Total internal reflection can take only if

Options

A. light goes from optically rarer medium (smaller refractive index) to optically denser medium
B. light goes from optically denser medium to rarer medium
C. the refractive indices of the two media are close to different
D. the refractive indices of the two media are widely different

Answer

B

Explanation

According to Snell.s Law, `(sini)/(sinr)=(mu_(2))/(mu_(1))`
were `r=90^(@)` for particular incidence angle called critical angle. When the incidence angle is equal to or greater than `i_(c)`, then total internal reflection occurs. It takes place when ray of light travels from optically denser medium `(mu_(1) gt mu_(2))` to optically rarer medium.