What is the effect on the interference fringes in a Young.s double-slit experimental due to each of the following operations :
The width of the source slit is increased.

Explanation

### Step-by-Step Solution:

1. **Understanding Young's Double-Slit Experiment**:
- In Young's double-slit experiment, two slits (A and B) are illuminated by a coherent light source, creating an interference pattern on a screen. The distance between the slits is denoted as \(d\), the distance from the slits to the screen is \(D\), and the width of each slit is \(s\).

2. **Condition for Interference Pattern**:
- The interference pattern is observed when the light waves from the two slits overlap and interfere with each other. For a clear interference pattern to appear, the following condition must be satisfied:
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