A parallel beam of monochromatic light is incident on the surface of water having refractive index 4/3. The direction of the incidence beam bisects the angle between the normal to the water surface and the water surface. The angles of incidence and refraction are

Options

A. `i=30^(@), r=20^(@)`
B. `i=45^(@),r=20^(@)`
C. `i=45^(@),r=32^(@)`
D. `i=60^(@), r=40^(@)`

Answer

C

Explanation

`i=45^(@) and sin r=(sin i)/(n)=(sin 45^@)/(4//3)`
`:. sin r =(3)/(sqrt(2) xx 4)=(3)/(5.656) :. r=32^(@)`