Re: third law forces cancel?

[Tom Bross <Tbross@AOL.COM>]

In a message dated 10/11/2004 12:38:24 PM Eastern Daylight Time,
larry.smith@SNOW.EDU writes:

> I have told students that we don't
> even add forces on different objects together

You are right.  Third law forces act on different bodies.  Body A exerts a
force on body B and body B therefore exerts a force back on body A, equal in
magnitude but opposite in direction..(I don't know enough to argue the
causality--who initiated and who responded, or neither.)

I always draw the bodies in question in separate diagrams to keep it clear
which forces are acting on which body.