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A diatomic ideal gas is used in a Carnot...

A diatomic ideal gas is used in a Carnot engine as the working substance. If during the adiabatic expansion part of the cycle the volume of the gas increase from V to 32V, the efficiency of the engine is

A

`0.25`

B

`0.5`

C

`0.75`

D

`0.99`

Text Solution

Verified by Experts

The correct Answer is:
C
`T_(B) = T_(1) , T_(C) = T_(2) , gamma= 1.4 V_(B) = V ,V_(C) = 32V`
`T_(B)V_(B)^(gamma-1)= T_(C)V_(C)^(gamma-1)`
`(T_(C))/(T_(B)) = (T_(2))/(T_(1)) = ((V_(B))/(V_(C)))^(gamma-1)= ((1)/(32))^(gamma-1) = (1)/(4)`
`eta=1- (T_(2))/(T_(1)) = 1- (1)/(4) =(3)/(4)= 0.75`
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ALLEN -GEOMETRICAL OPTICS-EXERCISE - 05 (A)
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