Question

A beam of light is converging towards a point I on a screen. A plane glass plate whose thickness in the direction of the beam = t, refractive index =$\mu$ , is introduced in the path of the beam. The convergence point is shifted by

• A. $t(1-\frac{1}{\mu })$ away
• B. $t(1+\frac{1}{\mu })$ away
• C. $t(1-\frac{1}{\mu })$ nearer
• D. $t(1+\frac{1}{\mu })$ nearer

Answer 1

The correct option is A

$t(1-\frac{1}{\mu })$ away

Normal shift $△x=(1-\frac{1}{\mu })t$

and shift takes place in direction of ray.