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]

Options

A. `e=0.50`
B. `e=0.75`
C. `e=0.25`
D. None of these

Explanation

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