ElectricityElectricity

A shocking story!

What do we already know about What do we already know about electricity?electricity?

In a group - brainstorm for 10 minutes - In a group - brainstorm for 10 minutes - everything that you can think of that you everything that you can think of that you already know.already know.

Choose one person as the secretaryChoose one person as the secretary Write down everything - you are Write down everything - you are

brainstormingbrainstorming..

Key QuestionsKey Questions How do objects become charged?How do objects become charged? How do positive and negative charges How do positive and negative charges

interact?interact? What is the difference between insulators and What is the difference between insulators and

conductors?conductors? What causes lightning?What causes lightning?

Static Electricity Around UsStatic Electricity Around Us What could be similar What could be similar

about a lightning storm about a lightning storm and walking across a and walking across a carpet?carpet?

What causes lightning?What causes lightning?

What gives you a zap What gives you a zap when you touch a when you touch a doorknob?doorknob?

RubbingRubbing

Ice and water droplets rub against each other Ice and water droplets rub against each other in a cloud.in a cloud.

Your shoes or socks rub against the carpet Your shoes or socks rub against the carpet when you walk.when you walk.

Why do you think rubbing might create the Why do you think rubbing might create the right condition for sparks?right condition for sparks?

ChargesCharges

Scientists have known for hundreds of years Scientists have known for hundreds of years that many materials will be attracted if they are that many materials will be attracted if they are rubbed against another material.rubbed against another material.

They used the word “ They used the word “ charged charged ” to describe ” to describe these materials.these materials.

These materials carry an “ These materials carry an “ electric charge electric charge ”” Materials that do not carry a charge are called Materials that do not carry a charge are called

“ “ neutral neutral ”.”.

Conductors and InsulatorsConductors and Insulators

Insulators - the charge stays on one spot of Insulators - the charge stays on one spot of the material.the material. Insulators do not allow the charges to move Insulators do not allow the charges to move

freely on or through the object.freely on or through the object.

Conductors - the charge is allowed to move Conductors - the charge is allowed to move freely through the materialfreely through the material Most metals are conductorsMost metals are conductors Most non-metals are insulatorsMost non-metals are insulators

So…what about rubbing?So…what about rubbing?

So…what about rubbing?So…what about rubbing?•Rubbing causes electrons to be pulled from the surface of one material and relocated on the surface of the other material.

•Rubbing a balloon on a wool sweater creates charges on the surfaces

•The material that loses electrons ends up with an excess of positive (+) charges.

•The material that gains electrons ends up an excess of negative (-) charges on its surface.