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Chapter 9
The cart’s change of momentum is
1. –30 kg m/s.
2. –20 kg m/s.
3. –10 kg m/s.
4. 10 kg m/s.
5. 30 kg m/s.
The cart’s change of momentum is
1. –30 kg m/s.
2. –20 kg m/s.
3. –10 kg m/s.
4. 10 kg m/s.
5. 30 kg m/s.
A 10 g rubber ball and a 10 g clay ball are thrown
at a wall with equal speeds. The rubber ball
bounces, the clay ball sticks. Which ball exerts a
larger impulse on the wall?
1. The clay ball exerts a larger impulse because
it sticks.
2. The rubber ball exerts a larger impulse
because it bounces.
3. They exert equal impulses because they have
equal momenta.
4. Neither exerts an impulse on the wall because
the wall doesn’t move.
A 10 g rubber ball and a 10 g clay ball are thrown
at a wall with equal speeds. The rubber ball
bounces, the clay ball sticks. Which ball exerts a
larger impulse on the wall?
1. The clay ball exerts a larger impulse because
it sticks.
2. The rubber ball exerts a larger impulse
because it bounces.
3. They exert equal impulses because they have
equal momenta.
4. Neither exerts an impulse on the wall because
the wall doesn’t move.
Objects A and C are made of different materials, with
different “springiness,” but they have the same mass and
are initially at rest. When ball B collides with object A, the
ball ends up at rest. When ball B is thrown with the same
speed and collides with object C, the ball rebounds to the
left. Compare the velocities of A and C after the collisions.
Is vA greater than, equal to, or less than vC?
1. vA > vC
2. vA = vC
3. vA < vC
Objects A and C are made of different materials, with
different “springiness,” but they have the same mass and
are initially at rest. When ball B collides with object A, the
ball ends up at rest. When ball B is thrown with the same
speed and collides with object C, the ball rebounds to the
left. Compare the velocities of A and C after the collisions.
Is vA greater than, equal to, or less than vC?
1. vA > vC
2. vA = vC
3. vA < vC
An explosion in a rigid pipe shoots out three
pieces. A 6 g piece comes out the right end. A 4 g
piece comes out the left end with twice the speed
of the 6 g piece. From which end does the third
piece emerge?
1. Left end
2. Right end
An explosion in a rigid pipe shoots out three
pieces. A 6 g piece comes out the right end. A 4 g
piece comes out the left end with twice the speed
of the 6 g piece. From which end does the third
piece emerge?
1. Left end
2. Right end
The two particles are both moving to the right. Particle 1
catches up with particle 2 and collides with it. The
particles stick together and continue on with velocity vf.
Which of these statements is true?
1.
2.
3.
4.
5.
vf is greater than v1.
vf = v1 .
vf is less than v2.
vf = v2 .
vf is greater than v2, but less than v1.
The two particles are both moving to the right. Particle 1
catches up with particle 2 and collides with it. The
particles stick together and continue on with velocity vf.
Which of these statements is true?
1.
2.
3.
4.
5.
vf is greater than v1.
vf = v1 .
vf is less than v2.
vf = v2 .
vf is greater than v2, but less than v1.
A dry ice (solid carbon dioxide) puck revolves in a circle on
the end of a lightweight rigid rod that turns on frictionless
bearings. A cushion of CO2 gas allows the puck to glide
across the surface without friction. As the puck sublimates
(changes from a solid to a gas), its speed
1. increases.
2. decreases.
3. stays the same.
A dry ice (solid carbon dioxide) puck revolves in a circle on
the end of a lightweight rigid rod that turns on frictionless
bearings. A cushion of CO2 gas allows the puck to glide
across the surface without friction. As the puck sublimates
(changes from a solid to a gas), its speed
1. increases.
2. decreases.
3. stays the same.
Chapter 9
Reading Quiz
Impulse is
1. a force that is applied at a random time.
2. a force that is applied very suddenly.
3. the area under the force curve in a
force-versus-time graph.
4. the time interval that a force lasts.
Impulse is
1. a force that is applied at a random time.
2. a force that is applied very suddenly.
3. the area under the force curve in a
force-versus-time graph.
4. the time interval that a force lasts.
The total momentum of a system is conserved
1.
2.
3.
4.
always.
if the system is isolated.
if the forces are conservative.
never; it’s just an approximation.
The total momentum of a system is conserved
1.
2.
3.
4.
always.
if the system is isolated.
if the forces are conservative.
never; it’s just an approximation.
In an inelastic collision,
1.
2.
3.
4.
5.
impulse is conserved.
momentum is conserved.
force is conserved.
energy is conserved.
elasticity is conserved.
In an inelastic collision,
1.
2.
3.
4.
5.
impulse is conserved.
momentum is conserved.
force is conserved.
energy is conserved.
elasticity is conserved.