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Question
Write three characteristic features to distinguish between the interference fringes in Young's double slit experiment and the diffraction pattern obtained due to a narrow single slit.
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Solution
1. Interference is the result of interaction of light coming from two different wavefronts originating from two coherent sources,whereas diffraction pattern is the result of interaction of light coming from different parts of the same wavefront.
2. In Interference, the fringes may or may not be of the same width; while in diffraction, the fringes are always of varying widths.
3. In Interference, the bright fringes are of the same intensity; while in diffraction, the bright fringes are of varying intensities.
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