Copper wire is used in homes because it carries electricity with very little resistance.

The longer version

Electricity moves through a metal as electrons drift past the atoms. Copper offers them a particularly easy route, since its atoms scatter the drifting electrons very little, so little energy is lost as heat along the way. Silver is slightly better, but far more expensive for the same job.

Low resistance matters because any loss turns into warmth inside the walls. A material with high resistance would heat the cable dangerously and waste power. Copper is also flexible and resists corrosion, which helps joints stay reliable over decades, and those combined properties explain its widespread use in building wiring.

Where this entry sits

Everyday physics and chemistry hide small wonders in plain sight, from kitchen reactions to the light in the sky. These short facts explain matter, energy, electricity, magnets, sound, and the simple units we use to measure the world. The full list sits on the Science and Physics page, where every entry is listed in order.