Current, Resistance, Voltage, and Electronic Components

Comprehensive vocabulary flashcards covering the principles of electricity, circuit types, and electronic components such as diodes, capacitors, transformers, and inductors.

Electric current

The flow of electrons inside wires that occurs when a device is plugged into a socket.

Voltage

The electrical push or pressure behind the flow of current, also referred to as potential difference, measured in Volts ($V$).

Current

The rate of flow of charge in a circuit, measured in Amperes ($A$).

Ammeter

The instrument used to measure electric current, which must be connected in series.

Current Formula

The mathematical expression $i = \frac{Q}{t}$ where $i$ is current, $Q$ is charge ($C$), and $t$ is time ($s$).

Voltmeter

The instrument used to measure voltage, which is connected in parallel.

Resistance

The measure of how much a material opposes the flow of current, measured in Ohms ($\Omega$).

Ohmmeter

The instrument used to measure electrical resistance ($\Omega$).

Ohm’s Law

The statement that current is directly proportional to voltage and inversely proportional to resistance, expressed as $V = i \times R$.

Electronic Circuit

A closed pathway or loop consisting of components connected by conductive wires through which electric current flows.

Resistors

Building blocks of a circuit designed to limit current flow.

Capacitors

Components that store electrical energy in an electric field between two conductive plates separated by a dielectric.

Conductors

Materials or components that allow electric current to pass through them.

Series Circuit

A circuit with a single pathway where components are connected end-to-end and if one component fails, the entire circuit stops.

Parallel Circuit

A circuit with multiple pathways where the voltage remains the same across all components and other branches continue working if one fails.

Combination Circuit

A circuit that integrates both series and parallel connections to balance current distribution and voltage regulation.

Diode

An electronic component acting as a one-way valve that allows electricity to flow in one direction but restricts it in the opposite direction.

Anode ($+$)

The positive terminal of a diode where electric current enters.

Cathode ($-$)

The negative terminal of a diode where current exits, typically marked with a stripe.

P-N Junction

The interface in a diode where P-type and N-type semiconductors meet, forming a depletion region that blocks reverse current.

Rectifiers

Diodes used to convert alternating current ($AC$) into direct current ($DC$).

Zener Diode

A type of diode that allows reverse current after reaching a specific breakdown voltage, used for voltage regulation.

Photodiode

A diode that operates in reverse bias and converts light into electrical current.

Dielectric

The insulating material that separates the two conductive plates within a capacitor.

Ceramic Capacitor

A small, inexpensive capacitor best suited for high-frequency circuits like radios and mobile devices.

Electrolytic Capacitor

A polarized capacitor with larger capacitance commonly used in power supplies and amplifiers.

Supercapacitor

A component capable of storing significantly more energy than ordinary capacitors, used in electric vehicles and renewable energy storage.

Alternating Current ($AC$)

Electric current that changes direction many times per second, commonly supplied to homes and buildings.

Electromagnetic Induction

The process of producing electricity using a changing magnetic field without direct contact.

Transformer

A static electrical device that transfers energy between circuits through electromagnetic induction, changing voltage while maintaining the same frequency.

Step-Up Transformer

A transformer with more turns in the secondary coil than the primary, used to increase voltage for long-distance transmission.

Step-Down Transformer

A transformer with fewer turns in the secondary coil than the primary, used to decrease voltage for safe home use.

Inductor

A coil of wire that stores energy in a magnetic field when current flows and resists changes in current.

Inductance

The property of an inductor to resist changes in current, measured in the SI unit Henry ($H$).

Toroidal inductor

An inductor wound around a ring-shaped core that is efficient and reduces electromagnetic interference.