A 500-kg elevator is pulled upward by a cable that exerts a constant force of 5500 N on the elevator for a distance of 50.0 m. The elevator is the system
(a) What is the work done by the 5500-N force? (b) What is the work done by the gravitational force? (c) What is the net work done on the elevator?
(a) 275 Kj (b) -245 kJ (c) 30.0 kJ
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A. 10% B. 20% C. 50% D. 80% E. 99%
Two uniform solid spheres have the same mass, but one has twice the radius of the other. The ratio of the larger sphere's moment of inertia to that of the smaller sphere is
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Adding a few impurity atoms, like arsenic or gallium, to a semiconductor can produce
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