Question

The formation of mirage is due to :
A.)Reflection
B.)Refraction
C.)Dispersion
D.)Total internal reflection

Answer 1

Hint: Generally mirages happen when the air is cool and the ground is very hot. The hot ground warms the layer of air that is just above the ground. And when the light passes the layer of cold air and then gets into the layer of hot air the light rays get refracted (bent).

Complete answer:
A mirage in simple words is just an optical illusion caused by atmospheric conditions, in which light rays bend via refraction to produce an image of a distant object in the sky or atmosphere.
Total internal reflection is the phenomenon due to which a light ray reflects totally inside a medium.
The formation of mirage is due to the total internal reflection of light.

So, the correct answer is “Option D”.

Additional Information:
Conditions for total internal reflection are:

a.)The light ray moves from a denser medium to a less dense medium.
b.)The angle of incidence must always be greater than the critical angle.

Refraction is the phenomenon due to which light rays get deviated or changes direction when passes from one medium to another, it generally happens because we know that the speed of the light in two different medium is not the same, hence the speed of light changes and due to this sudden change in the velocity of the light, the light rays tend to move towards or away from the normal. The movement of the light ray towards or away from the normal totally depends on the velocity of the light if it increases then it goes away from the normal and if it decreases it comes towards the normal.

Note:
Total internal reflection is the phenomenon due to which complete reflection of a ray of light within a medium takes place, it is generally seen in mediums like water or glass. The phenomenon of total internal reflection happens when the incident angle is greater than the critical angle.