Refractive indices of water an glass are `4//3 and 3//2` respectively. A ray of light travelling in water is incident on the water glass interface at `30^@`. Calculate the angle of refraction.

Options

A. `sin^(-1)""(3/4)`
B. `sin^(-1)""(2/3) `
C. `sin^(-1)""(4/9)`
D. `sin^(-1)""(8/9)`

Answer

C

Explanation

For a ray travelling from a medium of R.I. `n_1` to medium of R.I. `n_2 `.
`n_1 sin i=n_2 sin r `
`:. sinr=(n_(1))/(n_2)sin i=(4//3)/(3//2) xx sin 30^(@)`
`=(8)/(9) xx (1)/(2)=(4)/(9)`
`:. r=sin^(-1)""(4/9)`