FE Electrical Glossary
Key terms and definitions for the Electrical and Computer Engineering exam.
Impedance
The total opposition to current flow in an AC circuit, combining resistance and reactance. Expressed as a complex number in ohms with magnitude and phase angle.
Capacitance
The ability of a component to store electrical energy in an electric field. Measured in farads, equal to the charge stored divided by the voltage across the capacitor.
Inductance
The ability of a component to store electrical energy in a magnetic field. Measured in henrys, it opposes changes in current and is proportional to the number of turns squared in a coil.
Thevenin Equivalent
A simplified representation of a linear circuit as a single voltage source in series with a single resistance. Used to analyze the behavior of one portion of a circuit.
Transfer Function
The ratio of the Laplace transform of the output to the Laplace transform of the input for a linear time-invariant system, assuming zero initial conditions.
Phasor
A complex number representing the amplitude and phase of a sinusoidal signal. Used to convert differential equations in AC circuit analysis into algebraic equations.
Kirchhoff Voltage Law
The sum of all voltages around any closed loop in a circuit equals zero. A fundamental law based on conservation of energy used in circuit analysis.
Kirchhoff Current Law
The sum of all currents entering a node equals the sum of all currents leaving that node. A fundamental law based on conservation of charge used in circuit analysis.
Boolean Algebra
A branch of mathematics that deals with binary variables and logic operations (AND, OR, NOT). Forms the foundation of digital circuit design and computer logic.
Bode Plot
A pair of logarithmic graphs (magnitude and phase) showing a system frequency response. Used to analyze stability, bandwidth, and gain margin of control systems.
Op-Amp
An operational amplifier, a high-gain differential voltage amplifier with high input impedance and low output impedance. Used in inverting, non-inverting, summing, and integrator circuit configurations.
Power Factor
The ratio of real power to apparent power in an AC circuit, equal to the cosine of the phase angle between voltage and current. A factor of 1 indicates purely resistive load.
Norton Equivalent
A simplified representation of a linear circuit as a single current source in parallel with a single resistance. Mathematically related to the Thevenin equivalent by source transformation.
Diode
A semiconductor device that allows current to flow primarily in one direction. In forward bias it conducts with a small voltage drop; in reverse bias it blocks current flow.
Flip-Flop
A bistable digital circuit element that stores one bit of data. Types include SR, D, JK, and T flip-flops, each with different input configurations and triggering behavior.
Laplace Transform
A mathematical operation that converts a time-domain function into a complex frequency-domain function. Essential for solving linear differential equations in circuit and control system analysis.
Resonance
The condition in an RLC circuit where the inductive and capacitive reactances are equal, causing the impedance to be purely resistive and the current to reach its maximum value.