3. Momentum is a vector quantity That is defined as the product Of an object’s mass and velocity. p = mv

4. A 2250 kg pickup truck has a Velocity of 25 m/s to the east. What is the momentum of The truck? 56250 kg m/s

5. A 21 kg child is riding on a 5.9 kg Bike with a velocity of 4.5 m/s To the north west. What is the Total momentum of the child & bike Together? Just the child? Just The bike? 120 kg m/s94 kg m/s 27 kg m/s

6. A change in momentum Takes force and time. FΔt = Δp or FΔt = mv f - mv i The Impulse-Momentum Theorem

7. Impulse (for a constant external Force) is the product of the Force and the time over which It acts on an object. FΔt is called the Impulse.

8. A 1400 kg car moving westward With a velocity of 15 m/s Collides with a utility pole. It is then Brought to a stop in 0.30s. Find The magnitude of the force Exerted on the car during the Collision. 7 X 10 4 N

9. Stopping times and distances Depend on the impulse- Momentum theorem. A change in momentum over A longer time requires less force.

10. Angular momentum is the product Of a rotating object’s moment Of inertia and angular Speed about the same axis. L = Iω

11. Erica, 65kg, is spinning on a merry- Go-round that has a mass of 115kg, And a radius of 2m. She walks From the edge to the center. If The angular speed is initially 2 rad/s What is its angular speed when she Reaches a point 0.5m from The center? 3.9 rad/s

12. The angular impulse-momentum Theorem states that the angular Impulse on an object is equal To the change in the object’s Angular momentum. τΔt = L f - L i

13. The total momentum of all objects Interacting with one another Remains constant regardless of The nature of the forces Between the objects.

14. m 1 v 1i + m 2 v 2i = m 1 v 1f + m 2 v 2f The conservation of momentum Can be shown as a formula… Momentum is conserved in Collisions and for objects Pushing away from each other.

15. A 76 kg boater (Charlie), initially At rest in a stationary 45 kg boat, Steps out of the boat and onto the Dock. If Ryan moves out of the Boat with a velocity of 2.5 m/s, What is the final velocity Of his boat? v 2f = 4.2 m/s

16. An 85 kg fisherman jumps from a Dock into a 135 kg rowboat at rest On the west side of the dock. If the Velocity of the fisherman is 4.3 m/s to the west, what is the Final velocity of the Fisherman and the boat? 1.66 m/s to the west

17. There are two kinds of collisions: Those that bounce off of each other And those that stick together

18. A perfectly inelastic collision is a Collision in which two objects Stick together and move with A common velocity after Colliding. m 1 v 1i + m 2 v 2i = (m 1 +m 2 ) v f The formula for a perfectly Inelastic collision

19. An 1850 kg Cadillac stopped at a Light is struck from the rear by A Honda with a mass of 975 kg. The 2 cars become entangled. If the Honda was moving at 22 m/s to the north before, what Is the velocity of the entangled Mess after the collision? v f = 7.59 m/s to the north

20. A grocery shopper tosses a 9 kg Bag of dog food into a stationary 18 kg cart. The bag hits the cart With a horizontal speed of 5.5 m/s Toward the front of the cart. What is the final speed of the Cart and bag? 1.8 m/s

21. The law of conservation of Angular momentum states that If no external torque acts on an Object, then its angular momentum Does not change. L 1 = L 2 Iω = Iω