Question

X-ray and visible light travel at the same speed in vacuum. Do they travel at the same speed in glass?

Answer 1

x-ray light can travelin any medium faster

Answer 2

No,the travelling of x-ray is at a faster speed more than the glass’ in visible light.

Explanation:

In any material medium, the speed of the light is inversely proportional to the medium’s refractive index.  

Since, the glass’ index for x-ray is less than the visible light, there will be the travelling of x-ray at a faster speed more than the glass’ visible light.

The refractive index’s formula is below:

$n=c / v$

where, c is the light’s speed in vacuum, n is the refraction index and v is the light’s speed in the medium.