Circuit diagrams
1. Series connections
Components that are connected one after another on the same loop of the circuit are connected in series.
Two lamps connected in series
The circuit diagram shows a circuit with two lamps connected in series.
If one lamp breaks, the other lamp will not light.
Series circuits are useful if you want a warning that one of the components in the circuit has failed.
If Christmas tree lights are connected in series they all go out when one bulb breaks.
2. Parallel connections
Components that are connected on separate loops are connected in parallel.
The current is shared between each of the circuit loops.
Two lamps connected in parallel
The circuit diagram shows a circuit with two lamps connected in parallel.
If one lamp breaks, the other lamp will still light.
The lights in most houses are connected in parallel.
This means that if one bulb breaks the others remain on.
For a parallel circuit, the sum of all the current in every branch is equal to the current from the cell.
