A ray of light is lncident on a glass plate at `60^(@)`. The reflected and refracted rays are found to be mutually perpe:ndiwlar. The refractive index of the glass is

Options

A. 0.866
B. 1.5
C. 1.732
D. 2

Answer

C

Explanation

Here `i=60^(@)`. As the angle between reflected and refracted ray is `90^(@),` then `i+r=90 or r=30^(@)`
Now `mu=(sini)/(sinr)=(sin60)/(sin30)=(sqrt3//2)/(1//2)=sqrt3=1.732`
The angle for which `i+r=90^(@)`, called Brewster. Angle.