(i) Write two points to distinguish between interference and diffraction fringes.
(ii) In a Young 's double slit experiment , fringes are obtained on a screen placed at certain distance away from the slits . If the screen is moved by 5 cm towards the slits , the fringe width changes by 30 `mu m` . Given that the slits are 1 mm apart , calculate the wavelength of the light used.

Explanation

### Step-by-Step Solution

#### Part (i): Distinguishing Between Interference and Diffraction Fringes

1. **Definition of Interference Fringes**:
- Interference fringes are the result of the superposition of two or more coherent light waves. They are characterized by alternating bright and dark bands on a screen due to constructive and destructive interference.

2. **Definition of Diffraction Fringes**:
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