Download Electricity

Key Vocabulary
• Ion – is a positively or negatively charged
atom.
• Static Charge – this is an imbalance of
electric charge on an object.
• Electric Force – this is an attractive or
repulsive force exerted by all charged
objects on each other.
Key Vocabulary
• Electric Field – this surrounds every
electric charge and exerts forces on other
electric charge.
• Insulator – Is a material in which electrons
cannot move easily.
• Conductor – is material in which electrons
can move or that transfers heat easily.
Key Vocabulary
• Electric Discharge – is rapid movement of
excess charge from one place to another.
• Electric Current – is the flow of electric
charge, measured in amperes.
• Circuit – is closed conducting loop in
which electric current can flow continually.
• Voltage – is a measure of the amount of
electrical potential energy in a flowing
electric circuit can get.
Key Vocabulary
• Resistance – is a measure of how difficult
it is for electrons to flow in a material.
• Ohm’s Law – states that the circuit equals
the voltage divided by the resistance in the
circuit.
• Series Circuit – is a circuit that has only
one path for electric current to flow.
Key Vocabulary
• Parallel Circuit – is a circuit that has more
than one path for electric current to flow.
• Electric Power – rate at which electrical
energy is converted into other forms of
energy, measured in watts or kilowatts.
• Load – is a device in a circuit that operates
using electrical energy.
•
Key Vocabulary
• Resistor – is an object added to a circuit
that restricts the flow of electrical energy.
• Switch – is a device that is used to control
the flow of current through a circuit.
What are Ions?
An atom that is positively or negatively
charged because it has gained or lost
electrons.
Plasma is made up of ions.
Static Charge
• An imbalance of electric charge on an
object.
Example
When we rub a balloon to our head, what happens?
The atoms in your hair hold their electrons more
loosely than the atoms on the balloon. Electrons
from the hair travel to the surface of the balloon.
The hair becomes positively charged, while the
balloon becomes negatively charged.
“OPPOSITES ATRACT!”
Electric Forces
• This is an attractive or repulsive force
exerted by all charged objects on each
other.
“OPPOSITES ATTRACT”
Electric Field
• This surrounds every electric charge
and exerts forces on other electric
charge.
• Gets stronger as you get closer to a
charge.
+
The electric field arrows point away
from a positive charge.
-
The electric field arrows point toward
a negative charge.
Insulators & Conductors
• A material in which electrons cannot move
easily from place to place is an insulator.
• Materials that are conductors contain
electrons that can move more easily in the
material.
Electric Discharge
• Is a rapid movement of excess charge
from one place to another.
• Lightening is an example of Electric
Discharge.
Electric Current
• Is the flow of electric charge, measured in
amperes.
Solids – Flowing charges are electrons
Liquids – Flowing charges are ions (Positively
or negatively charged)
Circuit
• Is closed conducting loop in which electric
current can flow continually.
• Usually has a resistor, load, & switch.
Series Circuit
• Is a circuit that has only one path for
electric current to flow.
• Lets use a circuit with 2 light bulbs as an
example, if one light bulb goes out the
other goes out. You could say they go out
in a “SERIES”.
Parallel Circuit
• Is a circuit that has more than one path for
the electric current to follow.
• Lets use 2 light bulbs as an example, if
one goes out the other will remain to glow.
Resistance
• Is the measure of how difficult it is for
electrons to flow through a material.
• Insulators will have a higher resistance
than conductors.
Ohm’s Law
• States that the circuit equals the voltage
divided by the resistance in the circuit.
• Voltage = Current x Resistance
(in volts)
(in amperes)
(in ohms)
• When voltage in a circuit increases the
current increases, or if the voltage does
not change the current decreases.
Question using Ohm’s Law
A Light bulb is plugged into a wall
outlet. If the light bulb has a resistance of
200
and the current in the light bulb is
1.5 A, what is the voltage provided by the
outlet?
Answer is…
Electric Power
• Rate at which electrical energy is
converted into other forms of energy,
measured in watts or kilowatts.
• Power = Current x Voltage
(in watts)
(in amperes)
(in volts)
Question
A light bulb is plugged into a 205- V wall
outlet. How much electric power does the
light bulb use if the current in the bulb is
2.61 A?
Answer is…
Credits
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Crct Coach Book
8th Grade Science Book
Google pages
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