Question

Question #f17c9

Answer 1

We know the expression for dispersive power `omega` as follows

`omega=(mu_b-mu_r)/(mu_y-1`

where

`mu_b->"refractive index in respect of blue light"`

`mu_r->"refractive index in respect of red light"`

`mu_y->"refractive index in respect of yellow light"`

Given

`omega=0.031" "mu_b=1.665" "mu_r=1.645`

So inserting the values we have

`omega=(mu_b-mu_r)/(mu_y-1`

`=>0.031=(1.665-1.645)/(mu_y-1`

`=>mu_y-1=0.020/0.031`

`=>mu_y=20/31+1=51/31~~1.64516`