1. Linear Momentum Chapter 7

2. 7-1 Momentum & Its Relation to Force Linear momentum-product of the mass and its velocity Momenta – plural for momentum A vector quantity-Why?

3. Units are kgm/s and there is no short hand replacement

4. A force is required to change the momentum (velocity) of an object. Newton’s 2 nd law was originally written in terms of momentum and his original statement written in modern language is: The rate of change in momentum of an object is equal to the net force applied to it.

5. ΣF=Δp/Δt Where ΣF is the net force Δp is the change in momentum Δt is the time interval

6. 7-2 Conservation of Momentum The sum of the momentum before an event is equal to the sum of the momentum after the event

7. Impulse Catching a ball Landing on the ground Hitting a tennis ball Hitting a golf ball

8. 7-3 Collisions & Impulse  =m  v F= ma a=  v/t F  t=m  v Impulse= F  t (Average Force)

9. 7-4 Conservation of Energy & Momentum in Collisions If the total kinetic energy before the collision is equal to the total kinetic energy after the collision the collision is elastic. If the kinetic energy is lost and changed into another form of energy the collision is inelastic.