Physicshard · Past Paper
A girl of mass 40 kg runs up a flight of 50 steps, each 10 cm high. The work done by her is: (g = 10 m/s^2)
A2000 J
B200 J
C20000 J
D20 J
✓ Correct Answer: A — 2000 J
Total height = 50 * 0.1 m = 5 m. Work = mgh = 40 * 10 * 5 = 2000 J.
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