A small plane mirror is rotating at a constant frequency of n rotation per second. With what linear velocity will a light spot move along a spherical screen of radius of curvature of R metres if the mirror at the centre of curvature of the screen?

A small plane mirror is rotating at a constant frequency of n rotation

1.	A small plane mirror is rotating at a constant frequency of n rotation per second. With what linear velocity will a light spot move along a spherical screen of radius of curvature of R metres if the mirror at the centre of curvature of the screen?
Answer» `4pinR` `2pinR` `PI N R` `4N R` ANSWER :A