Answer:
[tex]\eta = 0.067[/tex]
Explanation:
Efficiency of the engine working between two thermal reservoirs is given by the equation
[tex]\eta = 1 - \frac{T_2}{T_1}[/tex]
[tex]T_2 = 4 degree[/tex]
[tex]T_2 = 4 + 273 = 277 K[/tex]
[tex]T_1 = 24 degree[/tex]
[tex]T_1 = 273 + 24[/tex]
[tex]T_1 = 297 K[/tex]
now by the above equation we can say
[tex]\eta = 1 - \frac{277}{297}[/tex]
[tex]\eta = 0.067[/tex]