For light incident from air onto a slab of refractive index 2. Maximum possible angle of refraction is,

Options

A. `30^(@)`
B. `45^(@)`
C. `60^(@)`
D. `90^(@)`

Answer

C

Explanation

From Snell.s law, `mu = (sin I)/(sin r)`
Now consider an angle of incident is `90^(@)`
`sir r = (sin 90^(@))/(2)`
`r = sin^(-1) (0.5)`
`r = 30^(@)`