gen-define-the-law-of-reflection-and-give-one-short-worked-examp-14ed

Define the law of reflection and give one short worked example.

# Law of Reflection ## Definition The **law of reflection** states that when a light ray reflects off a surface: 1. The angle of incidence equals the angle of reflection (θᵢ = θᵣ) 2. The incident ray, reflected ray, and normal (perpendicular to the surface) all lie in the same plane Both angles are measured from the normal to the surface. ## Worked Example **Problem:** A laser beam strikes a flat mirror at an angle of 35° to the normal. At what angle does it reflect? **Solution:** - Angle of incidence: θᵢ = 35° - By the law of reflection: θᵣ = θᵢ - Therefore: θᵣ = 35° **Answer:** The beam reflects at 35° to the normal (on the opposite side). --- *Note: A common mistake is measuring angles from the surface rather than from the normal. If the beam hits at 35° to the normal, it's at 55° to the mirror surface itself.*