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==== Law of Reflection ====
When light propagates to the interface between two different media, a portion of the light returns to the original medium. This phenomenon is known as the reflection of light. The reflection of light follows these laws:
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  * The incident ray, the reflected ray, and the normal all lie in the same plane.
  * The reflected ray and the incident ray are on opposite sides of the normal.
  * The angle of reflection is equal to the angle of incidence (\(\theta _{r}=\theta _{i}\)).
Here, the normal is an imaginary line perpendicular to the interface, and both the angle of incidence and the angle of reflection are measured between the respective rays and the normal.

**Image Formation by a Plane Mirror**\\
When we look into a mirror, the image we see is a direct result of the law of reflection.
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Every point on an object emits light rays in all directions. When these rays strike a smooth mirror surface, they are reflected according to the law of reflection, and the resulting virtual image points together form the complete virtual image of the object.