Alternating Current
Alternating Current in a circuit moves back and forward very quickly with current flowing first in one direction and then in the other.
The electricity is not provided as a single, constant voltage like DC current , but rather as a wave, which increases a maximum value, then decreases to a minimum value, and repeats.
The flow of current moves back and forward extremely quickly, lightbulbs actually flicker slightly as the current move back and forware.
The image below shows 1 alternating current on a 60 hertz per second circuit.
Each wave back and forwards is called a cycle or hertz.
50 cycles or hertz per second is the standard frequency in Europe, while 60 Hertz is used in America.
The purpose of an Alternating current generator is to convert movement into electricity. A wire passing through a magnetic field causes electrons in that wire to move in one direction.
The animated image (left) shows an alternating current generator in action. As it moves from one side of the magnetic field to the other, the current changes direction.
Because the loop is spinning, it's moving across the field first in one direction and then in the other, which means that the flow of electrons keeps changing.
Because the electrons move in two different directions in a wave, the process is called alternating current.
Alternating current is the type of mains current that supplies residential housing. It is produced by huge generators in electric power stations.
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