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प्रश्न
State Huygen’s principle. Using this principle explain how a diffraction pattern is obtained on a screen due to a narrow slit on which a narrow beam coming from a `=> n = (vlamda)/(vlamda_omega)`monochromatic source of light is incident normally.
उत्तर
Huygen’s Principle
It states that
(i) Rays (light rays) are perpendicular to wave fronts.
Where wave fronts are defined as a surface of constant phase.
(ii) The time taken for light to travel from one wave front to another is same along any ray.
Diffraction Pattern:
Explanation of diffraction phenomena along with the following diagrams.
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