Question

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

• A. 12 cm
• B. 4 cm
• C. 6 cm
• D. 8 cm

Answer 1

Answer: (B)

4 cm

The object shiftness $=t(1-\frac{{\mu }_s}{\mu })$

where, $t=$ thickness of $s\mathrm{la}b=36cm$ ${\mu }_s=$ refractive index of surrounding (i.e. water)

$=4/3$

$\mu =$ refractive index of

$\mathrm{slab}=\frac{3}{2}$

$\begin{array}{cc}\text{Shifthess}& =36(1-\frac{4/3}{3/2})\\ & =36(1-\frac{8}{9})=4cm\end{array}$