Chapter 6 Multiple Choice
Which of the following situations is an example of a visible change in momentum?
A baseball is hit by a bat
Which of the following statements properly relates the variables in the equation Ft = p?
A large constant force acting over a long time interval causes a large change in momentum.
If a force is exerted on an object, which statement is true?
A small force applied over a long time interval can produce a large change in the object's momentum.
Which of the following situations is an example of a significant change in momentum?
A tennis ball is hit into a net.
Which of the following statements about the conservation of momentum is not correct?
Momentum is not conserved for a system of objects in a head-on collision
A lump of clay is thrown at a wall. A rubber ball of identical mass is thrown with the same speed toward the same wall. Which statement is true?
The ball experiences a greater change in momentum than the clay.
A child with a mass of 23 kg rides a bike with a mass of 5.5 kg at a velocity of 4.5 m/s to the south. Compare the momentum of the child with the momentum of the bike.
The child has a greater momentum than the bike
When comparing the momentum of two moving objects, which of the following is correct?
The less massive object will have less momentum if the velocities are the same
Which of the following equations expresses the work-kinetic energy theorem?
Wnet =deltaKE
A cannon recoils from launching a cannonball. The speed of the cannon's recoil is small because the
cannon has far more mass than the cannonball
A 75 kg person walking around a corner bumped into an 80 kg person who was running around the same corner. The momentum of the 80 kg person
decreased
A 20 kg shopping cart moving at a velocity of 0.5 m/s collides with a store wall and stops. The momentum of the shopping cart
decreases
Two billiard balls collide. Identify the type of collision.
elastic
Two objects move separately after colliding, and both the total momentum and total kinetic energy remain constant. Identify the type of collision.
elastic
A cannon fires a cannonball. The speed of the cannonball will be the same as the speed of the recoiling cannon
if the mass of the cannonball equals the mass of the cannon
The momentum change of an object is equal to the
impulse acting on it
After colliding, objects are deformed and lose some kinetic energy. Identify the type of collision.
inelastic
A roller coaster climbs up a hill at 4 m/s and then zips down the hill at 30 m/s. The momentum of the roller coaster
is greater down the hill than up the hill
What are the SI units for momentum?
kg*m/s
Which of the following energy forms is associated with an object in motion?
kinetic energy
The impulse experienced by a body is equivalent to the body's change in
momentum
In a two-body collision,
momentum is always conserved
In a two-body collision, if the kinetic energy of the system is conserved, then which of the following best describes the momentum after the collision?
must also be conserved
Which of the following best describes the momentum of two bodies after a two-body collision if the kinetic energy of the system is conserved?
must also be conserved
If the momentum of an object is tripled, its kinetic energy will change by what factor?
nine
Which of the following equations can be used to directly calculate an object's momentum, p?
p=mv
Two balls of dough collide and stick together. Identify the type of collision.
perfectly inelastic
Two objects stick together and move with a common velocity after colliding. Identify the type of collision.
perfectly inelastic
Which of the following energy forms is associated with an object due to its position?
potential energy
A rubber ball moving at a speed of 5 m/s hit a flat wall and returned to the thrower at 5 m/s. The magnitude of the momentum of the rubber ball
remained the same
A soccer ball collides with another soccer ball at rest. The total momentum of the balls
remains constant
If the sign of work is negative,
the displacement is in the direction opposite the force
Work is done when
the displacement is not zero
Two objects with different masses collide and bounce back after an elastic collision. Before the collision, the two objects were moving at velocities equal in magnitude but opposite in direction. After the collision,
the less massive object had gained momentum.
The change in an object's momentum is equal to
the product of the force applied to the object and the time interval.
The law of conservation of momentum states that
the total momentum of all objects interacting with one another remains constant regardless of the nature of the forces between the objects
Two swimmers relax close together on air mattresses in a pool. One swimmer's mass is 48 kg, and the other's mass is 55 kg. If the swimmers push away from each other,
their momenta are equal but opposite
Two skaters stand facing each other. One skater's mass is 60 kg, and the other's mass is 72 kg. If the skaters push away from each other without spinning,
their momenta are equal but opposite.
The kinetic energy of an object is quadrupled. Its momentum will change by what factor?
two
A billiard ball collides with a second identical ball in an elastic head-on collision. What is the kinetic energy of the system after the collision compared with the kinetic energy before the collision?
unchanged
