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प्रश्न
A man lifts a mass of 10 kg from the floor to a shelf 4 meter high. If g = 10 ms-2, what is the work done?
उत्तर
Given, mass m = 10kg; height h = 4m; g = 10ms²
W = mgh = 10 x 10 x 4 = 400J
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