# Circuits

Are you curious about how electricity works? Well, an electric circuit is a group of electronic parts that are joined together. These parts include sources, ground, resistors, and other devices. When you turn on a circuit, electrons travel through a wire that makes a closed loop. This loop is called an electrical network. So, in simple terms, a circuit is like a path that electricity flows through. And the cool thing is, you can make your own circuits at home with some basic supplies! Just remember to be safe and never touch wires with wet hands. If you want to learn more about circuits, keep reading and explore the amazing world of electronics.

## What are the basic components of a circuit?

Have you ever wondered how electronic devices work? Well, they all have something in common: circuits! A circuit is made up of different parts, including resistors, transistors, inductors, diodes, switches, capacitors, ground, and other sources. These parts are connected by wires or traces to create a path for electricity to flow through.

Two of the most important circuit components are resistors and sources. Resistors help to control the flow of electricity in a circuit, while sources provide the power needed to make the circuit work. By understanding how resistors and sources work, you can start to get a better understanding of how circuits function.

**Resistors in circuits**

Have you ever looked inside an electronic device and wondered what all those little components do? Well, one of the most important parts is the resistor. A resistor is a small electronic component with two terminals that can control the flow of electricity in a circuit.

Resistors are used in electronic circuits for a variety of purposes. One common use is to reduce the flow of current in a circuit. This can help protect other components from being damaged by too much electricity. Resistors can also be used to adjust signal levels, divide voltages, bias active components, and terminate transmission lines.

Here is Ohm’s law for calculating the resistance:

V stands for voltage in volts, I is for current in amperes, and R is for resistance in ohms. The variable resistor is another component that allows us to control how much current flows across a circuit. It operates by moving a wiper terminal over a resistive substance, which is usually a thin film, a chunk of carbon, or a resistive wire composed of nickel-chromium or tungsten alloys.

**Sources in circuits**

Electric circuits rely on sources to provide the power needed to make them work. There are three main types of sources used in electric circuits: current sources, AC voltage sources, and DC voltage sources.

A current source is an electronic component that either provides or absorbs electricity. There are two types of current sources: independent and dependent. An independent current source delivers a continuous current, while a dependent current source generates current proportional to another voltage or current in the circuit.

An AC voltage source is a device that supplies alternating power and frequency to a load. The graph of an AC power source has the shape of a sine wave, with the amplitude representing the maximum voltage in volts, and the frequency measured by period per second.

A DC voltage source, on the other hand, is a device that supplies constant voltages and currents to the circuit. This is important for devices that require a steady flow of power, such as computers or cell phones.

By understanding the different types of sources used in electric circuits, you can start to get a better understanding of how these devices work.

While the values you see next to the current source and the DC voltage source are constant, the value you see next to the AC power source is the value of the sine wave’s amplitude.

## What are the types of circuits?

When it comes to electric circuits, there are five main types that you should know about: closed circuit, open circuit, short circuit, series circuit, and parallel circuit.

An open circuit is a circuit that has no current flowing through it. This happens when the circuit's continuity is interrupted, and the current does not flow as a result. An open circuit is any circuit that does not pass current when a potential difference is created, and its resistance is infinite.

In contrast, a closed circuit is a complete electrical connection around which current flows or circulates. A closed circuit is formed when a succession of electrical wires connect to each other and complete a circuit, allowing electricity to flow from one end of the circuit to the other.

Two other important types of circuits are series circuits and parallel circuits. In a series circuit, components are connected end-to-end, forming a single path for current flow. This means that if one component fails, the entire circuit will fail. In a parallel circuit, components are connected across each other, forming multiple paths for current flow. This means that if one component fails, the other components will continue to function.

**Series circuit**

A series circuit is a circuit in which the entire current passes through all components without dividing.

The same amount of current goes through all the components without dividing in a series circuit. To calculate the total voltage in a series circuit, we use this equation:

V is the voltage value of the DC voltage source. VR1, VR2, and VR3 are the voltage values of the resistors.

Here is the equation for calculating the total resistance:

RTotal is the total value of resistance in ohms. R1, R2, and R3 are the resistance values in ohms.

The total current in series circuits is the same value as the individual current for all components. You can define it as:

I1, I2, and I3 are the values of the current going through R1, R2, and R3 in amperes.

**Parallel circuit**

A parallel circuit has branches that divide the current so that just a portion of it travels through each branch. In a parallel circuit, the voltage (or potential difference) between each branch is the same, but the currents may vary.

In order to understand and design electric circuits, it's important to know how to calculate the total voltage, resistance, and current in a parallel circuit.

First, let's look at the total voltage in a parallel circuit. The total voltage is the same value as the individual voltage for all branches. We can define it as:

V = V1 = V2 = V3

Where V is the voltage of the DC voltage source, and V1, V2, and V3 the voltage values of the resistors on the different branches.

Next, let's look at the total resistance in a parallel circuit. We can use the following equation to calculate it:

1/RTotal = 1/R1 + 1/R2 + 1/R3

Where RTotal is the total value of resistance in ohms, and R1, R2, and R3 are the resistance values of the resistors in ohms.

Finally, let's look at the total current in a parallel circuit. We can use the following equation to calculate it:

ITotal = I1 + I2 + I3

Where I1, I2, and I3 are the values of the current going through R1, R2, and R3 in amperes.

If you want to calculate the current through an individual resistor in a parallel circuit, there is a shortcut. Let's say we want to calculate the current through R1 in the diagram above. First, we can find the total resistance of R2 and R3 using the equation:

1/Rp = 1/R2 + 1/R3

Then, we can use the following equation to find the current through R1:

I1 = ITotal * (Rp / R1 + Rp)

This is also known as a current divider.

Circuits - key takeaways An electrical circuit is a collection of interconnected electronic components. The basic components of an electric circuit are sources, ground, resistors, inductors, diodes, capacitors, switches, and transistors. The five main types of electric circuits are closed circuits, open circuits, short circuits, series circuits, and parallel circuits. An open circuit is a circuit that has no current flowing through it because of an interruption. A closed circuit is a complete electrical connection around which current flows or circulates. The main difference between a series and parallel circuit is that whilst the current is not divided in the series circuit, it is divided into branches in a parallel circuit.

## Circuits

**What is a circuit breaker?**

A circuit breaker is a safety device that protects an electric circuit when there is too much current or a short circuit.

**What is a series circuit?**

A series circuit is a circuit in which the entire current passes through all of the components without dividing.

**What is a parallel circuit?**

A parallel circuit is a circuit that has branches that divide the current so that just a portion of it travels through each branch.

**What is a circuit?**

An electric circuit is a collection of interconnected electronic components.

**What is a short circuit?**

A short circuit is an improper connection between two nodes of an electric circuit with voltages that are supposed to be different but aren’t.