coulomb per cubic metre

SI coherent derived unit whose name and symbol includes an SI coherent derived unit with a special name and symbol

Name	Symbol	Quantity	Base units
coulomb per cubic metre	C/m³	electric charge density	m⁻³ s A
The coulomb per cubic metre, symbol C/m³, is the SI coherent derived unit of electric charge density.
Definition			c^-3 Δν_Cs³ e
$1 \mspace{4mu} \text{C} / \text{m}^3 \mspace{6mu} = \dfrac{(299 \mspace{4mu} 792 \mspace{4mu} 458)^3}{(9 \mspace{4mu} 192 \mspace{4mu} 631 \mspace{4mu} 770)^3(1.602 \mspace{4mu} 176 \mspace{4mu} 634 \times 10^{-19})} \mspace{6mu} \dfrac{{\Delta \nu _{Cs}}^3 \mspace{4mu} e}{c^3}\\ \\ \\ 1 \mspace{4mu} \text{C} / \text{m}^3 \mspace{6mu} \approx 2.164 \mspace{4mu} 871 \mspace{4mu} 501 \mspace{4mu} 342 \mspace{4mu} 103 \mspace{4mu} 134 \times10^{14} \mspace{6mu} c^{-3} \mspace{4mu} {\Delta \nu _{Cs}}^3 \mspace{4mu} e$

Charge density

In electromagnetism, charge density, or more specifically volume charge density, ρ, is the amount of electric charge per unit volume.

Using SI coherent units,

$\rho \ = \ \dfrac{Q}{V}$

where:

ρ is the charge density in coulombs per cubic metre, symbol C m^-3,
Q is the electric charge in coulombs, symbol C,
V is the volume in cubic metres, symbol m³.

$1 \ \text{C} \ \text{m}^{-3} \ = \ \dfrac{1 \ \text{C}}{1 \ \text{m}^3}$

The term “charge density” can also refer to surface charge density, σ, which is the amount of charge per unit area, or linear charge density, λ, which is the amount of charge per unit length.

Charge density can be either positive or negative, since electric charge can be either positive or negative.