Question

choose the correct answer
a shovel is a type of machine. what do we call the work put into a machine?
work output
work input

Explanation:

In the context of machines (a topic in Physics, part of Natural Science), the work put into a machine is defined as work input. Work output is the work the machine does. So the correct term for work put into a machine is work input.

Answer:

work input (the option with "work input" text)