In Young's double slit experiment the two slits 0.12 mm apart are illuminated by monochromatic light of wavelength 420 nm. The screen is 1.0 m away from the slits .
(a) Find the distance of the second (i) bright fringe , (ii) dark fringe from the central maximum .
(b) How will the fringe pattern change if the screen is moved away from the slits ?

Explanation

To solve the problem step by step, we will first gather the given data and then apply the relevant formulas for Young's double slit experiment.

### Given Data:
- Distance between the slits, \( d = 0.12 \, \text{mm} = 0.12 \times 10^{-3} \, \text{m} = 1.2 \times 10^{-4} \, \text{m} \)
- Wavelength of light, \( \lambda = 420 \, \text{nm} = 420 \times 10^{-9} \, \text{m} \)
- Distance from the slits to the screen, \( D = 1.0 \, \text{m} \)

### Part (a): Find the distance of the second bright fringe and the second dark fringe from the central maximum.
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