Question

You are given four source of light each one a providing a light of a single colour of a single colour – red, blue, green and yellow. Suppose the angle of refraction for a beam of yellow light corresponding to a particular angle of incidence at the interface of two media is 90⁰. Which of the following statement is correct, if the source of yellow light is replacement with that of other lights without changing the angle of incidence?

• A. The beam of red light would undergo total internal reflection.
• B. The beam of red light would bend towards normal while it gets refracted through the second medium.
• C. The beam of blue light would undergo total internal reflection.
• D. The beam of green light would bend away from the normal as it gets refracted through the second medium.

Answer 1

Answer: (C)

The beam of blue light would undergo total internal reflection.

Answer 2

: Here, for yellow light, when i = C. as I is kept same, C must be smaller for total internal reflection. From will be smallest for blue colour, Therefore, blue light would udergo total internal reflection.