Question

When the angle of incidence for light travelling from a denser medium to a rarer medium is greater than the critical angle, the result is:

Options

• the refracted ray travels along the interface

• refraction occurs, with the refracted ray bending away from the normal

• the angle of refraction becomes \[90^\circ\]

• total internal reflection, with the light returning fully into the denser medium

Answer 1

When the angle of incidence exceeds the critical angle, refraction stops and the ray is reflected completely inside the denser medium. This complete reflection back into the denser medium is total internal reflection.