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

Options

A. `sqrt(3)`
B. `(3)/(2)`
C. `sqrt((3)/(2)`
D. 2

Answer

C

Explanation

Angle of refraction `r = 60^(@)`, Angle of incident `I = 30^(@)`
`sin r = n xx sin r`
`n = (sin 30^(@))/(sin 60^(@)) = sqrt(3)`