Physicsmedium · Past Paper
A weightlifter is holding a 100 kg barbell over his head for 5 seconds. The work done by the weightlifter on the barbell is:
A500 J
B4900 J
C0 J
D980 J
✓ Correct Answer: C — 0 J
Since there is no vertical displacement of the barbell while holding it, the work done is zero.
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