In the diagram above a beam of white light travels from a rare to a dense medium. What colours of light do the rays a, b and c respectively represents?

In the diagram above a beam of white light travels from a rare to a dense medium. What colours of light do the rays a, b and c respectively represents?

Answer Details

When a beam of white light passes from a rare medium (e.g. air) to a dense medium (e.g. glass), it bends or refracts towards the normal (the line perpendicular to the surface). The degree of bending depends on the wavelength (or color) of the light. The shorter the wavelength, the more the light bends. In the given diagram, the red ray (a) is the least bent, while the blue ray (c) is the most bent. The green ray (b) is somewhere in between. This means that the colors are separated out as they pass through the medium, with the shorter wavelengths (violet, blue, and green) bending more than the longer wavelengths (yellow, orange, and red). Therefore, the correct answer is: red, green, and blue, as shown in.