Question

Convex lens is used to correct
A. Hypermetropia
B. Myopia
C. Cataract
D. Glaucoma

Answer 1

Hint:Convex optical lenses are used to bend light rays slightly inwards (called plus lenses). When traveling through the cornea and lens, the light rays then have a narrower angle to bend back to focus. As a consequence, on the eye, the light rays focus more forward.

Complete answer:When the light behind the retina is concentrated, hypermetropia occurs. The lens, therefore, adjusts its thickness, which helps to concentrate the light on the retina - a mechanism called accommodation. However, people with long sight are unable to completely cope, because the light does not focus sharply and vision is blurred. That is because the cornea is too thin, because the cornea is too low, or because the lens cannot be round enough. With glasses, the easiest, cheapest, and most reliable way to correct long-sightedness.
Hypermetropia is when the eye is shorter than the average case, and if the target object is closer, the vision focuses behind the retina. This means that even when it hits the retina, it does not focus.
Myopia is the condition when the eye is too long than the usual condition and when the target object is far away, the image falls short of the retina. In simpler terms, if the eye has myopia, then the eye will become too long and the image will fall short of the retina. And the eye is shorter in hypermetropia than in the normal case and the image is centered behind the retina. Hence a concave lens is suggested.
A cataract is an opacification of the eye's lens that leads to a loss of vision. Cataracts often grow slowly and one or both eyes may be affected. The solution is usually surgery.
Glaucoma is a category of eye disorders that affect the optic nerve, the well-being of which is essential for good vision. This damage is also caused by pressure in your eye that is abnormally high. For people above the age of 60, glaucoma is one of the main causes of blindness.

Therefore option A) is the correct answer that is Hypermetropia

Note: Few other applications of Convex lens are as followed:
In microscopes and magnifying glasses, a convex lens is used to combine all incoming light rays to a single point.
In cameras, a convex lens is used.
For hyperopia correction, a convex lens is used.
The converging lens is often used in the projector.