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A bullet is moving horizontally with cer...

A bullet is moving horizontally with certain velocity. It pierces two paper discs rotating coaxially with angular speed `omega` separated by a distance l. IF the hole made by bullet on second disc is shifted by an angle `theta` with respect to the first, find velocity of bullet.

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Let the bullet take a time t to travel from one disc to the other with a velocity
`implies`The distance between the discs
l=vt
`impliest=(l)/(v)`
When the bullet is about to hit the second disc at Q, the hole made by the bullet on the first disc at P will rotate through an angle during the time t
`implies theta=omegat`
Using (1)&(2)
`t=(l)/(v)=theta//omega`
`impliesv=omegal//theata`
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