Chapter 11: Electricity Vocabulary Flashcards

A set of vocabulary flashcards defining fundamental concepts, units, and laws in electricity based on Chapter 11 notes.

Electric Current

The rate of flow of electric charges, expressed as the amount of charge flowing through a particular cross-sectional area in unit time.

Electric Circuit

A continuous and closed path along which an electric current can flow.

Ampere

The SI unit of electric current, named after Andre-Marie Ampere; one ampere is defined as the flow of one coulomb of charge per second ($1\,A = 1\,C / 1\,s$).

Ammeter

An instrument used to measure electric current in a circuit, which is always connected in series.

Electric Potential Difference

The work done to move a unit charge from one point to another in a current-carrying electric circuit ($V = \frac{W}{Q}$).

Volt

The SI unit of electric potential difference, named after Alessandro Volta; defined as the potential difference between two points when $1\,J$ of work is done to move a charge of $1\,C$ ($1\,V = 1\,J\,C^{-1}$).

Voltmeter

An instrument used to measure the electric potential difference between two points in a circuit, which is always connected in parallel.

Ohm's Law

The rule formulated by Georg Simon Ohm stating that the potential difference $V$ across a metallic wire is directly proportional to the current $I$ flowing through it at a constant temperature ($V = IR$).

Resistance

The property of a conductor to resist the flow of charges through it, defined as $R = \frac{V}{I}$ and measured in ohms ($\Omega$).

Variable Resistance

A component used in an electric circuit to regulate or change current without altering the voltage source.

Rheostat

A device frequently used in electric circuits to change the resistance within the circuit.

Resistor

A conductor that has an appreciable resistance to retard the motion of electrons.

Electrical Resistivity

A characteristic property of a material measuring its fundamental resistance to electric current, defined by $R = \rho \frac{l}{A}$ and expressed in units of $\Omega\,m$.

Resistors in Series

A circuit configuration where resistors are joined end to end so that the same current flows through every component and total resistance is $R_s = R_1 + R_2 + R_3$.

Resistors in Parallel

A circuit configuration where resistors are connected across common points, splitting current according to branch resistances, with total resistance satisfying $\frac{1}{R_p} = \frac{1}{R_1} + \frac{1}{R_2} + \frac{1}{R_3}$.

Joule's Law of Heating

The law stating that the heat $H$ produced in a resistor is directly proportional to the square of current, resistance, and time ($H = I^2 R t$).

Fuse

A circuit safety device placed in series that protects appliances by melting and breaking the circuit when current exceeds a designated rating.

Electric Power

The rate at which electrical energy is dissipated or consumed in an electric circuit ($P = VI = I^2 R = \frac{V^2}{R}$), measured in watts ($W$).

Kilowatt Hour

The commercial unit of electric energy ($kW\,h$), equal to $3.6 \times 10^6\,J$.