$A$ prism of angle $A=1^{\circ}$ has a refractive index $\mu=1.5$. $A$ good estimate for the minimum angle of deviation (in degrees) is close to $N/10$. The value of $N$ is......

$A$ thin prism of angle $6^{\circ}$ made of glass of refractive index $1.5$ is combined with another prism made of glass of refractive index $1.75$ to produce dispersion without deviation. Then the angle of the second prism is ...... (in $^{\circ}$)

In the visible region, the dispersive powers and the mean angular deviations for crown and flint glass prisms are $\omega, \omega^{\prime}$ and $d, d^{\prime}$ respectively. The condition for obtaining dispersion without deviation, when the two prisms are combined, is:

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

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:

$A$ prism of refractive index $\mu$ and angle $A$ is placed in the minimum deviation position. If the angle of minimum deviation is $A,$ then the value of $A$ in terms of $\mu$ is