A ray of light travelling inside a rectangular glass block of refractive index`sqrt 2 `is incident on the glass-air surface at an angle of incidence of `45^(@)`. The refractive index of air is one. Under these conditions the ray will

Options

A. emerge into the air without any deviation
B. be reflected back into the glass
C. be absorbed
D. emerge into the air with an angle of refraction equal to `90^(@)`

Answer

D

Explanation

`sinC=(1)/(mu)=(1)/(sqrt2) or (sin 45^(@))/(sinr)=(1)/(sqrt2)`
`sinr=1 or r=90^(@)`