Question

A YDSE is conducted in water $\left(\mu_1\right)$ as shown in figure. A glass plate of thickness $t$ and refractive index $\mu_2$ is placed in the path of $S_2$. The optical path difference at $O$ is

• A. $\left(\mu_2-1\right) t$
• B. $\left(\mu_1-1\right) t$
• C. $\left(\frac{\mu_2}{\mu_1}-1\right) t$
• D. $\left(\mu_2-\mu_1\right) t$

Answer 1

Answer: (D)

Optical path difference
$\Delta x=\left(\mu_2-\mu_1\right) t$