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Electricity Year 3 & 4

Electricity
Year 3 & 4

Electricity Year 3 & 4 kids at Primary School KS2. Science homework help. Learn about electrical circuits, open and closed circuits, conductor and insulators.

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What is a circuit?

A circuit is a path that electricity travels around. Electricity needs a complete loop to work properly. This means the electricity must be able to travel all the way around the circuit and back to where it started.

If there is a gap or break anywhere in the circuit, the electricity cannot flow. When this happens, the device will not work. For example, a bulb will not light or a buzzer will not sound.

Blobz game playBlobz: Electric Circuits
Learn about circuits then play the game and take the quiz to test what you know.
A electric circuitPower up: Circuit Builder
Drag the components to where you want the in the circuit. Choose a battery and explore.
Bitesize - CircuitsBBC Bitesize - Circuits
What circuits are and electrical symbols in circuits

Electricity flows around in a loop

Electricity flows from a cell (battery), through wires, and back to the cell again. As it moves around the loop, it passes through components such as bulbs, buzzers or motors and makes them work.

When the loop is complete, electricity can flow easily and the circuit works. When the loop is broken, electricity stops flowing and the circuit stops working.

A complete circuit is made up of different components. Batteries (or cell), wires and bulbs, buzzers and motors are all components.

If a wire is broken the circuit will be broken and it won't move the electricity around it.

Bulb circuit

  • Build a simple circuit with a battery, wires and a bulb. If you don't have a circuit kit of your own use this website.
  • Make the bulb light up.
  • Now remove one wire. What happens?
  • Put the wire back.

This shows why a complete loop is needed.

Understanding circuits helps us explain how many everyday electrical devices work and why electricity needs a clear path to follow.

Power of circuits video

Free online Science games

Parts of a simple circuit

A simple circuit is made up of a few important parts that work together to allow electricity to flow. Each part has a special job.

A simple circuit usually includes:

Cell - circuit symbol

A cell (battery)

The cell provides the energy for the circuit. It pushes electricity around the loop so that the components can work. Without a cell, electricity cannot flow.

Wire - circuit symbol

Wires

Wires carry electricity from one part of the circuit to another. They connect all the components together and create the path that electricity travels along.

Bulb, buzzer & motor - circuit symbol

A bulb, buzzer or motor

These are the parts that use the electricity.

  • A bulb lights up
  • A buzzer makes a sound
  • A motor makes things move

Only one of these is needed in a simple circuit.

Switch - circuit symbol

A switch

A switch is used to control a circuit. When the switch is on (closed), it completes the circuit and allows electricity to flow. When the switch is off (open), it breaks the circuit and stops the electricity from flowing. This lets us control when a bulb lights up or a buzzer sounds.

For a circuit to work, all the parts must be connected properly. Electricity can only flow around a complete circuit. If a part is missing, loose or not connected correctly, the circuit will not work.

Conductors and insulators

Electricity can flow through some materials, but not through others. Knowing the difference helps us understand how circuits work and how to stay safe.

Conductors

A conductor is a material that lets electricity pass through it easily. Conductors are used in circuits to carry electricity from one place to another.

Most metals are good conductors. Examples include:

  • copper
  • iron
  • steel

Wires are usually made from copper because it is a very good conductor of electricity.

Insulators

An insulator is a material that does not let electricity pass through it. Insulators are used to stop electricity from flowing where it shouldn’t.

Examples of good insulators include:

  • plastic
  • wood
  • rubber
  • glass

Insulators help keep us safe. For example, electrical wires are covered in plastic so we can touch them safely without getting an electric shock.

Why this is important

Circuits need conductors to allow electricity to flow and insulators to control where the electricity goes. Using the right materials helps electrical devices work properly and safely.

Quiz ConductorsQuiz - Electrical conducators and insulators
Take the quiz and test your knowledge on conductors and insulators.
Scientist getting a shockBBC Bitesize: Conducators and insulators
Some materials let electricity pass through them easily. These materials are known as electrical conductors.

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Conductors and insulators video

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