Question

What is the maximum possible efficiency of a heat engine operating between a reservoir at 28.0°C and one at 350°C? (Enter a number as a fraction or decimal.)

Answer should be e_C= ?

Answer 1

the maximum possible efficiency of a heat engine is possible if it is assumed to be a reversible heat engine so for a reversible heat engine the efficiency = work output /heat taken from the

source = Q₁ -Q₂/ Q₁ = 1 - Q₂/ Q₁ = 1 - T₂ / T₁(here Q₁ , T₁ are the heat taken from and temperature of the source and Q₂,T₂ are the heat rejected to and temperature of the sink)

==> T _source = 350 C = 350+273 K = 623 K

==> T _sink = 28 C = 28+273 K =301 K

efficiency = 1 - 301/623 = 0.51685