1. Conservation of Momentum
Chapter 3, Section 6
Conservation of Momentum

2. Date: HW: 3.6 PTG #1-16, pg. 319-320 Learning Objective:
Describe conservation of momentum in collisions
Success Criteria:
Calculate momentum in a system
Define conservation of momentum in words and equations
Do Now:
Quiz!
WDYS/WDYT pg. 310
Agenda:
Do Now
PhET/Investigate
Physics Talk
PTG
Summary/Quiz

3. Investigate:
Collision PhET

4. Mass of Object 1 (kg)
Mass of Object 2 (kg)
Velocity of Object 1 before collision (m/s)
Velocity of Object 2 before collision (m/s)
Mass of combined objects after collision (kg)
Velocity of combined objects after collision (m/s)
1.0
0.0
2.0
3.0

5. Momentum p=mv Before Collision After Collision
Momentum of Object 1 kg*(m/s)
Momentum of Object 2 kg*(m/s)
Momentum of Combined objects 1 and 2
kg*(m/s)

6. DO NOW:
Describe what you know about conservation of momentum.

7. Physics Talk 3.6 What is the Conservation of Momentum?
The total momentum before a collision, is equal to the total momentum after the collision if no external forces act on the system.

8. What is the equation for momentum?
What is the equation for conservation of momentum?
p=mv
p=momentum [kg*(m/s)]
m=mass (kg)
v=velocity (m/s)

9. Why is this equation written like this?
You added the masses after the collision because they stuck together

10. Pool ball example
Single cue ball hits a rack of 15 balls…momentum is conserved!
Total momentum before is equal to the total momentum after the collision
The balls move in new directions with new speeds, but the momentum stays the same!

11. Why is conservation of momentum important?
Used to investigate traffic accidents
If you know masses and velocities of two objects, you can predict the velocity after the collision…you can predict the future!

12. Practice Problems
PTG pg. 319 #1-16

13. Essential Questions LO and SC Reflection
Answer essential questions pg. 318

14. Quiz!