Find the angle of a prism of dispersive power 0.020 and refractive index 1.60 to form an achromatic combination with the prism of angle `4^@` and dispersive power 0.040 having refractive index 1.75. Also calculate the resultant deviation.

Calculate the angle of a prism of dispersive power 0.021 and refractive index 1.53 to form an achromatic combination with prism of angle 4.2^@ , and dispersive power 0.045 , having refractive index 1.65 . Find also the net deviation.

Find the angle fo a prism of dispersive power 0.021 and refractive index 1.53 to form an achromatic combination with prism of angle 4.2^@ and dispersive power 0.045 having refractive index 1.65.Find the resultant deviation.

It is required to form an achromatic combination of two prisms of dispersive powers 0.04 and 0.06 respectively . If the first prism has a refracting angle of 10^(@) and mean refractive index of 1.52 , what must be the refracting angle of the second prism , if its mean refractive index is 1.56 ?

The refracting angle of a prism is 60^@ nd the refractive index of the material of the prism is 1.732.Calculate the angle of minimum deviation.

The refractive index of the prism for violet colour is 1.7 and that for red is 1.65. Then dispersive power of the material of prism is

The refractive index of the prism for violet colour is 1.7 and that for red is 1.65. Then dispersive power of the material of prism is