A ray of light is incident on the interface between water and glass at an angle `i` and refracted parallel to the water surface, then value of `mu_(g)` will be

Options

A. `(4//3) sin i`
B. `1/(sin i)`
C. `4/3`
D. `1`

Answer

B

Explanation

`g mu_w = (sin i)/(sin r)`
`""_(g)mu_a = (sin r)/(sin 90^@)`
`implies ""_(g)mu_w = xx ""_wmu_a = (sin i)/(sin r) xx (sin r)/(sin 90^@) = sin i`
or `(mu_w)/(mu_g) xx (mu_a)/(mu_w) = sin i`
`implies mu_g = 1/(sin i)`