What Happens When You Use a Coiled Extension Cord? – The Hidden Electromagnetic Science of Power Reels

We've all used extension cords, especially on campsites, construction sites, or in storage areas. They're incredibly useful for powering tools or appliances over a distance. But have you ever heard that using a cord without fully uncoiling it can be dangerous? Most people assume it just gets hot, but the reality is much more fascinating—and dangerous. There's real electromagnetic science at play when you use a coiled power reel. Understanding how a coiled cord behaves like an inductor will change the way you use electricity.     The Science Behind Coiled Cords Acting Like Inductors When current flows through a coiled extension cord, the spiral shape of the cable causes magnetic fields to form and interact. This turns the cord into a passive inductor , just like a coil in an electrical circuit. Inductors resist sudden changes in current. This resistance can lead to voltage spikes , electromagnetic interference (EMI) , and power instability . A coiled c...