Lowering of condenser temperature (keeping the evaporator temperature constant) in case of vapour compression refrigeration system results in

ANS:A - increased COP.

In a vapor compression refrigeration system, the coefficient of performance (COP) is defined as the ratio of desired cooling effect to the work input: COP=Desired Cooling EffectWork InputCOP=Work InputDesired Cooling Effect​ Lowering the condenser temperature while keeping the evaporator temperature constant affects the performance of the refrigeration system.

• If the condenser temperature is lowered, the temperature difference between the condenser and the surroundings increases. This results in increased efficiency in rejecting heat to the surroundings, thus reducing the work input required for the compressor. As a result, the COP of the refrigeration system typically increases.