ΔW=d⋅μλD=1.5×10−3×1.44690×10−9×0.72⇒ΔW=2.3×10−4 m=0.23 mm
Young's double slit inteference apparatus is immersed in a liquid of refractive index 1.44. It has slit separation of 1.5 mm . The slits are illuminated by a parallel beam of light whose wavelength in air is 690 nm . The fringe-width on a screen placed behind the plane of slits at a distance of 0.72 m , will be :
Held on 24 Jan 2025 · Verified 6 Jul 2026.
0.23 mm
0.33 mm
0.63 mm
0.46 mm
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