A carnot engine is designed to operate between `480K` and `300K`. Assuming that the engine actually produces, 1.2 KJ` of mechanical energy per Kcal of heat absorbed. Compare the actual efficiency with the theoretiacal maximum efficiency.

Answer

`16:21`

Explanation

Here, `T_(1)= 480K, T_(2)= 300K`
Theoretical max. efficiency
`eta=1-(T_(2))/(T_(1))=1-(300)/(480)=3/8= 37.5%^`
Practical efficiency,
`eta'=W/Q=(1.2KJ)/(1kcal)=(1.2xx10^(3)J)/(10^(3)xx4.2J)=2/7`
`(eta')/(eta)=(2//7)/(3//8)=2/7xx8/3=(16)/(21)`