Question

energy efficiency = useful energy output/total energy input x 100 (%) if a power plant uses 100 units of energy to create electricity and the useful output is 5 units, what happens to the other 95% of the energy input? its lost mostly as heat. its lost as a liquid. its lost as a gas.

Explanation:

In energy conversion (like in power plants), the law of energy conservation applies, and energy not converted to useful output (here, electricity) is typically lost as heat due to inefficiencies in the conversion process. Loss as liquid or gas is not a typical way energy is lost in such conversions, while heat loss is common in energy - conversion systems.

Answer:

A. It's lost mostly as heat.