Basic Electricity: Quantities, Charges, Circuits, and Measurements

Vocabulary practice flashcards covering fundamental electrical concepts, units and notations, electrostatic discharge (ESD) safety, multimeter operation, atomic charge, and basic circuit components.

Scientific Notation

A method for expressing very large and very small numbers as a number between one and ten multiplied by a power of ten.

Engineering Notation

A specialized form of scientific notation in which numbers are expressed with one, two, or three digits to the left of the decimal point multiplied by a power of ten that is a multiple of $3$.

Metric Prefix

A symbol that is used to replace the power of ten in numbers expressed in engineering notation.

Static Electricity

An unbalanced electrical charge that is not moving, representing the accumulation of excess charge on the surface of an object.

Control Bonding

Conductive straps installed to electrically interconnect aircraft control surfaces to keep them at the same electrical potential.

Static Dischargers

Wicks or pins mounted on aircraft trailing edges that provide a low-resistance path to dissipate accumulated static charge safely into the air.

Static Lines

Conductive grounding cables connected during aircraft fueling in a specific safety sequence: Aircraft to Ground $\rightarrow$ Truck to Ground $\rightarrow$ Aircraft to Truck.

Voltmeter

A multimeter configuration used to measure electrical potential difference across a component by connecting the meter in parallel with the circuit.

Ohmmeter

A multimeter configuration used to measure resistance across an isolated component after all electrical power has been removed from the circuit.

Ammeter

A multimeter configuration used to measure current flow by opening the circuit path and inserting the meter in series.

Power Rails

The outer columns marked with $(+)$ and $(-)$ along the sides of a breadboard used for distributing power, which are not electrically connected across opposite sides of the board.

Atom

The smallest particle of an element that retains the chemical and physical characteristics of that element.

Electron

The basic subatomic particle of negative electrical charge, possessing an elementary charge of approximately $-1.602 \times 10^{-19}\,\text{C}$.

Proton

The basic subatomic particle possessing a positive unit of electrical charge, located within the nucleus of an atom.

Ion

An atom that has gained or lost one or more electrons and is no longer electrically neutral; includes positively charged cations and negatively charged anions.

Free Electron

A valence electron that has broken away from the outer orbit of its parent atom and is free to move between atoms, making electric current possible.

Coulomb (C)

The standard SI unit of electrical charge, equal to the total charge possessed by $6.24 \times 10^{18}$ electrons.

Coulomb’s Law

A principle stating that the electrostatic force between two charged bodies is directly proportional to the product of their charges and inversely proportional to the square of the distance between them.

Electric Shock

A dangerous physiological effect and physical sensation resulting from electrical current passing through the human body.

Let-Go Threshold

The maximum current level at which a person holding a live conductor can voluntarily release it; $99\%$ of adults cannot let go at a current greater than $22\,\text{mA}$.

Electrical Burns

Internal physiological burns caused by current flowing through body tissues, typically occurring below the skin surface.

Voltage (E)

The electrical potential difference between two points in a circuit that provides the electromotive force driving current flow.

Volt (V)

The unit of measurement for voltage and electrical potential difference, defined as one joule of energy per coulomb of charge ($1\,\text{V} = 1\,\text{J/C}$).

Current (I)

The rate of flow of electrical charge past a given point in an electrical circuit over time ($I = \frac{Q}{t}$).

Ampere (A)

The SI unit of electrical current, defined as one coulomb of charge moving past a cross-sectional point in one second ($1\,\text{A} = 1\,\text{C/s}$).

Power (W)

The rate at which electrical energy is used, transferred, or transformed, measured in watts ($\text{W}$).

Closed Circuit

An electrical circuit configuration with an uninterrupted path that permits current to flow continuously.

Open Circuit

An electrical circuit configuration that has a break or discontinuity in its conducting path, preventing the flow of current.

Short Circuit

An unintended, low-resistance connection between two points in a circuit that diverts electrical current away from the intended path.

Ground

The common reference point or return path of zero electrical potential in a circuit.

Load

A circuit component, such as a resistor or device, that draws electrical current from a power source to perform work.

Battery

A direct-current voltage source represented schematically by alternating long and short parallel lines denoting positive and negative terminals.

Fuse and Circuit Breaker

Protective circuit components designed to break the current path when current exceeds a predetermined rating; automatic reset types are never used in aviation.

Switch

An electromechanical control device used to make or break electrical circuit paths, classified by poles and throws (e.g., SPST, SPDT, DPST, DPDT).

American Wire Gauge (AWG)

A standardized wire sizing system used in aviation and electronics where wire diameter and cross-sectional area correspond to specific numerical gauge ratings.