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The universe is made up of positive
particles (protons) and negative
particles (electrons)
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The Fundamental Rule of Electricity:
like charges repel and unlike charges
attract.
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What is the force that causes the
particles to attract or repel each
other?
Electrical
Force
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I understand the concept of “charge”
and can explain the relationship
between positive and negative
charges.
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Charge is a property of the particles:
Protons are positively charged and
Electrons are negatively charged
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1. Every atoms is made up of a
positively charged nucleus
(center) surrounded by negatively
charged electrons
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2. Electrons are all identical – they
have the same mass and the same
amount of charge
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3. The nucleus has protons and
neutrons.
- Neutrons have no charge.
- Protons have much more mass
than electrons but an equal
amount of charge.
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Most atoms have the same
number of protons and electrons,
but electrons can be gained or
lost.
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“Charging Ahead”
Demonstration
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What does “Conservation” mean?
What was Conservation of Matter?
How about Conservation of Heat?
Can you guess what Conservation of
Charge is?
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When something is
“charged”, no electrons
are created or destroyed
– they are simply
transferred from one
material to another.
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When electrons move to an object,
that object is said to have a negative
charge (more electrons)
When electrons move away from an
object, that object has a positive
charge (less electrons)
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The proton is the nucleus of the hydrogen
atom, and it attracts the electron that
orbits it. Relative to this force, does the
electron attract the proton with
a. less force,
b. more force or
c. the same amount of force?
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Yesterday, with the popcorn, in some
cases, you saw the popcorn move
even though the nail wasn’t touching
the popcorn and the balloon or plastic
strip wasn’t touching the nail…
Why would this happen?
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Just like with gravity, electric forces
are affect things that are not in direct
contact with each other.
We call the area where the force is in
affect a force field.
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An electric field is the area around a
particle with a charge.
Just like with gravity,
the farther away the
weaker the force
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What is potential energy?
Potential Energy
is the energy
due to position
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Which has more
Electric Potential?
B
+
+
B because it
is closer to
the field
A
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Which has more
Electric Potential?
B
+
+
B because it
is closer to
the field
A
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It takes more work to
move the charged particle
+
closer to the field…
What if the amount of
charge is greater?
Will more or less work be
needed?
More!
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With electricity, instead of
considering the total
+
potential energy, it is
easier to look at how
much energy is per charge
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Voltage is the measure for
electric potential per charge
Volts are the unit for voltage
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What does it mean to say that
your car has a 12-volt battery?
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Today’s learning goal:
I understand the concept of “charge” and
can explain the relationship between
positive and negative charges.
Using the scale, how do you think you are
doing with the concept?
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Heat