Electric Currents and Resistance

These flashcards cover key terms and definitions related to electric currents and resistance.

Electric Current

The flow of electric charge, typically measured in Amperes (A), which is the rate of charge passing a given point.

Voltage

The difference in electric potential energy per unit charge between two points in an electric circuit, measured in volts (V).

Resistance

The opposition to the flow of electric current, measured in Ohms (Ω).

Ohm's Law

A fundamental principle stating that the current through a conductor between two points is directly proportional to the voltage across the two points, represented as V=IR.

Ampère

The unit of electric current in the International System of Units (SI), equivalent to one coulomb per second.

Direct Current (DC)

An electric current flowing in one direction only, commonly supplied by batteries.

Alternating Current (AC)

An electric current that reverses direction periodically, commonly supplied by power outlets.

Electrolyte

A substance that produces an electrically conducting solution when dissolved in a polar solvent, such as water.

Electromotive Force (EMF)

The electric potential generated by either a chemical reaction or a magnetic field, known for driving current in a circuit.

Drift Velocity

The average velocity that a charge carrier, such as an electron, attains due to an electric field.

Resistivity

A material's intrinsic resistance to current flow, typically represented by the symbol ρ, with units of Ohm-meters (Ω·m).

Power (Electrical)

The rate at which electrical energy is converted to another form of energy, calculated as P=VI, where P is power, V is voltage, and I is current.

Joule Effect

The conversion of electrical energy into heat energy when electric current passes through a conductor.

Semiconductor

A material that has conductivity between that of an insulator and that of a conductor; its conductivity can be modified by impurities or temperature.

Series Circuit

A circuit in which the components are connected one after another, so that the same current flows through all components.

Parallel Circuit

A circuit in which the components are connected across common points or junctions, allowing multiple paths for current.

Conductivity

The ability of a material to conduct electric current, the reciprocal of resistivity.

Diode

A semiconductor device that allows current to flow in one direction only.

Thermistor

A type of resistor whose resistance changes significantly with temperature.

Flux Density

The amount of electric charge per unit area, used to understand current flow in conductors.

Electric Field

A field around charged particles that exerts a force on other charged particles.