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प्रश्न
State whether work is done or not, by writing yes or no, in the following case:
A boy climbs up 20 stairs.
विकल्प
Yes
No
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उत्तर
Yes
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संबंधित प्रश्न
It takes 20 s for a person A of mass 50 kg to climb up the stairs, while another person B does the same in 15 s. Compare the work done.
A boy weighing 25 kgf climbs up from the first floor at height 3 m above the ground to the third floor at height 9m above the ground. What will be the increase in his gravitational potential energy? (Take g = 10 N kg -1)
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(i) Which force has the least moment about O? Give a reason.
(ii)Which force has the greatest moment about O? Give a reason.
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What is the ratio of SI units to CGS units of 'work'?
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