Nature of wave front depends on

Options

A. shape of source
B. distance of source
C. both 1 and 2
D. none of these

Answer

To determine the nature of a wavefront, we need to consider two main factors: the distance of the source and the shape of the source. Let's break this down step by step.

### Step-by-Step Solution:

1. **Understanding Wavefront**: A wavefront is defined as the surface over which an oscillation has a constant phase. In simpler terms, it is the shape that the wave takes as it propagates through space.

2. **Distance of the Source**: The distance of the source from the point of observation significantly influences the nature of the wavefront.
- When the source is very far away (at infinity), the wavefront becomes planar. This is because the waves arrive at the observer from all directions and can be approximated as parallel lines.
- When the source is at a finite distance, the wavefront takes on a different shape.

3. **Shape of the Source**: The shape of the source also plays a crucial role in determining the nature of the wavefront.
- If the source is a point source (like a small light bulb), the wavefront is spherical. This is because waves radiate outwards in all directions from the point source.
- If the source has a rectangular shape, the wavefront becomes cylindrical. This occurs because the waves emanate from the edges of the rectangle and spread out in a cylindrical manner.

4. **Conclusion**: Therefore, the nature of the wavefront depends on:
- The distance of the source (infinity vs. finite distance)
- The shape of the source (point source vs. rectangular source)

### Final Answer:
The nature of the wavefront depends on both the distance of the source and the shape of the source.

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