# What is speed of o-ray and e-ray and how to obtained?

what is speed of o-ray and e-ray and how to obtained??

## Homework Statement

that's all for the questions. How do i calculate speed of o-ray and e-ray (for example, e-ray and o-ray of calcite)
thank you

none

## The Attempt at a Solution

What do you mean by "calculate"? Starting with what? These are experimental quantities.
What is given?

i mean the formula to calculate it, any formula with any values (such as wavelength, h, c, m, T, f.....).

As I said, these values are experimentally determined. They depend on the specific material so there is no way to express them just in terms of fundamental constants.
It's very difficult (if not impossible) to predict the values just from first principles. You need some sort of model for the crystal (calcite in your case) that will include some specific parameters (like interaction forces, atom spacing; also atomic properties like pollarizability and I don't know what else.)

Maybe you mean some empirical formula, that represent the experimental data over some wavelength range?