EEE Course Definitions & Glossary

eee-1109 EEE-1109 Basic Electrical Engineering

1. DC Circuit Fundamentals and Basic Laws

Definition/Statement	Description/Actual Text	Year(s) of Appearance
Charge (Electric Charge)	The most basic quantity in an electric circuit. The concept of electric charge is the underlying principle for explaining all electrical phenomena.	External (Alexander)
Current (i)	The rate of charge flow past a given point in a given direction. It is defined as $i=dq/dt$.	External (Alexander)
Voltage (Potential Difference)	The energy required to move a unit charge from a reference point (–) to another point (+), measured in volts (V). It is the energy required to move 1 C of charge from a reference point (–) to another point (+).	External (Alexander)
Power (p) (Instantaneous)	The energy supplied or absorbed per unit time. It is also the product of voltage and current: $p=vi$.	External (Alexander)
Energy (w)	The capacity to do work, measured in joules (J).	External (Alexander)
electric circuit.	An interconnection of electrical elements.	2022, External (Alexander)
active element. / active components.	An active element is capable of generating energy.	2016, 2017, 2019, 2022, 2023
passive element/network.	A passive element is not capable of generating energy.	2016, 2017, 2019, 2023
unilateral circuit/element.	A unilateral circuit allows current to flow only in one direction, and its characteristics change with direction of current or voltage. Example: Diode.	2016, 2018, 2022
bilateral circuit/element.	A bilateral circuit allows current to flow equally in both directions, with same V–I relationship for each. Examples: Resistor, inductor, capacitor.	2016, 2018, 2019
mesh (with proper example).	A loop is said to be a mesh if it does not contain any other loops within it.	2016, 2019, 2022, External (Alexander)
**loop	Any closed path in a circuit. A closed path formed by starting at a node, passing through a set of nodes, and returning to the starting node without passing through any node more than once.	2017, 2019, 2022
node.	The point of connection between two or more branches. If a short circuit (a connecting wire) connects two nodes, the two nodes constitute a single node.	2017, 2022
Branch	A Branch represents a single element such as a voltage source or a resistor. A branch represents any two-terminal element.	2022, External (Alexander)
linear circuit.	Linearity is the property of an element describing a linear relationship between cause and effect.	2017, 2018, 2019, External (Alexander)
nonlinear circuit.	A nonlinear circuit has elements where the current–voltage relationship is not linear. Examples: Diode, transistor.	2017, 2018, 2019
Resistor.	A passive element in which the voltage $v$ across it is directly proportional to the current $i$ through it. It is a device that obeys Ohm’s law.	External (Alexander)
Conductance (G).	The reciprocal of resistance: $G=1/R$.	External (Alexander)
Ohm’s Law.	States that the voltage $v$ across a resistor is directly proportional to the current $i$ flowing through the resistor: $v=iR$.	External (Alexander)
Kirchhoff’s Current Law (KCL).	States that the algebraic sum of currents entering a node (or a closed boundary) is zero. Alternatively, the sum of the currents entering a node is equal to the sum of the currents leaving the node.	External (Alexander)
Kirchhoff’s Voltage Law (KVL).	States that the voltages around a closed path algebraically sum to zero. In other words, the sum of voltage rises equals the sum of voltage drops.	External (Alexander)
Independent Source.	An active element that provides a specified voltage or current that is completely independent of other circuit elements.	2016, 2019, 2024, External (Alexander)
Dependent (Controlled) Source.	An active element in which the source quantity is controlled by another voltage or current.	2016, 2019, 2024, External (Alexander)
Equivalent (Sources/Circuits).	Two sources (or circuits in general) are said to be equivalent if they have the same $i-v$ relationship at a pair of terminals.	External (Alexander)
Series Elements.	Elements are in series when they are chain-connected or connected sequentially, end to end.	External (Alexander)
Parallel Elements.	Elements in parallel are connected to the same pair of terminals.	External (Alexander)
Passive Sign Convention.	Power assumes a positive sign when the current enters the positive polarity of the voltage across an element.	External (Alexander)
open and short circuits.	A short circuit is a circuit element with resistance approaching zero ($R=0$). An open circuit is a resistor with infinite resistance ($R=\infty$), resulting in zero current flow.	2017, External (Alexander)

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2. DC Circuit Analysis and Network Theorems

Definition/Statement	Description/Actual Text	Year(s) of Appearance
What is supernode?	A supernode is formed by enclosing a (dependent or independent) voltage source connected between two nonreference nodes and any elements connected in parallel with it.	2018, External (Alexander)
Supermesh.	A supermesh results when two meshes have a (dependent or independent) current source in common.	External (Alexander)
Source transformation.	The process of replacing a voltage source $v_s$ in series with a resistor $R$ by a current source $i_s$ in parallel with a resistor $R$, or vice versa. Source transformation requires that $v_s=i_{s}R$ or $i_s=v_s/R$.	External (Alexander)
Thevenin’s theorem.	States that a linear two-terminal circuit can be replaced by an equivalent circuit consisting of a voltage source $V_{Th}$ in series with a resistor $R_{Th}$. $V_{Th}$ is the open-circuit voltage at the terminals, and $R_{Th}$ is the input or equivalent resistance at the terminals when independent sources are turned off.	External (Alexander)
Norton’s theorem.	States that a linear two-terminal circuit can be replaced by an equivalent circuit consisting of a current source $I_N$ in parallel with a resistor $R_N$. $I_N$ is the short-circuit current through the terminals.	External (Alexander)

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3. Magnetic Circuits and Coupling

Definition/Statement	Description/Actual Text	Year(s) of Appearance
reluctance.	Reluctance is the opposition offered by a magnetic circuit to the establishment of magnetic flux. It is the magnetic analogue of electrical resistance.	2016, 2017, 2018, 2019, 2024
permeability.	Permeability is a measure of how easily magnetic flux can be formed in a material.	2017, 2018, 2019
permeance.	Permeance is the ability of a magnetic material or path to allow magnetic flux to pass through it. It is the reciprocal of reluctance.	2016
mmf (Magnetomotive Force).	Magnetomotive force is the driving force that produces magnetic flux in a magnetic circuit. It is analogous to electromotive force (voltage) in an electrical circuit.	2016
Flux density.	Flux density is the amount of magnetic flux passing through a unit area placed perpendicular to the flux.	2024
Magnetizing force.	Magnetizing force is the magnetic field strength produced by a current-carrying coil, responsible for creating magnetic flux in a material.	2024
What is hysteresis loop?	A hysteresis loop is the closed curve obtained when a magnetic material is cycled through magnetization and demagnetization, plotting magnetic flux density B against magnetizing force H.	2023
magnetic coupling.	When two loops affect each other through the magnetic field generated by one of them, they are said to be magnetically coupled. The phenomenon where flux caused by current in one coil links with another coil, inducing voltage, is mutual inductance.	2016, 2019
coupled circuits.	Circuits that affect each other through the magnetic field.	2022, 2023
Mutual Inductance.	The phenomenon where the magnetic flux caused by current in one coil links with the other coil, thereby inducing voltage in the latter.	External (Alexander)
Transformer.	An electrical device designed on the basis of magnetic coupling that uses magnetically coupled coils to transfer energy from one circuit to another.	External (Alexander)
Linear (Loosely Coupled) Transformer.	A transformer where the coils are wound on a magnetically linear material (like air or plastic). May be called an air-core transformer.	External (Alexander)
Ideal (Iron-Core) Transformer.	A unity-coupled, lossless transformer in which the primary and secondary coils have infinite self-inductances. Iron-core transformers are close approximations to ideal transformers.	External (Alexander)
Autotransformer.	A transformer in which both the primary and the secondary are in a single winding.	External (Alexander)

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4. Capacitors and Inductors (Storage Elements)

Definition/Statement	Description/Actual Text	Year(s) of Appearance
Storage Elements.	Elements (inductors or capacitors) that store or release energy (i.e., have a memory).	External (Alexander)
Capacitor.	An element constructed of two conducting plates separated by an insulator (dielectric).	External (Alexander)
Capacitance (C).	The ratio of the charge ($q$) on one plate of a capacitor to the voltage ($v$) across the capacitor.	External (Alexander)
Inductor.	A passive element designed to store energy in its magnetic field.	External (Alexander)
Inductance (L).	The property whereby an inductor exhibits opposition to the change of current flowing through it.	External (Alexander)

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5. AC Fundamentals and Single Phase Circuits

Definition/Statement	Description/Actual Text	Year(s) of Appearance
alternating circuit/current (ac).	A sinusoidal current is usually referred to as alternating current (ac). If the current flows in both directions, then we have ac.	2016, 2017, 2018, 2019, External (Alexander)
What is phase?	Phase refers to the position or stage of an oscillating quantity within its cycle, measured relative to a reference.	2018
Period (T).	The time of one complete cycle or the number of seconds per cycle of the periodic function.	2019, External (Alexander)
Cyclic Frequency (f).	The reciprocal of the period $T$, or the number of cycles per second.	2019, External (Alexander)
RMS value/Effective value.	The effective value of a periodic current is the dc current that delivers the same average power to a resistor as the periodic current. The effective value is often known as the root-mean-square value (rms value).	2016, 2018, 2024, External (Alexander)
Peak factor/Crest Factor.	Peak (or Crest) Factor is the ratio of the maximum (peak) value of a waveform to its RMS value. It indicates how “peaky” or sharp a waveform is.	2017, 2024
form factor.	Form Factor is the ratio of the RMS value of a waveform to its average (mean) value over one cycle.	2017
Phasor (V).	A complex number that represents the amplitude and phase of a sinusoid. A mathematical equivalent of a sinusoid with the time dependence dropped.	External (Alexander)
Impedance (Z).	The opposition that the circuit exhibits to the flow of sinusoidal current. The ratio of the phasor voltage $V$ to the phasor current $I$ ($Z=V/I$).	External (Alexander)
Admittance (Y).	The reciprocal of impedance, measured in siemens (S). It is the ratio of the phasor current through it to the phasor voltage across it ($Y=I/V$).	External (Alexander)
Reactance (X).	The imaginary part of impedance.	External (Alexander)
Susceptance (B).	The imaginary part of admittance.	External (Alexander)
real power (P).	The average power in watts delivered to a load; it is the only useful power. It is the actual power dissipated by the load.	2017, 2022
reactive power (Q).	A measure of the energy exchange between the source and the reactive part of the load. The unit is the volt-ampere reactive (VAR).	2017, 2022
apparent power (S).	The product of the rms values of voltage and current.	2017, 2022
Complex Power (S).	The product of the rms voltage phasor and the complex conjugate of the rms current phasor. Its real part is P and its imaginary part is Q.	External (Alexander)
power factor (pf).	The cosine of the phase difference between voltage and current: $pf=\cos ({\theta }_v-{\theta }_i)$. It is also the ratio of real power to apparent power.	2018, 2024
What is power triangle?	A graphical representation where the apparent power S, real power P, and reactive power Q form a right triangle.	2017, External (Alexander)
Power Factor Correction.	The process of increasing the power factor without altering the voltage or current to the original load.	External (Alexander)

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6. AC Resonance and Frequency Response

Definition/Statement	Description/Actual Text	Year(s) of Appearance
resonance.	That frequency at which the imaginary part of a transfer function vanishes. For RLC circuits, it is the state where the frequency ${\omega }_0=1/\sqrt{LC}$.	2016, 2019, External (Alexander)
What is Quality factor, Q?	A measure of the selectivity (or “sharpness” of resonance) of the circuit. It is the ratio of the resonant (angular) frequency to the bandwidth: $Q={\omega }_0/B$.	2017, 2022, 2023, External (Alexander)
Bandwidth (B).	The frequency band between half-power frequencies: $B={\omega }_2-{\omega }_1$.	External (Alexander)
Resonant Frequency (${\omega }_0$).	The frequency at which the imaginary part of a transfer function vanishes. For series and parallel RLC circuits, ${\omega }_0=1/\sqrt{LC}$.	External (Alexander)
Half-power frequencies (${\omega }_1,{\omega }_2$).	Those frequencies at which the power dissipated is one-half of that dissipated at the resonant frequency.	External (Alexander)
Filter.	A circuit designed to pass a band of frequencies and reject others.	External (Alexander)
Transfer Function H($\omega$).	The frequency-dependent ratio of a phasor output $Y(\omega )$ to a phasor input $X(\omega )$, assuming zero initial conditions.	External (Alexander)

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7. Three Phase (3- $\Phi$ ) Systems

Definition/Statement	Description/Actual Text	Year(s) of Appearance
balanced $3\Phi$ system.	A balanced three-phase system is one in which all three phase voltages (or currents) have equal magnitude and are separated by exactly 120° phase difference.	2016, 2018, 2019
unbalanced $3\Phi$ system.	An unbalanced three-phase system is one where phase voltages or currents are unequal in magnitude and/or do not maintain 120° phase spacing.	2016, 2019
phase sequence.	Phase sequence is the order in which the phase voltages reach their maximum (or zero-crossing) values.	2016, 2018, 2019

~ Nakib 2409007