The angle of deviation produced by a thin prism when placed in air is $\delta_1$ and that when immersed in water is $\delta_2$. The refractive indices of glass and water are $\frac{3}{2}$ and $\frac{4}{3}$ respectively. The ratio $\delta_1 : \delta_2$ is

If a prism having refractive index $\sqrt{3}$ has an angle of minimum deviation equal to the refracting angle of the prism,then the refracting angle of the prism is......$^o$

$A$ light ray is incident at an angle $\theta$ on the refracting surface of a prism and emerges normally from the other surface. If the prism angle is $5^{\circ}$ and the refractive index of the material of the prism is $1.5$,then the angle of incidence is ...$^{\circ}$.

$A$ light ray incident normally on one face of an equilateral prism and emerges out grazingly at the other face. The refractive index of the prism is

An isosceles glass prism with base angles $40^{\circ}$ is clamped over a tray of water in a position such that the base is just dipped in water. $A$ ray of light incident normally on the inclined face suffers total internal reflection at the base. If the refractive index of water is $1.33$,then the condition imposed on the refractive index $\mu$ of the glass is

$A$ flint glass prism and a crown glass prism are to be combined in such a way that the deviation of the mean ray is zero. The refractive indices of flint and crown glasses for the mean ray are $1.620$ and $1.518$ respectively. If the refracting angle of the flint prism is $6.0^{\circ}$,what would be the refracting angle of the crown prism (in $^{\circ}$)?