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a bar that goes through the center of a wheel

fixed pulley

a pulley that stays attached in one place


A push, pull or lift


the object that a lever rests on


a wheel with bumps around its edge


the force that pulls everything toward the earth.

inclined planes

a flat surface with one end higher than the other.


a stiff bar used to push,pull,or lift an object


a wheel that has a rope looped around it. The rope fits in a groove that runs around the edge of the wheel


a simple mahcine that looks like a nail with ridges on it.

simple machines

a machine with few moving parts


two inclined planes put together. Nails and shovels are wedges


a round object that turns on an axle


using force to move an object from one place to another

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