A Carnot engine is made to work between 200 ° C and 0 ° C first and then between 0 ° C to - 200 ° C . The ratio of efficiencies of the engine in the two cases is

Step-by-step solution

T 1 = 200 ℃ = 200 + 273 = 473 K T 2 = 0 ℃ = 0 + 273 = 27 3 K η 1 = 1 - T 2 T 1 = 1 - 273 473 = 200 473 Again, T 1 ′ = 0 ℃ = 0 + 273 K = 273 K T 2 ′ = - 200 ℃ = - 200 + 273 K = 73 K η 2 = 1 - T 2 T 1 ′ = 1 - 73 273 = 200 273 η 1 η 2 = 200 473 × 273 200 = 273 473 = 1 1.732