AP Physics C E&M: Direct-Current Circuits

ammeter

instrument that measures current

electromotive force AKA emf, ℰ

energy produced per unit charge, drawn from a source that produces an electrical current

equivalent resistance

resistance of a combination of resistors; it can be thought of as the resistance of a single resistor
that can replace a combination of resistors in a series and/or parallel circuit

internal resistance

amount of resistance to the flow of current within the voltage source

junction rule

sum of all currents entering a junction must equal the sum of all currents leaving the junction

Kirchhoff's rules

set of two rules governing current and changes in potential in an electric circuit

loop rule

algebraic sum of changes in potential around any closed circuit path (loop) must be zero

potential difference, ΔV

difference in electric potential between two points in an electric circuit, measured in volts

RC circuit

circuit that contains both a resistor and a capacitor

terminal voltage, ΔV

potential difference measured across the terminals of a source when there is no load attached

voltmeter

instrument that measures voltage

energy, internal

2 fundamental parts of all potential difference sources:
1.) source of electrical ___________
2.) an ___________ resistance

chemical reactions

The work done on electrons to move them to the positive terminal is powered by energy from ___________ in battery.

ideal battery

An emf source that maintains a constant terminal voltage, independent of the current between the two terminals. It has no internal resistance.

chemicals, terminals

The emf of a battery is determined by a combination of ___________ and the makeup of the ___________.

increases

Internal resistance generally ___________ as a battery is depleted. It may depend on magnitude and direction of current through emf sources.

resistor, connected

The equivalent resistance of a circuit depends on the ___________ of each resistor and how they are ___________.

parallel combination

components in a circuit arranged with one side of each component connected to one side of the circuit and the other sides of the components connected to the other side of the circuit

series combination

components in a circuit arranged in a row one after the other in a circuit

series, parallel

Resistors in ___________ have the same current flowing through them. Resistors in ___________ have the same potential difference across them.

junction

A connection of 3 or more wires.

junction rule

The sum of all currents entering a junction must equal the sum of all currents leaving the junction.

loop rule

The algebraic sum of changes in potential around any closed circuit path must be zero.

increase, decrease

Batteries ___________ electric potential from negative to postive terminals. Reesistors ___________ potential.

parallel, series

Voltmeters must be connected in ___________. Ammeters must be connected in ___________.

capacitor

In an RC circuit, a ___________ is either uncharged, charging, charged, or discharging.

differential

Analyzing RC circuits with the loop rule yields ___________ equations that can be used to find charge on the capacitor, current, and potential difference as a function of time.

time constant, τ

quantity defined for an RC circuit that is a fixed quantity for a certain resistor and capacitor.