Physics
A man moves in a circular path in a horizontal plane, the work done is :
- Positive
- Negative
- Zero
- Cannot say
Work, Energy & Power
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Answer
Zero
Reason — Work done is equal to the product of force, displacement and cosine of the angle θ between the directions of force F and displacement S i.e., W = F x S cosθ.
When a body moves in a circular path in a horizontal plane, no work is done since the centripetal force on the body at any instant is directed towards the centre of the circular path and the displacement at that instant is along the tangent to the circular path, i.e., normal to the direction of force on the body (i.e. θ = 90°)
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