1

Find the momentum of a 150 kg object moving to the north at 16.0 m/s.

2

Find the velocity of a 60.0 kg object if its momentum is 300. kg m/s, up.

3

Find the mass of an object with a momentum of 1.90 × 10³ kg m/s, east, if its speed is 25.0 m/s.

4

A 1.50 × 10³ kg rocket speeds up from 385 m/s, N to 455 m/s, N. What impulse caused this change in momentum?

5

If the rocket from the previous question fired its engines for 30.0 seconds to speed up as it did, how much force did the engines exert?

6

If the previous rocket needs to slow down to 155 m/s, north and its engines can exert a force of 3500 N, how long will this take?

7

You are trying to close a door by throwing an object at it. If you can choose between throwing a 100 g super ball, which will bounce off the door, or a 100 g lump of clay, which will stick to the door, which would result in the larger final speed for the door? Both objects are thrown only once and at the same speed.

8

A 125 g ball is moving horizontally at 23.0 m/s, east. It strikes a wall, where a 12.0 N force is exerted on the ball for 0.400 s. What is the final velocity of the ball?

9

A 355 g ball is moving horizontally. It strikes a wall, where a 23.0 N force acting for 0.520 s causes the ball’s velocity to change to 16.3 m/s, south. What was the ball’s initial velocity?

10

A ball is moving horizontally at 18.9 m/s, west. It strikes a wall, where a 17.0 N force acts for 0.600 s, changing the ball’s velocity to 15.2 m/s, east. Find the mass of the ball.

11

Why does an egg thrown into a sheet “survive”, while one thrown against a brick wall does not? Be sure to use terminology from this chapter in your answer.

12

Is it possible for a 1 N force to bring a speeding bulldozer to a stop from a speed of 25 m/s? Explain why or why not. Be sure to use terminology from this chapter in your answer.

13

Is it possible to stop a speeding bulldozer in 0.100 second? Explain why or why not. Be sure to use terminology from this chapter in your answer.

14

Mass A (450 g) moves to the left at 12.0 m/s. It collides head-on with mass B (280 g) which is moving to the right at 9.50 m/s. After the collision, B is moving to the left at 15.0 m/s. Find the final velocity of A.

15

How much KE is lost in the collision from the previous question? What type of collision is it?

16

Two sandbags are floating toward each other in outer space. One is moving to the right at 10 m/s and the other is moving to the left at 20 m/s. The faster one is four times the mass of the slower one. They collide in a perfectly inelastic collision. What is the final velocity of the system?

17

Two equal mass objects move toward each other with equal speeds. They collide and move away from each other with the same speeds they had before colliding. What type of collision was this? How can you tell?

18

Two equal mass objects move toward each other with equal speeds. They collide and stick together, coming to a stop after colliding. What type of collision was this? How can you tell?

19

Two objects collide head-on. After the collision, the total KE of the system is less than it was before the collision. What type of collision was this? How can you tell?

20

A plane, flying horizontally, releases a bomb which explodes in the air. Neglecting air resistance, describe how the center of mass of the entire collection of bomb fragments moves in the moments immediately after the explosion.

21

Can an object have its center of mass located outside the physical boundaries of the object? If so, give 2 examples of objects that fit this description.