Linear momentum

What is the SI unit of momentum?

N x s

when a cannon fires a cannonball, the cannon will recoil backward because the

momentum of the cannonball and cannon is conserved

a freight car moves along a frictionless level railroad track at constant speed. the car is open on top. a large load of coal is suddenly dumped on the car. what happens to the velocity of the car?

it decreases.

a child falls sideways off a sled while sledding on frictionless ice. what happens to the velocity of the sled?

it remains the same

A rubber ball and a lump of putty have equal mass. They are thrown with equal speed against a wall. The ball bounces back with nearly the same speed with which it hit. The putty sticks to the wall. Which objects experiences the greater momentum change?

the ball

A sailboat of mass m is moving with a momentum p. How would you represent its kinetic energy in terms of these two equations?

p²/ (2m)

If you pitch a baseball with twice the kinetic energy you gave it in the previous pitch, the magnitude of its momentum is

1.41 times as much

The area under the curve on a Force versus time (F vs. t) graph represents

impulse

Which of the following is an accurate statement?

If an object is acted on by a non-zero net external force, its momentum will not remain constant.

A small car meshes with a large truck in a head-on collision. Which of the following statements concerning the magnitude of the average collision force is correct?

The small car and the truck experience the same average force.

Two equal mass balls (one red and the other blue) are dropped from the same height, and rebound off the floor. The red ball rebounds to a higher position. Which ball is subjected to the greater magnitude of impulse during its collision with the floor?

the red ball

A Ping-Pong ball moving east at a speed of 4 m/s, collides with a stationary bowling ball. The Ping-Pong ball bounces back to the west, and the bowling ball moves very slowly to the east.

Which object experiences the greater magnitude impulse during the collision?

Neither; both experienced the same magnitude impulse.

Two objects collide and bounce off each other. Linear momentum

is definitely conserved

A 3.0-kg object moves to the right at 4.0 m/s. It collides head-on with a 6.0-kg object moving to the left at 2.0 m/s. Which statement is correct?

The total momentum both before and after the collision is zero.

A 100-kg football linebacker moving at 2.0 m/s tackles head-on an 80-kg halfback running

3.0 m/s. Neglecting the effects due to digging in of cleats,

the halfback will drive the linebacker backward.

In an elastic collision, if the momentum is conserved, then which of the following statements is true about kinetic energy?

kinetic energy is also conserved

when is kinetic energy conserved

in elastic collisions

In a game of pool, the white cue ball hits the #5 ball and stops, while the #5 ball moves away with the same velocity as the cue ball had originally. The type of collision is

elastic

When a light beach ball rolling with a speed of 6.0 m/s collides with a heavy exercise ball at rest, the beach ball's speed after the collision will be, approximately,

6.0 m/s

A golf ball traveling 3.0 m/s to the right collides in a head-on collision with a stationary bowling ball in a friction-free environment. If the collision is almost perfectly elastic, the speed of the golf ball immediately after the collision is

slightly less than 3.0 m/s

A rubber ball with a speed of 5.0 m/s collides head-on elastically with an identical ball at rest.

What is the speed of the initially stopped ball after the collision?

5.0 m/s

A very heavy object moving with speed v collides head-on with a very light object at rest. The collision is elastic, and there is no friction. The heavy object barely slows down. What is the speed of the light object after the collision?

nearly 2v

A very light object moving with speed v collides head-on with a very heavy object at rest, in a frictionless environment. The collision is almost perfectly elastic. The speed of the heavy object after the collision is

much less than v

A red ball with a velocity of +3.0 m/s collides head-on with a yellow ball of equal mass moving with a velocity of -2.0 m/s. What is the velocity of the yellow ball after the collision?

+3.0 m/s

A very heavy object moving with velocity v collides head-on with a very light object moving with velocity -v. The collision is elastic, and there is no friction. The heavy object barely slows down. What is the speed of the light object after the collision?

nearly 3v

In an inelastic collision, if the momentum is conserved, then which of the following statements is true about kinetic energy?

kinetic energy is lost

Two objects collide and stick together. Kinetic energy

is definitely not conserved

A 3.0-kg object moves to the right at 4.0 m/s. It collides in a perfectly inelastic collision with a

6.0 kg object moving to the left at 2.0 m/s. What is the total kinetic energy after the collision?

0 J

a small object collides with a larger object and sticks. which object experiences the larger magnitude of momentum change

Both objects experience the same magnitude of momentum change.

In a game of pool, the white cue ball hits the #9 ball and is deflected at a 35° angle to the original line of motion. What is the angle of deflection below the original line of motion for the #9 ball?

55 degrees

Consider two unequal masses, M and m. Which of the following statements is false?

if a uniform rod of mass m were to join the two masses, this would not alter the position of the center of mass of the system without the rod present

Which of the following is a false statement?

The center of mass of an object must lie within the object.

Tightrope walkers walk with a long flexible rod in order to

lower their center of mass

A plane, flying horizontally, releases a bomb, which explodes before hitting the ground.

Neglecting air resistance, the center of mass of the bomb fragments, just after the explosion

moves along a parabolic path

Two cars collide head-on on a level friction-free road. The collision was completely inelastic and both cars quickly came to rest during the collision. What is true about the velocity of this system's center of mass?

it was always zero