Physics Quiz

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Physics Quiz MOMENTUM Each question is multiple
choice. Select the best response to the question
by pressing the button to the left of your
choice. If your answer is correct, you will hear
an applause. Use the forward and backward
buttons at the lower corners of the slides to
advance questions.
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1. What type of quantity is momentum?
A. scalar
B. tensor
C. matrix
D. vector
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2. What are the SI units for momentum?
A. kg.m/s
B. kg.m/s2
C. kg.m
D. N.s2
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3. Which equation below correctly computes
momentum?
A.
B.
C.
D.
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4. The net change in an objects momentum is
called _______ .
A. work
B. impulse
C. force
D. torque
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5. What is the magnitude of an objects momentum
if the objects mass is 5.0 kg and its speed is
6.0 m/s?
A. 90 kgm/s
B. 180 kgm/s
C. 15 kgm/s
D. 30 kgm/s
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6. If an objects initial momentum is 20 kgm/s
and its final momentum after 2 seconds is -20
kgm/s, what average force acted upon it?
A. -20 N
B. 20 N
C. 10 N
D. -80 N
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7. Impulse may be understood as __________ .
A. the slope of the tangent to the graph of Force
vs Time at any time t.
B. the area under a Force vs Velocity graph.
C. the area under a Momentum vs Time graph.
D. the area under a Force vs Time graph.
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8. When is the momentum of a single object
conserved?
A. Momentum is always conserved.
B. Momentum is conserved when the net force
acting on the object is zero.
C. Momentum can only be conserved if the object
is interacting with another object.
D. The momentum of a single object can never be
conserved.
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9. When is the total momentum of a system of
interacting objects conserved?
A. The total momentum of a system is conserved
when the net external force acting on the system
is zero.
B. The total momentum of a system is conserved
when the internal forces add up to zero.
C. The total momentum is conserved when there are
no internal forces.
D. The total momentum of a system can not be
conserved it the objects are interacting.
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10. Suppose objects A and B are interacting and
due to this interaction object A experience a
change in momentum of Dp. What is the change in
momentum experienced by object B?
A. Dp
B. 2Dp
C. -Dp
D. -2Dp
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11. While driving 60 mph on the highway a bug
flying in the opposite direction splats on the
windshield right in front of you. Which
experienced the greater change in momentum, your
car or the bug?
A. Both the same but in opposite directions.
B. The bug because of its smaller mass.
C. The bug because of its greater change in
velocity.
D. The bug because it changed directions.
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12. A collision involving objects that stick
together is called ______ .
A. an elastic collision
B. a perfectly inelastic collision
C. a partially elastic collision
D. a head-on collision
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13. What is an elastic collision?
A. An elastic collision conserves kinetic energy.
B. In an elastic collision the objects stick
together.
C. In an elastic collision momentum is not
conserved.
D. In an elastic collision the colliding masses
exchange velocities.
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15. What factors cause injury during a car crash?

1. short stopping distance 2. short stopping time
3. large area of contact 4. staying in your seat
A. 1 and 3 above
B. 2 and 4 above
C. 2 and 3 above
D. 1 and 2 above
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15. What is true about the conservation of
momentum during a collision that takes place in
two dimensions?
A. The change in momentum in the x-direction is
equal and opposite to the change in momentum in
the y-direction.
B. Momenta in the x-direction and in the
y-direction are both conserved independently.
C. The change in momentum in the x-direction is
equal to the change in momentum in the
y-direction.
D. The initial momentum in the x-direction must
be equal to the final momentum in the y-direction.
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16. Suppose you are stranded on a frozen lake
where the ice is too slippery to walk. All you
have is a bag of gold coins. How can you get off
the ice before freezing to death?
A. Lay the gold coins on the ice and hope the sun
heats them enough to melt the ice. (Do you
foresee a problem doing this?)
B. Use a coin as a signal mirror to attract
attention. (Hope its not cloudy.)
C. Throw the coins in the direction opposite from
which you wish to slide. Conservation of momentum
will do the rest.
D. Give up, count your money, and die.
This is the last question of this quiz.