Given, The distance of sources from the screen, D=0.5 m The distance between the slits, d=0.5 mm=0.0005 m The wavelength of the monochromatic light, λ=5890 A˚=5890×10−10 mY=2β As we know, β=dλD​ Substituting the values in the above equation. Y=2(dλD​)=2(0.00055890×10−10×0.5​)=1178×10−6 m