Question

State two uses of regular reflection.

Answer 1

Hint: Here, we will proceed by defining the term regular reflection. Then, we will write down two important uses of regular reflection. Then, in the additional information we will discuss irregular reflection.

Complete step-by-step answer:

Regular reflection is the reflection of light rays as they meet (fall on) a smooth (uniform) and glittering surface, where the incident light rays are reflected in one direction. If a beam of parallel light rays happens on a smooth and plane surface, the reflected rays will also be parallel, and it is called regular reflection.

Two uses of regular reflection are as given under:

$1.$ Because of the regular reflection, we are able to see our image in the plane mirror when we are facing it.

$2.$ A periscope is an optical device that displays images through a tube using a series of prisms, lenses, or mirrors. Light from a distant source hits the top mirror and is then mirrored down the periscope tube at an angle of 90 degrees. The light hits another mirror at the bottom of the periscope, and is then reflected in the eye of the spectator. Contrary to the periscopes used on submarines which are typically a complicated optical device utilizing both lenses and mirrors, this basic periscope uses only flat mirrors. Due to regular reflection, formation of images in periscope is possible.

Additional information:
Irregular reflection is the reflection of light rays as they encounter (fall on) a rough (non-uniform) reflecting surface, where light ray incident is reflected in various directions.

As a beam of parallel light rays is dispersed in all directions, it can reflect in different directions the parallel ray incident on the surface and it is called irregular or diffuse reflection.

Irregular reflection or diffuse reflection occurs when light rays occur on a surface such as a wall, a wood, a tree leaf, a piece of leather, a piece of paper or a piece of wool that is not smooth or polished, so that the various parts of the surface reflect incident light ray indifferent directions.

There is no definite picture produced, but the surface is visible, it is generally known as light dispersal, and diffused reflection makes visible non-luminous objects.

Note: In order to write the solution to this problem, one must know that regular reflection happens when the light rays occur on a polished smooth surface such as a plane mirror, a sheet of stainless steel and a thin sheet of aluminium, and the reflected light rays only travel in a fixed direction.