Question

Two parallel rays are travelling in a medium of refractive index ${\mu }_1=\frac{4}{3}$. One of the rays passes through a parallel glass slab of thickness $t$ and refractive index ${\mu }_2=\frac{3}{2}$. The path difference between the two rays due to the glass slab will be

• A. $\frac{4t}{3}$
• B. $\frac{3t}{2}$
• C. $\frac{t}{8}$
• D. $\frac{t}{6}$

Answer 1

The correct option is C $\frac{t}{8}$

The path difference generated due to shift induced by the glass slab.

$\Delta x=(\frac{{\mu }_2}{{\mu }_1}-1)t$

$=(\frac{\left(\frac{3}{2}\right)}{\left(\frac{4}{3}\right)}-1)t=\frac{t}{8}$

Hence, option $\left(C\right)$ is correct.