Sections

Key Terms
# Key Terms

- alternating current
- electric current whose direction alternates back and forth at regular intervals

- ampere
- unit for electric current; one ampere is one coulomb per second ($1\text{\hspace{0.17em}}\text{A}=1\text{\hspace{0.17em}}\text{C/s}$)

- circuit diagram
- schematic drawing of an electrical circuit including all circuit elements, such as resistors, capacitors, batteries, and so on

- conventional current
- flows in the direction that a positive charge would flow if it could move

- direct current
- electric current that flows in a single direction

- electric circuit
- physical network of paths through which electric current can flow

- electric current
- electric charge that is moving

- electric power
- rate at which electric energy is transferred in a circuit

- equivalent resistor
- resistance of a single resistor that is the same as the combined resistance of a group of resistors

- in parallel
- when a group of resistors are connected side by side, with the top ends of the resistors connected together by a wire and the bottom ends connected together by a different wire

- in series
- when elements in a circuit are connected one after the other in the same branch of the circuit

- nonohmic
- material that does not follow Ohm’s law

- ohmic
- material that obeys Ohm’s law

- Ohm’s law
- electric current is proportional to the voltage applied across a circuit or other path

- resistance
- how much a circuit element opposes the passage of electric current; it appears as the constant of proportionality in Ohm’s law

- resistor
- circuit element that provides a known resistance

- steady state
- when the characteristics of a system do not change over time