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प्रश्न
State the amount of work done by an object when it moves in a circular path for one complete rotation. Give a reason to justify your answer.
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उत्तर
Amount of work done is equal to zero.
Work is said to be done only when there is displacement produced. In the case of a body moving in a circular path, the body comes to its original place, therefore, there is no displacement, and hence work is zero.
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| S. No | Activity | Work done or not done |
| 1. | Pushing the door | |
| 2. | Holding a doll | |
| 3. | Sitting in a bus | |
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