Alternating current- Electric current that repeatedly reverses direction twice each cycle. Usually at 60 cycles per second, or hertz.
ampere- SI unit of electric current. A flow of one coulomb of charge per second is one ampere (symbol A).
Diode- An electric device that restricts current to flow in a single direction in an electric circuit.
Direct current- Electric current whose flow of charge is all in one direction
electric current- The flow of electric charge; measured in amperes (C/S).
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 in ohs (symbol
Ω).
OHM- The SI unit of electric resistance. One ohm (symbol
Ω) is the resistance of a devise draw a current of one ampere when a voltage of one volt is impressed across it.
Ohm's law- The statement that the current in a circuit is directly proportional to the voltage across the circuit, and is inversely proportional 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 and will continue until both points reach a common potential.
Voltage source- A device, such as a dry cell or generator, that provides a potential differences.