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

Options

A. 2.5 cm
B. 1.67 cm
C. 1.5 cm
D. 5 cm

Answer

A

Explanation

`(1)/(f) = (1)/(v) - (1)/(u) = (1)/((1)/(40)) - (1)/(u) " " :. u = (1)/(40)m = 2.5 cm`