The pulley is a slotted wheel that rotates around a pin. When a rope or chain is run through the slot, the pulley can be used to change direction of a pull or to change the amount of force needed to lift or pull something.
The fixed pully below just changes the direction of a pull:
A moveable pulley can be used so you use less force but exert
it over a greater distance:
Examples of pulleys:
©2001 Jeff Goodman
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