Momentum & Impulse

The law of conservation of momentum states that, 

• p before is less than p after
• p before is the same as p after
• p before is more than p after

A 0.250 kg cart moving at 0.400 m/s has how much momentum?

• 0.1 kg-m/s
• 1 kg-m/s
• 10 kg-m/s
• 100 kg-m/s

If 2 objects collide and stick together, what will happen to their velocities?

• velocities will increase
• velocities will decrease
• velocities will stay the same
• none of the above

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

• 0 kgm/s
• 30 kgm/s
• 50 kgm/s
• 10 kgm/s

A biker with a mass of 75 kg moves along the path with a constant velocity of 5 m/s. What is the biker's momentum?

• 25 m/s
• 375 m/s
• 25 kg m/s
• 375 kg m/s

When the speed of an object is doubled, its momentum

• remains unchanged in accord with the conservation of momentum.
• doubles
• quadruples
• decreases

In this type of collision, objects tend to "stick" together.

• elastic
• inelastic 
• They "stick" together in both types of collisions

The difference between a car hitting a wall vs. a car hitting a hay stack is

• the Impulse on the car hitting the wall is greater
• the change in momentum of the car hitting the wall is greater
• the force on the car hitting the hay stack is greater
• the collision time of the car hitting the hay stack is greater

Softer landings tend to

• increase impact force
• increase force
• increase collision time
• increase change in momentum

The graph shows the force on an object of mass M as a function of time. For the time interval 0 to 4 s, the total change in the momentum of the object is

• 40 kg m/s 
• 20 kg m/s
• 0 kg m/s 
• – 20 kg m/s