Question

A convex mirror is used as rear-view mirror in automobiles as it covers area behind the driver
(A). Wide
(B). Narrow
(C). Neither A or B
(D). Very narrow

Answer 1

Hint: Recall the basic laws of reflection and the rules of drawing the ray diagram. Draw the ray diagram for an object and compare the location of the object in a convex mirror and a plane mirror.

Complete step by step answer:
A convex mirror or diverging mirror is a curved mirror in which the reflective surface bulges towards the light source. Convex mirrors reflect light outwards, therefore they are not used to focus light.
Such mirrors always form a virtual image, since the focal point and the centre of curvature are both imaginary points inside the mirror that cannot be reached. So, the images formed by these mirrors cannot be projected on a screen, since the image formed will always lie inside the mirror. The image is smaller than the object, but gets larger as the object approaches the mirror.
The image formed by a plane mirror is farther from the horizontal axis compared to the image formed by the convex mirror, which means that convex mirrors can accommodate a wider range than a plane mirror. This can be observed from the ray diagram in the figure.

The side mirror on a car is typically a convex mirror. Convex mirrors are preferred in vehicles because they give an inverted image and because they provide a wider field of view as they are curved outwards.

Note: Another way to arrive at the answer is to give a thought on what features would be desired if a mirror is installed in a car. And what purpose would it solve? The obvious answer would be to have a wider view. Because no one would want a narrower or obstructed view while driving.