Alternating Current: an electric current that reverses its direction many times a second at regular intervals, typically used in power supplies
Ampere: a unit of electric current equal to a flow of one coulomb per second
Diode: a semiconductor device with two terminals, typically allowing the flow of current in one direction only.
Direct Current: an electric current flowing in one direction only
Electric Current: An electric current is a flow of electric charge. In electric circuits this charge is often carried by moving electrons in a wire. It can also be carried by ions in an electrolyte, or by both ions and electrons such as in a plasma.
Electric Power: Electric power is the rate at which electric energy is transferred by an electric circuit. The SI unit of power is the watt, one joule per second.
Electric Resistance: Resistance is an electrical quantity that measures how the device or material reduces the electric current flow through it. The resistance is measured in units of ohms (Ω).
Ohm: the SI unit of electrical resistance, expressing the resistance in a circuit transmitting a current of one ampere when subjected to a potential difference of one volt.
Ohms Law: Ohm's law states that the current through a conductor between two points is directly proportional to the potential difference across the two points. Introducing the constant of proportionality, the resistance, one arrives at the usual mathematical equation that describes this relationship:
Potential Difference: the energy possessed by a body by virtue of its position relative to others, stresses within itself, electric charge, and other factors.
Voltage Source: A Voltage source is a two terminal device which can maintain a fixed voltage. An ideal voltage source can maintain the fixed voltage independent of the load resistance or the output current.