Question

In the List-I, four optical effects are mentioned. The physical phenomena of light which are essential to describe these optical effects are given in List-II. Choose the option which describes the correct match between the entries in List-I to those in List-II. {p{7cm} p{6cm}} List-I & List-II
(P) Colorful sky in north polar region (Aurora Borealis) & (1) Dispersion and reflection
(Q) Partially polarized sunlight & (2) Total internal reflection
(R) Rainbow & (3) Diffraction
(S) Dark and bright fringes & (4) Scattering of light by molecules in the atmosphere
& (5) Emission of radiation from oxygen and nitrogen atoms excited by charged particles

• A. \(P \to 5,\ Q \to 4,\ R \to 1,\ S \to 3\)
• B. \(P \to 4,\ Q \to 2,\ R \to 1,\ S \to 3\)
• C. \(P \to 4,\ Q \to 1,\ R \to 2,\ S \to 3\)
• D. \(P \to 5,\ Q \to 4,\ R \to 1,\ S \to 2\)

Hint:

Aurora Borealis: \[ \text{Emission from excited atmospheric atoms} \] Rainbow: \[ \text{Dispersion + internal reflection} \] Fringes: \[ \text{Interference/Diffraction} \]

Answer 1

The Correct Option is A

Step 1: Match Aurora Borealis.
Aurora Borealis occurs due to: \[ \text{excitation of oxygen and nitrogen atoms} \] by charged particles from the Sun. Thus: \[ P\to5 \]

Step 2: Match partially polarized sunlight.
Partially polarized sunlight is produced due to: \[ \text{scattering by atmospheric molecules} \] Thus: \[ Q\to4 \]

Step 3: Match rainbow.
Rainbow formation involves: \[ \text{dispersion and internal reflection} \] Thus: \[ R\to1 \]

Step 4: Match dark and bright fringes.
Dark and bright fringes arise due to: \[ \text{diffraction/interference effects} \] Thus: \[ S\to3 \]

Step 5: Final matching.
\[ P\to5,\qquad Q\to4,\qquad R\to1,\qquad S\to3 \] Hence correct option is: \[ \boxed{\mathrm{(A)}} \]