Consider a heat exchanger that is insulated from its surroundings. assuming the inlet and outlet temperatures of the cold fluid, the inlet temperature of the hot fluid, the mass flow rates, and thermal properties are available, without knowing the heat exchanger type and geometrical characteristics (areas, tube length, & , etc), is it possible to calculate the total heat transfer rate, q? a. no. b. yes, but cr must be 0. c. yes.

Acommercial refrigerator with refrigerant-134a as the working fluid is used to keep the refrigerated space at -35°c by rejecting waste heat to cooling water that enters the condenser at 18°c at a rate of 0.25 kg/s and leaves at 26°c. the refrigerant enters the condenser at 1.2 mpa and 50°c. if the compressor consumes 3.3 kw of power, determine (a) the mass flow rate of the refrigerant, (b) the refrigeration load, (c) the cop, and (d) the minimum power input to the compressor for the same refrigeration load.