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
The Problem
Consider the given arrangement:
Point $P$ is equidistant from $S_1$ and $S_2$ .The glass slab in air has refractive index $\mu_{2}$, and the one in water($\mu_{1}$) has refractive index $\mu_{3}$. We need to find the relation between $\mu_{2}$ and $\mu_{3}$ such that $P$ is the cent...