Question

What is the reason for the shiny air bubble in the water?

A) Reflection
B) Refraction
C) Diffraction
D) Total internal reflection

Answer 1

Hint: The air bubble can be well defined as the sphere with the convex surface and when light reaches it, the light is reflected within the water as in the concave lens. The air bubble in the water shines due to the phenomenon of total internal reflection. 

Complete answer:

In physics, the total internal reflection is defined as the ray of light within the medium such as water or glass from the surrounding surfaces back into the medium.The total internal reflection is well defined as the phenomenon that occurs when the light rays travel from a more optically denser medium to the less optically denser medium. Also, during the phenomenon the angle of incidence must be greater than the critical angle.The air bubble shines since the speed of light is faster inside the air bubble than in the water and therefore the light gets reflected away from the bubble around just like the mirror. This happens only along the circle in the direction we observe it. Also, if we observe towards the center of the bubble, we can see completely through it. 

Hence, air bubbles shine due to the phenomenon of the total internal reflection.

The correct answer is option D.

Note:

Know the difference between the reflection and refraction of light. The reflection of light can be expressed as the change in the direction of the wave-front between the two different medium whereas refraction of light can be expressed as the bending of light when it passes from one transparent substance into another.