Reflection of light is described along with reflection definition, its laws, and examples. There are many terms like the angle of incidence, incident rays, reflected rays, etc. are well explained for easy understanding.
What is Reflection of Light?
When we stand in front of the mirror, we see our face and comb hair. But do you why we are able to see ourselves in the mirror? It is simply because of the reflection of light. Let us try to understand reflection!
When a light ray falls on a polished, smooth & shiny surface, it bounces back. This phenomenon is known as the reflection of light.
The smooth & shiny surface can be:
- Stable Water surface
- Shiny Metals
- or any others
If a light ray falls on an object, there may be three options:
- Light can be passed through
- Light can be absorbed
- Light can be bouncing back in the same medium.
Lets, take a torch and a mirror. If we switched on light and fall the light rays on the mirror, we see the reflected rays on the wall.
This is known as reflection.
Check out our ANIMATED video!
The surface on which light rays fall is called a reflective surface. The light ray which falls on the surface is called an incident ray and which bouncing back or reflected is known as a reflected ray. The point at which incident ray falls is known as the point of incidence. Reflected ray bouncing back in the same medium here it is air.
If a perpendicular line to be drawn on the surface, it would be called normal. The angle between the incident ray and normal is the angle of incidence and the angle between the reflected ray and normal is known as the angle of reflection. The below image shows the reflection of light on a plane mirror.
The surface on which light falls
The light which falls on the surface
Point of incidence
The point where incident ray falls on the surface
The light which bouncing back
Angle of incidence
The angle between the incident ray and normal (Denoted as ‘i’)
Angle of reflection
The angle between the reflected ray and normal (Denoted as ‘r’)
Diagram of Reflection of Light
Here, all the rays, angle of incidence (i), angle of reflection (r) are well captured for better understanding:
In a 3D view, it will be like. As follows:
Laws of Reflection
When reflection happens on reflecting surfaces, like mirrors, smooth metal surfaces, and clear stable water or any other same kind of surfaces, there will be two principles which are known as lows of reflection.
Let’s consider a plane mirror as shown in the image above. The law of reflection shall be, as follows:
Rule#1 Laws of Reflection
The angle of incidence = Angle of reflection
Rule#2 Laws of Reflection
The incident ray, the reflected ray and the normal all lie in the same plane.
Type of Reflection
Reflection of light is of three types,
- Regular / specular / uniform reflection
- Diffused reflection
- Multiple reflections
Regular / specular / uniform reflection
The regular reflection or specular reflection is a type of reflection when light rays fall on a very smooth surface and reflected in one direction.
- Incident rays are parallel and uniform
- Reflected rays are parallel and uniform
- The reflected surface is smooth and shiny
- Reflection happens uniformly and almost all the incident lights got reflected.
Reflection on the mirror is an example of regular or specular or uniform reflection.
The diffused reflection is another type of reflection when light rays fall on a rough surface, and reflected rays are haphazard instead of uniform.
- Reflected rays are not parallel, basically haphazard
- The reflected surface is rough
- If the reflected surface has dents, or darts, or wear and tear, diffused reflections are created.
Due to diffused reflection, we are able to see movies in the cinema halls.
Multiple reflections mean multiple numbers of reflections. If regular reflection, we see only one image of one object for the reflection on a mirror. Now, what about if we keep one more mirror? You will see multiple numbers of images. You can keep a few more mirrors to check it more preciously.
- In these multiple reflections, the light source from one object reflected multiple times.
- Multiple numbers of images are formed.
- The numbers of images depend on the angle between mirrors.
Hence, we have learned the basics of reflection of light, laws, etc. Any questions, please write to us.