Consider a pipe of 5-cm diameter and 5 m long carrying a discharge of 0.005 m3/s. now the central 2 m length is replaced by a 7.5 cm diameter pipe and the changes being sudden. determine the head loss and the corresponding power assuming that the friction factor of 0.01 for both diameters and a contraction loss coefficient of 0.5

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.