Physics CP Momentum Review 1.
Two cars with the same mass are moving, but Car B is moving at twice the speed of Car A. Car B’s
momentum is _______________ Car A’s momentum.
a. twice b. half
2.
c. four times
d. equal to
Two cars move down a hill at the same constant velocity. Car C is much larger than Car D. The car
that has greater momentum is:
a. Car D because it has less mass
b. Car C because it has more mass.
c. Both cars have equal momentum.
3.
A cannon shoots a cannon ball. After the explosion, the momentum of the cannon is
_______________ the momentum of the cannon ball.
a. equal to b. greater than
4.
c. less than
A car is idling in the parking lot. Which of the following statements is TRUE?
a. The car has both inertia and momentum. c. The car has inertia, but no momentum.
b. The car neither inertia nor momentum. d.
The car has momentum, but no inertia.
5.
What is the momentum of a 2 kg toy car travelling at 3 meters/second
a. 0.67 kg m/s
6.
b. 6 kg m/s
c. 1.5 kg m/s d. 0 kg m/s
Which has a greater momentum: a 15 kg object moving at 4 m/s (Object A) or a 30 kg object
moving a 2 m/s (Object B)?
a. Object A b. Object B c. Both have the same momentum.
7.
Which would produce a greatest change in momentum of an object?
a. A 100 N force applied over 5 seconds.
b. A 50 N force applied over 10 seconds.
c. A 1 N force applied over 500 seconds.
d. All will produce the same change in momentum.
8.
An object has an initial momentum of 12 kg m/s to the right. A force of 10 N to the right is applied
to the object for 2 seconds. What is the final momentum of the object?
a. 20 kg m/s
9.
b. 32 kg m/s
c. 12 kg m/s
d. ‐8 kg m/s
A 5 kg object has an initial velocity of 20 kg m/s to the right. A leftward force of 20 N is applied
for 3 seconds. What is the final velocity of the object?
a. 160 m/s
b. 32 m/s
c. 8 m/s
d. 0 m/s
10. When an egg hits the floor, it will probably break. Yet if you drop an egg of the same mass onto a
sheet being held by students, it will not break. Why doesn’t the egg break on the sheet?
a. The egg’s change in momentum is less.
b. The impulse experienced by the egg is less.
c. The time it takes the egg to come to rest is shorter, so the force on the egg is smaller.
d. The time it takes the egg to come to rest is longer, so the force on the egg is smaller.
11. Suppose that you were involved in a head‐on collision and your airbag did not deploy. Instead,
your face hit a padded dashboard. How might the force on your face be different than if the airbag
had actually been deployed? Explain in as much detail as possible.
12. Two steel balls collide. Ball A has a mass of 2.0 kg and a velocity of 1.5 m/s to the right. Ball B
has a mass of 1.0 kg and a velocity of 2 m/s to the left. The balls collide elastically.
a. What is the total momentum of the system before the collision?
b.
c.
What will be the total momentum of the system after the collision?
After the collision, Ball A is observed to move to the left at 1.0 m/s. What is the final
velocity of Ball B?
13. Sam and Harry are each standing on skateboards on a “frictionless” surface.
Sam has a mass of 80
kg and Harry’s mass is 120 kg. The skateboards then gently push off of each other and each moves
backwards.
a.
b.
c.
What is the total momentum of the system before the explosion?
What will be the total momentum of the system immediately after the explosion?
Sam is observed to move to the left at 6 m/s. What is Harry’s velocity after the explosion?