E-Activity 16

Making use of static electricity

We can use static electricity in many different ways to do useful jobs.
1. Write down two different ways that static electricity is often used in schools and factories.
How a photocopier works
We take photocopiers for granted, but schools and offices could not manage without them. The diagrams above show, step by step, how a photocopy is made.
How to remove the dirt from smoke
Smoke contains lots of tiny bits of dirt. This dirt falls on houses and gardens. If people breathe in the dirt, it can damage their lungs.
The diagram shows how the dirt can be removed from factory chimneys using a smoke precipitator.
3. Copy and complete the sentences.
A metal grid and antenna are connected to the positive side of a high _______ supply.
The metal chimney is connected to the ______ side of the supply.
Tiny bits of dirt pick up a _______ charge as they pass through the grid. They are then repelled by the antenna and _____ by the chimney.
So the dirt collects (precipitates) on the inside of the __________ and is removed every so often.
How to make a spray hit its target
When a liquid is sprayed out of a nozzle, it becomes electrically charged. Sprays can be made to charge the droplets as much as possible. The diagrams show how this helps the spray to find its target.
4. Explain why a pesticide spray works better if it charges the droplets of pesticide.
5. Car makers want most of the paint from a spray to end up on a car body. What can they do to the car body to make sure this happens?