A ray of light falls on a transparent glass slab of refractive index 1.62. What is the angle of incidence if the reflected ray and refracted ray are mutually perpendicular?

Options

A. `tan^(-1)(1.62)`
B. `tan^(-1)(1/1.162)`
C. `1/(tan^(-1)(1.62))`
D. none of these

Explanation

(a) Here `/_i+90^(2)+/_r=180^(@)`
`i+r=90^(@)`
`r=(90^(@)-i)`
From Snel's law
`mu=(sin i)/(sin r)=(sin i)/(sin(90^(@)-i))`
`=(sin i)/(cos i)=tan i`
`mu=tani`
`i=tan^(-1)(mu)`
`i=tan^(-1)(1.62)`