A ray of light strikes a glass plate at an angle of 60°. If the reflected and refracted rays are perpendicular to each other then the refractive index of glass is

1.732

The correct answer is Option (2) → 1.732

According to Snell's law,

$n_1\sin θ_i=n_2\sin θ_t$

where,

$n_1$, Refractive index of Air (Ray initially in air) $n_1=1$

$n_2$, Refractive index of glass.

$θ_i$ = Angle of incidence = 60°

$θ_i+θ_t=90°$ [formula]

$θ_t=30°$

$∴1×\sin 60=n\sin 30$

$n=\frac{\sqrt{3}}{2}×\frac{1}{2}=\sqrt{3}=1.732$