Momentum and Collisions | U7 Test Prep

Momentum

100

What two quantities must you have to determine momentum?

Mass and Velocity

200

A cannon fires a cannonball. Describe what happens to the cannon.

The cannon will move backwards with the same momentum the cannonball has moving forward.

300

Object 1 moves with a speed of 32 m/s and Object 2 moves with a speed of 22 m/s. Which object has more momentum?

Neither, you need to know the mass of both objects to determine momentum.

400

Find the velocity of a 32 kg object with a momentum of 116 kgm/s.

3.63 m/s

500

What velocity must a 1540 kg car have in order to have the same momentum as a 2370 kg truck witha velocity of 15 m/s to the east?

V = 23.1 m/s

Impulse and Change in Momentum

100

What is change in momentum equal to?

Impulse

200

Show how the impulse acting on an object is equal to the change in momentum that object experiences (i.e. show the formula that equates the two).

Ft = m(delta v)

300

Explain why an egg landing on a plate will break, but an egg landing on a pillow stays intact.

The egg breaks on a plate because it has a large force acting over a small time. This causes a very small change in momentum, which means the egg is harder to stop (more momentum with the egg hits the ground). The egg doesn't break on a pillow because it has a large force acting over a larger amount of time. This causes a large change in momentum, which means the egg is easier to stop (less momentum when the egg hits the ground).

400

A rubber ball with a mass of .48 kg is dropped onto a steel plate. The ball's velocity just before impact is 3.8 m/s and just after impact is 3.4 m/s. What is the change in the ball's momentum?

-0.19 kg*m/s

500

A football punter accelerates a .55 kg football from rest to a speed of 8.0 m/s in .25 s. What constant force does the punter exert on the ball?

F = 18 N

Conservation of Momentum

100

State the law of conservation of momentum.

The total momentum for a system must be maintained or conserved. Momentum can be transferred, but cannot be gained or lost.

200

Consider a perfectly inelastic collision between two cars of equal size traveling at the same speed. Which vehicle has a greater change in kinetic energy as a result of the collision?

They have the same change in kinetic energy

300

Explain how a launching rocket conserves momentum if it starts from rest.

The rocket moves up with a positive momentum and the fuel/explosion moves down with an equal but negative momentum. They cancel each other out and equal zero which is the momentum the rocket started with.

400

If two objects collide and one is initially at rest, is it possible for both to be at rest after the collision? Is it possible for one object to be at rest after the collision? Explain.

They cannot both be at rest because of the conservation of momentum. One can be at rest if the first object transfers all of its momentum to the second object.

500

An initially at rest cannonball is launched from an initially at rest cannon with a momentum of 1750 kg * m/s. Calculate the recoil velocity of the cannon if it has a mass of 2650 kg. 

-0.660 m/s

Collisions

100

Is kinetic energy conserved in elastic collisions?

For the collision as whole = yes

200

What happens to both objects in a perfectly inelastic collision?

The combine and stay together after the collision.

300

An 88 kg fullback moving east with a speed of 5.0 m/s is tackled by a 97 kg opponent running west at 3.0 m/s, and the collision is perfectly inelastic. Calculate the velocity of the players just after the tackle. 

V = .81 m/s

400

A student hits a .4 kg white billiard ball giving it an initial speed of 5 m/s. It hits a blue billiard ball with the same mass initially at rest. Afterwards, the blue billiard ball is traveling 5 m/s. What is the final speed of the white billiard ball?

0 m/s; it is at rest.

500

A bowling ball with a mass of 4 kg strikes a pin with a mass of 1.8 kg. The pin flies forward with a velocity of 4 m/s, and the ball continues forward at 3 m/s. What was the original velocity of the ball?

4.8 m/s

Gnann Fun Questions of Randomness

100

Can you come up with 5 palindromes in 30 seconds or less? If you can, you'll get the points. If you can't, another team will.

Whatcha got?

200

ChatGPT is going to flip a coin for us... you guess the same thing as ChatGPT, you get the points. Wrong and they get randomly assigned to someone else!

Let's go to ChatGPT

300

Higher or Lower... if you ask ChatGPT "How much wood would a woodchuck chuck if a woodchuck could chuck wood?"

Would the answer be higher or lower than 500 pounds of wood?

Correct = your points; incorrect = randomly another teams

Higher; 700 pounds!

400

Higher or lower... Was the mean retail price of a microwave oven higher or lower than $400 in 1980. Guess correct, you get the points. Guess incorrect, so sorry... your points will randomly be assigned to someone else. 

Higher; $425.

500

I have chosen a random number... either 1 or 2. Guess the number correctly and you get the points. Guess incorrectly, and the points get randomly assigned to one of the two other teams. 

1