Rays from a lens are converging toward a point P, a shown in Figure. How much thick glass plate having refractive index 1.6 must be located between the lens and point P, so that the image will be formed at `P^(')`?

Options

A. 0.8cm
B. 1.6cm
C. 5cm
D. 2.4cm

Answer

A

Explanation

Due to the insertion of glass plate, the image has to be shifted by 0.3cm.
Shift produced by a glass slab of thickness t and refractive index `mu` is given by `(1-(1)/(mu))`.
So, `t[1-(1)/(1.6)]=0.3rArrt=0.8cm`