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A Carnot engine, having an efficiency of...

A Carnot engine, having an efficiency of `eta=1//10` as heat engine, is used as a refrigerator. If the work done on the system is 10J, the amount of energy absorbed from the reservoir at lower temperature is

A

`99J`

B

`90J`

C

`1J`

D

`100J`

Text Solution

Verified by Experts

The correct Answer is:
B
Let `eta` is the efficiency of heat engine and `beta` is the corresponding coefficient of performance of a refrigerator working between the same temperature.
`beta = (1)/(eta) -1 = 10-1 = 9 "Also" beta=("Output")/("Input")`
=`"(Energy absorbed from the reservoir at lower temperature")/("Work done on the system")`
`beta = 9 = ("Energy absorbed")/(10J)`
So , energy absorbed = `90J`
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