1. Electric Charge and Static Electricity
Unit 7, Lesson 3

2. Accessing Prior Knowledge
Discuss…..
What particle of an atom has a negative charge?
 What are forces?
 Give an example of a force that acts over a distance.

3. Electric Charge
Electric charge- a property that leads to electromagnetic interactions between the particles that make up matter
Can be a positive charge, a negative charge, or no charge

4. Ion: when an atom is negatively or positively charged

5. What affects the electric force between two objects?
Any two charged objects exert a force on each other called an electric force
This is like gravity- they act on each other without touching
However, gravity is only a pull, electric force can pull OR push
Charge
Like charges repel, opposite charges attract
The amount of charge effects the strength
Distance
The distance between the two objects effects the size of the electric force-
Closer together = stronger force

6. How can an object become charged?
Objects become charged when their atoms gain or lose electrons. The three ways this can happen are…
By Friction
When two objects are rubbed together- this causes a transfer of electrons between the objects
EX: rubbing a balloon on your head
By Contact
If a charged object and an uncharged object touch, the charged object can transfer some of its charge to the area it touches
EX: hair standing up when touching a Van de Graaff generator
By Induction
Rearranging the charges in an object without touching it.
EX:

7. What is static electricity?
Static electricity- the extra buildup of electric charge on an object
Charges that build up as static electricity eventually leave the object. This is known as Electric discharge
EX: Lightning
Brain Pop- Static Electricity

8. What materials affect the flow of charge?
Conductors
A material through which charges can move freely
EX: metal
(mostly copper is used in wires)
Insulators
A material through which charges can NOT move freely
EX: Plastic, rubber, glass, and dry air
(plastic is used on the outside of wiring)
Semiconductors
Materials are able to control the flow of charge.
Used to process electrical signals in different ways
EX: Silicon (computer chips)

9. How is charge conserved?
Atoms gain or lose electrons from other objects
Electrons are not really lost, they are transferred
Electrons can not be created or destroyed