If the source of light used in a Young’s double slit experiment is changed from red to violet

The intensity of light remains the same only the wavelength changes. Hence option (A), (C) cannot be true.

The phase difference is also unchanged. Hence, option (D) is also false.


The fringe width is directly proportional to wavelength. Hence, as wavelength decreases, the fringes will come closer. So option(B) is correct.

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