SERIES CIRCUITS - the basic anatomy

 

THE BASICS OF SERIES CIRCUITS

A circuit is a path for electrons to flow through. The path is from the positive terminal of a power source, through the various components and on to the negative terminal (Conventional Theory) or, if you prefer from the negative terminal to the positive terminal of the power source (Electron Theory) . Think of the circuit as a circle. The paths may split off here and there, but they always form a line from positive to negative.
 
If you look at the diagram below, you will see the basic structure of a simple circuit.
If we break a circuit down to its basic blocks, we get:
 
1.    A Power Source: battery
2.    A Path along which the electricity will travel: wire.
3.    A Load: lamp

4.    A Control: switch

 

Series Circuits

A series circuit is one with all the loads in a row. There is only ONE path for the electricity to flow. So, as you can see this is a circuit where there is only one path from the source through all of the loads and back to the source. The filament (the wire in each bulb that looks like a little coil) in each bulb in the string of lights shown in diagram #1 is a part of the path that the electricity must flow through to complete the circuit. If this circuit was a string of light bulbs, and one blew out, the remaining bulbs would turn off as shown in diagram #2

Diagram #1- unbroken circuit path electricity flows and bulbs light up.

Diagram #2 – filament burnt out creating a gap in the circuit path, electricity cannot flow, circuit does not light up.

The most familiar example of a series circuit is a string of classic Christmas tree lights, in which the loss of one bulb shuts off the flow of electricity to each bulb further down the line as illustrated in the diagram above. In a series combination, if a single light bulb burns out then the other bulbs will also not work. This implies that a fault in one light bulb will result in the entire series circuit not working. The same applies if the wire is cut along the electric path as shown in diagram #3 below.

Diagram #3