Question

Total internal reflection takes place when the light ray travels from ______

• A. Rarer to denser medium
• B. Rarer to rarer medium
• C. Denser to rarer medium
• D. Denser to denser medium

Answer 1

Answer: (C)

Total internal reflection always place when a light ray travels from an optically denser medium to a rarer medium.

For total internal reflection, angle of incidence must be greater than the critical angle,

$C={\sin }^{-1}\frac{1}{\mu }$ where, $\mu$=refractive index of denser medium relative to rarer medium.

Answer-(C)