Question

The condition(s) for total internal reflection is/are:

• A. Light must travel from denser to rarer medium.
• B. The angle of incidence should be greater than the critical angle.
• C. The angle of incidence should be greater than the angle of refraction.
• D. The angle of incidence should be greater than the angle of reflection.

Answer 1

Answer: (A), (B)

The angle of incidence should be greater than the critical angle.

When a ray of light passes from a medium of higher optical density to a medium of lower optical density at an angle of incidence greater than the critical angle, the ray is reflected back to the same medium. This phenomenon is the total internal reflection. During total internal reflection, angle of incidence is equal to angle of reflection.