A carnot engine working between 300K and 400K has 800 j of useful work . The amount of heat enegy supplied to the engine from the source is

Options

A. 2400j
B. 3200j
C. 1200j
D. 3600j

Answer

b

Explanation

As, `eta=1-frac(T^(2))(T^(1))=frac(W)(Q)thereforeQ=W//(1-frac(T^(2))(T^(1)))`
Here, `T_(1)=400K,T_(2)=300K,W=800J`
`thereforeQ=frac(800)((1-frac(300)(400)))=frac(800)((1//4))=3200J`