Ray Optics and Optical Instrument - Reversibility of Light
Law of Reversibility: When the ray of light reverse back to its own path after refraction and reflection, this phenomenon is called Reversibility.
Multiply both equation.
1n2 X 2n1 = 1
When the light ray passes though multi medium
At 1st Interface
At 2nd Interface
At 3rd interface
Multiplying equation (i), (ii) & (iii)
If C is very close to A, then OC = OA = real and IC = IA = Apparent
2n1 = Apparent Depth / Real Depth
apparent depth = n X real depth
Change in depth = real depth – apparent depth
Shift in depth = OA - 2n1 X OR
= OA (1 - 2n1)