The refrigerant-134a enters the compressor of a refrigeration machine with a pressure of 100 kPa and a flow rate of 0.5 m/min at -20C, and exits at a pressure of 0.8 MPa. The isentropic efficiency of the compressor is 78%. The refrigerant enters the throttling valve at a pressure of 0.75 MPa and a temperature of 26C, and exits the evaporator as saturated steam at a temperature of -26C. Show the cycle in a T-s diagram with saturated liquid and saturated vapor curves. Also, calculate (a) the power required to operate the compressor, (b) the heat absorbed from the cooled medium per unit time, (c) the pressure drop of the refrigerant in the line between the evaporator and the compressor and the amount of heat gain. Solution: (a) 2.40 kW, (b) 6.17 kW, (c) 1.73 kPa, 0.203 kW