The expected graphical representation of the variation of angle of deviation $\delta$ with angle of incidence $i$ in a prism is:

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

The respective angles of the flint and crown glass prisms are $A'$ and $A$. They are to be used for dispersion without deviation. The ratio of their angles $A'/A$ will be:

$A$ light ray is incident on a prism of angle $A = 30^{\circ}$ at an angle of incidence of $60^{\circ}$. If the emergent ray makes an angle of $30^{\circ}$ with the incident ray,then find the refractive index of the prism $:-$

$A$ 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 $^{\circ}$)?

$A$ prism of refractive index $1.53$ is placed in water of refractive index $1.33$. If the angle of prism is $60^{\circ}$,the angle of minimum deviation in water will be ........$^{\circ}$ $(\sin 35.1^{\circ} = 0.575)$