Final answer:
In a plane mirror, the angle of incidence is equal to the angle of reflection, as dictated by the law of reflection.
Step-by-step explanation:
In a plane mirror, the angle of incidence is equal to the angle of reflection. This is a fundamental concept described by the law of reflection, which states that the incident ray, the reflected ray, and the normal to the mirror at the point of incidence all lie in the same plane. Additionally, both the angle of incidence and the angle of reflection are measured relative to the normal, which is the line perpendicular to the surface at the point where the ray strikes the mirror.
The law of reflection can be simply stated as: If the angle of incidence is represented as θ₁, then according to the law, the angle of reflection will be the same (θ₁ = θ’). This principle is not only applicable to plane mirrors but is a general property of light when it reflects off any smooth surface.