Match List-I with List-II (here symbols have their usual meanings)
| List-I | List-II |
| Physical Quantity / Law | Formula |
| (A) Snell's law | (I) \( \frac{t}{\mu} \) |
| (B) Apparent Shift | (II) \( \frac{c}{v} \) |
| (C) Refractive Index | (III) \( \frac{\mu_2}{\mu_1} \) |
| (D) Apparent depth | (IV) \( t\left(1-\frac{1}{\mu}\right) \) |
Choose the correct answer from the options given below:
Answer & explanation
Correct answer: option 3
The correct answer is Option (3) → (A) - (III), (B) - (IV), (C) - (II), (D) - (I)
For refraction at a plane surface, \( t \) is the real depth (or thickness of the slab) and \( \mu \) the refractive index of the denser medium relative to air.
(A) Snell's law — this matches (III) \( \frac{\mu_2}{\mu_1} \). Snell's law gives the ratio of the sines of the angles as the relative refractive index.
\( \displaystyle \frac{\sin i}{\sin r} = \frac{\mu_2}{\mu_1} \)
(B) Apparent Shift — this matches (IV) \( t\left(1-\frac{1}{\mu}\right) \). The shift is the real depth minus the apparent depth, \( t - t/\mu \).
(C) Refractive Index — this matches (II) \( \frac{c}{v} \). The absolute refractive index is the speed of light in vacuum divided by its speed in the medium.
(D) Apparent depth — this matches (I) \( \frac{t}{\mu} \). Seen from above at near-normal incidence, an object at real depth \( t \) appears raised to the depth \( t/\mu \).