Question

The efficiency of a Carnot engine operating between the temperatures 1000 K and 300 K is

• A. 60%
• B. 70%
• C. 90%
• D. 80%

Hint:

Carnot efficiency depends only on the absolute temperatures of the reservoirs and represents the maximum possible efficiency for a heat engine.

Answer 1

The Correct Option is B

The efficiency of a Carnot engine is given by $\eta = 1 - \frac{T_2}{T_1}$, where $T_1$ is the temperature of the hot reservoir and $T_2$ is the temperature of the cold reservoir (in Kelvin). Here, $T_1 = 1000$ K and $T_2 = 300$ K. \[ \eta = 1 - \frac{300}{1000} = 1 - 0.3 = 0.7 \] The efficiency in percentage is $0.7 \times 100 = 70%$.