Question

A full-length image of a distant tall building can definitely be seen by using?
A) A Concave mirror
B) A Convex mirror
C) A Plane mirror
D) Both concaves as well as a plane mirror

Answer 1

Hint: As we know the image formed by a convex mirror is diminished and virtual and the image formed by a concave mirror is real inverted and extremely diminished in size when the object is far away from the mirror and the plane mirror makes an image of similar size as an object from this hint you can get the answer.

Complete step by step answer:
As we know the image formed by a convex mirror is always smaller than object size and it makes an erect and virtual image of the object. It is also called a diverging mirror. It covers a wide area behind the mirror so it is also used as a rear view mirror in vehicles.
To understand is clearly take a look at the below figure:

When a tall building AB at a distance from the mirror then A ray of light AD running parallel to the principal axis gets reflected along DX. If extended backward, DX seems to originate from F. Another ray AE which goes towards the center of curvature (C) is reflected back along EA. These two diverging rays DX and EA, when produced back, appear to intersect at B’. So, the image of the building formed is behind the mirror, virtual, erect, and diminished.
So the full-length image of the distant tall building can definitely be seen by using a convex mirror.

Here option A is correct.

Note:
A plane mirror can do the same but for that height of the mirror will have to be at least equal to the height of the object.
A concave mirror forms a magnified image when the object is placed near the pole if the object placed away from the mirror the image formed by a concave mirror is point size at the focus.
But a convex mirror easily formed a full-length image of any object.