Unit 9 Momentum: Worksheet 3

Date Pd

Key Concepts/ Relationships: What is the Law of Conservation of Momentum? (p. 63)

What do you know about the external forces on a system where momentum is conserved?

1. A 2,00 kg cannon fires a 5 kg cannonball with a speed of 100m/s. What is the recoil velocity of the cannon? a) Draw the initial and final diagram (include velocity vectors) Initial Diagram: Final Diagram:

b) List the given information: m1= m2=

Initial Velocity Final Velocity vi1= vi2= vf1= vf2= c) Apply the Conservation of Momentum to solve for the unknown: 2. A 2000kg car initially moving with a speed of 30 m/s collides and sticks to a 1500 kg car which is initially at rest. What is the final speed of the two cars immediately after the collision? a) Draw the initial and final diagram (include velocity vectors) Initial Diagram: Final Diagram:

Initial Velocity Final Velocity vi1= vi2= vf1= vf2= c) Apply the Conservation of Momentum to solve for the unknown:

3. A rifle with a mass of 3 kg fires a bullet with a mass of 0.01 kg. If the bullet is fired with a velocity of 400 m/s, what is the recoil velocity of the rifle? a) Draw the initial and final diagram (include velocity vectors) Initial Diagram: Final Diagram:

Initial Velocity Final Velocity vi1= vi2= vf1= vf2= c) Apply the Conservation of Momentum to solve for the unknown: 4. A 60 kg figure skater slides across the ice with a velocity of 4 m/s. This figure skater picks up a second 40 kg figure skater who was initially at rest on the ice, and they move off together. What is the final velocity of the two figure skaters? a) Draw the initial and final diagram (include velocity vectors) Initial Diagram: Final Diagram:

5. A 0.005 kg toy dart is fired from a 0.05 kg toy dart gun suspended by strings. When the toy gun is fired, it is observed that the toy gun recoils with a velocity of 2 m/s. What is the velocity of the toy dart? a) Draw the initial and final diagram (include velocity vectors) Initial Diagram: Final Diagram:

Initial Velocity Final Velocity vi1= vi2= vf1= vf2= c) Apply the Conservation of Momentum to solve for the unknown: 6. A 100 kg football player running to the right with a speed of 4 m/s collides and talkles a 80 kg player initially at rest. What is the final velocity of the two players after the collision? a) Draw the initial and final diagram (include velocity vectors) Initial Diagram: Final Diagram:

7. An astronaut whose mass is 80 kg carries an empty oxygen tank with a mass of 10. kg. He throws the tank away from himself with a speed of 2.0 m/s. With what velocity does he start to move off into space? a) Draw the initial and final diagram (include velocity vectors) Initial Diagram: Final Diagram: