(a) A point object ?O? is kept in a medium of refractive index n₁ in front of a convex spherical surface of radius of curvature R which separates the second medium of refractive index n₂ from the first one, as show in the figure.Draw the ray diagram showing the image formation and deduce the relationship between the object distance and the image distance in terms of n₁, n₂ and R.(b) When the image formed above acts as a virtual object for a concave spherical surface separating the medium n₂ from n₂ (n₂ > n₁), draw this ray diagram and write the similar [similar to (a)] relation. Hence obtain the expression for the lens maker?s formula.

121 11 11 -R