Baguio College of Technology - Basic Electronics: Key Terms (Electricity, Atoms, Units)

Vocabulary flashcards covering key terms from electricity, atomic structure, and electrical quantities described in the notes.

Alternating current (AC)

An electric current that reverses its direction many times a second at regular intervals.

Ampere

A unit of electric current equal to the flow of one coulomb per second.

Atom

The basic unit of a chemical element; consists of a nucleus and electrons orbiting.

Atomic number

The number of protons in the nucleus of an atom.

Circuit

Interconnection of components to provide an electrical path between two or more components.

Conductor

A material that conducts electric current very well.

Coulomb

The SI unit of electric charge, equal to the quantity of electricity conveyed in one second by a current of one ampere.

Current

Measured in amperes; the flow of electrons through a conductor.

Dielectric

An insulating material between two plates where an electrostatic field exists.

Direct current (DC)

Current that flows in only one direction.

Electron

The smallest subatomic particle of negative charge that orbits the nucleus of an atom.

Electron flow

Electrical current produced by the movement of free electrons toward a positive terminal.

Free electron

Electrons that are not attached to the nucleus and are free to move.

Insulator

A substance that resists electricity.

Ion

An atom or molecule that has a net electrical charge.

Molecules

An electrically neutral group of two or more atoms held together by chemical bonds.

Neutron

A subatomic particle.

Nucleus

The very dense central region of an atom.

Ohm

Unit of resistance, symbolized by the Greek capital letter omega (Ω).

Potential difference

Voltage difference between two points which will cause current to flow in a closed circuit.

Proton

A subatomic particle, symbol p or p+.

Resistance

Opposition to current flow and dissipation of energy in the form of heat.

Semiconductor

An element that is between a good conductor and a good insulator, lying between the two.

Siemens

Unit of electric conductance (symbol: S).

Static electricity

An imbalance of electric charges within or on the surface of a material.

Volt

Derived unit for electric potential, voltage, and electromotive force (symbol: V).

Negative polarity

Charge associated with electrons; negative.

Positive polarity

Charge associated with protons; positive.

Neutral condition

A state where the number of protons equals the number of electrons, so there is no net charge.

Battery

A device that stores chemical energy and can separate charges to produce electrical energy.

Area

Square metre (m²).

Volume

Cubic metre (m³).

Frequency

Hertz (Hz) — cycles per second.

Density

Kilogram per cubic metre (kg/m³).

Velocity

Metre per second (m/s).

Acceleration

Metre per second squared (m/s²).

Force

Newton (N) — unit of force.

Torque

Newton-metre (N·m) — unit of torque.

Pressure

Newton per square metre (N/m²).

Work

Joule (J) — energy work units (N·m).

Power

Watt (W) — rate of doing work or energy transfer.

Charge

Coulomb (C) — quantity of electricity.

Electric field strength

Volt per metre (V/m).

Capacitance

Farad (F).

Inductance

Henry (H).

Magnetic flux

Weber (Wb).

Magnetic field strength

Ampere per metre (A/m).

Magnetic flux density

Tesla (T).

Magnetomotive force

Ampere (A) as the MMF unit.

Luminous flux

Lumen (lm).

Illumination

Lux (lx).

Valence electron

An outer shell electron that can participate in bonding.

Conductor vs Insulator vs Semiconductor

Conductor conducts electricity well; insulator resists; semiconductor lies between.