Alternating current- electric current that repeatedly reverse direction, twice each cycle.
Ampere-SI unit of electric current, a flow one coulomb of charge per second is one ampere.
Diode - An electronic device that restricts current flow in a single direction in an electric circuit,
Direct current - Electric current whose flow of charge is always in one direction.
Electric current - A flow of electric charge; measured in amperes.
Electric power - The rate at which electrical energy is converted into another form, such as light, heat, or mechanical energy.
Ohm - The SI unit of electric resistance, one Ohm is the resistance of a device that draws 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 impressed across the circuit, and is inversely proportional to resistance of the circuit,
Potential Difference - In electric potential 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 difference.