4. Types of reflection

Depending on the surface on which light hits, the reflection is classified into two types

Regular reflection:

 

In the above image, the reflecting surface is very smooth; so when parallel rays of light fall on it, it will reflect as parallel rays by obeying the laws of reflection. If the reflecting surface is smooth or regular, then we have a specular or regular reflection.

 

In the above image, the reflecting surface is very rough, so when parallel rays of light fall on it, it will reflect at different angles by obeying law of reflection. Thus, the reflected rays are not the same as incident rays. If the reflecting surface is not smooth or rough, then we have diffused or irregular reflection.

 

 

The mirror has a smooth surface in the above image, so regular or specular reflection occurs when light rays fall on it. Cracked land has a rough surface, so irregular or diffused reflection occurs when light rays fall on it.

 

When we switch on a bulb in a dark room, light spreads the whole room quickly. This is because the speed of the light. Light travels three lakh kilometres per second in air or vacuum. Nothing can travel faster than light. Speed of light is denoted by the letter '\(c\)'

Speed of light (\(c\))= $3\times {10}^8$\(m/s\)