The speed of light in air and glass is `3 xx 10^(8) m//s`, and `2 xx 10^(8)m//s` respectively. A beam of light falls on a glass at an angle of `30^(@)` with the surface. The angle of refraction in glass is

Options

A. `25^(@)16'`
B. `35^(@)16`
C. `15^(@)26`
D. `30^(@)16`

Answer

B

Explanation

`mu = (v_(a))/(v_(g)) = (sin i)/(sin r)`
`sin r = (v_(g))/(v_(a)) xx sin r = (2 xx 10^(8))/(3 xx 10^(8)) xx 0.8666`
`r = sin^(-1)(0.5773) = 35^(@)16'`