In Young’s double-slit experiment with monochromatic light, how is the fringe-width affected, if the monochromatic red-light source is replaced by monochromatic violet-light source (of shorter wavelength)?

In Young’s double-slit experiment with monochromatic light, how is the fringe-width affected, if the Young’s apparatus be immersed in water?

What is the effect of the following operations on the interference fringes in Young’s double-slit experiment?

The width of the source slit is increased.

What is the effect of the following operations on the interference fringes in Young’s double-slit experiment?

The source slit is moved closer to the double-slit.

If in Young’s experiment, the distance $d$ between the slits is kept smaller than the wavelength $\lambda$ of light, the interference pattern will not be seen. Why?

When a thin transparent film is placed just in front one of the slits in Young’s double-slit experiment using white light, what change results in fringe-system?

The phase difference between the light-waves emerging from the slits of Young’s experiment is $\mathrm{\pi }$ radian. Will the central fringe be bright or dark? Explain with reason.

State with reason whether diffraction of light takes place at the two slits in Young’s interference experiment.