upgrade
upgrade
📚AP Physics C: E&M Unit 11 Vocabulary

80 essential vocabulary terms and definitions for Unit 11 – Electric Circuits

Study Unit 11
Practice Vocabulary
📚Unit 11 – Electric Circuits
Topics

📚Unit 11 – Electric Circuits

11.1 Electric Current

TermDefinition
chargeA fundamental property of matter that causes objects to experience forces in electric fields; can be positive or negative.
charge carrierParticles, typically electrons, that carry electric charge and constitute electric current in a conductor.
conductorA material that allows electric charge to move through it, with resistivity that typically increases with temperature.
conventional currentThe direction of current defined as the direction in which positive charge would move through a circuit.
currentThe flow of electric charge through a conductor, measured as the amount of charge passing through a cross-section per unit time.
current densityThe amount of electric current flowing per unit cross-sectional area of a conductor; a vector quantity.
drift velocityThe average velocity at which charge carriers move through a conductor in response to an applied electric field.
electric fieldA vector field that represents the force per unit charge exerted on a test charge at any point in space due to a charge distribution.
electric potential differenceThe difference in electric potential energy per unit charge between two points in a circuit, measured in volts.
electromotive forceThe energy per unit charge provided by a source to move charge through a circuit; also called emf.
electronNegatively charged particles that are the primary charge carriers in most common electrical circuits.
resistivityA fundamental property of a material that quantifies how strongly the material opposes the motion of electric charge, depending on the material's atomic and molecular structure.

11.2 Electric Circuits

TermDefinition
circuit schematicA diagram representation used to describe and analyze electric circuits using standardized symbols.
closed circuitA circuit in which charges are able to flow through a complete path.
conventional currentThe direction of current defined as the direction in which positive charge would move through a circuit.
electric potential differenceThe difference in electric potential energy per unit charge between two points in a circuit, measured in volts.
electrical loopA closed path in a circuit through which electric charge can flow.
open circuitA circuit in which charges are not able to flow due to a break in the path.
short circuitA circuit in which charges are able to flow with no change in potential difference.

11.3 Resistance, Resistivity, and Ohm's Law

TermDefinition
conductorA material that allows electric charge to move through it, with resistivity that typically increases with temperature.
cross-sectional areaThe area of the surface perpendicular to the direction of current flow through a conductor.
currentThe flow of electric charge through a conductor, measured as the amount of charge passing through a cross-section per unit time.
electric potential differenceThe difference in electric potential energy per unit charge between two points in a circuit, measured in volts.
Ohm's lawA fundamental relationship stating that current through a conductor is directly proportional to the potential difference across it and inversely proportional to its resistance, expressed as I = ΔV/R.
ohmic materialsMaterials that obey Ohm's law and maintain constant resistance regardless of the current flowing through them.
resistanceThe opposition to the flow of electric current in a circuit, measured in ohms (Ω).
resistivityA fundamental property of a material that quantifies how strongly the material opposes the motion of electric charge, depending on the material's atomic and molecular structure.
resistorA circuit element that dissipates electrical energy and opposes the flow of current, characterized by resistance R.
thermal energyEnergy dissipated in the form of heat when electrical energy is converted within a circuit element.
uniform geometryA resistor with constant cross-sectional area and composition throughout its length.

11.4 Electric Power

TermDefinition
circuit elementA component in an electric circuit, such as a resistor or lightbulb, through which current flows and across which a potential difference exists.
currentThe flow of electric charge through a conductor, measured as the amount of charge passing through a cross-section per unit time.
electric potential differenceThe difference in electric potential energy per unit charge between two points in a circuit, measured in volts.
energy transferThe movement of energy from one location, system, or form to another within an electric circuit.
powerThe rate at which energy is transferred, converted, or dissipated by a circuit element, measured in watts.
resistanceThe opposition to the flow of electric current in a circuit, measured in ohms (Ω).
thermal energyEnergy dissipated in the form of heat when electrical energy is converted within a circuit element.

11.5 Compound Direct Current Circuits

TermDefinition
ammeterAn instrument used to measure electric current at a specific point in a circuit.
currentThe flow of electric charge through a conductor, measured as the amount of charge passing through a cross-section per unit time.
electric potential differenceThe difference in electric potential energy per unit charge between two points in a circuit, measured in volts.
emfThe electromotive force; the potential difference a battery would supply if it were ideal, measured across the terminals when there is no current flowing.
equivalent resistanceThe single resistance value that can replace a combination of resistors in a circuit, producing the same effect on current and voltage.
ideal ammeterA theoretical ammeter with zero resistance that measures current without affecting the circuit.
ideal batteryA theoretical battery with negligible internal resistance that maintains a constant potential difference regardless of the current flowing through it.
ideal voltmeterA theoretical voltmeter with infinite resistance that measures potential difference without allowing charge to flow through it.
ideal wiresTheoretical wires with negligible resistance that do not affect the potential difference in a circuit.
internal resistanceThe resistance within a battery that reduces the potential difference available to the external circuit when current flows through the battery.
nonideal ammeterA real ammeter with some resistance that can alter the properties of the circuit being measured.
nonideal batteryA real battery that has internal resistance and therefore experiences a reduction in terminal voltage when current flows through it.
nonideal voltmeterA real voltmeter with finite resistance that can alter the properties of the circuit being measured.
parallel connectionA circuit configuration in which circuit elements are connected along multiple paths, allowing charge to flow through more than one route with the same potential difference across each path.
resistanceThe opposition to the flow of electric current in a circuit, measured in ohms (Ω).
resistive wiresWires in a circuit that have measurable resistance and can affect the overall circuit behavior.
series connectionA circuit configuration in which circuit elements are connected one after another, so that charge must pass through each element sequentially with no alternative paths available.
terminal voltageThe potential difference measured across the terminals of a battery, which equals the emf minus the voltage drop due to internal resistance when current is flowing.
voltmeterAn instrument used to measure the electric potential difference between two points in a circuit.

11.6 Kirchhoff's Loop Rule

TermDefinition
circuit elementA component in an electric circuit, such as a resistor or lightbulb, through which current flows and across which a potential difference exists.
closed loopA complete path in a circuit that starts and ends at the same point, allowing current to flow continuously.
conservation of energyThe principle that the total energy in an isolated system remains constant, with energy transforming between different forms but never being created or destroyed.
electric potentialThe electric potential energy per unit charge at a point in space, describing the work done per unit charge to move a test charge from a reference point to that location.
electric potential differenceThe difference in electric potential energy per unit charge between two points in a circuit, measured in volts.
Kirchhoff's loop ruleA principle stating that the sum of potential differences across all circuit elements in a single closed loop must equal zero, based on conservation of energy.

11.7 Kirchhoff's Junction Rule

TermDefinition
conservation of electric chargeThe principle that the total electric charge in an isolated system remains constant over time.
currentThe flow of electric charge through a conductor, measured as the amount of charge passing through a cross-section per unit time.
junctionA point in a circuit where two or more conductors meet, allowing current to split or combine.
Kirchhoff's junction ruleA principle stating that the total amount of electric charge entering a junction per unit time must equal the total amount of charge exiting that junction per unit time, based on conservation of electric charge.

11.8 Resistor-Capacitor (RC) Circuits

TermDefinition
asymptotic approachThe behavior of a quantity that approaches a final value over time but never quite reaches it, as seen in RC circuit charging and discharging.
capacitor in parallelCapacitors connected with their plates connected together, where each capacitor experiences the same voltage.
capacitor in seriesCapacitors connected end-to-end in a single path, where the same charge accumulates on each capacitor plate.
charging capacitorA capacitor in a circuit that is accumulating charge, with its charge increasing from zero toward a maximum value over time.
conservation of electric chargeThe principle that the total electric charge in an isolated system remains constant over time.
differential equationA mathematical equation that relates a function to its derivatives, used to describe how quantities change over time.
discharging capacitorA capacitor in a circuit that is losing charge, with its charge decreasing from a maximum value toward zero over time.
electric potential energy stored in the capacitorThe energy stored in the electric field between the capacitor plates, which changes as the capacitor charges or discharges.
equivalent capacitanceThe single capacitance value that can replace a combination of capacitors in a circuit while maintaining the same electrical behavior.
Kirchhoff's loop ruleA principle stating that the sum of potential differences across all circuit elements in a single closed loop must equal zero, based on conservation of energy.
potential difference across a capacitorThe voltage between the plates of a capacitor, which changes over time during charging and discharging and reaches a constant value at steady state.
RC circuitA circuit containing a resistor and capacitor in combination, where the charge and current change over time as the capacitor charges or discharges.
steady stateA condition reached after a long time interval where circuit quantities no longer change with time.
time constantA characteristic parameter that measures how quickly a circuit reaches steady state, calculated differently for RC and LR circuits.