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  Student Engineer  


Wave Properties - Reflections

Waves can reflect off various surfaces, when they reflect they obey the law of reflection. That is that the angle of incidence equals the angle of reflection.
The easiest wave to demonstrate this would be a light wave reflecting off a mirror. The image below shows the incidence ray which is the ray that travels towards the mirror and reflected ray which as the name suggests is the ray that is comes off of the mirror.


Law of reflection

If the reflecting surface is very smooth, the reflection of light that occurs is called specular or regular reflection.
The angle of incidence is the angle between the incidence ray and the normal while the angle of reflection is the angle between the reflected ray and the normal.
The normal is a line which we draw perpendicular to the reflective surface point where the incidence ray hits it.
To summarise the laws of reflection are as follows:

  1. The incident ray, the reflected ray, and the normal to the surface at the point of incidence all lie in the same plane.
  2. The angle which the incident ray makes is equal to the angle of reflection.
  3. The reflected ray and the incident ray are on the opposite sides of the normal.

In a reflection the object will be the:
The same size
The same distance behind the reflective surface as the real object is in front
The left and right will appear mirrored © 2016