Basics of DC Circuits: Electrical Circuit or Electrical Network

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The interconnection of various active and passive components in a prescribed manner to form a closed path is called an electric circuit.

Basics of DC Circuits: Basic Properties of Electric Circuits

A circuit is always a closed path.

A circuit always contains at least an energy source which acts as a source of electrons.

The electric elements include an uncontrolled and controlled source of energy, resistors, capacitors, inductors, etc.

In an electric circuit flow of electrons takes place from negative terminal to the positive terminal.

The direction of flow of conventional current is from positive to negative terminal.

The flow of current leads to a potential drop across the various elements.

Basics of DC Circuits: Types of Circuits

Open Circuit

If due to disconnection of any part of an electric circuit if there is no flow of current through the circuit, is said to be an open circuited.

Short Circuit

A short circuit is simply a low resistance connection between the two conductors supplying electrical power to any circuit.

Node

A point or junction where two or more circuit’s elements (resistor, capacitor, inductor etc.) meet is called Node. In other words, a point of connection between two or more branches is known as a Node.

Branch

That part or section of a circuit which locate between two junctions is called the branch. In a branch, one or more elements can be connected, and they have two terminals.

Loop

A closed path in a circuit where more than two meshes can occur is known as Loop i.e. there may be many meshes in a loop, but a mesh does not contain on one loop.

Mesh

A closed loop which contains no other loop within it or a path which does not contain on other paths is called Mesh.

Basics of DC Circuits: Types of Components

Active Component

An active component is an electronic component which supplies energy to a circuit. Active elements have the ability to electrically control electron flow.

Example: Voltage sources, Current sources, Generators (such as alternators and DC generators), All different types of transistors (such as bipolar junction transistors, MOSFETS, FETs, and JFET), Diodes (such as Zener diodes, photodiodes, Schottky diodes, and LEDs)

Passive Components

A passive component is an electronic component which can only receive energy, which it can either dissipate, absorb or store it in an electric field or a magnetic field.

Example: Resistors, Inductors, Capacitors, Transformers.

Basics of DC Circuits: Types of Voltage Sources

Ideal Voltage SourceIdeal voltage source is a voltage source having no internal resistance. This means there is no voltage drop inside the source, so one gets the same voltage level at the terminals of the source as produced inside the source.

Practical Voltage Source

Sources having some amount of internal resistances are known as Practical Voltage Source. Due to this internal resistance; voltage drop takes place, and it causes the terminal voltage to reduce.

Basics of DC Circuits: Types of Current Sources

Ideal Current Source

The internal resistance of an ideal current source is infinite. An independent current source with zero current is identical to an ideal open circuit.

Practical Current Source

Practical Current Source has some internal resistance connected in parallel to Ideal Current Source. And some of the current flow through it and the amount of flow depends upon the load.

Basics of DC Circuits: Types of Networks

Linear Network

A network in which the parameters of resistance, inductance, and capacitance are constant with respect to current or voltage, and in which the voltage or current of sources is independent of or directly proportional to other voltages.

Non-Linear Network

A nonlinear circuit is an electric circuit whose parameters are varied with respect to Current and Voltage. In other words, an electric circuit in which circuit parameters (Resistance, inductance, capacitance, waveform, frequency etc.) is not constant, is called Non-Linear Circuit.

Bilateral Network

A network or circuit in which the magnitude of the current remains the same when the voltage polarity is reversed is called a bilateral network. For example, a transmission line is bilateral since it can be made to perform its function equally well in either direction.

Unilateral Network

A circuit whose operation, the behaviour is dependent on the direction of the current through various elements is called unilateral network. Circuit consisting diodes, which allows the flow of current only in one direction is a good example of a unilateral circuit.

Basics of DC Circuits: Types of Connections

Series Connection

In a series circuit, all components are connected end-to-end, forming a single path for current flow

Voltage drops add to equal total voltage.

All components share the same (equal) current.

Resistances add to equal total resistance.