Question

A student uses spectacles of number -2 for
seeing distant objects. Commonly used
lenses for her/his spectacles are
(A) bi-concave
(B) double concave
(C) concavo-convex
(D) convexo-concave​

Answer 1

Answer:

d convexo concave ....

Answer 2

Answer:

(D). Convexo-concave

Explanation:

If a person has -2 eyesight that means the person has Near-sightedness that is also called as Myopia as he is not capable of seeing thew distant objects.

The Convexo-concave lens also called as Meniscus lenses are used for the corrective lenses. The Convexo-concave lenses can have both the positive and negative power of the lens that is dependent on the relative curvature of the two surfaces of the lens. In these lenses the convex face of the lens has higher degree of curvature than the Concave face of the lens.

Therefore, the commonly use lenses for his/her spectacles are Convexo-concave lenses.

Hence, the correct option is (D).