Question

What is the maximum theoretical efficiency possible for a heat engine operating between a reservoir in which ice and water coexist, and a reservoir in which water and steam coexist? The pressure is constant at 1.0 atmosphere for both reservoirs.

Answer 1

Answer:

$\eta_{th} = 26.8\,\%$

Explanation:

The maximum theoretical efficiency for a heat engine is given by the Carnot's Cycle. The temperatures of the hot reservoir and the cold reservoir at 1.0 atmosphere are 373.15 K and 273.15 K, respectively. Then:

$\eta_{th} = \left(1 - \frac{T_{L}}{T_{H}} \right)\times 100\,\%$

$\eta_{th} = \left(1-\frac{273.15\,K}{373.15\,K} \right)\times 100\,\%$

$\eta_{th} = 26.8\,\%$