Question

A wavefront $A B$ moving in air is incident on a plane glass surface $X Y$, as given in figure. Its Position $C D$ after refraction through a glass slab is shown along with normals drawn at $A$ and $D .$ The refractive index of glass with respect to air is given by

• A. $\frac{\sin \theta}{\sin \theta^{\prime}}$
• B. $\frac{\sin \phi}{\sin \theta}$
• C. $\frac{\sin \theta}{\sin \phi^{\prime}}$
• D. $\frac{A B}{C D}$

Answer 1

Answer: (C)

The angle of incidence $i=\theta$ and the angle of refraction $r=\phi^{\prime}$ According to Snell's law, $\frac{\sin i}{\sin r}=\mu=\frac{\sin \theta}{\sin \phi^{\prime}}$