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What is the Principle of Reversibility?a)If the final path of a ray of light is reversed after any number of reflections and refractions, then the ray retraces its entire path.b)If the final path of a ray of light is reversed after any number of refractions only, then the ray retraces its entire path.c)If the final path of a ray of light is reversed after any number of reflections and refractions, then the ray retraces half of its path.d)If the initial path of a ray of light is reversed after any number of reflections only, then the ray retraces its entire path.Correct answer is option 'A'. Can you explain this answer? Related Test: Test: Refraction By Plane Surfaces

Class 12 Question

By Santosh Tamang · 2 days ago ·Class 12
Harsha Vardhanag answered Mar 30, 2020

Jyotsna Gupta answered Sep 03, 2018
The principle of reversibility of light :-
If the path of light is reversed after a number for reflections and refraction then it retraces it's path.
Note the directions of the arrow.
The beam of light travels back on the same path as it was traveling before the refraction and after the refraction after being encountered by the obstacle in the water.