1. Momentum and Collisions Momentum and Impulse

2. Momentum and Impulse Imagine an automobile collision in which a 1960s car traveling at 15 mph collides with a car at rest. Now imagine the same collision with a 2009 model car. In both cases, the car and passengers are stopped abruptly. Imagine an automobile collision in which a 1960s car traveling at 15 mph collides with a car at rest. Now imagine the same collision with a 2009 model car. In both cases, the car and passengers are stopped abruptly. List the features in the newer car that are designed to protect the passenger and the features designed to minimize damage to the car. List the features in the newer car that are designed to protect the passenger and the features designed to minimize damage to the car.

3. Momentum Momentum (p) is proportional to mass and velocity. Momentum (p) is proportional to mass and velocity. A vector quantity- has direction A vector quantity- has direction SI Units: kg m/s SI Units: kg m/s

4. Greater changes in momentum (Δp) require more force (F) or more time (Δt) Greater changes in momentum (Δp) require more force (F) or more time (Δt) A loaded truck requires more time to stop. A loaded truck requires more time to stop. – Greater Δp for truck with more mass – Greater Δp for truck with more mass – Same stopping force – Same stopping force

5. Impulse Impulse = Force multiplied by the amount of time it acts over. Impulse = Force multiplied by the amount of time it acts over. Impulse = Change in momentum Impulse = Change in momentum

6. Example Calculate the momentum of the give objects. Example Calculate the momentum of the give objects. a. Momentum of basketball; A basketball ball having 2kg mass and 6m/s velocity moves to the east a. Momentum of basketball; A basketball ball having 2kg mass and 6m/s velocity moves to the east b. Momentum of car; A car having 15m/s velocity and 1500kg mass moves to the north b. Momentum of car; A car having 15m/s velocity and 1500kg mass moves to the north c. Momentum of boy; A child having mass 25kg and velocity 2m/s moves to the west c. Momentum of boy; A child having mass 25kg and velocity 2m/s moves to the west

7. Drawings with answers http://www.physicstutorials.org/home/imp ulse-momentum/momentum http://www.physicstutorials.org/home/imp ulse-momentum/momentum http://www.physicstutorials.org/home/imp ulse-momentum/momentum http://www.physicstutorials.org/home/imp ulse-momentum/momentum