What is the difference between alternating current (AC) and direct current (DC) and give an aviation example of each.

• A. DC flows in one direction; AC periodically reverses direction. Example: aircraft battery (DC) and alternator-generated electrical power (AC).
• B. AC flows in one direction; DC reverses direction. Example: aircraft battery (DC) and alternator-generated electrical power (AC).
• C. Both flow the same direction; examples: generator (AC) and battery (DC).
• D. DC changes direction rapidly; examples: inverter (DC) and rectifier (AC).

Answer: (A)