Question

Can a heat engine be \[100{{\% }}\] efficient?

Answer 1

Hint: A heat engine is a machine that converts heat energy into mechanical work that people may use. The process is carried out with the help of a simple apparatus. The heat engine has a number of benefits as well as some drawbacks.

Complete step by step solution:
We know that efficiency is equal to capability. The efficiency of a heat engine is defined as the ratio of the temperature difference between the hot source and the temperature of the cold reservoir. It is also known as the heat engine's thermal efficiency.

The optimum efficiency of a heat engine can be achieved if the difference between the hot and cold reservoirs is as large as possible. There is no unit for efficiency. The thermal effectiveness of one heat machine may differ from that of another. The following are the efficiency of several heat engines:

For ocean thermal energy conservation, it is just \[{{3\% }}\] effective. Gasoline engines in automobiles are roughly \[{{25\% }}\] efficient. Similarly, coal-fired power stations have \[{{49\% }}\] efficiency. It is around \[{{60\% }}\] efficient for the combined cycle gas turbine.

Hence, a heat engine cannot be \[{{100\% }}\] efficient

Note: The heat engine is a device that converts heat into mechanical work. The ratio of the temperature difference between the hot source and sink to the temperature of the hot source is the efficiency of a heat engine. The heat engine's efficiency is determined by the temperature difference between a hot and a cold reservoir.