Question

What happens to the energy not output by a machine​

Answer 1

Answer:

By using the energy conservation law, the input energy must be equivalent to the output energy.  If you measured output energy is lower than your input energy, you have lost that difference of energy either in mechanical inefficiency (friction, heat, etc.) or an energy sink.

Thus, the energy not output by the machine is lost in the process within the machine.

Cheers.