When a mica sheet of thickness $7 \ \mu m$ and refractive index $\mu = 1.6$ is placed in the path of one of the interfering beams in a biprism experiment, the central fringe shifts to the position of the seventh bright fringe. The wavelength of the light used is $............ \ \mathring{A}$.

In a Fresnel biprism experiment,which of the following light sources is used to identify the central fringe?

In a biprism experiment, the distance of the source from the biprism is $1 \, m$ and the distance of the screen from the biprism is $4 \, m$. The refracting angle of the biprism is $\alpha = 2 \times 10^{-3} \, \text{radians}$. The refractive index $\mu$ of the biprism is $1.5$ and the wavelength of light used is $\lambda = 6000 \, \mathring{A}$. How many fringes will be seen on the screen?

Light is incident on a glass plate $(\mu = 1.5)$ at an angle of $60^o$. A dark fringe is observed corresponding to a wavelength of $6000 \, \mathring{A}$. If the thickness of the glass plate is $1.2 \times 10^{-3} \, mm$, find the order of the interference fringe.

Choose the correct statement.

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