Voltage in Parallel Circuits (Sources, Formula & How To Add)

Contents

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Key learnings:

Voltage in Parallel Circuits Definition: A parallel circuit is defined as one where multiple devices are connected side by side, each in its own branch, with the same voltage across each branch.
Current Distribution: The total current in a parallel circuit is the sum of the currents through each branch, allowing multiple paths for current flow.
Resistance Calculation: In parallel circuits, adding more branches decreases the overall resistance, making it easier for the current to flow.
How to Add Voltage in Parallel: The voltage across each device in a parallel circuit is equal to the source voltage, ensuring consistent voltage across all branches.
Advantages and Applications: Parallel circuits are used in homes and various applications because they allow independent operation, full voltage to each device, and isolate faults effectively.

What are Voltages in Parallel?

A parallel circuit or parallel connection refers to when two or more electrical devices are linked together in a side by side like arrangement within a circuit. In this connection, every device is located in its own distinct branch. Voltage (i.e. a potential difference) is the reason that current passes through a closed circuit. This article will discuss in detail voltages in a parallel circuit.

In a parallel circuit, multiple branch lines create several pathways for the charge to travel. When the charge reaches a node, it chooses a branch to pass through to return to the low potential terminal.

Consider a closed circuit with a voltage source and a resistor. The current flows through this single pathway. Now, add two more resistors in parallel with the first one.

It results in multiple pathways for the current to pass through rather than a single pathway to reach the low potential terminal. So, with the increase in the number of branches, the overall resistance decreases and it is obvious that the current in the circuit increases.

That is, the entire current will be the sum total of the different currents through the three resistors. Here in the parallel circuit, we can see that there are at most two sets of electrically common points. That is; A and H, B and G, C and F, D, and E in the circuit shown below. Voltage, which is measured across the common points for all time, should be equal.

The first figure shows a closed circuit with a voltage source and one resistor. The second figure shows a parallel circuit with three resistors and a voltage source.

The voltage in this circuit is the same for each and every three branches and it is also the same as the voltage of the source. Formulalicaly, that is:

The total current in this given parallel circuit is represented by I_total. The formula for this is given as.

The total or effective resistance of this given parallel circuit is described in the formula below.

Thus, we can conclude that by adding additional branches in a particular parallel circuit, the total current will get increased and the circuit gets overloaded.

Advantages of Parallel Circuits

When we want to connect two bulbs to a single battery, there are two options for us. Either it can be connected in an array or in parallel. If we connect it in an array, the two bulbs will be in the single and same conducting path between the two terminals of the battery. The problems with this connection are the following

We cannot turn on or operate one bulb.
Both the bulbs will be dim since they are using the same source.
If there is a fault in one bulb, then the whole circuit will be affected.

When we connect the two bulbs side by side in parallel, each bulb receives the full voltage from the battery. This setup has several advantages.

Both bulbs get the full amount of voltage in the battery.
We can operate two bulbs separately.
Both the bulbs will be bright when turned on.
If there is a fault in one bulb, it can be removed or repaired. Thus, the whole circuit will not be affected.

Parallel Circuits in Home

All our appliances at home are connected in parallel with each other. That is why we can operate every appliance separately without affecting others. For example, we can turn on the washing machine without turning on microwaves or television as well.

We know that in our house, the electrical cables comprises three wires- live, neutral and earth. For this moment we are ignoring the earth and simply concentrate on a live wire and a neutral wire.

The voltage is present across the live and neutral wire which is connected ultimately to a power plant. Each and every socket in our house is linked to these live and neutral. When we plug in a metal pin of an appliance into this socket, it creates an electrical connection with this socket.

Every appliance possesses its own connection among the live and neutral wire. So, when we switch on the device, the whole voltage will be present across it and it can be operated separately.