Which statement about simple machines is correct?

Responses

Simple machines increase the amount of work done.

Simple machines always reduce the force needed to do move a load.

Simple machines do not change the amount of work done.

Simple machines always increase the distance that force is applied to do work.

1 answer

The correct statement about simple machines is:

Simple machines do not change the amount of work done.

This is because the work input (force applied over a distance) is equal to the work output (the force exerted on the load over the distance moved by the load) in an ideal system, assuming no friction or energy losses. Simple machines can change the direction of force, reduce the amount of force needed, or increase the distance over which the force is applied, but they do not increase the total work done.