1. Newton’s Third Law
For every action, there is an equal and opposite reaction
When one object exerts a force on a second object, the second object simultaneously exerts a force equal in magnitude and opposite in direction on the first object.

2. Newton’s Third Law

3. Newton’s Third Law

4. Newton’s Third Law
Mathematically stated, if object 1 pushes on object 2 with a force F12, then object 2 pushes on object 1 with a force F21 so that
F21 = −F12

5. Newton’s Third Law Other examples:
Trees, rocks, buildings, and cars, even the atmosphere, are all subject to the downward force of gravity.
In all cases Earth exerts an equal and opposite upward push on those objects.