Write the Important Characteristic Features by Which the Interference Can Be Distinguished from the Observed Diffraction Pattern. - Physics

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Write the important characteristic features by which the interference can be distinguished from the observed diffraction pattern.

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Solution

Important characteristic features:

1. Interference is the result of the interaction of light coming from two different waves originating from two coherent sources, whereas the diffraction pattern is the result of the interaction of light coming from different parts of the same wavefront.

2. The fringes may or may not be of the same width in case of interference, while the fringes are always of varying width in diffraction.

3. In interference, the fringes of minimum intensity are perfectly dark and all bright fringes are of the same intensity. In diffraction, the fringes of minimum intensity are not perfectly dark and the bright fringes are of varying intensity.

4. There is a good contrast between the bright and dark fringes in the interference pattern. The contrast between the bright and dark fringes in the diffraction pattern is comparatively poor.

Concept: Interference
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2014-2015 (March) Panchkula Set 3

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