Question

Why does a straight rod appear bent in water?
A. Due to reflection of light
B. Due to refraction of light
C. Due to variable refractive index of water
D. None of the above

Answer 1

Hint: The above problem can be resolved using the concepts and fundamentals of the refraction of light rays while entering from one medium to another medium. In this problem, the reason for the visualisation for the bending of the rod is asked. The major reason behind the happening is due to shifting of apparent position due to refraction.

Complete step by step answer:
It is a common observation that the straight rod is usually occurring in the bent form when one continuously observes the vessel containing the water and rod. The primary reason for this is the phenomenon of refraction of light rays. When the rod is dipped inside the vessel, containing some amount of water, then, at that moment we transfer the rod from rarer medium to much denser medium. Along with this, the ray of light also gets transferred from the rare medium to denser medium, after crossing interface, the light ray will be bent towards normal. Now due to this bending of the light ray, the lower part of the rod will appear to be bent in water, and shifting of the apparent position of rod in water also takes place.
Therefore, the straight rod appears bent in water due to refraction of light.

So, the correct answer is “Option B”.

Note:
Try to understand the concept of refraction and also try to know how this happens? The basic fundamental is that when the light ray enters, such that it enters from rare to a denser medium, then the bending is towards the normal and vice versa.