Find the angle of the flint glass prism, which should be combined with a crown glass prism of $5^{\circ }$ to give dispersion but no deviation.
For crown glass: ${\mu }_v=1.523;{\mu }_R=1.515$
For flint glass : ${\mu }^{\prime }{}_v=1.688;{\mu }^{\prime }{}_R=1.650$

Q. A crown glass prism of refracting angle $6^{\circ }$ is to be used for deviation without dispersion with a flint glass of angle of prism a.Given: for crown glass ${\mu }_r=1.513$ and ${\mu }_v=1.523$, for flint glass ${\mu }_r=1.645$ and ${\mu }_v=1.665$. Find a.

Q. A crown glass prism and a flint glass prism are combined to produce dispersion without deviation. Mean refractive indices of crown and flint glass are respectively 1.5 and 1.6. Ratio of angle of crown glass prism to that of flint prism is

Q. Three thin prisms are combined as shown in figure. The refractive indices of the crown glass for red, yellow and violet rays are ${\mu }_r,$ ${\mu }_y$ and ${\mu }_v$ respectively and those for the flint glass are ${\mu }_r^{{}^{\prime }}$, ${\mu }_y^{{}^{\prime }}$ and ${\mu }_v^{{}^{\prime }}$ respectively. Find the $\frac{A^{\prime }}{A}$ for which, there is no net angular dispersion.

Q. Three thin prisms are combined as shown in figure. The refractive indices of the crown glass for red, yellow and violet lights are ${\mu }_r,{\mu }_y$ and ${\mu }_v$ respectively and those for the flint glass are ${\mu }_r^{{}^{\prime }},{\mu }_y^{{}^{\prime }}$ and ${\mu }_v^{{}^{\prime }}$ respectively. Find the $\frac{A^{{}^{\prime }}}{A}$ for which, there is no net angular dispersion.

Q. A thin prism of crown glass (μ_r = 1.515, μ_v = 1.525) and a thin prism of flint glass (μ_r = 1.612, μ_v = 1.632) are placed in contact with each other. Their refracting angles are 5.0° each and are similarly directed. Calculate the angular dispersion produced by the combination.