Electrical conductivity is a measure of how easily electric current can flow through a material. It is typically represented by the symbol σ and is measured in units of siemens per meter (S/m).
Conductivity and resistivity are inversely related. While conductivity measures how easily current can flow through a material, resistivity measures how much the material resists the flow of current. Resistivity is typically represented by the symbol ρ and is measured in units of ohm-meters (Ω·m).
The conductivity of a material is affected by its composition, temperature, and the presence of impurities or defects. Generally, materials with higher concentrations of free electrons or ions have higher conductivity.
Permittivity is a measure of a material's ability to store an electric charge. In other words, it is a measure of how much a material can be polarized by an applied electric field. It is typically represented by the symbol ε and is measured in units of farads per meter (F/m). Permittivity and conductivity are related through the equation ε = ε0 + σ/ω, where ε0 is the permittivity of free space, σ is the conductivity, and ω is the angular frequency of the applied electric field.
Permeability is a measure of a material's ability to support the formation of a magnetic field. It is typically represented by the symbol μ and is measured in units of henrys per meter (H/m). Permeability is related to conductivity and permittivity through the equation μ = μ0(1 + χm), where μ0 is the permeability of free space and χm is the magnetic susceptibility of the material.