A man holds a heavy suitcase stationary in his hand for 5 minutes. The WORK done by him on the suitcase is:
AF × 5 minutes, computed as force times time
BZero, because the displacement of the suitcase is zero
CNegative, since holding requires constant effort
DEqual to weight × height of suitcase from ground
Answer & Solution
Correct answer: B. Zero, because the displacement of the suitcase is zero
Work done is zero because displacement is zero. Even though the man is exerting a force (upward, against gravity) and gets tired, in physics no displacement means no work.
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