A half spherical glass lens with refractive index 1.5 is placed in a liquid with refractive index of 1.3 (see following figure). The radius of the half spherical lens is 10 ~cm . A parallel beam of light travelling in the liquid is refracted by the glass lens. Then the absolute value of the position of the image from the centre of the glass lens will be

Step-by-step solution

Focal length of the lens, 1 f = ( n₂ n₁ -1 ) ( 1 R₁ - 1 R₂ ) Here, refractive index for glass lens, n₂=1.5 Refractive index for water, n₁=1.3 Radius of curvature, R₁=10 ~cm , R₂= Putting these values, we get aligned 1 f & = ( 1.5 1.3 -1 ) ( 1 10 - 1 ) 1 f & = 015 10 f & =65 ~cm aligned Now, paralleI beam of light will converge at the focus of lens, so image position v=65 ~cm .