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# Electric Circuit: Types of circuits with Diagrams and PDF

In this article, you’ll learn what is an electric circuit and it’s different types of circuits with diagrams.

## Electric Circuits and Types

Contents

The Electric circuit is a path through which electric current flows. The figure represents a simple electric circuit.

Depending upon the type of current flowing, the electric circuit is classified into D.C. circuit and A.C. circuit.

## Types of Electrical Circuits with Diagram

Following are the types of electrical circuits with Diagram:

1. D.C. Circuit
2. A.C. Circuit
3. Closed-circuit
4. Open circuit
5. Short circuit
6. Series Circuit
7. Parallel Circuit
8. Series-Parallel Circuits

### 1. D.C. Circuit

The circuit in which direct current (D.C.) flows is known as D.C. circuit.

The figure represents the D.C. circuit. Direct current (D.C.) is a unidirectional current whose magnitude remains constant. D.C. can be represented as shown below.

### 2. A.C. Circuit

The circuit in which alternating current flows is known as A.C. circuit. The simple A.C. circuit is shown in the figure.

Alternating current is a bidirectional current, whose magnitude and direction changes periodically at regular intervals of time. The A.C. can be represented as shown below.

### 3. Closed-Circuit

Depending upon the condition of the circuit A.C. or D.C. circuits are classified into three circuits they are:

• Closed-circuit
• Open circuit
• Short circuit

In the closed-circuit the current path is closed i.e. current starts from the positive terminal of the supply, through the line, load, neutral and ends in the negative terminal of the supply. The closed-circuit is shown in the figure.

### 4. Open Circuit

In open circuit current won’t enter back to the negative terminal of the supply i.e. current path is incomplete due to the break in the circuit. The open circuit is shown in the figure.

### 5. Short Circuit

The circuit in which line and neutral wires are shorted (touch each other) is known as a short circuit. Here current returns back directly to the negative terminal of the supply, without passing through the load as shown in the figure

### 6. Series Combination of Resistances:

When the resistances are connected end-to-end as shown in the figure they are said to be connected in series.

In the above figure resistance R1, R2, & R3 are connected in series, across supply voltage of ‘V’ volts. in series circuit current through each resistance is same, the voltage drop across each resistance is different and the sum of voltage drops is equal to the voltage applied.

Since the voltage applied is equal to the sum of voltage drops across three resistances, the relation between V, V1, V2, V3 is given by,

If R is the total resistance of the combination and I is the total current through the combination, then total voltage V=IR.

The above equation represents that the total or effective resistance of a series circuit is equal to the sum of all individual resistances connected in series.

#### Characteristics of a Series Combination of Resistances

• The equal current flows in all parts of the circuit.
• Individual resistors have their individual voltage drops.
• The applied voltage is equal to the sum of individual voltage drops.

### 7. Parallel Combination of Resistances:

In a parallel combination of resistances, all the starting ends of resistances are connected to one common point and all finishing ends are connected to another common point as shown in the figure.

Consider the above figure in which R1, R2, R3, are connected between common points A & B across supply voltage of V volts. In parallel combination, the potential difference across all resistances is the same (i.e. V volts), current in each resistor is different and is given by ohm’s law and the total current (I) through the combination is the sum of individual currents through individual resistances.

If R is total resistance of the combination, the total current I= V/R ∴ above expression becomes,

The above equation represents that the reciprocal of the total resistance of the circuit is equal to the sum of reciprocals of individual resistances connected in parallel.

#### Characteristics of a parallel combination of resistances

The main characteristics of a parallel circuit are:

• The voltage drop across each resistor is the same as the applied voltage.
• Individual resistors have their individual current.
• The total current is similar to the sum of the individual currents.

### 8. Series-Parallel Combination of Resistances:

In this combination resistances are connected in series as well as parallel as shown in the figure.

To reduce such combinations to simpler form the following steps are adopted :

• Find the effective resistance of the parallel combination of resistances.
• Replace the parallel combination to its equivalent resistance. Now-R1 is in series with the effective resistance of parallel combination.
• Determine the total resistance of the whole circuit.

If the circuit contains a series and parallel combination as shown in the figure then the following steps are adopted :

• Find the effective resistance of the series combination of R2, R3, and R4.
• Replace the series combined with its equivalent resistance.
• Calculate the effective resistance of the whole circuit (i.e. parallel combination between R1, and effective resistance of R2, R3, & R4). 