Two narrow parallel slits illuminated by a coherent monochromatic light produces an interference pattern on a screen placed at a distance $$\mathrm{D}$$ from the slits. The separation between the dark lines of the interference pattern can be increased by

A monochromatic light of wavelength $$800 \mathrm{~nm}$$ is incident normally on a single slit of width $$0.020 \mathrm{~mm}$$ to produce a diffraction pattern on a screen placed $$1 \mathrm{~m}$$ away. Estimate the number of fringes obtained in Young's double slit experiment with slit separation $$0.20 \mathrm{~mm}$$, which can be accommodated within the range of total angular spread of the central maximum due to single slit.

Incident light of wavelength $$\lambda=800 \mathrm{~nm}$$ produces a diffraction pattern on a screen $$1.5 \mathrm{~m}$$ away when it passes through a single slit of width $$0.5 \mathrm{~mm}$$. The distance between the first dark fringes on either side of the central bright fringe is

A slit of width $$10 \times 10^{-7} \mathrm{~m}$$ is illuminated by light of wavelength $$500 \mathrm{~nm}$$. Angular position of the first minimum is