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In a refrigerator, the external work don...

In a refrigerator, the external work done on the working substance in one cycle is 20% of the energy extracted from the cold reservoir. The coefficient of performance of the refrigerator is

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The cofficient of performance of the refrigerator , `prop = Q_(c)/W = 1/ 0.2 = 5 `
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Refrigerator is an apparatus which takes heat from a cold body, work is done on it and the work done together with the heat absorbed is rejected to the source. An ideal refrigerator can be regarded as Carnot's ideal heat engine working in the reverse direction. The coefficient of performance of refrigerator is defined as beta = ("Heat extracted from cold reservoir")/("work done on working substance") = (Q_(2))/(W) = (Q_(2))/(Q_(1)- Q_(2)) = (T_(2))/(T_(1) - T_(2)) A Carnot's refrigerator takes heat from water at 0^(@)C and discards it to a room temperature at 27^(@)C . 1 Kg of water at 0^(@)C is to be changed into ice at 0^(@)C. (L_(ice) = 80"kcal//kg") What is the work done by the refrigerator in this process ( 1 "cal" = 4.2 "joule" )

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NAVNEET PUBLICATION - MAHARASHTRA BOARD-SOLVED PROBLEMS - I -KINETIC THEORY OF GASES AND RADIATION
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