# CBSE Class 6 Science Revision Notes Chapter 12

## CBSE Class 6 Science Chapter 12  Revision Notes – Electricity and Circuits

Electricity in Science is defined as the flow of electrons through a circuit. It is crucial to understanding the concept of electrical conduction through a circuit. Chapter 12 of CBSE Class 6 Science explains these concepts in detail. The electrical components required for a circuit are also described. It lists the different types of electrical conductors and insulators. The chapter goes on to explain the additional effects of electricity, including the effects of heating, lighting, and magnetism.

Extramarks’ Revision Notes for CBSE Class 6 Science Chapter 12 are written in an easy-to-understand language for students to revise quickly and effectively before their examinations. Students can access these notes from the website at their convenience.

## Revision Notes for CBSE Class 6 Science Chapter 12

### Access Class 6 Science Chapter 12 – Electricity and Circuits Notes

Definition of Electricity

Electricity is the movement of charges (electrons) or electrical power through a suitable medium. For example, the wires used in homes. Electric currents can be produced by batteries, generators, inverters, dry or electric cells, or by converting other energy sources.

Electric Circuit:

A closed path known as an electric circuit delivers a constant flow of electrons or electric current from a source of voltage to the machinery in use. The term “current flow” refers to the movement of electricity in a circuit from one terminal of a power source, such as a cell, to another. The starting terminal is typically regarded as positive and the ending terminal as negative. A simple circuit consists of two wires connecting a bulb to a battery. As long as the battery is not dead and the bulb is not fused, it will begin to glow.

A circuit diagram is a representation of this current flow path or circuit using various symbols and notation for various components.

Open and Closed Circuits

When the path taken by an electrical current from one termin

al to its opposite terminal is uninterrupted and continuous, it is referred to as a closed circuit. However, if the same path is broken somewhere along the way, it is referred to as an open circuit.

Electrical Components

1. Wire: Wires are electrical conductors that connect two or more electrical components and allow current to flow.The wires are typically made of metals that are effective electrical conductors. The type of metal and wire size are chosen based on the application.
2. Bulb: It is a filament inside a glass case that is connected to two terminals and heats up when an electric current flows through it and emits light. Typically, tungsten wire coils are used to create the filament wire. The two terminals between which the filament is located receive the electricity.
3. Electric Cell or Dry Cell: It is a particular type of apparatus that captures chemical energy and transforms it into electrical energy that can be applied to various tasks. Positive and negative terminals make up its two terminals. Charges move from the negative to the positive terminal inside a cell, whereas the opposite occurs outside the cell.
4. Battery: A battery is a collection of two or more cells connected in series.
5. Switch: An electrical circuit uses this device to allow or restrict the steady flow of current. When activated, it creates a conducting medium between two gaps in a circuit, allowing the circuit to function.. When turned off, it breaks the circuit by removing the conducting medium from its gap.

An electric torch is made up of a battery, an LED (Light Emitting Diode) bulb, and the above-mentioned parts altogether.

Electrical Conductors and Insulators

The materials that permit the flow of electricity through them are known as electrical conductors. All metals fall into the category of excellent electrical conductors. The only non-metal that conducts electricity is carbon, which can be tested by laying wires across a pencil’s two ends.

On the other hand, materials that do not permit the flow of electric currents are referred to as insulators or poor conductors. Some examples of insulators include plastic, rubber, dry wood, PVC, etc.

Effects of Electricity

The passage of an electric current through a material is accompanied by a number of additional effects, some of which can be put to other uses or result in energy losses. Some of these effects are discussed below.

• Heating Effect: When an electric current passes through a conductor, heat is generated due to the conductor’s resistance to the flowing current. Electric heaters, ovens, and other devices use this effect to generate heat.
• Lighting Effect: When an electric current passes through the filament of an electric bulb,  the thin wire glows as a result of the current flow.
• Magnetic Effect: When an electric current is passed through the coil, the metal becomes magnetic. Electromagnets make use of the magnetic effect. An electromagnet is a magnet made up of a piece of iron or steel surrounded by a coil.
• Chemical Effect: A solution ionises and breaks down into ions when an electric current flows through it. This chemical action is used in electroplating and electrolysis.

### 1. What is an electric circuit?

Electricity is defined as the flow of electrons or charges through a suitable medium of conduction, typically the wires that come from batteries, cells, or generators. A closed path of conduction known as an electric circuit enables a constant flow of electrons from one end of the current source to the other terminal end of the apparatus being used.

### 2. What are the various components of the electric circuit?

The following elements are necessary for an electric circuit to function properly so that electrons or charges can flow continuously through the medium of conduction. A cell, a device that transforms chemical energy into electrical energy, or a battery, which is a combination of cells, is one of the components. A switch is used to open or close the function of the circuit. Other components include wires used for conduction.

### 3. What are electric conductors and insulators?

To generate electricity, charge moves from one terminal end of the current source to the other.Conductors are the components in a circuit that permit the flow of current through them. All metals, carbon, and nonmetals, are recognised as being good electrical conductors because electrons pass through them with ease. Insulators, or poor electrical conductors, are objects that do not allow electrons to pass through them. For example, rubber.

### 4. What are the effects of electricity?

The passage of electric charges through a medium is usually accompanied by some effects. These effects are caused by electricity and are used for other purposes that help in the completion of various tasks. The different effects of electricity include the heating effect, which is used in electric heaters for iron, the lighting effect, which is used in light bulbs and other similar objects, and the magnetic effect, which is used in the field of electromagnetics.