A thin air film is between two points A and B. When light of wavelength `5400 Å` is used, 5 fringes appear between the two points. Find the difference in the thickness of the film between the two points.

Explanation

To solve the problem of finding the difference in thickness of a thin air film between two points A and B, we can follow these steps:

### Step-by-Step Solution:

1. **Understanding the Problem**: We have a thin air film between two points A and B, and when light of wavelength \( \lambda = 5400 \, \text{Å} \) (angstroms) is used, 5 fringes appear. We need to find the difference in thickness of the film between these two points.

2. **Formula for Thin Film Interference**: For constructive interference in thin films, the condition is given by:
\[
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