If $r$ and $r^1$ denote the angles of refraction at the two faces of a prism with a prism angle of $50^{\circ}$,and $r$ varies with time $t$ as $r = 10^{\circ} + t^2$,how will $r^1$ vary with time?

$A$ light ray is incident at an angle of $60^o$ on a prism of angle $45^o$. When the light ray emerges from the other surface at $90^o$ to the surface,the refractive index of the material of the prism $\mu$ and the angle of deviation $\delta$ are given by:

The refractive index of the material of a small-angled prism is $1.6$. If the angle of minimum deviation is $4.2^{\circ}$,the angle of the prism is: (in $^{\circ}$)

Three prisms of crown glass,each having a prism angle of $9^o$,and two prisms of flint glass are used to make a direct vision spectroscope. What will be the angle of the flint glass prisms in degrees if the refractive index $\mu$ for flint glass is $1.60$ and $\mu$ for crown glass is $1.53$ (in $^o$)?

For a small angled prism with prism angle $A$,the angle of minimum deviation $(\delta_m)$ varies with the refractive index $(\mu)$ of the prism as shown in the graph.

$A$ ray of light is incident at $60^{\circ}$ on one face of a prism of angle $30^{\circ}$. The emergent ray makes an angle of $30^{\circ}$ with the incident ray. The refractive index of the prism is