Magnets

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Ever see this?
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Winter migration..

• Canadian geese every year travel from the north
  into our region. They tend to follow predictable
  routes and patterns.
• How do they find their way to where they are
  going?
• As a group develop possible explanations for how
  they navigate. 2 minutes
• Write down your explanation

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Winter migration..

• Using your devices, books, and articles gather
  more information regarding this topic.
• SSW Based on your new information adjust your
  answer accordingly.
• What did you find??

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SSW

• On your notes make a list of EVERYTHING you know
  about magnets/magnetism (no matter how small or
  trivial).

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Magnets

• Day 2

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Magnetism

• What makes a magnet unique?
• Objects that produce fields that attract or repel
  other objects.
• What are the two ends of a magnet called?
• Poles, North () and South (-)
• What is attracted to a magnet?
• Opposite poles (N to S or S to N)
• Certain metals like Iron, steel, nickel, and
  cobalt
• What is repelled by a magnet?
• Same poles repel (N to N or S to S)

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Magnetism

• What is a magnetic field?
• magnet where the force of the magnet can act.
• Can we see the magnetic field?
• Not directly
• How do we know the field exists?
• We can see how it affects other objects.

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How does it work?
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• Remember everything that is matter has charges in
  them. However until those charges line up or move
  in the same direction they have very little
  force.

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Magnetic Force

• With the charges lined up it creates a greater
  amount of force that can react at a distance.

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Magnets

• Day 3

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Review

• What are magnets attracted to?
• What are the name of metals that are attracted to
  magnets?
• What are magnets repelled by?
• What is a magnetic field?
• What gives a magnet its force?
• How do we know there is a magnetic field if we
  cant see it?
• Draw a diagram of the magnetic field lines of a
  bar magnet?

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.we still didnt solve yesterdays problem

• How do we solve which side of your round magnets
  are really North or South?

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• Compass

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• Field lines of earths magnetic field come
  together close to the planets North and South
  poles.
• The north-seeking pole of the free-moving magnet
  in the compass points to Earths magnetic North
  Pole.

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Bird Migration Video

• https//www.youtube.com/watch?v4JUYyMHOHb8
• https//phet.colorado.edu/en/simulation/magnets-an
  d-electromagnets

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Types of Magnets

• There are three types of magnets.
• Permanent
• Temporary
• Electromagnet

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Permanent Magnets

• These are naturally occurring pieces of a mineral
  called magnetite. It also has another name known
  as lodestone.
• Key features
• Naturally occurring
• Magnetic field cannot be turned off
• Magnetic field has a specific direction
• Must add more magnets to increase the field
  strength

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Magnets

• Day 4

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Types of Magnets

• There are three types of magnets.
• Permanent
• Temporary
• Electromagnet

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Permanent Magnets

• These are naturally occurring pieces of a mineral
  called magnetite. It also has another name known
  as lodestone.
• Key features
• Naturally occurring
• Magnetic field cannot be turned off
• Magnetic field has a specific direction
• Must add more magnets to increase the field
  strength

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Temporary Magnets

• These are pieces of iron, steel, or cobalt that
  have been temporarily turned into a magnet.
• Key features
• Occurs when a permanent magnet is rubbed along a
  piece of iron, steel, or cobalt
• Magnetic field cannot be turned off, however it
  doesnt last long
• Magnetic field has a specific direction which is
  determined by the permanent magnet.
• Field strength is determined by strength of
  permanent magnet used on it.

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What about a temporary magnet?
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Electromagnet
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What is electromagnetism?

• (1820) Hans Christian Oersted produced a current
  in a wire during a lecture.
• When he brought a compass near the wire, the
  compass changed direction.
• Whenever he turned on the current in the wire,
  the compass needles lined up around the wire in
  the shape of a circle.

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Electric Current Magnetism

• Wherever there is electricity, there is magnetism
• An electric current produces a magnetic field
• This relationship is called electromagnetism

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What do they look like?

• An electromagnets can be made out of a variety of
  materials but they all have the following
• Voltage source (battery or other source)
• A ferromagnetic core
• Wire wrapped around the
• core. This is known as a
• solenoid.

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As You Enter (no notes)

1. What does ferromagnetic mean?
2. Why does a compasses north needle face the south
   end of a magnet?
3. What happens inside an iron nail when you rub it
   against a magnet?
4. What is electromagnetism?

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Magnets

• Day 5

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Electric Current Magnetism

• Wherever there is electricity, there is magnetism
• An electric current produces a magnetic field
• This relationship is called electromagnetism

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What do they look like?

• An electromagnets can be made out of a variety of
  materials but they all have the following
• Voltage source (battery or other source)
• A ferromagnetic core
• Wire wrapped around the
• core. This is known as a
• solenoid.

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Electromagnet

• The magnetic field produced by electrical current
• Key Features
• The field can be turned on and off
• The field can have its direction reversed
• The field can have its strength changed

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Electromagnet

• You can turn a magnetic field produced by a
  current on and off
• How can you turn the magnetic field off?
• Simply by turning the current off!

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Electromagnet

• You can change the direction of a magnetic field
• How can you change the direction?
• Simply by reversing the direction of the current!

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Phet
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Electromagnet

• You can increase the field of an electromagnet.
• Increase the current in the solenoid
• Add more loops of wire to the solenoid
• Wind the coils of the solenoid closer together
• Increase the strength of an electromagnet by
  using a stronger ferromagnetic material for the
  core

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Magnetic Levitation

• Mag Lev
• Day 6

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Mag Lev

• Using the 2nd Law of Electric Charges, Like
  charges repel, we can create things that float or
  levitate.

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Mag Lev

• https//www.youtube.com/watch?v1gMMM62NC-4

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Mag Lev

• More than just a parlor trick. Has been used to
  reduce friction in trains. MagLev trains do not
  have wheels, instead they have magnets that lift
  the train slightly so it floats. This means less
  friction which means it can go really fast
  (268mph).
• https//www.youtube.com/watch?viaElPV0FWJ0

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Standing Review

• What is a magnet?
• Where is the greatest force on a magnet?
• What is attracted to a magnet?
• What metals are ferromagnetic metals?
• What is repelled by a magnet?
• If we cant see a magnetic field, how do we know
  it exists?
• What gives a magnet its field?
• What does the field around a magnet look like?

• Why does the north end of compass needle face the
  south end of a magnet?
• Does a compass point to geographic north-ish?
• Where could we find a permanent magnet?
• Can we turn the field off on a permanent magnet?
• Can we switch the poles on a permanent magnet?
• Can we increase the strength of a permanent
  magnet?
• What is a temporary magnet?

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Standing Review

• What happens inside a temporary magnet?
• Why doesnt a temporary magnet stay magnetized
  very long?
• Can I turn the field off and on in a temporary
  magnet?
• How can I switch the poles of a temporary magnet?
• How can we increase the strength of a temporary
  magnet?
• Why does a compass line up with a wire that has
  electrical current?
• What is electromagnetism?

• What are the parts of an electromagnet?
• How we turn the field of an electromagnet off or
  on?
• How can we switch the poles of an electromagnet?
• What are the 4 ways we can decrease the strength
  of an electromagnet?

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Magnets
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Mixing the two

• Lets look at what happens when we mix an
  electromagnet and a permanent magnet.

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Electric Motors
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Electric Motor

• An electromagnet is the basis of an electric
  motor
• An electric motor is all about magnets and
  magnetism A motor uses magnets to create motion.
  
• An electrical current running through a wire
  while inside a magnetic field causes motion.
• Opposites attract and likes repel. Inside an
  electric motor, these attracting and repelling
  forces create rotational motion.
• A motor is consist of two magnets.

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Vertical position of the loop
Rotation
N
S
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• https//www.youtube.com/watch?vQ2mShGuG4RY
• https//www.youtube.com/watch?vLAtPHANEfQo

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TRANSFORMERS
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Why do we need transformers?

• In most cases, machines and appliances using
  electricity are manufactured to operate using a
  specific voltage and frequency. However, not all
  countries- and sometimes not all regions within
  the same country- generate the same voltage and
  frequency in their electricity.

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TRANSFORMERS

• This is where transformers come in. Transformers
  adjust the voltage coming into the appliance to
  the proper level, and move it through the
  appliance to keep it running properly.

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TRANSFORMER

• A transformer can change electrical energy of a
  given voltage into electrical energy at a
  different voltage level. It consists of two coils
  arranged in such a way that the magnetic field
  surrounding one coil cuts through the other coil.
• Transformers can step up the voltage or step it
  down.
• We step up voltage to send it over long distances
• We step down voltage in order to use in houses

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This transformer's job is to reduce the 4160
volts down to the 240 volts that makes up normal
household electrical service. It is a step down
transformer
                                                                                   
http//science.howstuffworks.com/power3.htm
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Step Up Transformer at Power Plant
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TRANSFORMER

• The factor which determines whether a transformer
  is a step up( increasing the voltage) or step
  down (decreasing the voltage) type is the "turns"
  ratio. The turns ratio is the ratio of the number
  of turns in the primary winding to the number of
  turns in the secondary winding.

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Step-up Transformer
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http//www.ibiblio.org/kuphaldt/electricCircuits/A
C/AC_9.html
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• https//www.youtube.com/watch?vZjwzpoCiF8A
• https//www.youtube.com/watch?vVucsoEhB0NA

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EXIT TICKET

• On a piece of paper answer the following
  questions
• Why do we need transformers?
• How can you determine if it is a step up or step
  down transformer?
• Why do we step up voltage?
• Why do we step down?

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• https//www.youtube.com/watch?vLAtPHANEfQo

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Bird Articles

• https//www.allaboutbirds.org/the-basics-how-why-a
  nd-where-of-bird-migration/
• http//nationalgeographic.org/media/how-do-birds-n
  avigate/
• http//birding.about.com/od/birdbehavior/a/How-Bir
  ds-Migrate.htm
• http//www.independent.co.uk/news/science/revealed
  -secret-of-how-birds-navigate-during-migration-818
  766.html
• http//www.nytimes.com/2012/04/27/science/study-sh
  eds-light-on-how-pigeons-navigate-by-magnetic-fiel
  d.html