Refrigerant 134a enters the condenser of a residential heat pump at 800 kPa and 55 oC at a rate of 0.018 kg/s and leaves at 750 kPa and saturated liquid condition. The refrigerant enters the compressor at 200 kPa superheated by 5 oC. Determine a) the isentropic efficiency of the compressor, b) the rate of heat supplied to the room and c) the COP of the heat pump.

Acompressor receives the shaft work to decrease the pressure of the fluid. a)- true b)- false

Water in a partially filled large tank is to be supplied to the roof top, which is 8 m above the water level in the tank, through a 2.2-cm-internal-diameter pipe by maintaining a constant air pressure of 300 kpa (gage) in the tank. if the head loss in the piping is 2 m of water, determine the discharge rate of the supply of water to the roof top in liters per second.

Acircular aluminum shaft mounted in a journal is shown. the symmetric clearance gap between the shaft and journal is filled with sae 10w-30 oil at t 30°c. the shaft is caused to turn by the attached mass and cord. develop and solve a differential equation for the angular speed of the shaft as a function of time.