A convex spherical refracting surface separates air and glass

PHYSICS · Single correct · CBSE · Physics · Ray Optics and Optical Instruments · Ray Optics and Optical Instruments

Problem

A convex spherical refracting surface separates air and glass, with

\mu_g=1.5

. If the image is to be real, at what minimum distance

u

should the object be placed in air, where

R

is the radius of curvature? (1)

u>3R

(2)

u>2R

(3)

u<4R

(4)

u<R