Question

If Observer and Object are present in air medium, then find the net shift in position of object produced due to the combination of glass slabs as seen from the side of an observer $O^{\prime }$.

• A. $20\text{cm}$
• B. $30\text{cm}$
• C. $15\text{cm}$
• D. $25\text{cm}$

Answer 1

The correct option is C $15\text{cm}$

We know that,
Net shift $\left(S_{net}\right)=$ Shift due to slab $1$ $\left(S_1\right)$$+$Shift due to slab $2$ $\left(S_2\right)$$+$Shift due to slab $3$ $\left(S_3\right)$

$S_1=t_1(1-\frac{1}{{\mu }_1})=10(1-\frac{1}{2})=5\text{cm}$

$S_2=t_2(1-\frac{1}{{\mu }_2})=15(1-\frac{1}{1.5})=5\text{cm}$

$S_3=t_3(1-\frac{1}{{\mu }_3})=10(1-\frac{1}{2})=5\text{cm}$

$S_{net}=(5+5+5)\text{cm}=15\text{cm}$

Hence, option (c) is the correct answer.

Why this question? This question will make the students learn how to extend the concept of shift due to glass slab to solve the problems of composite glass slab system.