Which statement defines the angle of incidence in reflection?

Which statement defines the angle of incidence in reflection?

• A. The angle between the incident ray and the normal line.
• B. The angle between the incident ray and the surface.
• C. The angle between the reflected ray and the normal line.
• D. The angle between the reflected ray and the surface.

Answer: (A)

The angle of incidence is the angle formed between the incoming light ray and the normal line to the surface at the point where the light hits. The normal is a line drawn perpendicular to the surface. This way of measuring uses the normal because the law of reflection states that the angle of incidence equals the angle of reflection, and both are measured with respect to the normal. The angle between the incident ray and the surface would be the complement of the incidence angle, not the standard measure. The angle between the reflected ray and the normal is the angle of reflection, not the incidence. So the statement describing the angle between the incoming ray and the normal is the correct one.

The angle of incidence is the angle formed between the incoming light ray and the normal line to the surface at the point where the light hits. The normal is a line drawn perpendicular to the surface. This way of measuring uses the normal because the law of reflection states that the angle of incidence equals the angle of reflection, and both are measured with respect to the normal. The angle between the incident ray and the surface would be the complement of the incidence angle, not the standard measure. The angle between the reflected ray and the normal is the angle of reflection, not the incidence. So the statement describing the angle between the incoming ray and the normal is the correct one.