A ray of light travelling in a transparent medium f refractive index `mu`, falls on a surface separating the medium from air at an angle of incidence of `45^(@)`. For which of the following value of `mu` the ray can undergo total internal reflection ?

Options

A. `mu=1.33`
B. `mu=1.40`
C. `mu=1.50`
D. `mu =1.25`

Answer

C

Explanation

For TIR `45 ge theta _(C) implies sin 45 ge sin theta _(c)`
`implies (1)/(sqrt(2))ge(1)/(mu)implies mu ge sqrt(2)`