Direction: Encircle the letter of the correct answer .
1. Which has more momentum, a heavy truck moving at 30 km/h or a light truck moving at
30 km/h?
A. heavy truck
C. Both have the same momentum
B. light truck
D. Cannot be determined.

2. A moderate force will break an egg. However, an egg dropped on the road usually breaks,
while one dropped on the grass usually does not break. This is because for the egg
dropped on the grass, _________.
A. the change in momentum is greater C. the time interval for stopping is greater
B. the change in momentum is less D. the time interval for stopping is less
3. The impulse experienced by a body is equal to the change in its ____________.
A. velocity B. kinetic energy C. momentum D. potential energy
4. In certain martial arts, people practice breaking a piece of wood with the side of their bare
hand. Use your understanding of impulse to explain how this can be done without injury
to the hand.
A. Given the same change in momentum, when the time interval is smaller the impact
force is bigger.
B. Given the same change in momentum, when the time interval is bigger the impact
force is bigger.
C. Given the same change in momentum, when the time interval is smaller the impact
force is smaller.
D. Given the same change in momentum, when the time interval is bigger the impact
force is smaller.
5. A lady tennis player hits an approaching ball with a force of 750 N If she hits the ball in
0.002 s, how much impulse is imparted to the tennis ball?
A. 0 N s B. 1.5 N s C. 3.0 N s D. 6.0 Ns
6. Which is a necessary condition for the total momentum of a system to be conserved?
A. Kinetic energy must not change. C. An object must be at rest.
B. No external force is present. D. Only the force of gravity acts on the system.
For numbers 7 and 8: Two 0.5 kg balls approach each other with the same speed of 1.0 m/s.
7. What is the total momentum of the system before collision?A. 0 B. 0.50 kg m/s C. 1.0 kg m/s D. -1.0 kg m/s
8. If there is no external force acting on the system, what the total momentum of the system
after collision?
A. 0 B. 0.50 kg m/s C. 1.0 kg m/s D. -1.0 kg m/s
9. Two billiard balls approach each other at equal speed. If they collide in a perfectly elastic
collision, what would be their velocities after collision?
A. Zero
B. Same in magnitude and direction
C. Same in magnitude but opposite in direction
D. Different in magnitude and opposite in direction
10. A 50-kg astronaut ejects 100 g of gas from his propulsion pistol at a velocity of 50 m/s.
What is his resulting velocity?
A. -0.10 m/s B. -0.50 m/s C. 0 m/s D. -100 m/s​