Image formed by a Plane Mirror in Different Arrangements

Mirrors play a vital role in our life

From something as routine as seeing ourselves to groom better

To helping us study ray-diagrams due to their simple geometry; plane mirrors are indispensable

Let us see how image formation takes place in plane mirrors

Let us consider an object being placed in front of a plane mirror

An image will be formed by the plane mirror such that the image distance is the same as the object distance

Let's consider the case when the object is placed in front of the mirror

Let us consider the case when object is kept in front of a plane mirror, such that image is produced by the mirror

and are the incident rays; while and are the reflected rays

as well as are the angle of incidence

Whereas, as well as are the respective angle of reflections

We know that according to the Law of Reflection, Angle of Incidence = Angle of Reflection

Therefore, when an incident ray falls on the mirror at a certain angle, it gets reflected back at the same angle

Now in the above figure, we have an extended object , whose image is formed by the plane mirror

As we can see, the height of the image as well as it's a distance from the mirror is similar to that of the object

We can also see that the Image formed is Virtual in nature.

Now let us consider the case in which the object is placed below the mirror

If the object is placed below the mirror, the reflection takes place as shown above

Extending the reflected rays in the backward direction, we get the image at the intersection of two rays

As we can see, the image will be virtual in nature. The image distance will be the same as the object distance from the mirror

Now let us finally consider the case in which the object is placed above the mirror

The reflection and the image formation will happen as shown above

The image distance will be the same as the object distance and it will be virtual in nature

Revision

Plane mirrors are mirrors with flat surfaces

The image formed by a plane mirror is at the same distance from the mirror, as the object

The image height in a plane mirror is the same as the object height. Also, the images formed by these mirrors are always virtual in nature

The End