Ch 6, Lesson 1 and 2 ppt

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Chapter 6
Chapter 6 Lesson 1
Electric charges: tiny particles that carry units of
electricity
Energy charges that are the same: like charges
Energy charges that are different: unlike charges
Most matter is electrically neutral, which means matter
has an equal # of positive and negative charges
Like charges = repel; they push away from each other
Unlike charges = attract; they pull toward each other
Unlike charges attract
Like charges repel
Why does this happen?
Attract or repel?
repell
repell
attract
Electrically
Neutral
Negatively
Charged
Positively
Charged
Static electricity: an electric charge that build up on a
material
Example:
When running a comb through your hair (
Negative particles
Your hair loses
The comb gains
charge)
comb
charge and now has
charges and now has
charge.
charge.
Your hair and comb now have unlike charges. They
attract each other.
Each hair on your head now has a like charge. They
repel each other.
Chapter 6 Lesson 2
How charges move
The build-up of electrical particles is called static
electricity.
The constant flow of electric charges is called electric
current. This energy can be controlled and used.
electrical
current
Conductors & Insulators
 Negatively charged particles move easily through
materials called conductors. Electric current passes
easily through some metals. Copper and silver are
good conductors.
 Materials that electric charges do not flow through
easily are called insulators. Materials such as plastic
and rubber are good insulators.
 Conductors and insulators are used to control and
direct electric flow.
Conductor
Insulator
Circuits & Switches
 The pathway that an electric current follows is called
an electric circuit. A circuit is a closed pathway. This
closed, or complete pathway, has no gaps or
openings.
 If there is an opening, we call that an open circuit, or
incomplete circuit.
 Most circuits have a switch that opens and closes
the circuit.
 When you flip the switch on, you close the circuit.
The light bulb turns on.
 When you flip the switch off, you open the circuit.
The light bulb goes off.
Every working circuit has at least 3 parts:
1) A power source (battery)
2) A conductor ( usually wire)
3) An object to use electrical current
2 Types of Circuits – Series & Parallel Circuits
A circuit can have many parts. It can have a switch or
have more than one object using the electric current.
Series Circuit: a circuit with parts connected so the
electric current passes through each part along a single
path.
If you remove a
part from the
circuit, you
create an
opening.
Current will no
longer move
through any of
the parts.
Parallel Circuit: a circuit where parts are connected so
that the electric current passes along >1 pathway.
If you remove
one part from the
circuit , current
still moves
through other
parts.
http://www.youtube.com/watch?v=ajmiqpwtJ_o
What type of circuit would you want for Christmas
tree lights?
a. series
b. parallel
c. simple circuit
d. simple circuit with a switch
Draw, label, and color these circuits in your IN.
Circuits
Simple Circuit with Switch
Switch on – close the circuit; light on
Switch off – open the circuit; light off
Series Circuit
Parallel Circuit
remove a part no current
remove a part current still
moves;
>1 pathway
 Some electric objects run on batteries. A battery is
made up of one or more electric cells.
 Electric cell: an object that changes chemical
energy into electrical energy.
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