A beam of light travelling in water is incident on a glass which is immersed in the water. The incident beam makes an angle of \(40^o\) with the normal. Calculate the angle of refraction in the glass.

[Refractive index of water = 1.33, Refractive index of glass = 1.5]

A.

\(29.36^o\)

B.

\(25.37^o\)

C.

\(37.21^o\)

D.

\(34.75^o\)

Correct answer is D

\(n_1\)=1.33; \(n_2\)=1.5;  i=40°; r= ?

from snell's law:

\(n_1\) x sin i=\(n_2\)x sin r

⇒1.33 x sin 40°=1.5 x sin r

⇒sin r = 0.5700

⇒r = \(sin^{-1}\) (0.5700)

 ⇒ r = 34.75