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प्रश्न
The world record for weight lifting was held by Sergei Didyk of the USSR. He lifted 261 kg to a height of 2.3 m in 4s; find:
(a) Weight lifted by him
(b) Work done by him
(c) Power developed by him. (g = 10m/s2)
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उत्तर
(a) Weight lifted by him = m × g = 261 × 10 = 2610 N.
(b) Work done by him = F × d = 261 × 2.3 J = 6003 J.
(c) Power developed by him =`("Work in J")/("Time in s")=6003/4"Watt"` = 1500.75 W.
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