A Carnot engine takes `3 xx 10^(6)` cals of heat from a reservoir at `627^(@)C` and gives it to a sink at `27^(@)C`. The work done by the engine is:

Options

A. `4 cdot 2xx10^(6)J`
B. `16 cdot 8xx10^(6)J`
C. `8 cdot 4xx10^(6)J`
D. `3xx10^(6)J`

Answer

C

Explanation

`eta =1-(T_(2))/(T_(1))=1-(300)/(900)=(2)/(3)`
Work `=n cdot Q_(1)=(2)/(3) xx 3xx 10^(6)=2xx10^(6)` cal.
`=8 cdot 4xx10^(6)` J
`therefore` Correct choice is (c ).