On decreasing the distance between two slits, the fringe width will ………………. .

Explanation

To solve the question regarding the effect of decreasing the distance between two slits on fringe width, we can follow these steps:

### Step-by-Step Solution:

1. **Understanding the Setup**:
- In Young's Double Slit Experiment (YDSE), we have two slits (S1 and S2) separated by a distance \( d \).
- The distance from the slits to the screen where the interference pattern is observed is denoted by \( D \).
- The wavelength of the light used is denoted by \( \lambda \).
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