A full cycle of an alternating current is defined as the interval from which point to which point on the waveform?

• A. Zero crossing to zero crossing
• B. Trough to trough
• C. Peak to peak
• D. Midpoint to midpoint

Answer: (C)

A full cycle is the time it takes for the waveform to complete one complete repetition, returning to the same phase. The peak is a distinct, recurring point in each cycle, so from one peak to the next peak the waveform has progressed through a full 360 degrees of phase. That makes peak-to-peak a clear, unambiguous way to mark one complete cycle. Other markers, like zero crossings or troughs, can also define a cycle but often require specifying the direction or slope to avoid ambiguity, whereas peak-to-peak directly captures a full repetition without extra qualifiers.