CBSE-XI-Physics
17: Light Waves
- #10If the separation between the slits in a Young’s double slit experiment is increased, what happens to the fringe-width? If the separation is increased too much, will the fringe pattern remain detectable?Ans : The fringe width in Young's double slit experiment depends on the separation of the slits.
`` \chi =\frac{\lambda D}{d}``,
where
`` \lambda =\,\mathrm{\,wavelength\,}``
`` \chi =\,\mathrm{\,fringe\,}\,\mathrm{\,width\,}``
`` D=\,\mathrm{\,distance\,}\,\mathrm{\,between\,}\,\mathrm{\,slits\,}\,\mathrm{\,and\,}\,\mathrm{\,screen\,}``
`` d=\,\mathrm{\,separation\,}\,\mathrm{\,between\,}\,\mathrm{\,slits\,}``
On increasing d, fringe width decreases. If the separation is increased too much, the fringes will merge with each other and the fringe pattern won't be detectable.
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