Find the angle of refraction in a medium `(mu=2)` if light is incident in vacuum, making an angle equal to twice the critical angle.

Explanation

Since the incident light is in rarer medium. Total Internal Reflection can not take place.
`C="sin"^(-1)1/mu=30^(@)`
`rArr :. i=2C=60^(@)`
Applying Snell's Law. `1 sin 60^(@) = 2 sin r`
`sin r=sqrt(3)/4`
`rArr r=sin^(-1) (sqrt(3)/4)`