Chapter 1: Unit's associated with basic electrical circuits. Flashcards
(14 cards)
Define an electric current.
Electric current is the rate of movement of change.
State the symbol for electric current and the unit.
Symbol: I
Unit: Ampere
State the 3 main effects of electric current.
-Magnetic effect
-Heating effect
-Chemical effect
List examples of the magnetic effect.
-Bells
-Relays
-Motors
-Generators
-Transformers
-Telephones
List examples of the heating effect
-Cookers
-Water heaters
-Electric fires
-Irons
-Furnaces
-Kettles
-Soldering irons
List examples of the chemical effect
-Primary and secondary cells
-Electroplating
Describe direct current
Direct current is one that flows in one direction only around a circuit
Describe alternating current
Alternating current is one that constantly changes direction in a circuit, rising to a maximum in one direction before falling to zero and then rising to a maximum in the opposite direction.
Define a conductor
A material having a low resistance that allows electric current to flow through it.
List examples of conductors.
-Copper
-Aluminium
-Brass
-Platinum
-Silver
-Gold
-Carbon
Define an insulator.
A material having a high resistance that does not allow electric current to flow through it.
List examples of insulators.
-Plastic
-Rubber
-Glass
-Porcelain
-Air
-Paper
-Cork
-Mica
-Ceramics
-Certain oils
Define a semiconductor
A material with an electrical conductivity between that of a conductor and an insulator, it is neither a good insulator nor a good conductor under ordinary conditions, but can be made to exhibit some of the properties of each.
List examples of semiconductors
-Silicon
-Germanium