Question

Images formed on retina of human eye are:
A. Real
B. Virtual
C. Human eye adapts to form the image suitable
D. Both real and virtual

Answer 1

Hint: First recall about the human eye and its working. Then understand the phenomenon of refraction of light rays through the lens. Finally compare the above two and you will get an idea about the nature of image formed inside a human eye.

Complete step by step answer:
Human eye enables us to see.
Let us first understand how it works?
-Light rays enter the eye through the cornea. It is the front covering of an eye or the shield of an eye, to protect it from entrance of foreign particles. And the process of refraction begins in cornea.
-Then the light rays pass through the pupil, it controls the intensity of light entering the eye.
-After that light rays pass through the convex lens.
-Then the refracted rays pass through a dense substance. This substance is like a gel and is present in the eyeball.
-Finally the light rays form the image on the retina of an eye. Retina acts as a screen which is used to capture images.
Then this image is converted into electrical signals that are sent to the brain.
Also, we know that the images reflected from convex lenses are real in nature.
Thus, real images are formed on the retina of the human eye. Correct option is (A).
Additional Information:
There are two types of lens:
Convex lens- It is also known as converging lens.
Concave lens- It is also known as diverging lens.

Note: If a concave lens was used in place of a convex lens inside the human eye, then image formed would be virtual. But in the human eye a convex lens is present which forms a real image. Thus, options B,C,D are incorrect.