Question

Distinguish between

(1) Myopia and Hypermetropia

(2) Convex mirror and concave mirror

Answer 1

(1) Difference between myopia and hypermetropia:

Myopia	Hypermetropia
Myopia or nearsightedness is a condition in which objects in the distance appear blurred. A person can see nearby objects clearly, but not distant objects.	Hypermetropia or long sightedness is a defect of vision caused by an imperfection in the eye causing difficulty in focusing on nearby objects.
This defect may arise due to excessive curvature of the eye lens or elongation of the eye ball.	This defect arises often when the eyeball is too short or the lens cannot become round enough.
To correct this defect of vision, a concave lens is used which has the ability to diverge incoming rays on the retina.	To correct this defect of vision, a convex lens is used which has the ability to converge incoming rays for forming the image on the retina.

(2) Difference between convex mirror and concave mirror:

Convex mirror	Concave mirror
The reflecting surface of the convex mirror is bulged outwards.	The reflecting surface of the concave mirror is bulged inwards.
The convex mirror always produces virtual and erect images.	The concave mirror produces real and inverted images (except when the object is placed between pole and focus. When the object is placed between F and P, concave mirror produces virtual and erect image).
The image formed by the convex mirror will be always diminished.	The image formed by the concave mirror may be enlarged or diminished, according to the position of the object.