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A ball is thrown from point A making an ...

A ball is thrown from point `A` making an angle `60^(@)` with line `OAS` as shown in the figure, where `OA=(R )/(sqrt(3))` [`O` is the centre of spherical surface of `PQS`]. If after striking the hemi-spherical surface, the ball rebounds in direction parallel to `OA`. The coefficient of restitution between the ball and the surface is [Neglect the effect of gravity any type of frictional force]

A

`e=0.50`

B

`e=0.75`

C

`e=0.25`

D

None of these

Text Solution

Verified by Experts

`(R )/(sin120^(@))=(R//sqrt(3))/(sintheta)`
`rArr sintheta=1//2rArrtheta=30^(@)`
Hence `e=1`
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