CH 6 & 7 Review - Energy and Momentum

The speed of a 4-kg ball with a momentum of 12 kg m/s is

• 3 m/s

• 4 m/s

• 12 m/s

• 48 m/s

A large heavy truck and a small baby carriage roll down a hill. Neglecting friction, at the bottom of the hill, the baby carriage will likely have

• less momentum

• about the same momentum

• more momentum

) It is correct to say that impulse is equal to

• momentum

• a corresponding change in momentum

• force multiplied by the distance it acts

• velocity multiplied by time

A car traveling along the highway brakes to a stop over a certain distance. More braking force is required if the car has

• more mass

• more momentum

• less stopping distance

• all of these

Compared with falling on a stone floor, a wine glass may not break when it falls on a carpeted floor because the

• carpeted floor provides a smaller impulse

• stopping time is shorter on the carpet

• stopping time is longer on the carpet

• carpet provides a smaller impulse and a longer time

A karate expert executes a swift blow and breaks a cement block with her bare hand. The magnitude of the force on her hand is

• zero

• less than the force applied to the cement block

• the same as the force applied to the block

• more than the force applied to the block

You're driving down the highway and a bug spatters into your windshield. Which undergoes the greater change in momentum during the time of contact?

• the bug

• your car

• both the same

Two billiard balls having the same mass and speed roll toward each other. What is their combined momentum after they meet?

• zero

• half the sum of their original momentums

• twice the sum of their original momentums

• need more information

Two identical freight cars roll without friction (one at 1 m/s, the other at 2 m/s) toward each other on a level track. They collide, couple together, and roll away in the direction of

• the slower car

• the faster car

• neither, for they stop

The work you do when pushing a shopping cart a given distance while applying twice as much force is

• half as much

• twice as much

• four times as much

• the same amount