Question

(a) A student is unable to see clearly the words written on the black board placed at a distance of approximately 3 m of him. name the defect of the boy is suffering from.state the possible cause of this defect and explain the method of correcting it ?

Answer 1

Defect of vision: Myopia or short sightedness or near sightedness

Causes of myopia:

Excessive curvature of eye lens; eye lens becomes more convergingElongation of eye ball

Methods of correction:

By the use of concave lens of suitable power or focal length the defect is corrected.

Answer 2

by using bi concave lens....