How is mechanical efficiency calculated?

Mechanical efficiency is a crucial concept in understanding how effectively a machine converts input energy into useful output energy. It is calculated by taking the ratio of output work to input work and then multiplying by 100 to express it as a percentage. This calculation provides a clear view of how much of the input energy is being utilized for useful work, which helps in assessing the performance and efficiency of mechanical systems.

This method of calculating efficiency allows comparisons between different machines or processes, highlighting how losses such as friction or heat dissipation can affect overall performance. A higher mechanical efficiency percentage indicates that a larger portion of the input energy is converted into useful work, which is a desirable quality in any mechanical system.

Other options present variations of this calculation that do not yield the correct mechanical efficiency value or mix the terms inappropriately. For instance, simply stating output work over input work without converting it into a percentage does not convey efficiency in a commonly understood manner.