Circuit Diagram And Its Components

Before talking about a circuit diagram, let us recall circuits. An electrical circuit is a device which provides the complete path for current to flow. A circuit consists of three basic things to function:

  • a source of voltage
  • a conductive path which facilitates the movement of charges
  • a resistor (say, a light bulb) which requires electricity to do work

Apart from the basic requirements, a circuit consists of a number of components which provide different functionalities. In this article, we will discuss an electrical circuit and its components with a circuit diagram.

What is a Circuit Diagram?

A circuit diagram is a simplified representation of the components of an electrical circuit using either the images of the distinct parts or standard symbols. It shows the relative positions of all the elements and their connections to one another. It is often used to provide a visual representation of the circuit to an electrician. The following figure shows a simple circuit diagram.

Circuit Diagram

Components of Circuit Diagram

Let us learn about some of the important components of circuits and their symbols in a circuit diagram.

  • An electric cell: It provides the source of current. In its symbol, the larger terminal is positive, whereas the smaller one is the negative terminal.

Circuit Diagram

  • A battery: It is a combination of cells and its utility is the same as cell.

Circuit Diagram

  • Switch: It is a plug key used to allow or stop the flow of current upon being pressed. It may be an open or a closed switch.

Circuit Diagram

  • Wire joint: One device may be connected to the other using wires. This is shown by drawing ‘blobs’ at their point of connectivity.

Circuit Diagram

  • Wires crossing without joining: The wires that do not touch each other are drawn without blobs. The following figure shows how the unjoined wires are represented.

Circuit Diagram

  • Electric bulb: The electrical device which uses electricity to glow.

Circuit Diagram

  • Resistor (R): It is used to restrict the amount of current flow in the circuit.

Circuit Diagram

  • Variable resistance: Also known as the rheostat, it is used to regulate the amount of current flow by increasing or decreasing the resistance to the current flow.

Circuit Diagram

  • Ammeter: It is used to measure the current passing at a particular point.

Circuit Diagram

  • Voltmeter: It is used to measure the voltage between two points in a circuit.

Circuit Diagram

 


Practise This Question

For how long time period should a flow of 1019 electrons be maintained between two points A and B to have a constant current of 8 A between them?