Question

In a diesel engine, hot exhaust gases ignite the incoming fuel fumes to keep the engine going, without the assistance of any electrical systems.Which of the following states why this does not violate the law of conservation of energy?A. The frictional forces inside the engine are low.B. The fuel continues to provide chemical energy.C. The heat required to light the fuel comes from the friction in the engineD. The engine is efficient enough to convert energy from chemical to mechanical and vice versa.

Answer 1

B. The fuel continues to provide chemical energy.

Explanation:

In a diesel engine, hot exhaust gases ignite incoming fuel fumes to keep the engine running, without the aid of any electrical system.

This does not violate the law of conservation of energy, because the incoming fuel vapors can be burned by using this heat and releasing a certain amount of energy again. The largest amount of energy is used to perform mechanical work and the left is used to ignite the incoming fuel.

This does not violate the law of conservation of energy, because the incoming fuel continues to provide chemical energy.