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Question
The slits in a Young's double slit experiment have equal width and the source is placed symmetrically with respect to the slits. The intensity at the central fringe is I0. If one of the slits is closed, the intensity at this point will be ____________ .
Options
`I_0`
`I_0/4`
`I_0/2`
`4I_0`
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Solution
`I_0/4`
Total intensity coming from the source is I0 which is present at the central maxima. In case of two slits, the intensity is getting distributed between the two slits and for a single slit, the amplitude of light coming from the slit is reduced to half which leads to 1/4th of intensity.
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