In Young's double slit experiment separation between slits is 1mm, distance of screen from slits is 2m. If wavelength of incident light is 500 nm. Determine
(i) fringe width
(ii) angular fringe width
(iii) distance between 4 th bright fringe and 3rd dark fringe
(iv) If whole arrangement is immersed in water `(mu_(w)=4//3)`, new angular fringe width.

Explanation

To solve the given problem step by step, we will break it down according to the parts of the question.

### Given Data:
- Separation between slits, \( d = 1 \, \text{mm} = 1 \times 10^{-3} \, \text{m} \)
- Distance from slits to screen, \( D = 2 \, \text{m} \)
- Wavelength of light, \( \lambda = 500 \, \text{nm} = 500 \times 10^{-9} \, \text{m} \)

### (i) Fringe Width (\( \beta \))
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