Science
What is static electricity?
Quick answer
Static electricity is a build-up of electric charge on an object, often from rubbing. It makes hair stand up, balloons stick to walls and, on a huge scale, lightning.
In one sentence
Static electricity is electric charge that builds up on a surface and stays there until it can escape, often with a small spark.
Explained
All materials are made of atoms. Atoms contain tiny electrons with a negative charge, and a centre with a positive charge. Usually the charges balance, so the object is neutral. But when two different materials are rubbed together, electrons can move from one to the other. One object ends up with extra electrons (a negative charge), and the other is short of them (a positive charge). This build-up of charge that stays in place is static electricity.
balloon
lightning
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The rules are simple. Opposite charges attract. Like charges repel. Rub a balloon on your hair: the balloon gains electrons and becomes negative, and your hair becomes positive. Your hair is pulled toward the balloon, so it stands up. The charged balloon is also attracted to a neutral wall, so it sticks.
Other examples:
- A plastic comb or ruler rubbed on wool picks up small bits of paper.
- You may get a small zap from a door handle after walking on a carpet or sliding down a plastic slide.
- Clothes crackle and cling together when they come out of a tumble dryer.
Lightning is static electricity on a gigantic scale. Inside storm clouds, ice and water bump together and charge builds up. When it is big enough, it jumps to the ground or to another cloud as a flash. The air around it heats up suddenly and makes the bang of thunder. In a thunderstorm, stay indoors or in a car, and keep away from open fields, water and tall trees.
Static electricity is different from the current in a wire. In a circuit, charge flows continually. Static charge stays put until it leaks away or jumps. In some places, static is a danger: fuel tankers are earthed so that sparks cannot light the fuel. It is also useful in photocopiers and in paint sprayers. See electricity and compare with magnets, which also attract and repel.
Examples
| Situation | What happens |
|---|---|
| Balloon on hair | hair rises, balloon sticks to wall |
| Comb and paper | small pieces jump to the comb |
| Door handle zap | charge jumps to your finger |
| Thunderstorm | lightning discharge |
Common mistakes
- "Static electricity is a different kind of electricity." It is the same charges, just not flowing.
- "Charging creates new electrons." They move from one object to another.
- Standing under a tree in a storm. Go indoors.
Quick quiz
Static electricity
Check what you know with 4 quick questions.
Question 1 of 4
What happens when you rub a balloon on your hair?
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Related topics
Electricity
Electricity is the flow of tiny charged particles called electrons through a material. It powers lights, phones and machines, and it can come from batteries or the mains supply.
Magnets
A magnet is an object that pulls on certain metals, such as iron, and pushes or pulls on other magnets. Every magnet has a north pole and a south pole.
Forces
A force is a push or a pull. Forces can make things start moving, speed up, slow down, change direction or change shape. They are measured in newtons.
Electric circuits
An electric circuit is a complete loop that electricity flows around. A simple circuit has a battery, wires and a component like a bulb. If the loop is broken, the electricity stops.
Energy
Energy is what makes things happen: it makes things move, heat up, light up and grow. It cannot be created or destroyed, only changed from one form to another.
Friction
Friction is a force that acts when two surfaces rub or slide against each other. It slows things down and turns movement into heat, and it also stops us slipping.