Question

Light is incident on the interface of glass and air as shown in the figure. If the green light is just totally internally reflected then the emerging ray in the air contains.

Answer 1

Explanation:

1. We know that white light is composed of a band of colours arranged in red, orange, yellow, green, blue, indigo, and violet.
2. When the green light is just totally internally reflected, the emerging ray in the air contains yellow, orange, and red colours.
3. We know, the relation between wavelength and refractive index is given by

$\lambda =\frac{{\lambda }_0}{n}$, Where $\lambda$=wave length, ${\lambda }_0$= wavelength of light in vacuum, $n$= Refractive index.

So $\lambda \propto \frac{1}{n}$, as $\lambda$ increases, the refractive index decreases and vice versa.

As red, yellow and orange colours have more wavelength, the refractive index will be minimum.

Hence, the emerging ray in the air contains yellow, orange and red colours.