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A boy of mass 40 kg climbs a staircase of 20 steps, each 15 cm high, in 10 s. Calculate the power he develops. Take g = 10 m s−2.
Original Khojo Papers practice question — not from a past board paper.
Answer
120 W
No citable source has been recorded for this record. Treat it as practice material, not as fact.
Explanation
The total height is 20 × 0.15 = 3 m, so the work done is 40 × 10 × 3 = 1200 J and the power is 1200 ÷ 10 = 120 W.
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