Plane mirrors are the most common mirrors found in our day to day life. For a person not so familiar with term, a plane mirror is any normal mirror found in homes and offices, dressing rooms and tables that are coated with mercury on one of its side to enable reflection of light and formation of image.
IMAGE FORMATION by a plane mirror –
To observe the formation of an image by a plane mirror, the person should be in line of sight of the mirror so as the rays reflected by the plane mirror can reach the person’s eyes and thus he is able to view the image.
CHARACTERISTICS of the image formed by a plane mirror –
· The image formed is upright or erect
· It is virtual
· It is of the same size as that of the object
· Its magnification is 1
Magnification is the process of enlarging the apparent size of an object, and not the physical size. And thus, it is a measurable quantity. It can also be referred to as the ratio of the size of image to the size of object. It is denoted by the letter ‘m’ .
Magnification (m) = height or size of image (h’) / height or size of object (h)
Also, it can calculated using the image – object distance :-
Magnification (m) = -image distance (v) / object distance (u)
MAGNIFICATION OF A PLANE MIRROR
A plane mirror forms a virtual, erect image. The image is of the same size as that of the object. Also, it is formed at equal distance, that is, the image distance (v) is equal to the object distance (u). thus, the magnifivation by a plane mirror equals 1.
M = -v / u = 1
M = h’ / h = 1
Thus, plane mirror gives a magnification of 1.
I hope this answer helps.