waveSomething that can transfer energy. - including sound and light - can be reflected at the boundary between two different materials. The reflection of sound causes echoes.
The law of reflection states that:
angle of incidence = angle of reflection
For example, if a light ray hits a surface at 32掳, it will be reflected at 32掳.
The angle of incidenceAngle between the normal and the incident ray. and angle of reflectionThe angle between the reflected ray and the normal (the imaginary line drawn at 90 degrees to the reflecting surface). are measured between the light ray and the normalAn imaginary but useful line at right angles to the boundary between air/glass. All angles are measured to this line. - an imaginary line at 90掳 to the surface. The diagrams show a light ray being reflected at a planeA flat, two-dimensional surface. mirror.