If Fresnel's biprism experiment is performed in water instead of air,what will be the effect on the fringe width?

$A$ parallel beam of light of intensity $I_0$ is incident on a coated glass plate. If $25 \%$ of the incident light is reflected from the upper surface and $50 \%$ of the light that enters the glass is reflected from the lower surface of the glass plate,the ratio of maximum to minimum intensity in the interference region of the reflected light is

If a biprism experiment is immersed in water,and the fringe width in air is $\beta_a$,find the new fringe width if the refractive index of the biprism material is $1.5$ and the refractive index of water is $1.33$.

In a biprism experiment,a steady interference pattern is observed on the screen using light of wavelength $\lambda_1 = 5000 \ Å$. Without disturbing the setup of the experiment,the source of light is replaced by a source of wavelength $\lambda_2 = 6400 \ Å$. The fringe width will:

When petrol leaking from a vehicle falls on a rain-wet road,colours are observed. This is due to the.......... of light.

In a Fresnel's biprism experiment,coherent sources are obtained by which of the following phenomena?