MCQ
In Young's double slit experiment, the interference pattern obtained with white light will be:
  • A
    The central fringe bright and alternate bright and dark fringes.
  • The central fringe achromatic and coloured fringes for small path difference.
  • C
    The central fringe dark
  • D
    The central fringe coloured

Answer

Correct option: B.
The central fringe achromatic and coloured fringes for small path difference.

If white light is used a white centre fringe is observed, but all the other fringes have coloured edges, the blue edge being nearer the centre. Eventually the fringes overlap and a uniform white light is produced.

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