Alternating(AC)- Electric current that repeatedly reverses direction, twice each cycle. Usually at 60 cycles per second, or Hertz (HZ), in North America, or 50 Hertz elsewhere.
Ampere (AM-Peer)- SI unit of electric current. A flow of one coulomb of change per second, is one ampere (symbol A).
Diode (DI-od)- An electronic device that restricts current to flow in a single direction in an electric circuit.
Direct current- Electric current whose flow of charge is always in one direction
Electric currents- The flow of electric change measured in Amperes.
Electric Power- The rate at which electric energy is converted into another form, such as light,heat, or Mechanical energy.
Electric Resistance- The resistance of a material to the flow of electric current through it measured it ohms.
Ohms- The SI unit of electric resistance. One ohms is the resistance of a device that draws a current of one ampere when a voltage of one volt is impressed across it.
Ohms Law- The statement that the current in a circuit is directly proportional to the voltage impressed across the circuit, & is inversely proportion to the resistance of the circuit.
Potential Difference- The difference in electric potential (voltage) between two points. Free charge flows when there is a difference, & will continue until both points reach a common potential.
Voltage Source- A device, such as a dry cell or generator, that provides a potential difference.