Final answer:
When a frequency of 60 Hz is used, alternating current flows in one direction for 1/120th of a second.
Step-by-step explanation:
When a frequency of 60 Hz is used, alternating current (AC) flows in one direction for a duration of 1/120th of a second. This is because in one full cycle of AC, there are two half cycles. In each half cycle, the current flows in one direction for an equal amount of time before reversing its direction.
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