ELECTROSTATICS IN OUR EVERYDAY LIVES

WHAT IS ELECTRIC DISCHARGE?

Electric discharge is the rapid transfer of electric charges.

It usually results when a charged object is grounded.

HOW IS LIGHTNING RELATED TO STATIC ELECTRICITY? Particles within a cloud (especially a turbulent cloud) can rub

together and gain charges by friction. On a large scale, this can produce positively and negatively charged particles within the cloud.

The negative charges on the cloud fall toward the bottom and the positive charges on the cloud rise upward toward the top (induced charge separation). This causes electrons on the surface of the planet to move deeper into the earth, creating what looks like a positively charged surface.

Lightning video

HOW IS LIGHTNING RELATED TO STATIC ELECTRICITY? The high degree of charge in the cloud makes the air

better able to conduct a charge, and electrons are discharged from the cloud to the surface of the earth.

The irregular pattern of lightning is possibly due to dust or other debris in the air that interferes with electron movement.

WHAT IS AN ELECTROSTATIC GENERATOR? This is a machine that generates static electricity.

Friction between the roller C and F) and belt (D) create a charge that is transferred to the sphere (A).

HOW DOES THE CHARGE DISCHARGE WHEN YOU TOUCH THE GENERATOR?

You are a fair conductor. The charge that builds up on the surface of the generator will leave through you if you make contact with the ground.

WHAT IS THE FUNCTION OF A LIGHTNING ROD? A lightning rod protects tall structures from being hit

directly by lightning. The rod is generally taller than the structure it protects. It is connected by a grounded wire that is attached to a metal plate or pole that is buried in the ground at the base of the structure.

When lightning hits the lightning rod, the stream of electrons is directed through the ground wire, to the buried metal plate or pole, where the charge is diffused into the ground.

HOW IS CHARGE BUILD-UP REDUCED ON AIRPLANES?  Airplanes can build up a static charge from

flying through rain, snow, ice, or dust particles. When the aircraft charge is great enough, it discharges into the surrounding air from static dischargers (needle-like projections on the wings of the plane. 

WHY IS A GROUND STRAP A NECESSARY FEATURE WHEN TRANSFERRING FUEL?

When fuel moves through a nozzle it creates a build-up of static charges. This build up of charge could discharge as a spark and ignite gas fumes or the gasoline itself. A ground strap grounds the vehicle, so that the static charges do not build up, but are carried to the ground instead.

Fire at a gas pump

3 WAYS TO REDUCE STATIC CHARGE BUILD-UP ON CLOTHES Dry only one type of fabric at a time (all

cottons, or all nylons) Remove clothes from dryer before they are

completely dry Use an antistatic dryer sheet (these add a waxy

layer on the surface of clothes so they all ‘appear’ to have the same surface)

4 WAYS TO REDUCE CHARGE BUILD-UP IN A COMPUTER ROOM WITH CARPET

Use an antistatic mat

Increase the moisture in the air by using a humidifier Spray carpet with antistatic spray Wear an antistatic wrist strap Remove carpet from room

3. WHAT CAUSES A STATIC BUILDUP ON MOVING VEHICLES Friction between the vehicle and the air around

it can cause a build up of charge.

Newer tires are designed to have less resistance with the road, which can slow the removal of electrons from the surface of the vehicle with the ground.

NAME 4 APPLICATIONS THAT USE ELECTROSTATIC PRINCIPLES Photocopiers Electrostatic spray paint machines Electrostatic air filters Lightning rods Static dischargers on airplanes Grounding straps on vehicles Antistatic dryer sheets