Roots 2

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B. 1 kg·m/s.

A 1-kg chunk of putty moving at 1 m/ s collides and sticks to a 5-kg bowling ball initially at rest. The bowling ball and putty then move with a momentum of a. 0 kg·m/s. b. 1 kg·m/s. c. 2 kg·m/s. d. 5 kg·m/s. e. more than 5 kg∙m/s.

B. 5.0 m/s

A 4.0 kg ball has a momentum of 20.0 kg m/s. What is the ball's speed? A. 0.2 m/s B. 5.0 m/s C. 20.0 m/s

D. all of these

The force on an apple hitting the ground depends upon a. the speed of the apple just before it hits. b. the time of impact with the ground. c. whether or not the apple bounces. d. all of these

D. exhaust gases.

The force that accelerates a rocket in outer space is exerted on the rocket by the a. rocket's engine. b. rocket's wings. c. atmospheric pressure. d. exhaust gases. e. none of these

impulse acting on it

The momentum change of an object is equal to the

a pickup truck traveling down the highway

which of the following has the largest momentum?

B. 4.0 kg

A ball is moving at 6.0 m/s and has a momentum of 24.0 kg m/s. What is the ball's mass? A. 0.3 kg B. 4.0 kg C. 24.0 kg

if the mass of the cannonball equals the mass of the cannon

A cannon fires a cannonball. the speed of the cannon ball will be the same as the speed of the recoiling cannon

C) momentum.

A heavy truck and a small truck roll down a hill. Neglecting friction, at the bottom of the hill, the heavy truck will have greater A) speed. B) acceleration. C) momentum. D) all of these. E) none of these.

C) identical to the force applied to the block.

A karate expert executes a swift blow and breaks a cement block with her bare hand. The magnitude of the force experienced by her hand is A) zero. B) less than the force applied to the cement block. C) identical to the force applied to the block. D) more than the force applied to the block. E) impossible to predict without additional information.

D. all of these

A karate expert executes a swift blow and splits a cement block with her bare hand. The force on both the block and the expert have the same magnitude, a. impulse on both the block and the expert's hand. b. force on both the block and the expert's hand. c. time of impact on both the block and the expert's hand. d. all of these e. none of these

C. Momentum

A moving object on which no forces are acting will continue to move with constant a. acceleration. b. impulse. c. momentum. d. all of these e. none of these

A. twice as much momentum.

Compared to a sports car moving at 30 miles per hour, the same sports car moving at 60 miles per hour has A. twice as much momentum. B. four times as much momentum. C. the same momentum.

C) may be less and may be more.

Compared to the force that brings a small car to a stop, the force required to bring a heavy truck traveling at the same speed to a stop A) is less. B) is more. C) may be less and may be more.

increase the force acting on it, follow through when hitting the ball, increase the time of contact with the ball, swing as hard as possible

In order to increase the final momentum of a golf ball we could

A. zero.

Recoil is noticeable if we throw a heavy ball while standing on roller skates. If instead we go through the motions of throwing the ball but hold onto it, our net recoil will be a. zero. b. the same as before. c. small, but noticeable.

D. throw something in the direction opposite to the way she wants to go.

Suppose a girl is standing on a pond where there is no friction between her feet and the ice. In order to get off the ice, she can A. bend over touching the ice in front of her and then bring her feet to her hands. B. walk very slowly on tiptoe. C. get on her hands and knees and crawl off the ice D. throw something in the direction opposite to the way she wants to go. E. all of the above will work

A. the target would be a safer place that where the cannon operator is located

Suppose a gun were made of a strong but very light material. Suppose also that the pellet is more massive than the gun itself. For such a weapon a. the target would be safer than the shooter. b. recoil problems would be lessened. c. conservation of energy would not hold. d. conservation of momentum would not hold. e. both conservation of energy and momentum would not hold.

B. astronaut will never catch the first bounce.

Suppose an astronaut in outer space wishes to play a solitary "throw, bounce, and catch" game by tossing a ball against a very massive and perfectly elastic concrete wall. If the ball is as massive as the astronaut, the a. astronaut will catch one bounce only. b. astronaut will never catch the first bounce. c. astronaut's time between catches will decrease as the game progresses. d. none of these

C. about 10 times

When you jump from an elevated position you usually bend your knees upon reaching the ground. By doing this, the time of the impact is about 10 times more than for a stiff-legged landing. In this way the average force your body experiences is reduced by a. less than 10 times. b. more than 10 times. c. about 10 times.

C. The large truck

Which has more momentum, a large truck moving at 30 miles per hour or a small truck moving at 30 miles per hour? A. Both have the same momentum. B. The small truck C. The large truck

A. mass times its velocity.

The momentum of an object is defined as the object's A. mass times its velocity. B. force times the time interval. C. force times its acceleration. D. mass times its acceleration.

C. cannon has more mass than the ball

A cannon recoils from firing a cannonball. The speed of the cannon's recoil is small because the a. force against the cannon is smaller than against the ball. b. momentum is mainly concentrated in the ball. c. cannon has more mass than the ball. d. momentum of the cannon is smaller.

B. impulse.

A cannonball shot from a long-barrel cannon travels faster than one shot from a short-barrel cannon because the cannonball receives a greater A. force. B. impulse. C. both A and B D. neither A nor B

D. all of these

A car traveling along the highway needs a certain amount of force exerted on it to stop. More stopping force may be required when the car has a. more mass. b. more momentum. c. less stopping distance. d. all of these e. none of these

E) all of the above

A collision is considered elastic if _____________. a)there is no lasting deformation b) after the collision, the objects have the same shape as before the collision c) the objects that collide don't get hot d) there is no sound generated during the collision e) all of the above

A. doubled

A freight train rolls along a track with considerable momentum. If it were to roll at the same speed but had twice as much mass its momentum, would be A. doubled. B. unchanged. C. zero. D. quadrupled.

A. greater.

A heavy truck and a small car rolling down a hill at the same speed are forced to stop in the same amount of time compared to the force that stops the car, the force needed to stop the truck is a. greater. b. smaller. c. the same.

B. The rubber ball will produce a greater impulse because it will bounce.

A piece of putty and a rubber ball have the same mass. If you drop them from the same height, which object will produce greater and why? A. The silly putty will produce greater impulse because it will bounce. B. The rubber ball will produce a greater impulse because it will bounce. C. The silly putty will produce greater impulse because it will stop when it hits the ground.

C. 1 unit.

A piece of putty moving with I unit of momentum strikes and sticks to a heavy bowling ball that is initially at rest. After the putty sticks to the ball, both move with a combined momentum of a. less than 1 unit. b. more than 1 unit. c. 1 unit. d. not enough information

D) impossible to determine without additional information

Compared to the force that brings a small car to a stop, the force required to bring a heavy truck to a stop A) is less. B) is more. C) is the same. D) impossible to determine without additional information

it is accelerating(or decelerating) there for is a force acting on it, its velocity is changing

If the momentum of an object changes and its mass remains constant

C. time of impact is increased

In order to catch a ball, a baseball player extends the hand forward before impact with the ball and then lets it ride backward in the direction of the ball's motion upon impact. doing this reduces the force of impact on the players hand principally because the a. force of impact is reduced. b. relative velocity is less. c. time of impact is increased. d. time of impact is decreased. e. none of these

there are no forces acting on the system

Momentum of a system is conserved only when

B. time the force acts

The difference between impulse and impact force involves the a. distance the force acts. b. time the force acts. c. difference between acceleration and velocity. d. mass and its effect on resisting a change in momentum.

B. increase the time of impact in a collision.

The reason padded dashboards are used in cars is that they A. decrease the momentum of a collision. B. increase the time of impact in a collision. C. look nice and feel good. D. decrease the impulse in a collision.

A) 0

Two billiard balls having the same mass and speed, roll toward each other. What is their combined momentum after they meet ? A) 0 B) half the sum of their original momentums. C) twice the sum of their original momentums D) impossible to determine without additional information

A) 0 kg m/s.

Two billiard balls having the same mass roll toward each other, each moving at the same speed. What is the combined momentum of the two balls? A) 0 kg m/s. B) 10 kg m/s. C) more information need to determine.

C. Momentum

Two objects, A and B have the same size and shape, but A is twice as heavy as B. When they are dropped simultaneously from a tower, they reach the ground at the same time, but A has greater a. speed. b. acceleration. c. momentum. d. all of these e. none of these


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