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प्रश्न
A boy pulls a box up to 10 m with a force of 5 kgf. Calculate the work done by him.
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उत्तर
Given, force = 5kgf = 5 kgf x 10 ms-2= 50N
displacement = 10m
Work done = force x displacement = 50 x 10 = 500J
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