A man of 55 kg is holding a bucket of mass 25 kg. He walks 50 m on a level road at a constant speed of 3 ms" and then climbs up a hill of height 20 m. What is the work done by the man ?

A man of 55 kg is holding a bucket of mass 25 kg. He walks 50 m on a l

1.	A man of 55 kg is holding a bucket of mass 25 kg. He walks 50 m on a level road at a constant speed of 3 ms" and then climbs up a hill of height 20 m. What is the work done by the man ?
Answer» 16 KJ 12 KJ 3.5 KJ 2 KJ Solution :While walking WORK done is zero as FORCE and displacement are `bot` to each other and there is no net force along HORIZONTAL as the speed is constant. `:.` work is done in climbing the hill. `W=(M+m)gh=(55+25)xx10xx20=16000 J` = 16 J

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A man of 55 kg is holding a bucket of mass 25 kg. He walks 50 m on a level road at a constant speed of 3 ms" and then climbs up a hill of height 20 m. What is the work done by the man ?

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