Reflection of waves
Vibrations that transfer energy from place to place without the transference of matter. - 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°, it will be reflected at 32°.
The Angle between the normal and the incident ray. and The 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 An 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° to the surface. The diagrams show a water wave being reflected at a barrier, and a light ray being reflected at a A flat, two-dimensional surface. mirror.
Specular reflection
Reflection from a smooth, flat surface is called Reflection in which light travelling towards a surface in one direction is all reflected in a single direction.. This is the type of reflection that happens with a flat mirror. The image in a mirror is:
- upright
- virtual
In a An image from which rays of light appear to come but do not do so in reality., the rays appear to diverge from behind the mirror, so the image appears to come from behind the mirror.
Diffuse reflection
If a surface is rough, When light is reflected off a surface and is scattered in different directions. happens. Instead of forming an image, the reflected light is scattered in all directions. This may cause a distorted image of the object, as occurs with rippling water, or no image at all. Each individual reflection still obeys the law of reflection, but the different parts of the rough surface are at different angles.