The Screw

The screw is really just an inclined plane wrapped around a shaft.  To visualize this, cut a piece of paper in half diagonally and put magic marker on the cut edge (the hypotenuse).  This is an image of a hypotenuse. Now wrap the paper around a pencil, beginning with a flat edge. When the screw is turned on its axis, material rides up the threads, and rotational motion is transformed into a back and forth motion.

Example of screws:

©2001 Jeff Goodman

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