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Consider the following statements for refrigeration and air-conditioning: 1) In refrigerating machine, the heat exchanger that absorbs heat is connected to a conditioned space. 2) A refrigerating cycle operating reversibly between two heat reservoirs has the highest coefficient of performance. 3) The lower the refrigeration required and the higher the temperature of heat rejection to the surroundings, the larger the power consumption. Which of the above statements are correct?

Consider the following statements for refrigeration and air-conditioning: 1) In refrigerating machine, the heat exchanger that absorbs heat is connected to a conditioned space. 2) A refrigerating cycle operating reversibly between two heat reservoirs has the highest coefficient of performance. 3) The lower the refrigeration required and the higher the temperature of heat rejection to the surroundings, the larger the power consumption. Which of the above statements are correct? Correct Answer 1, 2 and 3

Explanation:

Statement ‘1’ refers to evaporator.

Statement '2' refers to reversible cycle thus maximum coefficient of performance.

For lower requisite refrigeration and higher temperature of heat-rejection, the power consumption would increase.

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So, Power requirement will increase if temperature of heat rejection increases

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