Question

A ray of light is incident on a glass plate at an angle of60 digree what would be the refractive index of glass if reflected rays are prependicular to each other?

Answer 1

60 degree from normal is 30 degree from parallel . so reflected ray is 30 degrees from parallel to surface.

If reflected ray is perpendicular to reflected ray, that is be 30 degree from surface and another 60 up from parallel on other side.

Half the incidence angle .

N1 (sin60)=N2 (sin30)
here N1(air)~=1

N2=sin60/sin30



$\huge\mathfrak\red{Thanks.}$