AN ELECTRIC CIRCUIT
Without trying to make an electrician out of anyone, let’s take a quick run through the basics of an electrical circuit. Unless you know this, such concepts as an electrical ground and short circuit will be very foreign to you,and you may miss something obvious when troubleshooting an electrical problem.
The word circuit comes from circle, and what it means in practical terms is that there must be connections from the source of current to the users of the current, then back to the source. Electricity travels in only one direction, so the wire that goes to the source cannot be used as the return.
The simplest circuit is shown in l-10. Current leaves a terminal on the battery and goes through the wire to the light bulb, a device that restricts the current flow SO sharply that the wire inside the bulb becomes hot and glows. When the current passes through the restrictive wire (called a filament in the light bull)), it continues through a second segment of wire back to a second terminal on the battery.
If any part of the circuit is broken, the current flow stops and the bulb will not light. Normally the filament burns out eventually, but the bulb also would not light if either the first or second segment of the wiring between bulb and battery broke. Note that even if the wire from battery to bulb were intact, the bulb would not work if the return wire broke. A break any place in a circuit is called an open circuit; such breaks usually occur in the wiring. Wires normally are covered with insulating material to hold in the electricity, so if the metal strands inside (called the conductor) were to break, you might not see the problem by merely looking at the wire.
Post time: Jul-20-2023