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CBSE Class 9 Answered

What is the work done by a man in carrying a suitcase weighing 30 kg over his head, when he travels a distance of 10 m in the (i) vertical direction (ii) horizontal direction.
Asked by swainanirudha1 | 21 Dec, 2018, 06:28: AM
answered-by-expert Expert Answer
In Horizontal direction workdone is zero, because when the person moves in horizontal direction gravitational force is in vertical direction.
Hence direction of force and direction of movement are in mutually perpendicular direction and workdone is zero.
 
In vertical direction,  workdone is  m×g×h = 30×9.8×10 = 2940 Joules
Answered by Thiyagarajan K | 21 Dec, 2018, 06:52: AM

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