A ray of light is incident on the surface of separation of a medium at an angle `45^(@)` and is refracted in the medium at an angle `30^(@)`. What will be the speed of light in the medium?

Options

A. `1.96xx10^(8)ms^(-1)`
B. `2.12xx10^(8)ms^(-1)`
C. `3.18xx10^(8)ms^(-1)`
D. `3.33xx10^(8)ms^(-1)`

Explanation

(b) `n=(sin i )/(sin r)=c/v`

Hence `v=( c sin r)/(sin i)=(3xx10^(8)xxsin30^(@))/(sin 45^(@))`
`=(3xx10^(8))/(sqrt(2))=2.12xx10^(8)ms^(-1)`