One surface of radius of curvature of a convexo-convex lens of material of refractive…

PHYSICS · Subjective · CBSE · Physics · Ray Optics and Optical Instruments · Ray Optics and Optical Instruments

Problem

One surface of radius of curvature

R_2 = 120\text{ cm}

of a convexo-convex lens of material of refractive index

\mu = 1.5

and focal length

f_1 = 40\text{ cm}

is silvered. It is placed on a horizontal surface with the silvered surface in contact with it. Another convex lens of focal length

f_2 = 20\text{ cm}

is fixed coaxially at

d = 10\text{ cm}

above the first lens. A luminous point object

O

on the axis gives rise to an image coincident with itself. Find its height above the upper lens.