Question

Given below is a diagram showing a defect of human eye. Study it and answer the following questions.

(i) Name the defect shown in the figure.
(ii) Give reason for this defect of eye in human being.
(iii) Name the type of lens used to correct the eye defect.

Answer 1

(i) The defect shown in the figure is hypermetropia or long-sightedness.
(ii) Two possible reasons are
     a) Ciliary muscles have become weak, so the converging power of the eye lens decreases.
     b) Because of shortening of the eye ball or flattening of the eye lens.
(iii) To correct the eye defect, a suitable convex lens is used.