Reflection Cases With Plain Mirror

Description:

Let us consider an object for example a human being standing in front of a plane mirror. The incident ray coming from the foot and the head of the person is reflected by the mirror and reaches the eyes of the person as shown in the figure.

To form an image, we trace the reflected ray backwards to a length ‘l’ (same as the length traveled by the incident ray) which gives us the apparent location of the foot ‘F dash’ and head ‘H dash’.

For the image we can observe four characteristics −

Location of image

Image formed by plane mirror is located on the opposite side of the mirror.

Size of image

Size of the image is same as the size of the object.

Nature of image

Image formed is virtual in nature.

Note − There are two natures of image

Real image

Real image is made by actual intersection of rays before entering the eyes.

Real image can be taken on screen.

Virtual image

Virtual image does not exist but appears only at the point of intersection of extended line of ray.

Virtual image cannot be taken on screen.

Orientation of image

Image is Erect.

• In order to see the full image of a person a mirror of at least half the height of observer is required.
• Lateral inversion occurs in plane mirror.