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Question
If the source of light used in a Young's double slit experiment is changed from red to violet, ___________ .
Options
the fringes will become brighter
consecutive fringes will come closer
the intensity of minima will increase
the central bright fringe will become a dark fringe
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Solution
consecutive fringes will come closer
Fringe width,
\[\beta = \lambda D/d\]
Wavelength of red light is greater than wavelength of violet light; so, the fringe width will reduce.
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