top of page

Introduction to Circuits

Updated: Aug 26, 2020

'Circuit' is a word that any person involved in #technology gets to hear in almost every conversation. Starting right from lighting a simple bulb to managing the entire city's #electricity is a circuit, which shows how inevitable it is in our day-to-day lives.

A circuit is a closed path which lets electricity pass through it.

But, before jumping directly onto its details, let us analyze the important element of any circuit, VOLTAGE.


You might have heard your parents saying that there isn't enough 'voltage' during the time of power cut or reduced power. In simple words, voltage is a measure of the electric potential created by a battery.

For any circuit to work, there should be a supply for electricity. Voltage is that element which makes electricity move; i.e. from higher voltage to lower #voltage. The aim of a circuit is to make a conductive path for electricity to travel through it.

But, the question has to be asked, what is this high/low voltage and where can we find it?

Electricity is always generated from a source that has two terminals, a positive and negative one. This way, the circuit provides a path for current to flow where the positive terminal is the point of higher voltage and negative being of lower potential.

Basic circuit diagram

Now we know that electricity passes through a circuit when there is a difference in voltages. But how do we humans know that current is actually passing through the circuit? After all, we cannot see the electrons running from one corner to the other with our naked eye.

Hence, we connect a small #LED or light to test whether it is working or not. If the LED glows, it is proof that the circuit is complete.

Open Circuit and Short Circuit

Open Circuit: Open circuit is the condition where there is no current passing through the conducting material. You cannot really call this a circuit because it is not fully wired and hence is not complete. An open circuit never causes any harm to the components but will always be difficult to spot especially if you are a beginner.

Protip : If you have a multimeter available, then it will play an instrumental role in helping you detect an open circuit where you can just check the potential between two points and know about it.

Short Circuit: Warning! You definitely don't want this! If you make a connection, directly from the positive to the negative #terminal, it is known as a short circuit. Remember when it was mentioned that this can be used to light up an LED or so? Circuits are meant to be useful and if there is no restriction in between, it will let the current travel in loop infinitely.

In circuits that consume a huge amount of power, a short circuit could cause major damage to the equipment, wiring, and even the #power supply. This is the real reason why each house has a fuse or any kind of circuit breaker; to prevent every equipment in the house to be protected from short circuitry.

There is a similar issue where there is current passing through a certain area extensively. Though this isn't a short circuit exactly, it is somewhat closely related. In order to prevent this, the #resistance values can be made right and ensure that too much current doesn't flow through a particular instrument.

From this, it can be understood that a circuit is the most basic element in electronics and is a vast topic that cannot be finished in an article. But do stay tuned, to learn more.


See Also:

45 views2 comments

Related Posts

See All


Anushka Gupta
Anushka Gupta
Aug 01, 2023

What a gem of a blog! The explanations are clear, and the examples are easy to follow. Learn Electronics India has truly made learning about circuits enjoyable and accessible.


Short and effective! LearnElectronics India never disappoints.

bottom of page