Question

Prism angle of prism is 10°. Their refractive index for red and voilet colour is 1.51 and 1.52 respectively.Then despersive power will be?

Answer 1

Refractive index of red colour,u2=1.51
Refractive index of Violet colour,u1 =1.52

Average refractive index,u=(u1+u2)/2
=(1.51+1.52)/2=1.515

Dispersive power =(u1-u2)/(u-1)
=(1.52-1.51)/0.515
=0.01/0.515
=0.019