1. LESSON LESSON INTRODUCTION Get Ready Before you begin, decide if you agree or disagree with each of these statements. As you view this presentation, see if you change your mind about any of the statements. What do you think? 4 Newton's Third Law

2. Get Ready LESSON LESSON INTRODUCTION Do you agree or disagree? If objects collide, the object with more mass applies more force. Momentum is a measure of how hard it is to stop a moving object. 4 Newton's Third Law

3. Key Concepts/Essential Questions LESSON LESSON INTRODUCTION 4 Newton's Third Law What is Newton’s third law of motion? Why don’t the forces in a force pair cancel each other? What is the law of conservation of momentum?

4. Vocabulary Watch out for these words! LESSON LESSON INTRODUCTION Newton’s third law of motion force pair momentum law of conservation of momentum 4 Newton's Third Law

5. LESSON LESSON INTRODUCTION 4 Newton's Third Law Why move up? Look at the photo at the beginning of the lesson. To reach the height she needs for her dive, this diver must move up into the air. Does she just jump up? No, she doesn’t. She pushes down on the diving board and the diving board propels her into the air. How does pushing down cause the diver to move up?

6. LESSON 4 Newton's Third Law

7. Lesson Review LESSON LESSON WRAP-UP Do you agree or disagree? If objects collide, the object with more mass applies more force. 4 Newton's Third Law Disagree. If two objects collide and exert a force on each other, the objects exert equal force on each other.

8. Lesson Review LESSON LESSON WRAP-UP Do you agree or disagree? Momentum is a measure of how hard it is to stop a moving object. 4 Newton's Third Law Agree. Momentum is the product of an object’s mass and velocity.

9. Key Concept/Essential Question Review LESSON LESSON WRAP-UP What is Newton’s third law of motion? 4 Newton's Third Law Newton’s third law of motion states that when one object applies a force on another, the second object applies an equal force in the opposite direction on the first object.

10. Key Concept/Essential Question Review LESSON LESSON WRAP-UP Why don’t the forces in a force pair cancel each other? 4 Newton's Third Law The forces of a force pair do not cancel because they act on different objects.

11. Key Concept/Essential Question Review LESSON LESSON WRAP-UP What is the law of conservation of momentum? 4 Newton's Third Law According to the law of conservation of momentum, momentum is conserved during a collision unless an outside force acts on the colliding objects.