For increasing the efficiency of Carnot's engine, which of the folowing is most effective:

Options

A. increasing the temperature of source by `80^(@)C`
B. decreasing temperature of sink by `80^(@)C`
C. increasing temperature of source by `40^(@)C` and decreasing temperature of sink by `40^(@)C`
D. all the above steps are equally effective.

Answer

B

Explanation

`n=1-(T_(2))/(T_(1))` For increasing of `eta` decreasing the value of
`T_(2)` is most effective.
Thus, correct choice is (b).