Source: wikibot/relative-permittivity
= Relative permittivity
{wiki=Relative_permittivity}
Relative permittivity, often denoted as \\( \\epsilon_r \\), is a dimensionless quantity that measures how much electric field is reduced in a material compared to the vacuum. It is the ratio of the permittivity of a substance to the permittivity of free space (vacuum), which is represented by \\( \\epsilon_0 \\).