Two coherent sources are `0.15` mm apart and fringes are observed 1m away with monochromatic light of wavelength `6000^(0)`. Find
The fringe width in air.

Explanation

To find the fringe width in air for the given problem, we can follow these steps:

### Step 1: Understand the parameters given in the problem
- Distance between the two coherent sources (slits), \( d = 0.15 \, \text{mm} = 0.15 \times 10^{-3} \, \text{m} \)
- Distance from the sources to the screen, \( D = 1 \, \text{m} \)
- Wavelength of the monochromatic light, \( \lambda = 6000 \, \text{angstrom} = 6000 \times 10^{-10} \, \text{m} = 6 \times 10^{-7} \, \text{m} \)

### Step 2: Use the formula for fringe width
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