Practice MCQ Questions and answers on Physics-GK

A mirage occurs because of total internal reflection by layers of air.

Optical fibers operate based on the principle of total internal reflection phenomenon that occurs at the interface between the core and the cladding provided that the angle of the incident light inside the core is higher than the angle called critical angle.

The normal line divides the angle between the incident ray and the reflected ray into two equal angles. The angle between the incident ray and the normal is known as the angle of incidence. The angle between the reflected ray and the normal is known as the angle of reflection.

A periscope works by the principle of total internal reflection.

Total internal reflection will not take place unless the incident light is traveling within the more optically dense medium towards the less optically dense medium. Total internal reflection can not take place when light goes from water to glass.

Type of mirror used in the rear-view mirror must be convex mirrors, because it creates smaller, yet still upright images. Concave mirrors would create an inverted image and the cars you see are not upside down.

Concave mirrors are used in search lights and torches so that we have a more focused light beam which will not diverge out and hence help in searching. It is used for different light rays falling on it to a single point.

The optical fibre is a device which works on the principle of total internal reflection by which light signals can be transmitted from one place to another with a negligible loss of energy.

Mirage is formed due to both Refraction and Total internal reflection of light. A mirage is a naturally occurring optical phenomenon in which light rays bend to produce a displaced image of distant objects or the sky.