Question

from Standard IX user spectacles the power of the lens is in his spectacles is minus 0.5 D answer the following questions state the type of lenses used in his pectorals B name the defect of vision Aniket is suffering from c find the focal length of the lens is used in his spectacles

Answer 1

P = 1/f

0.5 = 1/f in meters

F=1/0.5

F=2 m

He is suffering from hypermeteropia

Answer 2

1) As power is positive, the lens is a convex lens
2) As Ankit uses a convex lens, he suffers from Hypermetropia (farsightedness)
3) focal length= 1/power
= 1/0.5
=2