The refracting angle of a prism is $A,$ and the refractive index of the material of the prism is $\cot(A/2).$ The angle of minimum deviation is:

$A$ thin prism $P_{1}$ with angle $4^{\circ}$ and made from glass of refractive index $1.54$ is combined with another thin prism $P_{2}$ made from glass of refractive index $1.72$ to produce dispersion without deviation. The angle of prism for $P_{2}$ is (in $^{\circ}$)

The angle of minimum deviation is equal to the angle of the equilateral prism. At what angle of incidence $i$ will this minimum deviation occur?

$A$ combination of two prisms,one of flint glass and another of crown glass,produces dispersion without deviation. The angle of the flint glass prism is $15^o$. The angle of the crown glass prism and the net angular dispersion will be respectively: (Given: for crown glass $\mu = 1.52, \omega = 0.02$; for flint glass $\mu = 1.65, \omega = 0.03$). (in $^o$)

$A$ ray of light is incident on a $60^{\circ}$ prism at the minimum deviation position. The angle of refraction at the first face (i.e.,incident face) of the prism is.......$^{\circ}$

If the angle of minimum deviation is equal to the angle of an equilateral prism,then the speed of light inside the prism is .....