Question

The refractive indices of flints glass prism
for C,D and F lines are
1.790,1.795 and 1.805
respectively. Find the dispersive power of
the flint glass prism.​

Answer 1

Answer:

sorry I didn't understand what you have asked

Answer 2

- 10 degrees

Explanation:

Given: Refractive indices of flint's glass prism for C, D and F lines are 1.790,1.795 and 1.805.

Find: Dispersive power.

Solution: The dispersive power of the material of a prism is defined as the ratio of angular dispersion between two extreme colours, to the deviation produced by the mean colour.

So the extreme colours are C and F lines with refractice indices 1.790 and 1.805 respectively. Mean colour is the D line with refractive index 1.795.

Dispersive power = (1.790 - 1.805) / (1.795 - 1)

 = - 0.015 / 0.795

= - 0.018

Converting to degrees = - 0.18 * 180/π = - 10 degrees approximately.