# The advantages of a parallel circuit

Parallel circuits are often not given the value they have. People who are not old enough to remember how a whole series of Christmas lights went off because one of the light bulbs had melted, which was still the challenge of finding out what the light bulb was, may not be aware of the advantages of a parallel circuit.

## Practical application

A circuit is a closed path for electricity to flow from its source, through a charge such as a light bulb or any electrical device, and back to the source. Any interruption in the path, either deliberate (a switch in the off position) or unintentional (a blown bulb, a broken wire, or a power supply failure) “opens” the circuit and stops it from working.

There are two types of electrical circuits: series circuits and parallel circuits. Serial circuits, such as the light strip mentioned above, have a single path for electricity to flow. Any interruption in the path causes the entire circuit to stop working: the entire strip of lights goes out due to a single damaged bulb. Parallel circuits have multiple paths through which electricity can pass, so that a single broken bulb would not cause the entire circuit to stop working.

Electromotive force (E) or voltage (V): The equivalent of the pressure in a water pipe.

Current (I): The speed of the flow of electricity between two determined points.

Resistance (R): Opposition to the flow of electricity.

Ohm’s Law: The formula used to calculate the previous values. If you know any pair of them, you can find out the third one.

The differences in circuit design become clearer when Ohm’s Law is applied. Let’s see a simple example: two resistors, ten ohms each, connected in series offer a resistance of twenty ohms. The values ??simply add up to provide the total resistance of the circuit.

The same two resistors connected in parallel offer a total circuit resistance of five ohms. (The resistance is calculated by adding the inverses (1 / x) of the resistors, and then doing the inverse of that number). The resistance in a parallel circuit decreases. That means it costs less to supply power to the resistors in parallel than it would cost to supply the resistors in series.

The previous example may not seem like much, when talking about two small resistances to which a battery supplies them energy. If we extend it to the size of your car, the advantages become clearer. Imagine the energy that would be needed if the lights, the radio, the air conditioning, the windshield wipers and everything else that a modern car carries were connected in series. Imagine the bills that would come to you from the mechanic if you had to find out why nothing would work every time a single thing in the car failed. This shows the advantages of the electric circuit in parallel.