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MHT CET 2023 (13 May, Shift 1) · Biprism, Thin Films & Other Devices

Biprism, Thin Films & Other Devices question from MHT CET 2023 (13 May, Shift 1)

Q17MHT CET 2023 · 13 MAY · SHIFT 1Easy

Biprism, Thin Films & Other Devices

In a biprism experiment, monochromatic light of wavelength 'λ\lambda' is used. The distance between two coherent sources 'dd' is kept constant. If the distance between slit and eyepiece 'DD' is varied as D1,D2,D3&D4D_1, D_2, D_3 \& D_4 and corresponding measured fringe widths are Z1,Z2,Z3Z_1, Z_2, Z_3 and Z4Z_4 then

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Answer: (b)

  1. Z=λDdZ = \frac{\lambda D}{d} with λ\lambda, dd fixed, so Z∝DZ \propto D.
  2. Hence ZD=λd\frac{Z}{D} = \frac{\lambda}{d} is constant.
  3. So the answer is (b) Z1D1=Z2D2=Z3D3=Z4D4\frac{Z_1}{D_1} = \frac{Z_2}{D_2} = \frac{Z_3}{D_3} = \frac{Z_4}{D_4}.
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