Pulleys are another example of a simple machine.

But even "just" changing the direction of the force is important. A person can usually pull down with a greater force than that person can lift.

Pulleys can also be used in combination to greatly multiply the force that is exerted. When pulleys do this, that "input force" will move through a much greater distance. Simple machines can increase the force applied; they can not increase the amount of work done.



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