Question

When a ray of light is refracted, the wavelength of the refracted light changes. Identify which of the following explain this phenomenon?
I. Some of the energy of the incident ray is carried away by the reflected ray
II. The boundary surface absorbs some of the energy of the incident ray
III. The incident and refracted rays do not travel with the same velocity

• A. I only
• B. II only
• C. III only
• D. I and II only
• E. I, II, and III

Answer 1

Answer: (C)

III only

Wavelength of the light in a medium ${\lambda }_m=\frac{v_m}{\nu }$ where $v_m$ is the velocity of light in that medium

The velocity with which the incident and the refracted ray travels is not same but the frequency of both the rays is same. Hence the wavelength of the refracted light changes w.r.t the incident light.

Hence option C is correct.