A ball is kept at a height h above the surface of a heavy transparent sphere made of a material of refractive index The radius of the sphere is R. At t = 0, the ball is dropped to fall normally on the sphere. Find the speed of the image formed as a function of time for `tlt sqrt((2h)/g)`. Consider only the image by a single refraction.

Answer

`(muR^(2)g t)/([(mu-1)(y_(0)-(1)/(2)g t^(2))-R]^(2))`