Question

If the refractive index of second medium with respect to first medium is ¹n₂ and that of third medium with respect to second medium is ²n₃, what and how much is ¹n₃?

Answer 1

The refractive index of the third medium with respect to the first medium is the product of the two given relative refractive indices.

The Formula:

¹n₃ = ¹n₂ × ²n₃

How It Works

¹n₂ = `(n_2)/(n_1)`

²n₃ = `(n_3)/(n_2)`

Multiplying them cancels out the second medium (n₂):

`(n_2)/(n_1) xx (n_3)/(n_2)`

= `(n_3)/(n_1)`

= ¹n₃