For an equilateral prism,it is observed that when a ray strikes grazingly at one face,it emerges grazingly at the other. Its refractive index will be

$A$ ray of light suffers minimum deviation when incident on a prism having an angle of the prism equal to $60^{\circ}$. The refractive index of the prism material is $\sqrt{2}$. The angle of incidence (in degrees) is . . . . . . .

$A$ certain prism is found to produce a minimum deviation of $38^\circ$. It produces a deviation of $44^\circ$ when the angle of incidence is either $42^\circ$ or $62^\circ$. What is the angle of incidence when it is undergoing minimum deviation (in $^\circ$)?

$A$ 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 $60^{\circ}$.

If a thin prism of glass is dipped into water,then the minimum deviation (with respect to air) of light produced by the prism will be: $\left( {_a{\mu _g} = \frac{3}{2} \text{ and } _a{\mu _w} = \frac{4}{3}} \right)$

$A$ ray of light is incident at an angle of $60^o$ on one face of a prism of angle $30^o$. The emergent ray of light makes an angle of $30^o$ with the incident ray. The angle made by the emergent ray with the second face of the prism will be....$^o$