Magnetism and Magnetic Materials

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Magnetism and Magnetic Materials DTU (10313)
10 ECTS KU 7.5 ECTS
Module 8 25/02/2011 Permanent magnets
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Intended Learning Outcomes (ILO)
(for todays module)

1. Explain how a small piece of graphite can
   levitate
2. Build a magnetic levitation device
3. Construct a dipolar magnet and maximize its
   strength
4. Quantify the lifting force of a magnet
5. Describe the magnetic-to-kinetic energy transfer
   in a simple magnetic gun

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Magnetic levitation

• Think about how to use a set of magnets to
  levitate an object
• Build a magnetic levitation device together with
  your group
• Explain to the class the working principles of
  your levitation device

Dipolar magnets

• Play around with magnetic hard spheres, assemble
  them into various shapes and orderings
  (ferromagnetic and anti-ferromagnetic
  arrangements)
• Measure fields with the hall probe device
• Construct the most powerful magnet you can think
  of by using your set of spheres
• Compete with the other groups and develop the
  largest lifting force (to be measured with a
  digital balance)

A simple magnetic gun

• Look at the demonstration, try it out for
  yourself, and figure out how it works

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Wrapping up

• Dipolar ferromagnets and anti-ferromagnets
• Chains, necklaces, vortices, shapes
• Diamagnetic and ferromagnetic levitation
• The simplest magnetic gun magnetic-to-kinetic
  energy transfer

Next lecture Tuesday March 1, 1315, KU
(A9) Order and broken symmetry (KL)