Electric Charge and Static Electricity

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Warm-Up: With a partner, discuss the
answers to this Anticipation Guide. Record
your responses on your worksheet.
1. The electricity that is in lightning is the same
electricity that is used to power appliances in your
home.
2. You can get shocked if you touch a bare wire, but not
if you touch a wire with rubber coating.
3. Electric circuits are like roller coaster rides.
4. A bird sitting on a wire can get electrocuted if it is not
careful.
5. There is no difference between a thick wire and a thin
wire when it comes to the amount of energy flow.
Electric Current
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Electric Current
• The continuous flow of electric charges through
a material.
• An amp (A) is the amount of charge that passes
through a wire in a unit of time.
Quick check: Which
characteristic of
electric current is
represented in this
‘tomato conveyor
belt’ photograph?

Electric Circuit
• A complete, unbroken path through which electric
charges can flow.
Quick check: How is an electric circuit like a toy race
track?
Conductor
• A material through
which charge can
flow easily.
Insulator
• A material through
which charge can
NOT flow easily.
Quick check: Explain why
you don’t get a shock
when you touch an
extension cord?

Charges need ENERGY to flow
• Charges in an electric circuit flow
because of a difference in electrical
potential energy.
Quick check: How is
a roller coaster like
the flow of
electricity?

Voltage
• The difference in electrical potential
energy between two places in a circuit.
• Unit of measure is the volt (V).
• Causes a current in an electric circuit.
Voltage Source
•A device that creates a potential
difference in an electric circuit.
•Ex: batteries and generators
Resistance
• The measure of how difficult it is for
charges to flow through a material
• The greater the resistance, the less
current there is for a given voltage
• Unit of measure is the ohm ( )
Quick check: If you reduce the resistance in a
circuit, will there be more or less or less current?
Explain.
Factors that Determine
Resistance
Material from Length
which wire is
made
Diameter
Temperature
Insulator =
greater
resistance
Narrow = greater
resistance
Warmer =
greater
resistance
Long = greater
resistance
Path of Least Resistance
• If electric charge
can flow through
either of two
paths, more of the
charge will flow
through the path
of least resistance.
Quick check: Why don’t the birds
get electrocuted?
Writing an Analogy:
• An analogy can help people
understand new information by
comparing it to something
familiar. Write a paragraph that
compares an electric circuit to
skiing down a slope and riding
the chairlift to the top.
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