Question

Which of the following sources of light is different from others?
A) Sunlight
B) White light
C) Light from a bulb
D) Sodium light

Answer 1

Hint: The process of Refraction for different lights through prisms give different spectrum of constituent colours based on the characteristics of the light passed. The lights may contain different colours or single colour within it.

Complete step by step solution:
We all know that when a light is passed through a prism, refraction takes place. Let us recall about refraction now. Refraction is a process of bending the light beam at the edges of different mediums when it passes through them. And we know that, when passed through a prism, sunlight, white light and light from a bulb separates into the individual colour bands like the rainbow. But in the case of sodium light, when it is passed through a prism, it will not split into its constituent colours. Because sodium light is a monochromatic light.

Among all these lights, only sodium light is monochromatic light. There are two kinds of sodium lights, Low pressure and High pressure. We can mainly see these lights for industrial purposes as well as in street lighting. And it shines in a monochrome slightly yellowish light.

By analysing all the data above, we understand that sodium light is the different one.

Final Answer is: Option (D), Sodium light.

Note: A monochromatic light is the kind of light which only has one constituent colour. It is also a light of single wave-length. So upon refraction we cannot separate it into different colour spectrum. When light is passed through prism, white light is split into its constituent colours in the process called dispersion.