1. Momentum
Momentum Clip

2. Collisions
Newton’s third law tells us that any time two objects hit each other, they exert equal and opposite forces on each other.
The effect of the force is not always the same.

3. Momentum The quantity of motion an object has
Takes into account mass & velocity
Big objects have more momentum than smaller objects moving at the same speed
Commonly used in sports
“The Minnesota Vikings are showing a lot of momentum”
Players have a lot of momentum
Physis of football

4. Momentum
Momentum is the mass of an object times its velocity.

5. Momentum Momentum = mass*velocity (or speed)
Momentum symbol = P
Units are kg*m/s
P=m*v
A school bus with a mass of 1000kg is travelling at 20m/s. What is its momentum?

6. Example Problem #1
An airplane with a mass of 2,000kg is travelling at 100m/s. What is the momentum?

7. Example Problem #2
A turkey has a momentum of 50kg*m/s, and is running 10m/s. What is its mass?

8. Example Problem #3
A 10kg bowling ball has a momentum of 30kg*m/s. What is its velocity?

9. Example Problem #4
A lion is running to catch an antelope with a velocity of 30m/s. What is the momentum if the lion has a mass of 80kg?

10. Example Problem #5
The momentum of a duck waddling at 0.20m/s is 4 kg*m/s. What is the duck’s mass?

11. Law of Conservation of Momentum
Law of conservation of momentum: as long as interacting objects are not influenced by outside forces, the total amount of momentum is constant
Total momentum before interaction = total momentum after interaction

12. Example Problem
An astronaut at rest throws a 2 kg wrench away from her at a velocity of -10 m/s. If the astronaut’s mass is 100 kg, at what velocity does the astronaut move backward after throwing the wrench?
Find momentum before and after
p1 = p2 or m1v1 = m2v2
2*(-10) = 100*v2