This document discusses impulse, momentum, and collisions. It covers momentum as a vector quantity equal to mass times velocity, and how the total momentum of an isolated system is conserved during collisions. It also introduces impulse as the change in momentum due to an external force, and describes perfectly elastic and inelastic collisions.

1. Contents
1. Impulse and Momentum
2. Collision in 2D and 3D
3. Practical Examples

2. IMPULSE and MOMENTUM
1. Momentum


What is the velocity of ball A after the collision?
What is conserved during the collision?

The total momentum is the sum of momentum of ball A and
momentum of ball B.

3. IMPULSE and MOMENTUM
1. Momentum

The total momentum of the system is conserved during the
collision.

Momentum is a vector. It has the same direction as
corresponding velocity.

4. IMPULSE and MOMENTUM
1. Momentum

Usually this equation is written in terms of components.

5. IMPULSE and MOMENTUM
1. Momentum
▪ A particle’s momentum is a vector quantity given by
p = mv.
This means that a generalized version of Newton’s Second law can
be rewritten as
Fnet = dp/dt
▪ The momentum of an object will change if there is a net external
force acting on it. This change of momentum is called impulse, J.

6. IMPULSE and MOMENTUM
1. Momentum
▪ Low of Conservation of Momentum:
◦ When the net external force on a system is zero, the total
momentum of the system remains constant.
◦ Useful to use when solving for the collisions between two bodies.
▪ A perfectly elastic collision :
▪ A perfectly inelastic collision :