Electrodynamics (Symbols)¶
Symbols related to electrodynamics.
- admittance¶
Admittance is a measure of how easily a circuit or device will allow a current to flow, defined as the reciprocal of impedance.
- Symbol:
Y- Latex:
\(Y\)
- Dimension:
conductance
- electrical_conductance¶
Conductance is the ability of charge to flow in a certain path. It is the reciprocal of electrical resistance.
- Symbol:
G- Latex:
\(G\)
- Dimension:
conductance
- susceptance¶
Susceptance is the imaginary part of the electrical admittance.
- Symbol:
B- Latex:
\(B\)
- Dimension:
conductance
- electrical_impedance¶
Electrical impedance is the opposition to current presented by the combined effect of resistance and reactance in a circuit.
- Symbol:
Z- Latex:
\(Z\)
- Dimension:
impedance
- wave_impedance¶
Wave impedance is a constant related to electromagnetic wave propagation in a medium.
Links:
- Symbol:
eta- Latex:
\(\eta\)
- Dimension:
impedance
- electromotive_force¶
Electromotive force, also electromotance, abbreviated emf, an energy transfer to an electric circuit per unit of electric charge, measured in volts.
- Symbol:
E- Latex:
\(\mathcal{E}\)
- Dimension:
voltage
- magnetic_flux¶
Magnetic flux through a surface is the surface integral of the normal component of the magnetic field \(\mathbf{B}\) over that surface.
- Symbol:
Phi_B- Latex:
\(\Phi_\mathbf{B}\)
- Dimension:
magnetic_flux
- absolute_permittivity¶
Absolute permittivity, or often sometimes permittivity, is a measure of the electric polarizability of a dielectric material.
- Symbol:
epsilon- Latex:
\(\varepsilon\)
- Dimension:
capacitance/length
- relative_permittivity¶
Relative permittivity is the permittivity of a medium relative to that of free space. Also see
vacuum_permittivity.
- Symbol:
epsilon_r- Latex:
\(\varepsilon_\text{r}\)
- Dimension:
dimensionless
- absolute_permeability¶
Absolute permeability, also called permeability, is the measure of magnetization produced in a material in response to an applied magnetic field.
- Symbol:
mu- Latex:
\(\mu\)
- Dimension:
inductance/length
- relative_permeability¶
Relative permeability is the permeability of a medium relative to that of free space. Also see
vacuum_permeability.
- Symbol:
mu_r- Latex:
\(\mu_\text{r}\)
- Dimension:
dimensionless
- capacitance¶
Capacitance is the capacity of a material object or device to store electric charge.
- Symbol:
C- Latex:
\(C\)
- Dimension:
capacitance
- charge¶
Electric charge is the physical property of matter that causes it to experience a force when placed in an electromagnetic field. It can be positive or negative. Like charges repel each other and unlike charges attract each other.
- Symbol:
q- Latex:
\(q\)
- Dimension:
charge
- voltage¶
Voltage is the difference in electric potential between two points.
- Symbol:
V- Latex:
\(V\)
- Dimension:
voltage
- current¶
Current is a flow of charged particles moving through an electrical conductor or space.
- Symbol:
I- Latex:
\(I\)
- Dimension:
current
- electrical_resistance¶
Resistance is the measure of the degree to which a conductor opposes an electric current through that conductor. It is the real part of the complex-valued impedance.
- Symbol:
R- Latex:
\(R\)
- Dimension:
impedance
- electric_dipole_moment¶
Electric dipole moment is a measure of the separation of positive and negative electrical charges within a system: that is, a measure of the system’s overall polarity.
- Symbol:
p- Latex:
\(p\)
- Dimension:
charge*length
- electric_field_strength¶
Electric field strength refers to the magnitude of the electric field.
- Symbol:
E- Latex:
\(E\)
- Dimension:
voltage/length
- volumetric_charge_density¶
Volume charge density is the electric charge per unit volume.
- Symbol:
rho- Latex:
\(\rho\)
- Dimension:
charge/volume
- surface_charge_density¶
Surface charge density is charge per unit surface area.
- Symbol:
sigma- Latex:
\(\sigma\)
- Dimension:
charge/area
- electric_flux¶
Electric flux through a surface is the surface integral of the normal component of the electric field \(\mathbf{E}\) over that surface.
- Symbol:
Phi_E- Latex:
\(\Phi_\mathbf{E}\)
- Dimension:
length*voltage
- magnetic_flux_density¶
Magnetic flux density, also called magnetic induction, is a physical quantity that predicts the force on a charged particle in the Lorentz force law.
- Symbol:
B- Latex:
\(B\)
- Dimension:
magnetic_density
- electric_potential¶
Electric potential is defined as the amount of work or energy needed per unit of electric charge to move the charge from a reference point to a specific point in an electric field.
- Symbol:
U_E- Latex:
\(U_\mathbf{E}\)
- Dimension:
voltage
- power_factor¶
Power factor of an AC power system is defined as the ratio of the real power absorbed by the load to the apparent power flowing in the circuit.
- Symbol:
pf- Latex:
\(\mathrm{pf}\)
- Dimension:
dimensionless
- electrical_resistivity¶
Electrical resistivity is a fundamental specific property of a material that measures its electrical resistance or how strongly it resists electric current.
- Symbol:
rho- Latex:
\(\rho\)
- Dimension:
impedance*length
- inductance¶
Inductance is the tendency of an electrical conductor to oppose a change in the electric current flowing through it.
- Symbol:
L- Latex:
\(L\)
- Dimension:
inductance
- electric_time_constant¶
Time constant is the parameter characterizing the response to a step input of a first-order, linear time-invariant system. It is related to the speed of the response.
- Symbol:
tau- Latex:
\(\tau\)
- Dimension:
time
- electrical_reactance¶
Reactance is the opposition presented to alternating current by inductance and capacitance.
- Symbol:
X- Latex:
\(X\)
- Dimension:
impedance
- current_density¶
Current density is the amount of charge per unit time that flows through a unit area of a chosen cross section.
- Symbol:
j- Latex:
\(j\)
- Dimension:
current/area
- emissivity¶
The emissivity of the surface of a material is its effectiveness in emitting energy as thermal radiation.
- Symbol:
epsilon- Latex:
\(\varepsilon\)
- Dimension:
dimensionless
- magnetic_moment¶
Magnetic (dipole) moment is a vector physical quantity representing the strength and the orientation of a system that exerts a magnetic field. The magnetic dipole moment of an object determines the magnitude of torque the object experiences in a given magnetic field.
Links:
- Symbol:
m- Latex:
\(m\)
- Dimension:
area*current
- electric_displacement¶
Electric displacement field, also called electric flux density or electric induction, is a vector field, which accounts for the electromagnetic effects of polarization and that of an electric field, combining the two in an auxiliary field.
Links:
- Symbol:
D- Latex:
\(D\)
- Dimension:
charge/area
- attenuation_coefficient¶
Attenuation coefficient, also called attenuation constant, characterizes how easily a volume of material can be penetrated by energy or matter.
Links:
- Symbol:
alpha- Latex:
\(\alpha\)
- Dimension:
1/length
- magnetic_field_strength¶
Magnetic field strength refers to magnitude of the magnetic field.
Links:
- Symbol:
H- Latex:
\(H\)
- Dimension:
current/length
- electrical_conductivity¶
Electrical conductivity is the reciprocal of electrical resistivity, representing a material’s ability to conduct electric current.
Links:
- Symbol:
sigma- Latex:
\(\sigma\)
- Dimension:
1/(impedance*length)
- circuit_gain¶
Gain is a measure of the ability of a two-port circuit (often an amplifier) to increase the power or amplitude of a signal from the input to the output port by adding energy converted from some power supply to the signal.
Links:
- Symbol:
gain- Latex:
\(\text{gain}\)
- Dimension:
dimensionless
- diode_constant¶
Diode constant is the constant of proportionality between the anode current or current density and anode voltage. Refer to Current from voltage and diode constant in vacuum diode.
- Symbol:
g- Latex:
\(g\)
- Dimension:
current/voltage**(3/2)
- direct_permeability_coefficient¶
Direct permeability coefficient characterizes the shielding effect of the grid and shows how much weaker the electrostatic field of the anode is than the field of the grid which affects the cathode area.
- Symbol:
D- Latex:
\(D\)
- Dimension:
dimensionless
- attenuation¶
Attenuation is a quantity measuring the relative amount of power the circuit reduces from the input signal. It is measured in decibels or other relative units of measurement.
Links:
- Symbol:
A- Latex:
\(A\)
- Dimension:
dimensionless
- surge_impedance¶
Surge impedance, or characteristic impedance, of a uniform transmission line is the ratio of the amplitudes of voltage and current of a wave travelling in one direction along the line in the absence of reflections in the other direction.
Links:
- Symbol:
Z_S- Latex:
\(Z_\text{S}\)
- Dimension:
impedance
- reflection_coefficient¶
The reflection coefficient is a parameter that describes how much of a wave is reflected by an impedance discontinuity in the transmission medium.
Links:
- Symbol:
Gamma- Latex:
\(\Gamma\)
- Dimension:
dimensionless
- standing_wave_ratio¶
Standing wave ratio is a measure of impedance matching of loads to the characteristic impedance of a transmission line or waveguide. It is defined as the ratio of the highest to the lowest voltage in the transmission line.
Links:
- Symbol:
SWR- Latex:
\(\text{SWR}\)
- Dimension:
dimensionless
- phase_constant¶
The phase constant, also called phase change constant, is the imaginary component of the propagation constant for a plane wave.
Links:
- Symbol:
beta- Latex:
\(\beta\)
- Dimension:
1/length
- propagation_constant¶
The propagation constant is complex-valued quantity measuring the change undergone by the amplitude and phase of the wave as it propagates in a given direction.
Links:
- Symbol:
gamma- Latex:
\(\gamma\)
- Dimension:
1/length
- dielectric_loss_tangent¶
Dielectric loss tangent (which is the tangent of the dielectric loss angle) quantifies a dielectric material’s inherent dissipation of electromagnetic energy.
Links:
- Symbol:
tan(delta)- Latex:
\(\tan \delta\)
- Dimension:
dimensionless