simple machines
incline plane
a sloping ramp up which heavy loads can be raised by ropes or chains.
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screw

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a short, slender, sharp-pointed metal pin with a raised helical thread running around it and a slotted head, used to join things together by being rotated so that it pierces wood or other material and is held tightly in place
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wheel and axle
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a simple lifting machine consisting of a rope that unwinds from a wheel onto a cylindrical drum or shaft joined to the wheel to provide mechanical advantage.

