure is used as an automotive engine. In the first turbine, the gas expands to pressure $P_5$, just low enough for this turbine to drive the compressor. The gas is then expanded through the second turbine connected to the drive wheels. The data for the engine are shown in the figure, and assume that all processes are ideal. Determine the intermediate pressure $P_5$, the net specific work output of the engine, and the mass flow rate through the engine. Find also the air temperature entering the burner $T_3$ and the thermal efficiency of the engine.

A frictionless piston-cylinder device contains 5 kg of nitrogen at 100 kPa and 250 K. Nitrogen is now compressed slowly according to the relation $P V^{1.4}=$ constant until it reaches a final temperature of 450 K. Calculate the work input during this process.