$A$ yellow light undergoes minimum deviation through a prism. If $i_1$ and $i_2$ are the angle of incidence and the angle of emergence respectively,then:

$A$ thin prism $P_1$ with angle $6^{\circ}$ and made from glass of refractive index $1.54$ is combined with another thin prism $P_2$ of refractive index $1.72$ to produce dispersion without deviation. The angle of prism $P_2$ will be

$A$ flint glass prism is joined with a crown glass prism to produce dispersion without deviation. The refractive indices of these for mean rays are $1.602$ and $1.500$ respectively. If the angle of the flint glass prism is $10^{\circ}$,then the angle of the crown glass prism will be:

As shown in the diagram, when the incident ray is parallel to the base of the prism, the emergent ray grazes along the second surface. If the refractive index of the material of the prism is $\sqrt{2}$, the angle $\theta$ of the prism is: (in $^{\circ}$)

$A$ thin prism $P_1$ with angle $4^o$ made of glass of refractive index $1.54$ is combined with another thin prism $P_2$ made of glass of refractive index $1.72$ to produce no deviation. The angle of prism $P_2$ is.....$^o$

The path of a refracted ray of light in a prism is parallel to the base of the prism only when the