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प्रश्न
In Young's double slit experiment, plot a graph showing the variation of fringe width versus the distance of the screen from the plane of the slits keeping other parameters same. What information can one obtain from the slope of the curve?
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उत्तर
The fringe width in Young's double slit experiment is given by
β=λD/d/
whereλ=Wavelength of source
D=Distance between the slits and screen
d=Distance between the slits
⇒β∝D
The variation of fringe width with distance of screen from the slits is given by the graph shown below:
It is a linear graph with slope equal to λ/d. So, for the fringe width to vary linearly with distance of screen from the slits, the ratio of wavelength to distance between the slits should remain constant. Therefore, it is advised to take wavelengths of incident light nearly equal to the width of the slit.
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संबंधित प्रश्न
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If one of two identical slits producing interference in Young’s experiment is covered with glass, so that the light intensity passing through it is reduced to 50%, find the ratio of the maximum and minimum intensity of the fringe in the interference pattern.
What is the effect on the interference fringes to a Young’s double slit experiment when
(i) the separation between the two slits is decreased?
(ii) the width of a source slit is increased?
(iii) the monochromatic source is replaced by a source of white light?
Justify your answer in each case.
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- the least distance from the central maximum where the bright fringes due to both wavelengths coincide.
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