Question

It has been suggested that a heat engine could be developed that made use of the fact that the temperature several hundred meters beneath the surface of the ocean is several degrees colder than the temperature at the surface. In the tropics, the temperature may be 6 degrees C and 22 degrees C, respectively. What is the maximum efficiency (in %) such an engine could have?

Answer 1

Answer:

efficiency = 5.4%

Explanation:

Efficiency of heat engine is given as

$\eta = \frac{W}{Q_{in}}$

now we will have

$W = Q_1 - Q_2$

so we will have

$\eta = 1 - \frac{Q_2}{Q_1}$

now we know that

$\frac{Q_2}{Q_1} = \frac{T_2}{T_1}$

so we have

$\eta = 1 - \frac{T_2}{T_1}$

$\eta = 1 - \frac{273+6}{273+22}$

$\eta = 0.054$

so efficiency is 5.4%