Question

Human eye is most sensitive to
(A) Red Colour
(B) Green Colour
(C) Violet Colour
(D) Orange Colour

Answer 1

Hint:- The human eye is a specialised sense organ which has the ability to react to light and helps in perceiving visual images which are further processed by the brain. The eyes are located in a bony cavity called orbits which gives protection and maintains a proper structure.

Complete solution:
The eye is composed of three coats or layers. Outermost coat is composed of Cornea and Sclera. The middle layer is called Uvea which is composed of Choroid, Ciliary Body and Iris. The innermost layer is called the Retina and is a light sensitive layer of the eye, present in almost every vertebrate. Retina has rod and cone cells which allows light perception and helps in colour differentiation and perception of depth. Human eye can differentiate between 10 million colours and can possibly detect a single photon. Cones are composed of three different photopigments called the Opsin pigments for Red, Green and Blue colour. A curve is obtained which shows the response of the eye under normal lighting conditions. This curve peaks at 555 nanometers of wavelength which corresponds to green colour in the normal visible spectrum of light, which means under normal lighting conditions, the eye is most sensitive to Green colour.
So, the correct answer is Option (B) - Green.

Note:- Instead of having a high sensitivity of the human eye towards Green colour, danger signals have red colour. The reason is because green colour is almost present everywhere in nature, so it will attract very little attention by people and the other main reason is because it has the longest wavelength and hence is least scattered, that's why it can be perceived from a long distance.