List - I List -II
a) spherical wave front e) location of new wave front
b) plane wave front f) line source
c) cylindrical wave front g) point source at finite distance
d) Huygen's principle h) point source at infinite distance

Options

A. `A-G, B-H, C-F, D-E`
B. `A-H, B-G, C-F, D-E`
C. `A-H, B-G, C-E, D-F`
D. `A-H, B-G, C-F, D-E`

Answer

To solve the matching question between List I and List II, we will analyze each item in List I and find its corresponding match in List II based on the principles of wave optics.

### Step-by-Step Solution:

1. **Identify Spherical Wave Front (a)**:
- A spherical wave front is produced by a point source at a finite distance. As the waves propagate from the source, they form concentric spherical surfaces.
- **Match**: a) Spherical wave front → g) Point source at finite distance.

2. **Identify Plane Wave Front (b)**:
- A plane wave front is typically produced by a point source that is very far away (at infinite distance). The waves arrive parallel to each other, creating a flat wave front.
- **Match**: b) Plane wave front → h) Point source at infinite distance.

3. **Identify Cylindrical Wave Front (c)**:
- A cylindrical wave front is generated by a line source. The waves spread out in cylindrical shapes from the line source.
- **Match**: c) Cylindrical wave front → f) Line source.

4. **Identify Huygen's Principle (d)**:
- Huygen's principle states that every point on a wave front can be considered a source of secondary wavelets, and the new wave front is formed by the envelope of these wavelets.
- **Match**: d) Huygen's principle → e) Location of new wave front.

### Final Matches:
- a) Spherical wave front → g) Point source at finite distance
- b) Plane wave front → h) Point source at infinite distance
- c) Cylindrical wave front → f) Line source
- d) Huygen's principle → e) Location of new wave front

### Summary of Matches:
- a → g
- b → h
- c → f
- d → e