Question

An object is seen through a glass slab of thickness 36 cm and refractive index 3/2. The observer, object and the slab are dipped in water (n= 4/3). the shift produced in the position of the object is

• A. 12 cm
• B. 4 cm
• C. cannot be calculated
• D. 9/2 cm

Answer 1

The correct option is B 4 cm

Shift produced in the position of the object-

$s=\left(1-\frac{{\mu }_{medium}}{{\mu }_{slab}}\right)\times t$

Here,

${\mu }_{medium}$ is the refractive index of the surrounding medium

${\mu }_{slab}$ is the refractive index of the slab material

$t$ is the thickness of the slab

We put all the values and get-

$s=\left(1-\frac{\left(4/3\right)}{\left(3/2\right)}\right)\times 36\text{cm}$

$s=\left(1-\frac{8}{9}\right)\times 36\text{cm}$

$s=\left(\frac{1}{9}\right)\times 36\text{cm}$

$s=4\text{cm}$

So, option (B) Is correct.