Newton’s 3rd Law

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

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

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.

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

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

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

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

3rd Law pHet