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Re: Newton's 3rd Law

Tom K. McCarthy says:

What's wrong with the notion of action/reaction? By using concrete
examples to help the student experience Newton's 3rd Law, it seems quite
natural to describe these as action/reaction, and, consequently, we find
that forces aways occur in pairs.

I think that the problem is in the everyday usage of those words.
If you are not using physics-speak, then you would probably say something
action: I push the cart.
reaction: The cart moves.

In terms of the 3rd law, the reaction should be that the cart pushes back
on me. You *could* teach that there are 2 meanings for the word reaction,
the physics meaning and the everyday meaning. But it's probably easier to
avoid the confusing nomenclature altogether.

--James McLean
post doc