1. Introduction: The Wires That Run Your Home
Look up at the wall where the electricity meter sits in your house. Two thick wires come in from the pole on the street and disappear into that meter. From there, thinner wires branch off and run behind the walls to every bulb, fan, plug point and the geyser in the bathroom. That whole hidden web is your domestic electric circuit — the wiring system that carries power from the street to each switch in your home.
Most people flip a switch and never think about it. But there is a careful piece of physics behind those wires: how they are arranged, why one of them is there only for safety, and why a thin little wire inside the fuse box is the thing that stops your house from catching fire.
Stop scrolling. Try it in your head before reading on. When you switch on the geyser and the tube-light at the same time, why does the tube-light not go dim?
By the end you will be able to name the three wires that enter a home, say why every appliance is joined in parallel, and work out what size of fuse a given appliance needs. Let us treat the home wiring itself as the "device" and see what it is secretly doing.