Harmonics on single-phase powerlines are generally caused by a device such as a _____.

A) ​triac light dimmer
B) lamp with an incandescent bulb
C) single-speed motor
D) ​heater

Single-Phase Powerlines

Electrical power supply lines that deliver alternating current with a single waveform, commonly used in homes and small businesses.

Triac Light Dimmer

A type of switch used to control the brightness of a light, by altering the timing of a triac to regulate the amount of power reaching the light.