Simple Machines - Physics answers questions

Simple Machines

An example of a screw, a wedge,
a wheel and axle, and a lever

May 2016 - Machines are ways to make it easier to do work. Many plants and animals have evolved natural machines like arm muscles (a kind of lever) or teeth (a kind of wedge) or a bacteria's flagellum (a kind of screw). Many animals also make machines out of dirt, wood, and stone. People make machines too. There are six different kinds of simple machines. Many of the more complicated machines we use are made of combinations of these six simple ideas.

Learn by Doing - a computer game where you build simple machines

Bibliography and further reading about simple machines:

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Professor Carr

Karen Eva Carr, PhD.
Assoc. Professor Emerita, History
Portland State University

Professor Carr holds a B.A. with high honors from Cornell University in classics and archaeology, and her M.A. and PhD. from the University of Michigan in Classical Art and Archaeology. She has excavated in Scotland, Cyprus, Greece, Israel, and Tunisia, and she has been teaching history to university students for a very long time.

Professor Carr's PSU page

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