At what angle of incidence should a light beam strike a glass slab of refractive index `sqrt3`, such that the reflected and the refracted rays are perpendicular to each other ?

Explanation

From the figure, `i+90^(@)+r=180^(@)`
or, `i+r=90^(@)orr=90^(@)-i`
`thereforemu=sini/sinr=sini/(sin(90^(@)-i))=sini/cosi=tani`
`thereforei=tan^(-1)(mu)=tan^(-1)(sqrt3)=60^(@)`