Question

What kind of lens is there in our eyes?

• A. concave
• B. convex
• C. Plano-concave
• D. Plano-convex

Answer 1

The correct option is B convex

Answer is B.
Our eye lenses are convex lenses with variable focal lengths. The focal length of the eye lens is controlled by muscles according to the distance of the object from us that we are trying to see. The lens is flexible and when it is acted on by the ciliary muscle around it, the lens can be "flattened" to change the focus, or, when the muscle is relaxed, the lens can be assumed as having a more spherical shape. This is the principle of the eye to focus on objects nearer or farther away.