Question

A student needs spectacles of power-0.5 D for the correction of his vision.
(i) Name te defect in vision the student is suffering from.
(ii) Find the nature and focal length of the corrective lens.
(iii) List two causes of this defect

Answer 1

1) myopia

2) Concave lens

p= 1/f

-0.5 = 1/f

f= - 1/0.5

f= -2

3) excessive curvature of lens

and elongation of eyeball

hope it helps you

Answer 2

1.he is suffering from myopia or nearsightedness.

2.the corrective lens used is concave lens and focal length is 2.

3.elongation of eyeball

Increase in distance between lens and retina