Transcript Electricity

Electricity & Magnetism
Chapter 1 - Electricity
8th Grade
What is Electricity and Magnetism?
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On a post it, write how we use electricity.
On a post it, write how we use
magnetism.
Positive and Negative Charges
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How do charged particles
react to one another?
Protons – positively
charged, found in the
nucleus
Neutrons – no charge,
found in the nucleus
Electrons – negative
charge, found in the
electron cloud
Section 1 – Electric Charge
More about the atom
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All atoms have a neutral charge.
Same number of protons, neutrons, and
electrons
If an atom becomes charged, it is called
an ion.
Ions can be positively charged or
negatively charged.
Section 1 – Electric Charge
How do objects become charged?
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It is easier for an atom to lose electrons.
When solid objects are rubbed together,
electrons transfer from one object to
another.
Examples:
- balloon to hair
This buildup of electric charge is called
static electricity.
Section 1 – Electric Charge
Ions move through solutions
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Sometimes the movement of ions causes a
flow of charge.
This happens in our bodies to help
different parts communicate with one
another.
In this flow of charge, ions are moving,
not electrons.
Section 1 – Electric Charge
Electric Forces
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Electric forces can be attractive or
repulsive.
Electric force gets stronger as the distance
decreases.
Electric charges exert a force on each
other at a distance through an electric
field.
Section 1 – Electric Charge
Insulators and Conductors
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Electrons cannot
move easily through
insulators.
Plastic, wood, rubber,
glass
What are some uses
of insulators?
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Electrons can move
easily through
conductors.
Metals
What are some uses
of conductors?
Section 1 – Electric Charge
Induced Charge
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Have you ever played the static game with
your siblings?
Rub your feet (with socks) on carpet, and
then go and touch another surface.
You get a shock (electric discharge)
because of induced charge.
Lightning is an example of electric
discharge.
Section 1 – Electric Charge
Grounding
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Process of providing a pathway to drain
excess charge into Earth.
Small amounts of electric discharge and
create problems with circuits (computers).
Lightning rods are examples
Section 1 – Electric Charge