The return current of nonlinear loads can cause ___ of the voltage waveform.

• A. Voltage transients
• B. Mitigation
• C. Harmonic distortion
• D. Apparent power

Answer: (C)

Nonlinear loads draw current that isn’t a pure sine wave, so the return current contains harmonics. When those harmonic currents flow through the source and its impedances, they create voltage drops at the harmonic frequencies. The result is a voltage waveform that becomes distorted, with additional harmonic content riding on the fundamental.

Voltage transients are short spikes from switching or faults, not the steady distortion caused by continuous harmonic currents. Mitigation is a corrective action, not a phenomenon. Apparent power is the combination of real and reactive power and doesn’t specifically describe waveform distortion.