Linear Momentum Practice Questions (page 2)

Updated on Sep 26, 2011


  1. No, speed could be zero or very small.
  2. Only when speed is zero, because there can be no zero moving mass.
  3. Yes, if the velocity is in the negative direction.
  4. They are the same.
  5. No, since impulse also considers the time of interaction.
  6. No, the time of interaction can be negligible and then the impulse tends to zero.
  7. 225 N · s
  8. Longer since the force then would be smaller.
  9. Because on the carpet, the time of interaction is longer and the force of impact is smaller.
  10. No, momentum is a quantity of state, while impulse measures a state change.
  11. When the object stops
  12. If the object moves at a constant speed, there is no change in momentum, so no impulse.
  13. F = 1,800 N
  14. The momentum being constant means that when we consider momentum a vector both the magnitude and the direction of the momentum have to be the same in the initial and final states.
  15. Since momentum is a vector, you can have the following situation:
  16. Linear Momentum

  17. Throw the ball in a horizontal direction.
  18. Yes, it would have more momentum.
  19. Yes. Because speed changes direction before and after collision and velocity, momentum and impulse will consider direction also.
  20. v2 after collision > v2 before collision
  21. vf = (v1 + v2)/2
  22. The speed of the bike will almost be unchanged and at most decrease by a small amount.
  23. Equal and opposite, because the final momentum has to be equal to the initial momentum, which was zero.
  24. Equal in magnitude, opposite in direction.
  25. No, the resultant immediately after collision is nonzero.
  26. Linear Momentum

  27. Yes, if the momenta of the two cars are equal and opposite.
  28. v1x = 120 m/s and v1y = 50 m/s
  29. Before explosion: ( –10.6; 10.6) m/s or 15 m/s at 135° with respect to the x-axis
  30. After collision, the first piece moves at (120; 50) m/s or 130 m/s at 23° with respect to the x-axis. The second moves at (–10; 0) m/s or 10 m/s at 1800 with respect to the x-axis, and the third piece moves at (0; 12) m/s or 12 m/s at 90° with respect to the x-axis.

  31. 0.05 kg, 0.25 kg, and 0.5 kg
View Full Article
Add your own comment