Why Do Power Lines Hum and Glow?

Video Description

Electricity travels thousands of kilometres before it reaches our homes, but how do transmission lines make this possible? In this video, we explore the complete journey of power — from 765 kV at generating stations down to 230 volts at our household supply We explain how aluminium conductor steel reinforced (ACSR) lines carry such high voltages, and why many thin strands are used instead of a single thick wire. You will learn about the skin effect, sag, and the role of Stockbridge dampers in controlling vibration The video also covers the mystery behind the humming sound and faint glow near high-voltage lines, the science of corona loss, and how corona rings and bundle conductors reduce power loss We then explore how transmission lines act like capacitors, causing capacitive interference, and how substations use shunt reactors and shunt capacitors to maintain stability Finally, you will see how to identify line voltages by counting insulator discs, and the purpose of red or yellow balls placed on lines near airports