A person holds a bundle of hay over his head for 30 minutes and gets tired. Has he done some work or not? Justify your answer.

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Chapter 10 NCERT Class 9 Science SOLUTIONS

13. A person holds a bundle of hay over his head for 30 minutes and gets tired. Has he done some work or not? Justify your answer.

Question:

A person holds a bundle of hay over his head for 30 minutes and gets tired. Has he done some work or not? Justify your answer.

Answer:

Of course, the person does not do any work on a bundle of hay. For this the reason is, no displacement is taking place in the bundle. There is no work in standing with a burden on head. There must be displacement for work.

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