In this worksheet, we will practice using the formula for momentum, p = mv, to calculate the momentum of objects and calculate changes in an object's momentum.

**Q3: **

A book falls off the edge of a table. The book accelerates
at 9.8 m/s^{2} for 0.15 s and its momentum after falling for 0.15 s is
0.147 kg⋅m/s. What is the book’s mass in grams?

**Q4: **

A bowling ball is thrown, after which it has a momentum of 24 kg⋅m/s due to its motion. The bowling ball has a mass of 7.5 kg. If the ball was stationary before it was thrown, at what constant velocity does it move after it is thrown?

**Q5: **

What is the mass of an object that moves at a constant velocity of 2.2 m/s if its momentum is 3.3 kg⋅m/s?

**Q6: **

With what constant velocity does an object of mass 5 kg move if its momentum is 10 kg⋅m/s?

**Q7: **

What is the momentum of an object that has a mass of 2 kg and moves at a constant velocity of 3 m/s?

**Q8: **

A cat has a mass of 3 kg. The cat moves 4 m in a straight line in a time of 2 s. What is the momentum of the cat?

**Q9: **

A car of mass 400 kg is moving at a constant speed of 25 m/s when it crashes into a van moving in the opposite direction at a constant speed of 10 m/s. The van has a mass of 700 kg. What is the total momentum of the car and the van? Consider the direction of the car’s motion to be positive.

**Q10: **

A bag of mass 1.5 kg is being carried horizontally at a velocity of 1.2 m/s when it opens and 0.25 kg of its contents spill out vertically. The person holding the bag does not immediately notice what has happened and, for a short time, they continue to move horizontally at the same speed.

What is the horizontal momentum of the bag after it opens and the contents are spilled?

What is the horizontal momentum of the spilled contents?

**Q11: **

A child of mass 30 kg slides down a slide. Near the top of the slide, the child’s velocity is 0.65 m/s, while near the bottom of the slide, the child’s velocity is 1.35 m/s. How much does the child’s momentum change between these two positions?

**Q12: **

A van that has a mass of 750 kg increases its momentum by 18 750 kg⋅m/s when it accelerates at a constant
2.5 m/s^{2}. For how long
does the van accelerate?

**Q13: **

A tennis ball with a mass of 60 g is thrown at a wall, hitting it while moving at a speed of 15 m/s. The ball bounces back from the wall with a speed 10 m/s. What is the magnitude of the tennis ball’s net momentum change due to the collision?

**Q14: **

A snowball rolls down a snowy hillside, and as more snow sticks to the snowball, it increases in mass. The graph shows how the snowball’s mass and velocity change.

How much does the momentum of the snowball increase from when its velocity is 5 m/s to when its velocity is 10 m/s?

By how much would the momentum of the snowball have increased when its velocity changed from 5 m/s to 10 m/s if no snow stuck to it as it rolled?

**Q15: **

The graph shows the change in momentum of an object as its velocity changes. What is the mass of the object?

**Q16: **

A swimmer with a mass of 50 kg swims in the sea directly away from the shore at 0.25 m/s. A wave heads directly toward the shore at 1.25 m/s. A part of the wave that has a mass of 12 kg hits the swimmer. What is the total momentum of the swimmer and the part of the wave that hits her? Consider the direction of the swimmer’s motion to be positive.

**Q17: **

The moving golf ball shown in the diagram hits the golf club and comes to rest. What is the change in the ball’s momentum? Take the direction that the ball moves in as the positive direction.