Question

choose the correct answer.

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 processes like in a power plant, according to the laws of thermodynamics, energy is not destroyed but transformed. When converting energy to electricity, a significant portion (here 95%) is lost. In most power - plant operations (such as fossil - fuel or nuclear power plants), the inefficiencies result in heat being the major form of energy loss. For example, in a coal - fired power plant, after the chemical energy in coal is converted to thermal energy (heat) to produce steam, and then to mechanical energy (turbine rotation) and finally to electrical energy, a large amount of heat is dissipated to the environment (e.g., through cooling towers). Liquids (unless there is a specific liquid - based energy loss mechanism, which is not common in general power - plant energy - loss scenarios) and gases (again, not the typical major form of energy loss in the context of overall energy - conversion inefficiency) are not the main forms of this 95% energy loss.

Answer:

It's lost mostly as heat.