For the normal eye, the cornea of eye provides a converging power of 40D and the least converging power of the eye lens behind the cornea is 20D. Using this information, the distance between the retina and the eye lens of the eye can be estimated to be:

Options

(a) 2.5 cm
(b) 1.67 cm
(c) 1.5 cm
(d) 5 cm

Correct Answer:

2.5 cm

Explanation:

1/f = 1/v – 1/u
= 1/ 1 / 40 = 1/u
u = 1/40 m = 2.5 m