Our topic for today is Laws of Reflection.
Consider this ray of light which strikes a mirror.
This ray of light is called the incident ray.
The point at which the incident ray strikes the mirror is called point of incidence.
Draw a line perpendicular to the mirror through the point of incidence.
This line is called Normal.
The angle which the incident ray makes with the normal is called the angle of incidence.
When this ray strikes the mirror, it will bounce off the mirror.
This ray which bounces off is called the reflected ray.
The angle which the reflected ray makes with the normal is called angle of reflection.
Now, let us study the 2 laws of reflection.
The angle of incidence is always equal to the angle of reflection.
If the angle of incidence is 30 degrees, then the angle of reflection will also be 30 degrees.
Remember that, these angles are always measured from the normal, not from the mirror.
The incident ray, the normal at the point of incidence and the reflected ray, all lie in the same plane.
17 дек 2015
