Question

What is the maximum thermal efficiency for a heat engine?

Answer 1

The maximum thermal efficiency for a heat engine:

1. The temperature difference between the hot and cold ends divided by the temperature at the hot end equals the greatest theoretical efficiency associated with a heat engine (which is impossible for a practical engine to achieve).
2. The formula for thermal efficiency of a heat engine is written as $n_{max}=\frac{T_H-T_C}{T_H}$ where $T_{H}and{T}_C$ are the absolute temperature of the hot and cold reservoirs.
3. It is expressed on an absolute scale $Kelvin.$
4. Hence the efficiency of a Carnot engine with a hot reservoir of boiling water and a cold reservoir of ice cold water is $1-(273/373)=0.27$, converting just over a quarter of the heat energy into useful work.