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Electromagnetic Quantities
The table below shows the symbol and SI unit for most of the physical quantities that are included with the AC/DC Module.
Table 2-1: Electromagnetic Quantities
Quantity
Symbol
SI Unit
Abbreviation
Angular frequency
 ω
radian/second
rad/s
Attenuation constant
 α
meter-1
m-1
Capacitance
 C
farad
F
Charge
 q
coulomb
C
Charge density (surface)
 ρs
coulomb/meter2
C/m2
Charge density (volume)
 ρ
coulomb/meter3
C/m3
Current
 I
ampere
A
Current density (surface)
 Js
ampere/meter
A/m
Current density (volume)
 J
ampere/meter2
A/m2
Electric displacement
 D
coulomb/meter2
C/m2
Electric field
 E
volt/meter
V/m
Electric potential
 V
volt
V
Electric susceptibility
 χe
(dimensionless)
-
Electrical conductivity
 σ
siemens/meter
S/m
Energy density
 W
joule/meter3
J/m3
Force
 F
newton
N
Frequency
 ν
hertz
Hz
Imaginary unit
j, i
(dimensionless)
-
Impedance
 Z, η
ohm
 Ω
Inductance
 L
henry
H
Magnetic current density (surface)
Jms
volt/meter
-
Magnetic field
 H
ampere/meter
A/m
Magnetic flux
 Φ
weber
Wb
Magnetic flux density
 B
tesla
T
Magnetic potential (scalar)
 Vm
ampere
A
Magnetic potential (vector)
 A
weber/meter
Wb/m
Magnetic susceptibility
 χm
(dimensionless)
-
Magnetization
 M
ampere/meter
A/m
Permeability
 μ
henry/meter
H/m
Permittivity
 ε
farad/meter
F/m
Polarization
 P
coulomb/meter2
C/m2
Poynting vector
 S
watt/meter2
W/m2
Propagation constant
 β
radian/meter
rad/m
Reactance
 X
ohm
 Ω
Relative permeability
 μr
(dimensionless)
-
Relative permittivity
 εr
(dimensionless)
-
Resistance
R 
ohm
 W
Resistive loss
 Q
watt/meter3
W/m3
Torque
 T
newton-meter
N·m
Velocity
 v
meter/second
m/s
Wavelength
 λ
meter
m
Wave number
 k
radian/meter
rad/m