Notes

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SPI 080712.3 Magnetic Fields
Notes
Science
Tennessee SPI Objective Distinguish among the
Earths magnetic field and the fields that
surround a (permanent) magnet and an
electromagnet.
Instructions 1) First click on "View" from the
top-menu bar. 2) Then click on "Slide Show" from
the drop-down menu. 3) Then use the right-arrow
button on your keyboard to advance through this
presentation.
Check for Understanding Create a chart to
distinguish among the earths magnetic field and
the fields that surround a (permanent) magnet and
an electromagnet.
Essential Question(s) What is a magnetic field?
What are the similarities and differences between
the Earths magnetic field and the fields from
permanent magnets electromagnets?
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SPI 080712.3 Magnetic Fields
Notes
Science
Magnetic Fields

• An invisible magnetic field exists around all
  magnets.

See Holt Online Ch. 16 Sect 1 Visual Concept
Title Magnetic Fields
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SPI 080712.3 Magnetic Fields
Notes
Science
Magnetic Fields

• You can see the magnetic field lines by using
  fine iron filings.

Note - the field lines are concentrated at the
ends (called poles)
South Pole
North Pole
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SPI 080712.2 Electromagnets
Notes
Science
F.Y.I Why Are Some Substances Magnetic?

• All atoms have magnetic fields with north and
  south poles

• Atoms in objects are found in areas called
  domains.

• If the north and south poles in a domain line up,
  this makes the object magnetic.

If they dont line up, the object is not magnetic.
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SPI 080712.3 Magnetic Fields
Notes
Science

• Magnetic Poles North and South
• areas on a magnet that have opposite magnetic
  qualities.
• One area is called the north pole.
• The opposite area is called the south pole.
• F.Y.I.-the field lines start at the north pole
  end at the south pole
• See Holt Online Ch. 16 Sect 1 Visual Concept
• Title Magnetic Poles

South Pole
North Pole
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SPI 080712.3 Magnetic Fields
Notes
Science

• North and South Poles
• All magnets have these poles regardless of their
  shape

• Also, if you cut a magnet in half, each half will
  still have these two poles (north and south)

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SPI 080712.3 Magnetic Fields
Notes
Science

• Magnetic Forces
• magnets exert force on other magnets

• Opposites attract

(North South pull towards each other)
(North North or South South push away)

• Like repels

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SPI 080712.3 Magnetic Fields
Earth is a Giant Magnet
Notes
Science

• Earth has a powerful magnetic field called the
  geomagnetic field

See Holt Online Ch. 16 Sect 1 Visual
Concept Title "Earth's Magnetic Field"
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SPI 080712.3 Magnetic Fields
Notes
Science

• Now for the confusing part
• Earth's north magnetic pole is at the southern
  end (Antarctica)
• Earth's south magnetic pole is at the northern
  end (Arctic Circle)

Geographic North
Magnetic North
Magnetic South
Geographic South
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SPI 080712.3 Magnetic Fields
Notes
Science
Magnetic South Pole
Magnetic North Pole
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SPI 080712.3 Magnetic Fields
Notes
Science
Another name for Earth's magnetic field is the
magnetosphere.
The magnetosphere protects us from harmful solar
radiation
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We can see the solar wind hitting Earth's
magnetosphere. In the northern hemisphere this is
called the Aurora Borealis. In the southern
hemisphere this is called the Aurora Australis
SPI 080712.3 Magnetic Fields
Notes
Science
View this video Title "Dance of the
Spirits-Northern Lights Link Northern Ligths
Video Clip
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SPI 080712.3 Magnetic Fields
Science
Questions
Here is an example of a question you might see on
a quiz or test.
14
SPI 080712.3 Magnetic Fields
Science
Questions
Here is an example of a question you might see on
a quiz or test.
15
SPI 080712.3 Magnetic Fields
Science
Questions
Here is an example of a question you might see on
a quiz or test.
16
SPI 080712.3 Magnetic Fields
Science
Questions
Here is an example of a question you might see on
a quiz or test.
17
SPI 080712.3 Magnetic Fields
Science
Questions
Here is an example of a question you might see on
a quiz or test.