Change in Momentum and Impulse - AP Physics 1

1. A 3 kg object accelerates from rest to 10 m/s. Calculate the impulse.

   30 Ns. Change in momentum: $3(10-0) = 30$ kg·m/s = 30 Ns.

2. What is the final velocity of a 4 kg object after a 16 Ns impulse, starting from rest?

   4 m/s. Final velocity: $v = \frac{J}{m} = \frac{16}{4} = 4$ m/s.

3. What does the area under a force-time graph represent?

   Impulse. Area under force-time curve equals impulse.

4. What is an example of an impulse-momentum scenario in sports?

   A soccer ball being kicked. Force applied over short time changes ball's momentum.

5. What is the impulse on a 10 kg object that comes to rest from 20 m/s?

   -200 Ns. Change in momentum: $10(0-20) = -200$ kg·m/s = -200 Ns.

6. If a baseball experiences an impulse of 10 Ns, which physical quantity changes?

   Momentum. Impulse always changes momentum of objects.

7. If an object is at rest, what is its initial momentum?

   0 kg·m/s. Stationary objects have zero momentum.

8. Find the impulse given to a 3 kg object if it accelerates from 0 to 4 m/s.

   12 Ns. Change in momentum: $3(4-0) = 12$ kg·m/s = 12 Ns.

9. What is the impulse on a 50 kg object that changes velocity from 10 m/s to 0 m/s?

   -500 Ns. Change in momentum: $50(0-10) = -500$ kg·m/s = -500 Ns.

10. What is the formula for momentum?

    $p = m \times v$. Mass times velocity gives momentum.

11. Calculate the change in momentum for a 5 kg object with an initial velocity of 2 m/s and final velocity of 5 m/s.

    15 kg·m/s. Change in momentum: $5(5-2) = 15$ kg·m/s.

12. What is the effect of increasing the time over which a force acts on an object?

    Increase in impulse. Longer time allows greater impulse for same force.

13. What is the effect of impulse on a moving object's velocity?

    Changes the velocity. Impulse changes momentum, which affects velocity.

14. Calculate the final velocity of a 10 kg object after an impulse of 40 Ns is applied, starting from rest.

    4 m/s. Final velocity: $v = \frac{J}{m} = \frac{40}{10} = 4$ m/s.

15. State Newton's second law in terms of momentum.

    $F = \frac{\triangle p}{\triangle t}$. Force equals rate of momentum change.

16. How does impulse relate to force when time is constant?

    Impulse is directly proportional to force. $J = F\triangle t$, so impulse increases with force.

17. What is the impulse experienced by a 2 kg object accelerating from 3 m/s to 7 m/s?

    8 Ns. Change in momentum: $2(7-3) = 8$ kg·m/s = 8 Ns.

18. A force of 5 N acts on an object for 6 s. What is the impulse?

    30 Ns. Impulse equals force times time: $5 \times 6 = 30$ Ns.

19. If a force acts for a very short time, what is this force often called?

    Impulsive force. Large force acting briefly, like collision forces.

20. What is the unit of impulse in the SI system?

    Newton-second (Ns). Force in Newtons times time in seconds gives Newton-seconds.

21. What is the initial momentum of a 20 kg object moving at 3 m/s?

    60 kg·m/s. Momentum equals mass times velocity: $20 \times 3 = 60$ kg·m/s.

22. What is the momentum change of a 4 kg object that decelerates from 9 m/s to 3 m/s?

    -24 kg·m/s. Change in momentum: $4(3-9) = -24$ kg·m/s.

23. Define momentum.

    Momentum is the product of mass and velocity. Fundamental quantity describing motion of objects.

24. State the formula for impulse in terms of change in momentum.

    $J = \triangle p$. Impulse-momentum theorem states impulse equals momentum change.

25. If the impulse is 25 Ns and time is 5 s, what is the average force exerted?

    5 N. Average force equals impulse divided by time: $\frac{25}{5} = 5$ N.

26. Calculate the change in momentum if a 25 kg object accelerates from 2 m/s to 6 m/s.

    100 kg·m/s. Change in momentum: $25(6-2) = 100$ kg·m/s.

27. Identify the physical quantity that impulse changes.

    Momentum. Impulse directly changes an object's momentum.

28. What is the formula for impulse in terms of force and time?

    $J = F \times \triangle t$. Impulse equals force multiplied by time interval.

29. Find the impulse required to stop a 15 kg object moving at 8 m/s.

    -120 Ns. Change in momentum: $15(0-8) = -120$ kg·m/s = -120 Ns.

30. State the unit of momentum in the SI system.

    Kilogram meter per second (kg·m/s). Mass in kg times velocity in m/s.

31. Describe the relationship between impulse and momentum.

    Impulse equals change in momentum. Impulse-momentum theorem connects force and motion.

32. What is the effect of increasing the force applied on an object over a given time?

    Increase in impulse. Greater force produces larger impulse for same time.

33. What is the change in velocity if a 30 Ns impulse is applied to a 5 kg object?

    6 m/s. Change in velocity: $\triangle v = \frac{J}{m} = \frac{30}{5} = 6$ m/s.

34. How does impulse relate to the change in velocity for a constant mass?

    Impulse equals mass times change in velocity. For constant mass, $J = m\triangle v$.

35. If a car's speed decreases from 30 m/s to 10 m/s, what is the change in momentum if mass is 1000 kg?

    -20000 kg·m/s. Change in momentum: $1000(10-30) = -20000$ kg·m/s.

36. Calculate the final momentum of a 2 kg object moving at 5 m/s.

    10 kg·m/s. Final momentum equals mass times final velocity.

37. If a force of 10 N acts for 4 s, what is the impulse imparted?

    40 Ns. Impulse equals force times time: $10 \times 4 = 40$ Ns.

38. What does a larger impulse indicate in terms of force and time?

    A larger force or longer duration. Greater impulse means stronger or longer force application.

39. Calculate the force exerted if an impulse of 15 Ns is applied over 3 s.

    5 N. Force equals impulse divided by time: $\frac{15}{3} = 5$ N.

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