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प्रश्न
A girl of mass 35 kg climbs up from the first floor of a building at a height 4 m above the ground to the third floor at a height 12 m above the ground. What will be the increase in her gravitational potential energy? [g = 10 ms-2]
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उत्तर
Increase in gravitational energy
= mg (h2 − h1)
= 35 × 10 (12 − 4)
= 350 × 8
= 2,800 J
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