A plano convex lens of refractive index and focal length is kept in contact with…

PHYSICS · Single correct · CBSE · Physics · Light — Reflection and Refraction · Light — Reflection and Refraction

Problem

A plano convex lens of refractive index

\mu_1

and focal length

f_1

is kept in contact with another plano concave lens of refractive index

\mu_2

and focal length

f_2

. If the radius of curvature of their spherical faces is

R

each and

f_1 = 2f_2

, then

\mu_1

and

\mu_2

are related as: (1)

\mu_1 + \mu_2 = 3

(2)

2\mu_1 - \mu_2 = 1

(3)

3\mu_2 - 2\mu_1 = 1

(4)

2\mu_2 - \mu_1 = 1