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In the realm of mirrors, understanding the concept of a virtual image is fundamental. A virtual image is formed when light rays appear to originate from a point behind the mirror, even though they do not actually converge there.

Since plane mirrors reflect light symmetrically, the brain is tricked into reversing the direction of the light rays it sees. This results in an upright and laterally inverted image, meaning left and right are switched. Even though it appears to exist behind the mirror, you cannot actually touch or project it onto a screen, which differentiates a virtual image from a real one.

Key characteristics of a plane mirror's virtual image include:

• Virtual, non-tangible, and non-projectable
• Upright and laterally inverted
• Equal in size to the object creating it
• Appearing to be the same distance behind the mirror as the object is in front

These qualities make virtual images fascinating and a bit like optical illusions. Hence, when the man stands 1.5 meters from the mirror, his virtual image is also perceived to be 1.5 meters behind the mirror.

The formation of images in mirrors, especially plane mirrors, is bound by certain well-established properties. These properties dictate how we perceive objects and images in mirrors.

The main properties of image formation in plane mirrors are:

• **Equal Distance:** The distance at which the image appears behind the mirror is precisely the same as the distance of the object in front of it.
• **Size Consistency:** The size of the image is the same as that of the object. Plane mirrors do not distort the object's dimensions.
• **Upright Orientation:** The image is the correct way up. Although it is laterally inverted, it remains upright.
• **Virtual Image:** As discussed earlier, the image appears to be located behind the mirror and cannot be projected onto a screen.

These properties are intrinsic to plane mirrors and help explain why, when you stand 1.5 meters away from a mirror, your image seems to be exactly the same size and distance behind the mirror.

The geometry of a plane mirror plays a crucial role in image formation. A plane mirror has a flat reflective surface, making it different from curved mirrors like convex or concave varieties. This flat geometry ensures that reflection follows an important rule known as the law of reflection.

The law states:

• The angle of incidence (the angle at which the incoming ray strikes the mirror) is equal to the angle of reflection (the angle at which the ray bounces off).

This principle implies that all light rays striking the mirror will reflect at angles that mirror the incoming paths perfectly, creating a symmetrical image.

For our exercise, understanding mirror geometry helps to appreciate why the virtual image appears as it does. The man's image is 1.5 meters behind the mirror, and this distance comes simply from the reflective nature of a plane mirror. Every part of his image is formed in such a way that the simple geometry of light incident on a flat surface remains consistent throughout, maintaining image size and orientation.