Which physics concept involves the ratio of output power to input power?

Efficiency is the concept that describes the ratio of output power to input power in any system. It measures how well an energy conversion process is performing, illustrating what portion of the input energy is converted into useful output energy. The formula for efficiency can be expressed as:

Efficiency = (Output Power / Input Power) x 100%

A high efficiency indicates that a large percentage of the input power is effectively converted into output power, minimizing waste. This concept is crucial in engineering, as it helps designers optimize systems to ensure they run effectively and sustainably, saving energy and reducing costs.

The other concepts, while related to energy and power, do not specifically address the ratio of output to input power in the same manner as efficiency does. Work refers to the energy transferred when a force is applied over a distance, power loss generally refers to energy that is lost (often as heat) in a system, and conservation of energy states that energy cannot be created or destroyed but only transformed from one form to another. None of these concepts inherently focus on the comparison of output and input power ratios like efficiency.