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The efficiency of a carnot engine eta = ...

The efficiency of a carnot engine `eta = 1/10`. This carnot engine used as refrigerator. If work done on system is 10 J, then heat absorbed from sink will be …….

A

100 J

B

99 J

C

90 J

D

1 J

Text Solution

Verified by Experts

The correct Answer is:
C
Efficiency of carnot engine
`eta=(T_1-T_2)/T_1=(Q_1-Q_2)/Q_1`
Coefficient of performance of refrigerator ,
`beta=Q_2/(Q_1-Q_2)`
`beta=(1-eta)/eta`
`therefore beta=(1-1/10)/(1/10)=(9/10)/(1/10)=9`
but `beta=Q_2/W`
`therefore Q_2=betaW`
`therefore Q_2=9xx10=90` J
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