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As long as I never refer to actions or reactions (I actively oppose thisIf only the first day, it is OK. But if permanently, then why?
the first day we talk about forces in my courses) ...
...I specify the following:
1) The two forces which constitute a Newton's Third Law Pair must act onThis is an excellent clarification which is frequently lacking in teaching. When a book is resting on a table, there is downward gravitational force (action) on the book from the Earth and the upward gravitational force (reaction) on the Earth from the book. We have a pair of action-reaction forces of the same kind applied to two different bodies.
different bodies
2) They must be of the same kind (friction, gravitation, contact forces, etc)
3) When considering the state of motion of a body, one must consider all
the forces on (and only the forces ON) that body by any other agent