Real and Ideal Sources

ELECTRICAL TERMINOLOGY Basic Electrical Theory Generally, electric current flow can be classified as one of two general types: Direct Current (DC) or Alternating Current (AC). A direct current flows continuously in the same direction. An alternating current periodically reverses direction. We will be studying DC and AC current in more detail later in this text. An example of DC current is that current obtained from a battery. An example of AC current is common household current. Real and Ideal Sources An ideal source is a theoretical concept of an electric current or voltage supply (such as a battery) that has no losses and is a perfect voltage or current supply. Ideal sources are used for analytical purposes only since they cannot occur in nature. A real source is a real life current or voltage supply that has some losses associated with it. Summary The important information contained in this chapter is summarized below. Terminology Summary Conductor - material with electrons loosely bound to its atoms or that permits free motion of large number of electrons Insulator - material with electrons tightly bound to its atoms; requires large amounts of energy to free electrons from its nuclei Resistor - material that conducts electricity, but opposes current flow Electron Current Flow - current flow from negative to positive potentials Conventional Current Flow - current flow from positive to negative potentials Direct Current - current flow continuously in the same direction Alternating Current - current flow periodically reverses direction Ideal Source - theoretical current or voltage supply with no losses Real Source - actual current or voltage supply with losses ES-01 Page 12 Rev. 0