Question

In hypermetropia, the image is formed
A. Before retina and is corrected by convex lens
B. Behind the retina and is corrected by convex lens
C. Before retina and is corrected by concave lens
D. Behind the retina and is corrected by convex lens

Answer 1

Hint:Hypermetropia is a disorder in which a person is unable to see clear images of nearby objects but can see distant images. Eye-glasses with converging lenses offer the additional focusing power needed to form the image on the retina.

Complete answer:
The ability of the eye lens to change its focal length is called accommodation. Sometimes the eye can progressively lose its power of accommodation. In such cases, the individual cannot see the objects clearly and comfortably. The vision is distorted by the refractive defects of the eyes. The common defects of the eye are myopia or near-sightedness, hypermetropia or far-sightedness, and presbyopia. These defects may be corrected with the use of appropriate spherical lenses.

Hypermetropia is also known as far-sightedness. Individuals with this condition cannot see the nearby objects as the near point for the individual is farther away from the standard near point (25 cm). This happens when light rays from the surrounding object are concentrated at the point behind the retina. This defect can arise if the eye lens has a longer focal length, or the eyeball is too small. A convex lens with appropriate power can be used to correct this defect.

Thus, the correct answer is option B i.e., Behind the retina and is corrected by convex lens.

Note:The retina is a sensitive membrane that has large numbers of light-sensitive cells. When illuminated, the light-sensitive cells get triggered and produce electrical signals. The signals are transmitted via the optic nerves into the brain. These signals are then interpreted by the brain, and eventually the information is interpreted so that we perceive things as they are.