A construction crane lowers a beam into place at constant speed. Consider the work Wg done by gravity on the beam and the work W
1 answer:
Answer:
Wg is positive and WT negative.
(Letters in options are all wrongly written).
Explanation:
Remember that the work of a force is the internal product between the force and the displacement .
Since the displacement is downwards like the weight, the work done by gravity is positive, while the work done by the tension is negative since it points upwards.
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