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The free end of a thread wound on a bobb...

The free end of a thread wound on a bobbin is passed round a nail A hammered into the wall. The thread is pulled at a constant velocity 'v' . Assuming pure rolling of bobin, find the velocity `v_(0)` of the centre of the bobbin at the instant when the thread forms an angle `alpha` with the vertical: (`R` and `r` are outer and inner radii off the babbin)

Text Solution

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The correct Answer is:
`(Rv)/(R sin alpha - r)`
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