Newton's Third Law of Motion - actions and reactions
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Newton's Third Law of Motion

Ballet Leap

Newton's Third Law of Motion tells us that

For every action there is an equal and opposite reaction.

Everything moves relative to everything else. If you push somebody, the push forces her backwards, but it also forces you backwards - that's the equal and opposite reaction. Sometimes the thing you're pushing against is so big that you don't notice the reaction (like if you are pushing off from the ground, the Earth is too big for you to see that the Earth is also moving away from you), but the reaction is still there.

Bibliography and further reading about Newton's Laws:

Gravity
Momentum
Friction
Physics
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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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