An elevator is being lifted upward at a constant speed by a steel cable. All frictional forces are neglected. In this situation, forces on the elevator are such that
A. the upward force by the cable is equal to the downward force of gravity.
B. the upward force by the cable is smaller than the downward force of gravity.
C. the upward force by the cable is greater than the downward force of gravity.
D. None of these choices are correct (the elevator goes up because the cable is being shortened, not because an upward force is exerted on the elevator by the cable)
Answer: A
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