Linear Momentum AP Physics Chapter 7 Linear Momentum

Linear Momentum AP Physics Chapter 7

Linear Momentum 7. 1 Momentum and Its Relation to Force

7. 1 Momentum and Its Relation to Force Linear momentum – product of an objects mass and its velocity Unit is a kg*m/s The quantity is only useful when discussing collisions 7 -1

7. 1 Momentum and Its Relation to Force Impulse 7 -1

7. 1 Momentum and Its Relation to Force Impulse 7 -1

7. 1 Momentum and Its Relation to Force Impulse Or 7 -1

7. 1 Momentum and Its Relation to Force In a collision, to decrease force, we increase time of the collision Air Bags Consumer Report 7 -1

Linear Momentum 7. 2 Conservation of Momentum

7. 2 Conservation of Momentum Two kinds of collisions 1. Perfectly elastic – objects bounce apart 2. Perfectly inelastic – objects stick together 7 -2

7. 2 Conservation of Momentum In reality collisions are a combination of the two. Law of Conservation of Momentum – in a closed system, momentum is conserved in a collision 7 -2

7. 2 Conservation of Momentum 7 -2

7. 2 Conservation of Momentum In an inelastic collision 7 -2

7. 2 Conservation of Momentum In an explosion The reverse of a Inelastic collision 7 -2

Linear Momentum 7. 3 Conservation of Momentum in Collisions

7. 3 Conservation of Energy and Momentum Energy (mechanical) is conserved in an elastic collision So 7 -3

7. 3 Conservation of Energy and Momentum Any collision in which energy is lost, is considered inelastic. 7 -3

Linear Momentum 7. 4 Collisions in Two Dimensions

7. 4 Collisions in Two Dimensions inelastic collisions in two dimension As always each dimension is treated independently Then use vector addition to calculate the final answer 7 -4

7. 4 Collisions in Two Dimensions Momentum practice 7 -5

Linear Momentum 7. 5 Center if Mass

7. 5 Center of Mass Even if an object rotates there is one point that moves in the same that a particle would move if subject to the same force. 7 -5

7. 5 Center of Mass Center of mass – the point that does not rotate Java Applet Center of gravity – the point at which the force of gravity can be considered to act 7 -5