If the principal source point S was to be moved a little upwards, towards the slit `S_(1)` from its usual symmetrical position with respect to the two slits `S_(1)andS_(2)` discuss how the interference pattern, obtained on the screen, would get affected.

Explanation

To analyze how the interference pattern is affected when the principal source point S is moved upwards towards slit S1, we can follow these steps:

### Step-by-Step Solution:

1. **Understand the Initial Setup**:
- We have two slits, S1 and S2, which are equidistant from a central source point S. The screen is placed at a distance where the interference pattern is observed.

2. **Identify the Shift in Source Position**:
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