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The angular width of the central maximum in a single slit diffraction pattern is 60º. The width of the slit is 1 μm. The slit is illuminated by monochromatic plane waves. If another slit of same width is made near it, Young's fringes can be observed on a screen placed at a distance 50 cm from the slits. If the observed fringe width is 1 cm, what is slit separation distance ? (i.e. distance between the centres of each slit.)

1. 25 μm
2. 50 μm
3. 75 μm
4. 100 μm Students may find similar question in CP exercise sheet : [ JEE Main, Chapter : Wave Optics (Diffraction), Formula based in Class Notes ]

Correct answer: 25 μm

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