Introduction to Electricity
Learn what electricity is, how circuits work, and how to stay safe around electrical power.
What is Electricity?
Electricity is a form of energy caused by the movement of tiny particles called electrons. Electrons are part of atoms -- the building blocks of everything. When electrons move along a path (like through a wire), they create an electrical current.
Think of electricity like water flowing through a hose. The battery is like a water pump, the wires are like the hose, and the light bulb is like a sprinkler that uses the water.
Two Types of Electricity
Static Electricity
A build-up of electrical charge on the surface of an object. Example: rubbing a balloon on your hair makes it stick -- that is static electricity!
Current Electricity
A continuous flow of electrons through a conductor (like a wire). This is the electricity we use to power our homes, lights, and devices.
Electrical Circuits
For electricity to flow, it needs a complete path called a circuit. A circuit must loop from one end of a power source (like a battery) through the wire and back to the other end. If there is any gap, the electricity cannot flow.
Parts of a Simple Circuit
Battery
Power source
Wire
Carries electricity
Bulb
Uses electricity
Switch
Opens/closes circuit
Electrons flow around the loop
↺
Closed Circuit (Complete)
The path is complete. Electricity flows and the bulb lights up!
Switch is ON
Open Circuit (Broken)
The path has a gap. Electricity cannot flow. The bulb stays off.
Switch is OFF
Conductors and Insulators
Some materials let electricity flow through them easily, while others block it. This is important for making circuits work and keeping us safe.
Conductors
Materials that allow electricity to pass through them easily.
- ● Metals (copper, iron, aluminium, gold)
- ● Water (with minerals in it)
- ● Graphite (pencil lead)
Wires are usually made of copper -- an excellent conductor.
Insulators
Materials that do not allow electricity to pass through them easily.
- ● Plastic
- ● Rubber
- ● Wood
- ● Glass
Wires are coated in plastic to keep us safe from the electricity inside.
Electrical Safety
Stay Safe Around Electricity!
- ⚠Never put fingers, toys, or objects into power sockets.
- ⚠Never use electrical devices near water (bathrooms, pools, wet hands).
- ⚠Never touch fallen power lines or climb electricity poles.
- ⚠If a cord is damaged or frayed, tell an adult immediately.
- ⚠Mains electricity (from wall sockets) is very powerful and dangerous. Only use batteries for school experiments.
Key Vocabulary
Circuit
A complete loop that electricity flows through, from a power source and back again.
Electron
A tiny particle that carries electrical charge. When electrons flow through a wire, we have electricity.
Conductor
A material that allows electricity to flow through it easily (e.g. copper, metal).
Insulator
A material that blocks or resists the flow of electricity (e.g. plastic, rubber).
Switch
A device that opens or closes a circuit, turning the flow of electricity on or off.
Battery
A device that stores chemical energy and converts it to electrical energy to power a circuit.
Worked Examples
A bulb is connected to a battery with wires, but the bulb does not light up. What could be wrong?
Step 1: Check if the circuit is complete. Is there a gap anywhere?
Step 2: Check if the battery is flat (no energy left).
Step 3: Check if the bulb has blown (broken filament).
Answer: The circuit might be open (a wire is disconnected), the battery might be flat, or the bulb might be broken. A complete circuit with a working battery and bulb is needed.
You test a metal spoon and a plastic ruler in a circuit. The bulb lights with the spoon but not the ruler. Why?
Step 1: The metal spoon is a conductor -- it allows electricity to pass through.
Step 2: The plastic ruler is an insulator -- it blocks the flow of electricity.
Answer: Metal conducts electricity, completing the circuit and lighting the bulb. Plastic insulates, breaking the circuit so no electricity flows.
Why are electrical wires covered in plastic?
Step 1: The metal wire inside is a conductor -- electricity flows through it.
Step 2: The plastic coating is an insulator -- it stops the electricity from reaching us.
Answer: The plastic covering keeps us safe by preventing the electricity from escaping into our bodies when we touch the wire.
Knowledge Check
Select the correct answer for each question. Click "Check Answer" to see if you are right.
Question 1
What is needed for a complete circuit?
Question 2
Which of these materials is a conductor of electricity?
Question 3
A switch is turned OFF in a circuit. What happens?
Question 4
Why is it dangerous to use electrical devices near water?
Question 5
In a circuit, what does the battery do?
Key Concepts Summary
- ●Electricity is the flow of tiny particles called electrons through a conductor.
- ●A circuit is a complete loop that electricity flows through: battery → wire → component → wire → battery.
- ●A closed circuit allows electricity to flow; an open circuit has a gap and stops the flow.
- ●Conductors (metals) let electricity through; insulators (plastic, rubber, wood) block it.
- ●Always be safe around electricity: never touch power lines, sockets, or use devices near water.