Physics - Wave Optics Question with Solution | TestHub

In a biprism experiment, monochromatic light of wavelength ' $\lambda$ ' is used. The distance between two coherent sources ' $\mathrm{d}$ ' is kept constant. If the distance between slit and eyepiece ' $D$ ' is varied as $D_1,D_2,D_3\&D_4$ and corresponding measured fringe widths are $Z_1,Z_2,Z_3$ and $Z_4$ then