The person is having myopia. In this defect, a person cannot see objects beyond near point or far objects but can see the near objects clearly

This defect can be corrected by using convex lens.

Given distance of far point (D) = 2m

Let f be the focal length of eye lens.

⇒ f = -D = -2 cm.

Power of a lens =

⇒ Power =

Hence the power of the lens is -0.5 D