Physics
State whether work is done or not by writing yes or no, in the following cases?
(a) A man pushes a wall.
(b) A coolie stands with a box on his head for 15 min.
(c) A boy climbs up 20 stairs.
Work, Energy & Power
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Answer
(a) No, work is not done by the man.
(b) No, work is not done by the coolie.
(c) Yes, work is done by the boy in climbing up the 20 stairs.
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