In a double slit experiment, when one of the slits is covered by a transparent mica sheet of refractive index 1.56, the central fringe shifts to the position of 7 ^(th) bright fringe, obtained with both slits uncovered. If the light source wavelength is 450 nm, the thickness of mica sheet is α×10⁻⁹ m. The value of α is _ _ _.

Optics: JEE Main 2026 Physics question

JEE Main 2026 · 4 Apr, Evening shift · Q50

JEE Main 20264 Apr, Evening shiftPhysicsMediumOptics190× since 2002

In a double slit experiment, when one of the slits is covered by a transparent mica sheet of refractive index 1.56, the central fringe shifts to the position of 7

^{\text{th}}

bright fringe, obtained with both slits uncovered. If the light source wavelength is 450 nm, the thickness of mica sheet is

\alpha\times10^{-9}

m. The value of

\alpha

is ______.

Your answerType your answer. Integers and decimals are accepted.

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