Magnetism and Electricity

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Ever Wonder How the
World Works?
Wonder Wall: Do you ever
wonder how electricity works?
How does it get to your house?
Get a sticky note. Jot down
any questions you have
about electricity.
GPS Standards
• S5P3.A- Investigate static electricity.
• S5P3.B- Determine the necessary
components for completing an electric
circuit.
• S5P3.C- Investigate common materials to
determine if they are insulators or
conductors of electricity.
• S5P3.D- Compare a bar magnet to an
electromagnet.
Unit Essential Questions
• What is static electricity?
• What are the components needed to
complete an electrical circuit?
• What are insulators and conductors, and
what are some examples of each?
• What is a magnet? How do I
compare/contrast a bar magnet and an
electromagnet?
Lesson 1: What is Static
Electricity?
EQ: What is static electricity?
Vocabulary: static electricity, electric charges,
protons, electrons, attract (attraction), and repel
(repulsion)
Let’s do an experiment! Look at your
handout, and make some predictions!
Static Electricity
Static electricity is a
buildup of electric charges
on an object. It can “jump”
from one object to another.
electric charges
Electric charges are tiny particles that
carry units of electricity. There are two
kinds of electric charges, positive(+) and
negative(-).
protons
Protons are
positively charged
particles located
inside the nucleus
of an atom.
electrons
Electrons are negatively
charged particles
circulating outside of
the nucleus.
attract (attraction)
Unlike charges attract one
another, meaning they pull
toward one another.
repel (repulsion)
Like charges repel one another, meaning
they push each other away.
Preview: BrainPop! Electricity
Read interactive textbook
pp. 140-143.
Optional: textbook
pp. 228-233
What is Static Electricity?
Static electricity is a buildup of electric
charges on an object. Unlike electricity used
in your home, static electricity doesn’t flow.
If the charge is strong enough, static
electricity can “jump” from one object to another.
The shock you feel is called a discharge.
What connection can you make from what we
have already learned?
Static electricity is what causes dust to collect on
your television screen at home!
BrainPop! Static Electricity
Where Does Static Electricity Come From?
Everything is made of matter. All the
equipment and supplies located in your
classroom are made of matter (even you).
Matter is made up of tiny particles. These
tiny particles contain different kinds of
electric charge…positive (+) and negative(-),
and neutral (no charge).
Charging an Object
When two objects rub against each other,
some electrons may move from one to the
other. The object that gains electrons will
then have a negative charge.
The other object will have a
positive charge.
So…
Charging an Object
If you rub a balloon on your hair, electrons move
from your hair to the balloon. The balloon will
have a negative charge (-). Your hair would have
a positive charge (+), because electrons have
been taken away.
If you bring the balloon near a
wall, it will stick to the wall
because the wall will have an
opposite charge (+).
Electric Force
Electric Force is the push or pull between charged
objects. Objects that have like charges repel, or
push against each other. Objects that have unlike
charges attract, or pull on each other.
Electric Force
Electric forces and magnetic forces are very similar...
opposite poles/forces attract each other. Objects do
not have to actually touch to exert either an electric
force or a magnetic force on each other.
Plasma Balls
Touch The Power Of Static Electricity And Create A
Living Work Of Ever-Changing Art
The Plasma Globe, or Inert Gas Discharge Tube, as Nikola Tesla (it's inventor) first called it,
is perhaps one of the most beautiful manifestations of plasma (4th State of Matter). Also
known as "Plasma Spheres", "Lightning Globes", "Thunder Domes", and others, these glass
spheres with dancing streams of plasma inside them have been looked at, and admired, by
people all over the world, in sci-fi movies, science museums, and even some shops.
A plasma ball is a glass globe filled with low pressure gases such as neon, argon or xenon.
An electrode is placed in the center of the globe and connected to the power supply which
gives a high-voltage, high frequency, alternating current.
Balloon Experiment
Experiment with
static electricity.
using balloons.
Tear little pieces of
paper…rub the
balloon on your
head, then hold it
near the bits of
paper. What
happens?
Have Fun!
Summarizer
In your journal, answer the following question.
Be prepared to share your answer!
A charged balloon attracts small
bits of paper. Why does this
happen? How is it like a
magnet attracting paper clips?
Think…Pair…Share!
Lesson 2: Electricity and Complete
Circuits
What Makes a Circuit?
Essential Question: What are the
components needed to complete an
electrical circuit?
Vocabulary: simple circuit, series
circuit, parallel circuit, terminal, switch
In order for electricity to flow, a closed circuit is required. The
following image shows a closed circuit with flowing electrons.
electric circuit
The pathway that electric current follows is
called an electric circuit.
pathway
Simple Circuit
Parallel Circuit
BrainPop! Electric
Circuits
Series Circuit
Simple Circuit
The simplest electric circuit needs an energy source and a
material that electrons can easily flow through. All
components need to be connected to complete the circuit.
series circuit
The parts of an
electric circuit are
connected so that
electric current
passes through each
part, one after
another, along a
single pathway.
Series Circuit
In a series circuit, the electric current flows in a single path…
first through one bulb (or battery), then through the next. The
more bulbs that are connected in series, the more dimly all will
glow. If one bulb burns out or is removed, all the bulbs in the
series go out (because the path would be broken).
Parallel Circuit
•In a parallel circuit, the different parts of the circuit are connected in
separate branches. The electric current travels to each branch.
•A parallel circuit is more difficult to put together than a series circuit, but it
has an advantage.
•What is the advantage?
If one path (branch) is broken, the current will continue to move along another path!
If there are multiple bulbs connected in a parallel circuit and one bulb burns
out…the other bulbs will stay lit because they will continue to receive the electric
current passing through the wires.
parallel circuit
The parts of a parallel circuit are connected
so that electric current passes along more
than one pathway.
Battery or Energy Source
Object that uses the energy
The Switch
Conductor…usually wire
Please note that a circuit can still be
complete without a switch. The switch is for
convenience of turning the circuit on or off.
The Battery or Energy Source
A battery is an energy source often used in a circuit. It
provides the “push” to keep electrons moving in
a circuit. A simple battery has two parts. One part tends
to give up some of its electrons. The other part tends
to take in electrons. If you connect the ends of a wire
to the top and bottom of a battery, electrons will flow
through the circuit. A terminal is a place on a battery
where electrons go in or out. Often, the positive
terminal, where the electrons go in, is on top. The
negative terminal is on the bottom. Some batteries
have both terminals on top.
BrainPop! Batteries
The Conductor…Usually Wire
The wire used in a circuit is often made of copper. Copper is a
metal. The electrons can easily move from atom to atom in a
metal. The wire should have a plastic or rubber coating on it.
The electrons cannot easily go through the coating. It lets you
safely touch the wire.
The Switch
A switch is a device that can open or close a circuit.
The bulb in this picture is not lit
because the switch is flipped up.
An open circuit is an electrical
path that is not complete.
Electrons will not flow when the
circuit is open.
The bulb in this picture is lit
because the switch is down. The
circuit is closed and the circuit is
complete. A closed circuit allows
electrons to flow.
The Bulb or Object to Receive the Energy
Most circuits have more in them than just a wire
and battery. For example, imagine a circuit that
has a bulb. A bulb has a thin wire called a filament
inside. This wire is so thin that electrons can
hardly pass through. When they do, the wire
becomes hot. It begins to glow. This glow is the
light you see from a bulb.
Adding To and Taking Away
with Simple Circuits
You can add more bulbs to a simple circuit. Current
will flow first through one bulb and then through the other.
Devices such as bulbs or buzzers resist the flow of electrons.
Adding an extra bulb to a circuit resists the flow even more. As
a result, two bulbs in a circuit glow less brightly than one bulb
alone does. A switch does not resist the flow of electrons.
Taking a switch out, or adding another switch, will not affect
the brightness of the bulb.
What do you think would happen if you remove the battery or if
you remove one of the bulbs?
Junior Electrician: Current Electricity (15 min.)
United Streaming Video Presentation
Problems? Look in the folder for the video.
Summarizer
In your journal…
Reflect on the experience of building
electrical circuits. What procedures did
you follow? Were you able to build a
“working” simple circuit? Did you have
any problems?
Explain and draw a picture to demonstrate
how a simple circuit works!
Lesson 3:
Conductors and Insulators
Lesson 3: Conductors and
Insulators
EQ: What classifies a material as a
conductor or insulator of electricity?
What are examples of each?
Vocabulary: conductor, insulator, electric
current (electricity)
electric current (electricity)
An electric current is the flow; or movement, of
negative charges through a material.
Movement of
electrons along
the electric
pathway!
What is Electric Current?
For electricity to be useful, it must be moving continuously. So static
electricity is not very useful. Negative charges can move freely from
place to place in a solid. An electric current is the flow; or
movement, of negative charges through a material. The energy
provided by the moving charges is called electrical energy, or simply
electricity.
Electricity can be used to do work. However, the energy of the
moving charges that make up electricity must be controlled. You must
be able to make electricity move and stop moving when you want.
And you must be able to control where it goes.
When you plug something into an outlet, you tap into an
electric current. The electricity flows through the plug
and into the object you plugged in
BrainPop! Current Electricity
What is Electric Current?
Once electricity reaches the place where it is to be used, it is
changed into some other kind of energy, such as light in a lamp,
heat in a toaster, or motion in a fan.
Think about how energy is used and controlled in the school.
Cords are plugged into outlets. Switches are flipped, and electric
charges move or stop moving through wires. Dials and knobs are
turned to change the amount of
charge that moves through the
wires. This is controlled energy.
Electricity being used in the home.
Conductors
Wires are the pathways through which negative charges flow. Wires are
made of materials that carry these charges. A conductor is any
material that allows negative charges to move through it. Metals make
the best conductors. Copper is the most common metal used for that
purpose. The wires used in your school and in your home are probably
made of copper.
You may be familiar with the expression “live wire.” The
word live is used to describe any conductor in which
charges are moving. Moving charges can be dangerous.
Your body is a good conductor. If you were to touch a live wire, the
charges in the wire would move through your body and you would
receive an electric shock. If the wire is carrying enough current, the
shock can cause serious injury, or even death.
conductor
A conductor is any
material that allows
negative charges to
move through it. Metals
Watch
make the best
http://www.youtube.com/w
conductors.
atch?v=-wj2Oh50wsA for a
video clip from A
Christmas Story (tongue
on pole) to show heat
transfer.
People are good conductors of electricity, especially if they are in contact with water
on a damp floor or ground. Never use an electric appliance in a tub, shower or
pool. Never touch an electric cord or appliance while your hands are wet.
Insulators
Negative charges do not flow freely through some materials. These
materials are called insulators. Some good insulators are rubber, wood,
glass, and certain plastics. To make electricity safe to use, conductors and
appliances are covered with an insulator. This covering is called insulation.
The negative charges can continue to move freely through the conductor,
but the insulation will protect a person from the live wire.
As long as negative charges have a complete path to follow, they will
continue to move through a conductor. But where do all these negative
charges come from? Somewhere, there is a device that provides a
steady supply of negative charges. It may be a huge
generator at an electric power plant, or it may be the
chemicals in a tiny cell that runs a wristwatch or calculator.
The metal cables and metal clips of the jumper cables
are conductors. You are protected by rubber insulation.
insulators
• Materials that electric charges do not flow
through easily are called insulators.
In your journal…Sort the following items as
conductors or insulators of electricity.
Discuss with a partner. Can you think of others?
Other Resources to Explore
Quia - Electricity: Conductors and Insulators
Matching Game
Lesson 4: Magnets
“Bar Magnets and Electromagnets”
Lesson 4:
Bar Magnets Vs. Electromagnets
Essential Question: What are bar magnets
and electromagnets, and how can I compare
and contrast them?
Vocabulary:
magnet, magnetic field, electromagnet,
generator, and motor
Just What are Magnets?
A magnet is an object that can push or pull on iron and a
few other kinds of metal without touching the metal.
Each end of a magnet is called a pole. The poles of a
magnet are usually labeled N for north and S for south.
Some magnets have a bar shape. Magnets with a U shape are called
horseshoe magnets.
If the north poles of two magnets
are close, the magnets repel, or
push apart. The magnets also repel
if the south poles are close. If a
north pole and a south pole are
positioned toward each other, the
magnets attract, or pull together.
magnet
A magnet is an object that attracts iron and
certain other metals.
magnetic poles
The force of a magnet
is greatest at two
areas called the
magnetic poles.
Magnetic Field
A magnetic field is the area around a magnet where it can
push and pull on other magnets. A magnetic field is all
around a magnet, but it is strongest at the poles. The push
or pull from a magnet is strongest close to the magnet. The
strength of the field is weaker farther from the magnet.
BrainPop! Magnetism
Did you know?
• No matter how many times
a bar magnet is cut in half,
there is always a north and
south pole, even in the
smallest piece.
generator
A generator is a device that
uses magnetism to
convert energy of motion
into electrical energy.
motor
An electric motor is a device that changes
electrical energy into energy of motion.
Inside of a motor
http://www.physics.uiowa.edu/~umallik/adventure/nov_06-04.html
Electromagnets
Magnets and electricity are related. An electric current produces a magnetic
field. When a current flows through a wire, a magnetic field surrounds the
wire. If you form the wire into loops, the magnetic field is like that of a bar
magnet.
Just like a magnet, the wire loops with a current have a north pole and south
pole. The magnetic field is strongest at the poles. You can increase the
strength of the magnetic field if you add more loops. You can also increase
the field if you increase the current in the wire.
BrainPop!
Electromagnets
electromagnet
An electromagnet is a
strong temporary
magnet that uses
electricity to produce
magnetism.
Making an Electromagnet
An electromagnet is a magnet made by
winding a wire with a current around an
iron bar. When the iron bar is placed in
the looped wire, the iron itself has a
magnetic field. This makes the field of the
looped wire stronger.
You can make an electromagnet if you
loop wire around an iron nail and attach
the ends of the wire to a battery. The
current in the wire will cause the iron
and wire to be a magnet. You can then
use the electromagnet just as you would
use a bar magnet. It will attract paper
clips and other iron objects.
Did you know you already use
electromagnets ?
Electromagnets are found in
may devices. Doorbells,
computers, audio speakers,
and telephones have
electromagnets in them. A
crane uses an electromagnet
to pick up heavy loads of iron
or steel. A wire coil in an
electric motor spins because it
is an electromagnet.
Comparing a Bar Magnet and an
Electromagnet
Think about what you have
learned about basic
bar magnets and
electromagnets.
How are these magnets
similar?
Comparing a Bar Magnet and an
Electromagnet
1. Both types of magnets have a
north and south pole.
2. The field around them is strongest
at these poles.
3. They both attract iron filings and
other magnetic objects.
Advantages of Electromagnets Over Bar Magnets
They can be turned on and off by turning the current on and off.
They can be made stronger or weaker by either changing the
strength of the battery or by changing the number of wire loops.
The direction of the field can be changed (switching the poles) by
switching the ends attached to the battery.
Magnets (17 min.)
United Streaming Video Presentation
Problems? Look in the folder for the video
.
Let’s Try to Build an Electromagnet
Use the handout provided in class to build
an electromagnet!
Summarizer
In your journal…
Draw a picture of a bar
magnet and an
electromagnet.
Describe the similarities
between the two
magnets.
https://www.vtunnel.com/index.php/1010110A/ecbc83adfa346c8e3be5486d78a1d6130682de97e95b4bfb2cc1249de2b5a6d5cfb68c7525821323c0c
d8039616e213d888652bcb8ed721275c0086d95342c18696
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