Lesson 4.5

Use the picture to identify the mass and velocity of both objects. Then match the information below with correct descriptions.

• Momentum of the larger ball before collision

• Momentum of the smaller ball before collision

• Total momentum before collision

Answer explanation

This question links to success criteria: I can determine the individual and total momenta values before and after a collision.

If you got it correct place a check mark in the question results section. If you got it incorrect place an X in that section. If this was a redemption question, cross out the one X and replace it with a check mark.

Isaac is working on his momentum lab. He has calculated that the total momentum in his system is 0.15 kg⋅m/s after the collision. If the second ball was not moving before the collision what was the momentum of the first ball before the collision?

• 0.15 kg⋅m/s

• - 0.30 kg⋅m/s

• 0.85 kg⋅m/s

• 0.00 kg⋅m/s

Answer explanation

This question links to success criteria: I can determine the individual and total momenta values before and after a collision.

If you got it correct place a check mark in the question results section. If you got it incorrect place an X in that section. If this was a redemption question, cross out the one X and replace it with a check mark.

A 10-kg toy truck moves at 5 m/s East. It collides head-on with a 5-kg toy car moving 10 m/s moving West. What is the total momentum of the system?

• 0 kg·m/s

• 30 kg·m/s

• 50 kg·m/s 

•  10 kg·m/s

Answer explanation

This question links to success criteria: I can determine the individual and total momenta values before and after a collision.

If you got it correct place a check mark in the question results section. If you got it incorrect place an X in that section. If this was a redemption question, cross out the one X and replace it with a check mark.

Two skaters begin at rest. Skater 1 has a smaller mass than Skater 2. After they push off each other,...

• Skater 1 experiences a greater change in momentum

• Skater 2 experiences a greater change in momentum

• Skater 1 has a greater velocity than Skater 2

• Skater 1 experiences a greater force

Answer explanation

This question links to success criteria: I can use conservation of momentum to predict the outcomes of various types of collisions.

If you got it correct place a check mark in the question results section. If you got it incorrect place an X in that section. If this was a redemption question, cross out the one X and replace it with a check mark.

A person on a stationary skateboard throws a bowling ball with a velocity of -5.0 m/s. What is a possible speed of the person after the throw? 

• 0 m/s

• 1.5 m/s

• 5.0  m/s

• 7.5 m/s

Answer explanation

This question links to success criteria: I can use conservation of momentum to predict the outcomes of various types of collisions.

If you got it correct place a check mark in the question results section. If you got it incorrect place an X in that section. If this was a redemption question, cross out the one X and replace it with a check mark.

Two equal mass bowling balls are thrown at 5 m/s towards stationary pins. If one pin has 1kg of mass and the other has 3kg of mass, which pin will move faster after it gets hit?

• The 3kg pin will move faster.

• Both pins will move at 5 m/s.

• The bowling ball will always miss the pins.

• The 1 kg pin will move faster.

Answer explanation

This question links to success criteria: I can use conservation of momentum to predict the outcomes of various types of collisions.

If you got it correct place a check mark in the question results section. If you got it incorrect place an X in that section. If this was a redemption question, cross out the one X and replace it with a check mark.

Two people are running towards each other. Person A has a mass of 75 kg and runs at 2 m/s. Person B has a mass of 125 kg and runs at -1.5 m/s.   Which of the following best describes their motion after they collide.

• They do cancel each other out and stop moving.

• They do cancel each other out and both bounce off, reversing direction

• They don't cancel each other out and move in the negative direction.

• They don't cancel each other out and move in the positive direction

Answer explanation

This question links to success criteria: I can use conservation of momentum to predict the outcomes of various types of collisions.

If you got it correct place a check mark in the question results section. If you got it incorrect place an X in that section. If this was a redemption question, cross out the one X and replace it with a check mark.

Tycho's lab group found that the marbles after the collision had less momentum than expected. Which of the following best explains why momentum did not appear to be conserved?

• The marbles experienced friction from the table and the rulers.

• Tycho didn't record the video in slow motion.

• The marbles had different masses.

• Tycho collected his data on a hot day.

Answer explanation

This question links to success criteria: I can identify conditions that mean momentum is not conserved.

If you got it correct place a check mark in the question results section. If you got it incorrect place an X in that section. If this was a redemption question, cross out the one X and replace it with a check mark.

The pole in the picture has a mass of 380kg while the car has a mass of 950kg. The pole is able to bring the car to a stop without being moved. Why did momentum not appear to be conserved?

• The pole is narrower and was able to apply its force only to the front of the car.

• The pole is attached to the earth, the mass of the earth needs to be considered.

• The front of the car crumbled reducing the force of impact. This lower force couldn't move the pole.

• Momentum does not get conserved in car crashes.

Answer explanation

This question links to success criteria: I can identify conditions that mean momentum is not conserved.

If you got it correct place a check mark in the question results section. If you got it incorrect place an X in that section. If this was a redemption question, cross out the one X and replace it with a check mark.

In which situation(s) might it appear that momentum is not conserved?

• When both objects were moving before the collision

• When the event does not occur in a "closed system."

• When the objects are moving in ellipses

• When the objects colliding are tectonic plates.

Answer explanation

This question links to success criteria: I can identify conditions that mean momentum is not conserved.

If you got it correct place a check mark in the question results section. If you got it incorrect place an X in that section. If this was a redemption question, cross out the one X and replace it with a check mark.