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n |
FCI 18*:
An elevator is being lifted up at a
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constant speed.
(Ignore friction and air
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resistance)
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A. |
The upward force
on the elevator
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by the cable is
greater than
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the downward
force of gravity.
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B. |
The amount of
upward force
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on the elevator
by the cable equals
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the downward
force of gravity.
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C. |
The upward force
on the elevator
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by the cable is
less than
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the downward
force of gravity.
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D. |
It
goes up because the cable is being
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shortened,
not because of the force being
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exerted
by the cable on the elevator.
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E. |
The
upward force on the elevator
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by
the cable is greater than the downward force
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due
to the combined effects of air pressure
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and
the force of gravity.
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