What is the coefficient of performance of a refrigerator that needs to maintain eatables at 9°C if the room temperature is 36°C?

Question

Question

This question was previously asked in

OSSC Soil Conservation Extension Worker Official Paper II 11 Feb 2022

Answer 1

The correct answer is 10.44.

Key Points

The coefficient of performance (COP) of a refrigerator is given by the formula COP = T_C / (T_H - T_C).
Here, T_C is the temperature of the cold reservoir (inside the refrigerator) and T_H is the temperature of the hot reservoir (room temperature).
The temperatures must be converted to Kelvin before using the formula. T_C = 9ºC + 273 = 282K and T_H = 36ºC + 273 = 309K.
Using the formula: COP = 282 / (309 - 282) = 282 / 27 = 10.44.

Important Points

The coefficient of performance (COP) is a measure of the efficiency of a refrigerator or heat pump.
The higher the COP, the more efficient the refrigerator is.
In this context, efficiency means how well the refrigerator can transfer heat from the inside to the outside with less work input.
It is important to always convert temperatures to Kelvin when using thermodynamic equations.