Bell Work 2/18/16

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Bell Work 2/18/16
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Bell Work 2/18/16
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White Board Word Splash
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• How are magnets related to your everyday life?
• What is the relationship between magnets and
  electronics (devices).
• Describe things that are attracted to magnets?
  Predict what would happen if you dipped a bar
  magnet into a box of paper clips?
• Predict ways magnets could change the way we
  travel from place to place.

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Cool Stuff
Video
Cling Climb
Maglev Train 2000mph
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HYPERLOOP
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Student Objectives

• SPI 0807.12.1 Recognize that electricity can be
  produced using a magnet and wire coil
• SPI 0807.12.2 Describe the basic principles of an
  electromagnet
• SPI 0807.12.3 Distinguish among the Earths
  magnetic field, a magnet, and the fields that
  surround a magnet and an electromagnet
• TOC Magnets

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Magnetic Poles are points on a magnet that have
opposite magnetic qualities. The pole of a magnet
that points to the north is called the magnets
north pole. The opposite end of the magnet,
called the south pole, points to the south.
Video

• When you bring two magnets close together, the
  magnets each exert a magnetic force on the other.
  These magnetic forces result from spinning
  electric charges in the magnets. The force can
  either push the magnets apart of pull them
  together.

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• If you hold the north poles of two magnets close
  together, the magnetic force will push the
  magnets part. The same is true if you hold the
  south poles close together.
• If you hold the north pole of one magnet close to
  the south pole of another magnet, the magnetic
  force will pull the magnets together.
• A magnetic field exists in the region around a
  magnet in which magnetic forces can act.

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• Why are some materials magnetic and some not?
• In materials such as iron, nickel, and cobalt,
  groups of atoms are in tiny areas called domains.
  The north and south poles of the atoms in a
  domain line up and make a strong magnetic field.
• If the domains in an object are randomly
  arranged, the magnetic fields of the individual
  domains cancel each other out, and the object has
  no magnetic properties.

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• If most of the domains in the object are aligned,
  the magnetic fields of the individual domains
  combine to make the whole object magnetic.
• Losing Alignment - When domains move, the magnet
  is demagnetized, or loses its magnetic
  properties.
• Making Magnets - You can make a magnet from
  demagnetized material if you line up its domains
  with another magnet.
• When you cut a magnet in half, you end up with
  two magnets.

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• Name four kinds of magnets
• Some magnets, called ferromagnets, are made of
  iron, nickel, cobalt, or mixtures of those
  metals.
• Another kind of magnet is the electromagnet. This
  is a magnet made by an electric current.
• Temporary magnets are made from materials that
  are easy to magnetize. But they tend to lose
  their magnetization easily.
• Permanent magnets are difficult to magnetize, but
  tend to keep their magnetic properties longer.

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• Name two examples of the effect of Earths
  magnetic field.
• The Earth behaves as if it has a bar magnet
  running through its center.
• The point of a compass needle is attracted to the
  south pole of a magnet. Opposite poles of magnets
  attract each other.
• A compass needle points north because the
  magnetic pole of Earth that is closest to the
  geographic North Pole is a magnetic south pole.
• Scientists think that the Earths magnetic field
  is made by the movement of electric charges in
  the Earths core.
• Earths magnetic field plays a part in making
  auroras. An aurora is formed when charged
  particles from the sun hit oxygen and nitrogen
  atoms in the air.

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Facts About Electricity

• Electric currents produce a magnetic field
• The direction of the field depends on the
  direction of the current
• It is a force caused by electric charge
• The two positive charges repel each other, as do
  the negatives
• Travels at the speed of light (186,000 mph)

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• Section 2
• Electromagnetismthe interaction between
  electricity and magnetism.
• Solenoids and electromagnets.
• A solenoid is a coil of wire that produces a
  magnetic field when carrying an electric current.
• An electromagnet is made up of a solenoid wrapped
  around an iron core.
• Electromagnets are very useful because they can
  be turned on and off as needed. The solenoid has
  a field only when there is electric current in
  it.

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Group ActivityMove Around The Room
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Independent Work

• Complete Venn Diagram on Magnetism and
  Electricity

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Exit Ticket
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Exit Ticket
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• Section 3
• Michael Faraday conducted an experiment trying to
  get the magnetic field of the electromagnet to
  make an electric current in a second wire.
• Faraday realized that electric current in the
  second wire was made only when the magnetic field
  was changing. The process by which an electric
  current is made by changing a magnetic field is
  called electromagnetic induction.
• The electric current produced by the generator
  changes direction each time the coil makes a half
  turn. Because the electric current changes
  direction, it is an alternating current.

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• The energy that generators convert into
  electrical energy comes from different sources
  such as fossil fuels and nuclear energy.
• A transformer increases or decreases the voltage
  of alternating current.
• The number of loops in the primary and secondary
  coils of a transformer determines whether it
  increases or decreases the voltage.
• The electric current that brings electrical
  energy to your home is usually transformed three
  times.