AP Physics Physics: Momentum, Impulse & Collisions

Question 1

What is the momentum of a 5 kg object moving at 10 m/s?

Accepted Answer

50 kg·m/s

Answer

2 kg·m/s

Answer

15 kg·m/s

Answer

0.5 kg·m/s

Question 2

The impulse-momentum theorem states that the net impulse on an object equals:

Accepted Answer

The change in momentum

Answer

The change in kinetic energy

Answer

The net force times distance

Answer

The work done on the object

Question 3

A net force of 100 N acts on a 0.5 kg ball for 0.05 s. What is the magnitude of the impulse?

Accepted Answer

5 N·s

Answer

2,000 N·s

Answer

0.5 N·s

Answer

50 N·s

Question 4

Which of the following is a vector quantity?

Accepted Answer

Momentum

Answer

Speed

Answer

Kinetic energy

Answer

Mass

Question 5

A 2 kg object increases its velocity from 3 m/s to 7 m/s. What impulse was applied?

Accepted Answer

8 N·s

Answer

20 N·s

Answer

4 N·s

Answer

14 N·s

Question 6

Why do airbags reduce injury in car crashes?

Accepted Answer

They increase the time over which the impulse acts, reducing the average force

Answer

They increase the force of impact

Answer

They decrease the total change in momentum

Answer

They convert all kinetic energy into heat

Question 7

A net force of 20 N acts on a 4 kg object for 3 seconds. What is the resulting change in velocity?

Accepted Answer

15 m/s

Answer

5 m/s

Answer

60 m/s

Answer

0.27 m/s