Gaussian Units: Electric Field

[soupdejour]

I am stuck with Gaussian units. If the field in vacuum is

E = \frac{Q}{r^2}

Is the field in a dielectric

E = \frac{Q}{\epsilon_r r^2}

, or is it unchanged?

 

[Born2bwire]

The latter is the correct equation. In gaussian units, free-space epsilon is unity, this is why I prefer MKS units since all the unities in natural units sometimes hide these kind of relationships.