Question

What is farsightedness ?

Hint:

A simple mnemonic: Farsightedness (Hypermetropia) means you can see FAR objects clearly. The correction is a CONVEX lens. In contrast, Nearsightedness (Myopia) means you can see NEAR objects clearly, and the correction is a CONCAVE lens.

Answer 1

Farsightedness, also known by its medical term hypermetropia, is a common defect of vision.
\[\begin{array}{rl} \bullet & \text{Definition: It is a condition in which a person can see distant objects clearly but finds it difficult to see nearby objects distinctly. The near point of a farsighted eye is farther away than the normal near point (25 cm). } \\ \bullet & \text{Causes: This defect arises due to one of two reasons:} \\ \bullet & \text{The focal length of the eye lens is too long.} \\ \bullet & \text{The eyeball has become too short.} \\ \bullet & \text{Effect: Due to these causes, the light rays from a nearby object are focused at a point behind the retina, not on the retina itself, resulting in a blurred image. } \\ \bullet & \text{Correction: Farsightedness is corrected by using spectacles with a convex lens of a suitable focal length. The convex lens provides the additional converging power required to form the image on the retina. } \\ \end{array}\]