1. Newton’s 3rd Law

2. Newton’s 3rd Law of Motion
Whenever one object exerts a force on a second object,
the second object exerts an
equal and opposite force
on the first.
For every action there is an equal and opposite reaction
Action-reaction
Force Pairs

3. Action-Reaction Forces come in pairs
Action: If you push on a table with 10 N
Reaction: the table pushes back on you with 10 N
In the opposite direction

4. Example #1 Action: A baseball pushes a glove to the left with 8 N.
What is the reaction force?
Reaction: A glove pushes a baseball to the right with 8 N.

5. Example: Newton’s 3rd Law
Ex: Bird uses its wings to fly. Action: Wings push air downwards with 10 N Reaction: Air pushes the bird upwards with 10 N Equal Force in opposite directions

6. Example: Newton’s 3rd Law
Ex: Interaction between a baseball and bat Action: Baseball forces the bat to the left at 12 N Reaction: The bat forces the ball to the right 12 N
Action-reaction
Force Pairs

7. Example: Newton’s 3rd Law
Ex: Interaction between tires on car and road Equal Force in opposite directions
Action-reaction
Force Pairs
For every action there is:
an equal (in size) & opposite (in direction) reaction

8. Example: Newton’s 3rd Law
Ex: Interaction between ball and Earth
Action: Earth pulls down on ball
Reaction: Ball pulls up on Earth
Equal Force in opposite directions

9. 3rd Law pHet