Consider two coherent sources of light and are placed at a distance apart and a screen is placed at a distance from the two sources. Let be a point on the screen at a distance from the centre of the screen. If is the path difference between the light waves then,
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In right-angled , we have
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Also in right-angled , we have
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Thus, or
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Since, (the path difference)
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Thus, or
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In practice,
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Hence, or
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. This is the expression for path difference.
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The point will be a centre of bright fringe, if
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or
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, where,
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Similarly, the point will be a centre of dark fringe, if
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or
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, where,
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The spacing between any two consecutive bright fringes or dark fringes is called fringe width. It is represented by .
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Thus, (for bright fringe) and
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(for dark fringe)
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Thus, it is clear that,
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\n"},"comment":{"@type":"Comment","text":"Determine the expression of path difference in terms of distance between slits, distance between sources and screen."},"encodingFormat":"text/markdown","learningResourceType":"Practice problem","suggestedAnswer":[],"text":"Derive the expression for the fringe width in Young's double slit experiment."},"name":"Quiz on Wave Optics","typicalAgeRange":"10-17","url":"https://www.embibe.com/questions/Derive-the-expression-for-the-fringe-width-in-Young%27s-double-slit-experiment./EM6462839"}
Embibe Experts Physics Solutions for Exercise - Embibe Experts Solutions for Chapter: Wave Optics, Exercise 1: chhattisgarh board-2019
Attempt the free practice questions on Chapter 10: Wave Optics, Exercise 1: chhattisgarh board-2019 with hints and solutions to strengthen your understanding. EMBIBE CHAPTER WISE PREVIOUS YEAR PAPERS FOR PHYSICS solutions are prepared by Experienced Embibe Experts.
Questions from Embibe Experts Solutions for Chapter: Wave Optics, Exercise 1: chhattisgarh board-2019 with Hints & Solutions