Magnetic Fields

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Magnetic Fields

• September 30, 2013
• October 2, 2013

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The Force Between Two Bar Magnets
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Origins of Magnetism
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Magnetic Domains
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Inside Permanent Magnets (and Ferromagnetic
Materials)

• What would happen if you cut the magnet in half
  (between the north and south poles)?

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Magnets Always Have Two Poles
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Magnetic Field of a Bar Magnet
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Thought Questions

• Do you notice anything strange about the
  direction of the field lines? Which way does the
  compass point?
• Draw field lines for the Earths magnetic field.

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Magnetic Field of the Earth
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Magnetic Field Lines Using Iron Filings
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Continuity of Field Lines
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Magnetic Field produced by a Current-Carrying
Wire
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Direction for 3-D in 2-D
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Which way does the current flow?
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Where is the magnetic field strength the greatest?
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The Solenoid
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Effects of Magnetic Fields on Charged Particles
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The Magnetic Force for Positive and Negative
Charges
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The Magnetic Force on a Moving Charged Particle
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What Direction is the Force?
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What are the Different Charges?
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Differences Between Motion in Electric and
Magnetic Fields
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Circular Motion in a Magnetic Field
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Magnetic Force on a Current-Carrying Wire
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The Magnetic Force on a Current-Carrying Wire
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The Magnetic Force Between Current-Carrying Wires
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The Magnetic Force Between Current-Carrying Wires
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Group Discussion

• Walker, Chapter 22 (pp. 742-743)
• Conceptual Questions
• Questions 2-10 and 17-21
• Groups of three
• Concept artist to draw fields
• Recorder to record answer explanation
• Reporter to report findings at the end of class

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Applications of Magnetic Fields

• The Mass Spectrometer
• Velocity Selectors / CRTs
• Magnetic Levity

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Motion in a Magnetic Field
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Helical Motion in a Magnetic Field
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Uranium Separation Using a Mass Spectrometer
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Velocity Selectors
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Cathode Ray Tube
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Magnetic Levity
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Magnetic Trains