Question

An optometrist examined john’s eyes. The farthest object he can clearly focus on with his right eye is 50 cm away. What is the power of the contact lens required to correct the vision in his right eye?

(a) ­  -0.50 diopters

(b)  - ­ 2.0 diopters

(c)   + 2.0 diopters

(d)   + 5.0 diopters

Answer 1

Correct option   (b) -2.0 diopters

Explanation :

For point of eye = ∞ , power of his eye = - 2D

To mate power zero, i.e. for point ­ - ∞,

power to be attached = ­2D