Air enters the rotor of an axial compressible stage with an axial velocity of 150 m/s and a tangential component of 80 m/s. The average rotor blade speed is 250 m/s. The blade angles are 48 degrees at the rotor inlet and 28 degrees at the rotor outlet (25 pts) a) Assuming the axial velocity component remains unchanged through the rotor passage, what is the change in tangential velocity ( C ) through the rotor passage

The proportional limit is always greater than the yield strength for a material. a)-trune b)- false

Aheat pump with refrigerant-134a as the working fluid is used to keep a space at 25°c by absorbing heat from geothermal water that enters the evaporator at 500c at a rate of 0.065 kg/s and leaves at 40°c. the refrigerant enters the evaporator at 20°c with a quality of 23 percent and leaves at the inlet pressure as saturated vapor. the refrigerant loses 300 w of heat to the surroundings as it flows through the compressor and the refrigerant leaves the compressor at 1.4 mpa at the same entropy as the inlet. determine: (a) the degrees of subcooling of the refrigerant in the condenser, b)-the mass flow rate of the refrigerant . (c) the heating load and the cop of the pump, and d)-the theoretical minimum power input to the compressor for the same heating load.

Air undergoes a constant pressure cooling process with no moisture added or removed. the air originally exists at 45 °c, 150 kpa and 35 % relative humidity. it is cooled until the temperature reaches 29 oc. determine (a) the relative humidity of the cooled air. (b) the dew point temperature of the cooled air in °c. (c) the heat removed during the cooling process in kj/kg. use the psychrometric chart to check your answers (this part will not be graded; however, it will you get comfortable using the psychrometric chart)