For a thin prism,if the angle of prism is $4^{\circ}$ and the refractive index is $1.6$,then the angle of minimum deviation will be . . . . . . . (in $^{\circ}$)

$A$ ray of light passes through an equilateral prism $(\mu = 1.5)$ such that the angle of incidence is equal to the angle of emergence,and the latter is equal to $3/4$ of the prism angle. The angle of deviation is.......$^o$

Derive ${D_m} = A({n_{21}} - 1)$ for a thin prism.

When white light passes through a glass prism,one gets a spectrum on the other side of the prism. In the emergent beam,the ray which deviates the least is:

In the given figure,what is the angle of the prism?

$A$ light ray is incident on a prism at an angle of $45^o$ and produces minimum deviation. If the refractive index of the prism is $\sqrt{2}$,then the prism angle is .......... $^o$.