Scientifically speaking, "work" and "force" (or effort) are two different things. Work is the result of a force (a push or a pull) moving an object over some distance.

Look at the equation. If force and distance are small, like when I'm turning the pages in a book, then work is small. What would happen if the distance was zero? No work would be done, no matter how much force was applied. Pushing against a wall may use a lot of force, but unless the wall actually moves, no work is being done.

There are a lot of simple machines, like levers, pulleys, and ramps, that make it so that you don't need to use as much force to do the same amount of work. How do they do this? Well, they increase the distance over which the work is done. Did you ever sit on a see-saw with an adult much heavier than you? You know that there is no way you could lift the adult using just your arms. But by sitting on the very end of the see-saw, you are able to lift a person much heavier than yourself. The see-saw is a lever that helps you do the work by spreading the force you apply over a greater distance.

 

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