A ray of light is incident at the glass-water interface at an angle I, it emerges fimally parallel to the surface of water, the the value of `mu_g` would be

Options

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

Answer

B

Explanation

For glass`-` water interface `._(g)mu_(g)=(sin i)/(sin r)`.....(i)
For water `-` air `=(sinr )/(sin90^(@))` ….(ii)
`implies ._(g)mu_(w)xx._(w)mu_(a)=(sini)/(sinr)xx(sinr)/(sin 90^(@))=sin i`
`implies (mu_(w))/(mu_(g))xx(mu_(a))/(mu_(w))=siniimpliessiniimpliesmu_(g)=(1)/(sini)`