Electrodynamics MOC

Charge Density

Charge density is a measure of how Charge is distributed over space. Like Mass Density and other forms of density, it comes in three forms

TypeSymbol and formula1SI unit
Volume charge density𝜌𝑞 =𝑑𝑄𝑑𝑉C⋅m−3
Surface charge density𝜎𝑞 =𝑑𝑄𝑑𝐴C⋅m−2
Linear charge density𝜆𝑞 =𝑑𝑄𝑑ℓC⋅m−1

These can all be integrated to ascertain a quantity of total contained charge within a solid, surface, or line respectively. In the solid case

𝑄Ω=∭Ω𝜌𝑞𝑑𝑉

#state/tidy | #SemBr

Footnotes

  1. In situations where the type of density being referred to is clear, the subscript may be omitted. ↩