Momentum and impulse grade 12 physical sciences

This is a presentation on the topic of momentum and impulse for physical sciences grade 12 learners , it focuses on the part of conservation of momentum and elastic and inelastic collisions

1. Momentum & IMPULSE GRADE 12 PHYSICAL SCIENCES PRESENTED BY: MF KOMANE

2. Introduction Search booklet.com and enter the game pin provided to play the game.

3. Learning objectives Define an isolated system State and apply conservation of linear momentum Distinguish between elastic and inelastic collision

4. Isolated systems A system in which the net external force is zero Isolated system exclude external forces outside the collision for example, frictional force It includes only the internal forces such as the contact force between the objects

5. Isolated systems

6. Conservation of linear momentum The total linear momentum of an isolated system remains constant (conserved) OR In an isolated system the total momentum before a collision is equal to the total momentum after the collision. Use the equations when applying conservation of momentum: M1v1i + M2v2i=M1v1f+M2v2f

7. Elastic collision Elastic collision is a collision in which the colliding objects do not stick together Both momentum and kinetic energy is conserved The equation used: M1vi+ m2v2i = m1v1f + m2v2f
Where vi is the velocity before the collision and vf is the velocities after the collision.

8. Examples of elastic collision

9. Consider the animation on the right showing an elastic collision between two objects. What is the initial velocity of the blue ball? Momentum is conserved, so the net momentum before collision equals the net momentum after collision. Since the orange ball is stationary its momentum is 0. The only momentum of the system before collision is due to the moving blue ball. So we can write the expression below.
Mass(blue ball) X velocity(blue ball) = Mass(orange ball) X velocity(orange ball)
=> 0.01 Kg X V(blue ball) = 0.001 Kg X 30 m/s.
=> V(blue ball) = (0.001 Kg X 30 m/s) 0.01 Kg
=> V(blue ball) = 3 m/s

10. Inelastic collisions It is a collision in which the colliding objects stick together after collision Momentum is conserved, while kinetic energy is not conserved The equation used: M1v1i + m2v2i = (m1 + m2) vF

11. Examples of inelastic collision Determine the mass of the blue ball using conservation of linear momentum M1v1i + M2v2i  = (M1+M2) vf => 6Kg X 2m/s = (6Kgx M1) 1m/s => 12=6M1 => M1= 6kg => so the blue ball also has a mass of 6 Kg.

12. momentum Identify the number and type of collisions in the following animation

13. Proving if a collision is elastic or inelastic Calculate the kinetic energy before and the kinetic energy after If the kinetic energy after is not equal to the kinetic energy before The collision is inelastic

14. PheT simulations Let’s us explore simple elastic and elastic collisions https://phet.colorado.edu/en/simulations/legacy/collision-lab

15. Summary… Lets watch the you tube video https://youtu.be/jRliH0jVilM?si=W308UsMpAKnE3nZ_

16. Think-share pair activity In a piece of paper write any interesting thing you learned in todays lesson and exchange with your desk mate to share with the whole class