For a given light wavelength corresponding a medium of refractive index μ
λmed=μλvacumm.
And we know that fringe width β=dλD
Therefore, βmed=μβvacuum=3412=9mm
In young's double slit experiment, the fringe width is 12mm. If the entire arrangement is placed in water of refractive index 34, then the fringe width becomes (in mm)
Held on 26 Jul 2022 · Verified 6 Jul 2026.
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