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प्रश्न
In which of the following cases, is work being done?
(i) A man pushing a wall.
(ii) a coolie standing with a load of 12 kgf on his head.
(iii) A boy climbing up a staircase.
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उत्तर
Work is done only in case of a boy climbing up a stair case.
संबंधित प्रश्न
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