Question

Define regular and irregular reflection.

Answer 1

Regular reflection-
For a parallel incident beam of light, if the reflected beam is also parallel, the reflection is called as regular reflection.
Regular reflection takes place from shiny, smooth surfaces like glass and polished metal surfaces.

Irregular reflection-
For a parallel incident beam of light, if the reflected beam is not parallel, then reflection is called as irregular reflection.
Such reflection takes place from rough surfaces like bricks, and paper.