Impulse and Momentum 222

During a car accident, a 125 kg driver is moving at 31 m/s and in 1.5 seconds is brought to rest by an inflating air bag. What is the magnitude of the change in momentum of the driver? 4.0 kg • 21 kg • 47 kg • 3900 kg •

3900 kg • m/s

A boy and his skateboard have a combined mass of 65 kg. What is the speed of the boy and skateboard if they have a momentum of 275 kg • ? 0 m/s 0.24 m/s 4.2 m/s 8.5 m/s

4.2 m/s

A 57 g tennis ball is traveling at 45 m/s to the right, when it hits a racket. The ball reverses direction and travels at 33 m/s. The ball is in contact with the racket for 0.0085 s. What is the magnitude of the force that was exerted on the ball? 1.8 N 12 N 81 N 520 N

520 N

A 0.060 kg ball hits the ground with a speed of -32 m/s. The ball is in contact with the ground for 45 milliseconds and the ground exerts a +55 N force on the ball. What is the magnitude of the velocity after it hits the ground? 9.3 m/s 12 m/s 41 m/s 73 m/s

9.3 m/s

A car's momentum is p when it is traveling with a velocity of v. If the velocity of that car doubles, what is the new momentum of the car? p p 2p 4p

2p

What are possible formulas for impulse? Check all that apply. J = Ft J = J = Fv J = J = mv J = p

J= Ftrianglet J=mtrainglev J=trainglep

An object with a mass of 1.5 kg changes its velocity from +15 m/s to +22 m/s during a time interval of 3.5 seconds. What impulse was delivered to the object? 3.0 N • s 11 N • s 25 N • s 56 N • s

11 N • s

A baseball has a mass of 0.45 kg and is thrown with a speed of 25 m/s. What is the momentum of the baseball? 0.018 kg • 11 kg • 56 kg • 140 kg •

11 kg • m/s

In a lab, four balls have the same velocities but different masses. If the mass of ball B triples, its new momentum is kg • .m/s

13 kg • m/s .

A 0.25 kg baseball is in contact with a bat for 0.0075 s and exerts a force of 18,500 N. What impulse is delivered to the ball? 33 kg • 140 kg • 4600 kg • 74,000 kg •

140 kg • m/s

Different forces were applied to five balls, and each force was applied for the same amount of time. The data is in the table. If the force on ball A doubles while the time remains the same, what happens to the impulse? It divides in half. It does not change. It doubles. It quadruples.

It doubles.

Students perform an experiment in which they drop two eggs with equal mass from a balcony. In the first trial, the egg hits the ground and breaks. In the second trial, the egg hits a foam cushion and does not break or bounce. What conclusions about impulse can the students make? The impulse was greater in the first experiment because the egg broke. The impulse was greater in the second experiment because the egg did not break. The impulse was the same in both experiments because the egg came to a stop. The impulse cannot be determined without the mass and velocity of the eggs.

The impulse was the same in both experiments because the egg came to a stop.

A student performs a lab measuring the velocities of toy cars of different masses. Which cars have the same magnitude of momentum? Check all that apply. car 1 car 2 car 3 car 4 car 5

car 1 car 2

Four identical lab carts each have a mass of 200 kg. Different masses are added to the carts and the velocities are measured. All carts move to the right. Which cart has the greatest momentum? cart A cart B cart C cart D

cart A

What type of relationship exists between momentum and mass? direct inverse logarithmic quadratic

direct

What is the SI unit for momentum? kg • m kg • kg • kg •

kg • m/s

What are possible units for impulse? Check all that apply. kg • m kg • N • s N • m

kg • m/s N • s

Which formulas show the relationships between momentum, mass, and velocity? Check all that apply. p = mv p = p = m = p = v = v =

p=mv m=p/v v=p/m

What best describes an impulse acting on an object? the net force on an object divided by the time of impact the velocity of an object divided by its mass the product of an object's mass and the time of force impact the product of an object's mass and its change in velocity

the product of an object's mass and its change in velocity

Students are completing a lab in which they let a lab cart roll down a ramp. The students record the mass of the cart, the height of the ramp, and the velocity at the bottom of the ramp. The students then calculate the momentum of the cart at the bottom of the ramp. Which trial's cart has the greatest momentum at the bottom of the ramp? trial 1, because this trial has the greatest velocity trial 2, because this trial has the greatest ramp height trial 3, because this trial has a large mass and a large velocity trial 4, because this trial has the greatest mass

trial 3, because this trial has a large mass and a large velocity