Question

explain any 2 defects of vision

Answer 1

heya mate, happy new year ^_^

Defects of the eye: Myopia: (nearsightedness) This is a defect of vision in which far objects appear blurred but near objects are seen clearly. The image is focused in front of the retina rather than on it usually because the eyeball is too long or the refractive power of the eye's lens too strong.

hope it helps : )

Answer 2

$\large\bf{\underline{Here\: is\: your \:answer:-}}$

$\sf{\underline{The\: main\: defects \:of\: vision\:are:-}}$

✔️ Myopia.
✔️ Hypermetropia.
✔️ Presbyopia.

$\bf{\large{Myopia}}$

Myopia is also known as near-sightedness. A person with Myopia can see nearby objects clearly but cannot see distant objects distinctly.

This defect arises due to :-
⏩ Excessive curvature of the eye lens.
⏩ Elongation of the eyeball.

This defect can be corrected by using a concave lens of suitable power.

$\bf{\large{Hypermetropia}}$

Hypermetropia is also known as far-sightedness. A person with hypermetropia can see distant objects clearly but cannot see near by object distinctly.

This defect arises due to:-
⏩ The focal length of the eye lens is too long.
⏩ The eyeball has become too small.

This defect can be corrected by using a convex lens of appropriate power.

$\bf{\large{Presbyopia}}$

The power of accommodation of eyes usually decreases with ageing. They find it difficult to see nearby objects comfortably and distinctly without corrective eye-glasses. This defect is called Presbyopia.

This defect arises due to:-
⏩ Gradual weakening of ciliary muscles.
⏩ Diminishing flexibility of the eye lens.

This defect can corrected by using bi-focal lenses consists of both concave and convex lenses.

$\huge\mathfrak\red{Hope\:it \:helps\: you}$