Monday, January 17, 2011

Uses for Static Electricity

by Kokul
Although static electricity can be a nuisance—like getting shock when you touch a doorknob or having static cling on your clothes—it has a number of beneficial uses. The forces of attraction between charged particles caused by static electricity are used in air pollution control, xerography and automobile painting.
Questions you may have include:
  • How is static electricity used in air pollution control?
  • How does a Xerox machine work?
  • How is static electricity used to paint cars?
This lesson will answer those questions. There is a mini-quiz near the end of the lesson.

Pollution control

Static electricity is used in pollution control by applying a static charge to dirt particles in the air and then collecting those charged particles on a plate or collector of the opposite electrical charge. Such devices are often called electrostatic precipitators.

Smokestacks

Factories use static electricity to reduce pollution coming from their smokestacks. They give the smoke an electric charge. When it passes by electrodes of the opposite charge, most of the smoke particles cling to the electrodes. This keeps the pollution from going out into the atmosphere.
How a smokestack electrostatic precipitator works
How a smokestack electrostatic precipitator works

Air fresheners

Some people purchase what are called air ionizers to freshen and purify the air in their homes. They work on a similar principle as the smokestack pollution control. These devices strip electrons from smoke molecules, dust particles, and pollen in the air, just as what happens in creating static electricity.
These charged dust and smoke particles are then attracted to and stick to a plate on the device with the opposite charge. After a while, much of the pollution is drawn from the air.
Since charged particles will also stick to neutral surfaces, some of them can stick to the wall near the ionizer, making it very dirty and difficult to clean.

Xerography

Your photocopier or Xerox machine uses static electricity to copy print to a page. This is done through the science of xerography.
One version of this device electrically charges ink so that it will stick to the paper in the designated areas. Another version of a photocopier uses charges to stick the ink to a drum, which then transfers it to the paper.

Painting cars

Some automobile manufacturers use static electricity to help them paint the cars they make. The way this works is that they first prepare the car's surface and then put it in a paint booth. Next, they give the paint an electrical charge and then spray a fine mist of paint into the booth. The charged paint particles are attracted to the car and stick to the body, just like a charged balloon sticks to a wall. Once the paint dries, it sticks much better to the car and is smoother because it is evenly distributed.

Summary

Uses of static electricity include pollution control, Xerox machines, and painting. They use the property that opposite electrical charges attract. There are other uses involving the properties of repulsion and the creating of static electricity sparks.

Use your knowledge of static electricity to benefit mankind

Resources

The following resources provide information on this subject:

Websites

Xerography and Photocopying - references from the University of Delaware
Xerography: Chester Carlson's Impossible Dream - history of the invention of xerography
Electrostatic Precipitators for Power Plants - from Arizona State University School of Engineering

Books


Tricks for Good Grades is now available as a book.
You can purchase the book throughAmazon.com for $15.95. The Kindleversion is available for $6.95.
You can also get a PDF e-book version for only $6.25.
Tricks for Good Grades book

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Tricks for Good Grades is now available as a book.
You can purchase the book throughAmazon.com for $15.95. The Kindleversion is available for $6.95.
You can also get a PDF e-book version for only $6.25.
Tricks for Good Grades book

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Become a School for Champions Fan on Facebook.
Log in and click on the Become a Fan button.

Mini-quiz to check your understanding

1. How can static electricity help control pollution?
 By preventing lightning from starting fires
 By cleaning particles from smoke stacks
 By cleaning electrons from the air
2. How can static electricity clean out cigarette smoke?
 By giving smokers an electric shock
 By attracting cigarettes to a non-conductor
 By charging and collecting smoke particles
3. What is an advantage of using static electricity to paint a car?
 The paint goes on evenly
 The paint will attract cigarette smoke
 The paint collects at sharp points

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