1. Chapter 5 Newton’s Third Law of Motion

2. Newton’s Laws For every action force there is an equal and opposite reaction force (You cannot touch without being touched) The 3 rd Law

3. Action-Reaction Force Pairs Never act on the same object

4. Defining Your System Two objects define a system for a Newton’s third law interaction. We are not considering (necessarily) the net force acting on an object. An object cannot exert a force on itself to cause an acceleration.

5. Action: rocket pushes on gases Reaction: gases push on rocket

6. Action: tire pushes on road Reaction: road pushes on tire

7. Force accelerating bulletRecoil force a = F/ m

8. Vectors an arrow drawn to scale used to represent a vector quantity Vector Notation

9. Components of a Vector x y

10. Vector Addition

11. Notes on Components Components are vectors

12. Vector Subtraction

13. Chapter 5 Review Questions

14. A bug and a car collide. Which experiences the greater force? (a) bug (b) car (c) neither, they both experience the same magnitude of force

15. Consider hitting a baseball with a bat. If we call the force applied to the ball by the bat the action force, identify the reaction force. (a) the force applied to the bat by the hands (b) the force applied to the bat by the ball (c) the force the ball carries with it in flight (d) the centrifugal force in the swing (b) the force applied to the bat by the ball