Why is it that some materials fight the flow of electricity while others embrace it?
Electrical conductivity is defined as a measure of how readily a material allows an electric current to pass through it. This is in contrast to electrical resistivity, which is a measure of how strongly a material opposes the flow of an electric current.
The precise conductivity level of a material is found by determining its magnitude of current density by the magnitude of its electric field. Simply put, this means that a material that can pull a large amount of current through it – even with an intrinsically small electric field – is a good conductor due to its low resistivity to electron flow.
Electron flow is characterised in a meta 1 by the dissociation of its atoms’ outer electrons from its structural lattice. These free electrons, when an electrical potential difference (ie voltage) is applied, proceed to travel from one end of a material to the other under the influence of its internal electric field.
Examples of good electrical conductors include copper, gold and silver – the latter being the most electrically conductive of all metals. However, don’t be fooled into thinking that non-metallic materials are not capable of conducting electricity, as plasma, salt solutions and even the carbon-based graphite all can boast high conductivity levels.