MOVING & USING STATIC CHARGE

Text 10.1-10.2: Page 400-411

Agenda

1. Review of Static Charge2. Moving Charge

Different Materials Contact Charge Induction Charge Grounding Electric Discharge

3. Electroscope Review Activity

Learning Goals

By the end of this class, we should be able to Compare and contrast insulators and

conductors Compare and contrast static, contact and

induction charge Complete an investigation to test types of

current charge and conductivity of materials

Reviewing Static Electricity

Materials

Materials can be grouped by weather they allow charge to move through them Insulators and Conductors

are groupings determined by their conductivity

Conductivity is the ability of materials to allow Martials to allow electrons to move freely in them.

Insulators

Material that hold onto their electrons and do not allow them to move easily are called electrical insulators

An insulator is a solid, liquid or gas that resists or blocks the movement of electrons EX: dry wood, glass and plastic

Conductors

Materials that allow electrons to change positions are called conductors Conduction is the

movement or transmission of electrons through a substance

Ex. Copper and aluminum

Somewhere in the Middle?

Some materials only allow some movement of electrons These are called fair

conductors Sort of like an insulator, sort

of like a conductor NOTE: only PURE water is

an insulator Most water has minerals in it

so it is considered a fair conductor

Let’s Test It – Conductivity Test Assemble the

electrical conductivity apparatus.

Test conductivity of different samples.

How Can You Test For Charge? You can use an

electroscope This is an instrument used

to detect electric charge Metal-Leaf electroscope

has a two very thin metal pieces called leaves suspended from a metal rod.

The metal rod is then attached to a top plate or metal knob

What Would Happen If? +

What Would Happen If? -

Contact Charge

This is an example of Contact Charge This can also be

called charge by contact

The charge is made through contact with another charged object

Induction Charge

This is very similar to contact charge Is the movement of

electrons between objects close by but not in direct contact

EX: you can statically – charge a balloon by rubbing it on your hair Put the balloon near a wall

and it will attract to it! No contact is made

Grounding

Grounding is the process of connecting a charged object to the earth’s surface This creates a path for

the electrons to travel to the ground

“Escape route” for electrons which removes charge

Electric Discharge

When electrons find an escape route and they transfer very quickly it is called electric discharge Sparks are an

example Sparks are a

transfer of charge by induction

Electric Discharge

Lightning is a very large example or electric discharge

Inquiry Question – Which way does a lightning bolt travel?

http://www.youtube.com/watch?v=l9kVA6aY5P8

Electroscope Lab

Using Static Charge

Pick a group of 2-3(max.) Choose a topic:

Lightning rods (p.g. 418) Static charge on vehicles (p.g. 419) Reducing static charge at home & work (p.g.

420) Spray Painting (p.g. 421) Photocopying (p.g. 422) Enviromental Applications (p.g. 423)

Summarize your findings using words & text Final Round = Static Charge Walk About