The angle of minimum deviation for an incident light ray on an equilateral prism is equal to its refracting angle. The refractive index of its material is

$A$ ray of light passes through an equilateral glass prism in such a manner that the angle of incidence is equal to the angle of emergence and each of these angles is equal to $\frac{3}{4}$ of the angle of the prism. The angle of deviation is (in $^{\circ}$)

In the visible region,the dispersive powers and the mean angular deviations for crown and flint glass prisms are $\omega, \omega'$ and $d, d'$ respectively. The condition for getting deviation without dispersion when the two prisms are combined is

$A$ plane polarized blue light ray is incident on a prism such that there is no reflection from the surface of the prism. The angle of deviation of the emergent ray is $\delta=60^{\circ}$ (see Figure-$1$). The angle of minimum deviation for red light from the same prism is $\delta_{\text{min}}=30^{\circ}$ (see Figure-$2$). The refractive index of the prism material for blue light is $\sqrt{3}$. Which of the following statement$(s)$ is(are) correct?
$(A)$ The blue light is polarized in the plane of incidence.
$(B)$ The angle of the prism is $60^{\circ}$.
$(C)$ The refractive index of the material of the prism for red light is $\sqrt{2}$.
$(D)$ The angle of refraction for blue light in air at the exit plane of the prism is $60^{\circ}$.

The angle of minimum deviation measured with a prism is $30^o$ and the angle of the prism is $60^o$. The refractive index of the prism material is:

$A$ deviation of $5^o$ is observed from a prism whose angle is small and whose refractive index is $1.5$. The angle of the prism is.......$^o$