How is alternating current (AC) generated?   Please provide a more advanced-level answer. 

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crmhaske eNotes educator| Certified Educator

Alternating current differs from direct current in that the current does not always travel in the same direction.  Rather, the direction of the flow of electrical charge changes on a periodic basis.  AC generators produce alternating currents by placing a rotating conductor, called an armature, between two magnetic poles.  When the conductor cuts the magnetic flux lines created between the two magnetic poles a voltage is created.  The direction the conductor crosses the magnetic flux lines affects the charge: one direction creates a positive charge, while the other will create a negative charge.  Slip rings on the ends of the wires of the conductor move against brushes as the conductor rotates allowing the current to be transmitted into the AC circuit.