Answer:
- <em>The energy put into a machine or device to make it work is named</em> <u>work input.</u>
Explanation:
<em>Machines </em>are devices to perform tasks with less effort or more easily. They can either increase the force applied or change the direction of the force or permit to apply the force at a distance.
The law of conservation of energy states that the energy is neither created nor destroyed, but when the machines do <em>work</em> some energy is dissipated in the form of heat, light or sound, due, mainly to friction.
In consequence, the <em>work output</em> is less than the <em>work input</em>.
A measure of energy use is efficiency. The efficiency is the ratio of the work output to the work input.