Current Electricity

Vocabulary flashcards based on the concepts covered in the Current Electricity lecture.

Electric Current

The flow of charged particles through a conductive pathway, primarily measured in amperes.

Ampere

The SI unit of electric current, defined as one coulomb of charge flowing per second.

Direct Current (DC)

Electric current that flows steadily in one direction, often produced by batteries.

Alternating Current (AC)

Electric current that periodically reverses direction, commonly produced by generators.

Conventional Current

The assumed direction of current flow, from the positive terminal to the negative terminal of a battery.

Potential Difference (p.d.)

The difference in electric potential energy between two points in a circuit, measured in volts.

Electromotive Force (e.m.f.)

The energy supplied by a source per unit charge to maintain a steady current in an electric circuit.

Ohm's Law

The relationship stating that the current through a conductor is directly proportional to the voltage across it, assuming constant temperature.

Resistance

The opposition to the flow of electric current, measured in ohms.

Resistivity

A material's inherent resistance to current flow, defined per unit length and unit area, measured in ohm-meters.

Ammeter

An instrument used to measure the current in a circuit, connected in series.

Voltmeter

An instrument used to measure potential difference across a component in a circuit, connected in parallel.

Temperature Coefficient of Resistance

A measure of how much a material's resistance changes with temperature.

Current Flow

The movement of electric charge carriers (typically electrons) through a conductor.

Potential Energy

The energy per unit charge associated with the position of a charge within an electric field.

Coulomb

The unit of electric charge, equivalent to the charge transported by a constant current of one ampere in one second.

Milliampere (mA)

A submultiple of the ampere, where 1 mA = 10^-3 A.

Microampere (μA)

A submultiple of the ampere, where 1 μA = 10^-6 A.

Ohmic Devices

Materials that obey Ohm's law, where resistance remains constant regardless of voltage and current.

Non-Ohmic Devices

Materials that do not obey Ohm's law, displaying varying resistance under different conditions.

Graph of Resistance vs. Temperature

A graph showing how resistance changes with temperature, typically increasing for conductors.

Electrical Conduction in Metals

The process by which free electrons in metals move under the influence of an electric field, establishing current.

SI Unit of Voltage (Volt)

Defined as the potential difference that will move one joule of energy per coulomb of charge.

Charge Flow Equation

The equation relating charge, current, and time: Q = I × t.