Key Terms

Key Terms

alternating current
electric current whose direction alternates back and forth at regular intervals
unit for electric current; one ampere is one coulomb per second (1A=1C/s1A=1C/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
material that does not follow Ohm’s law
material that obeys Ohm’s law
Ohm’s law
electric current is proportional to the voltage applied across a circuit or other path
how much a circuit element opposes the passage of electric current; it appears as the constant of proportionality in Ohm’s law
circuit element that provides a known resistance
steady state
when the characteristics of a system do not change over time