5G20.30 - Overhead Magnetic Domain Model
Place the apparatus on the overhead projector. Bring a bar magnetic up to the side or top of the apparatus and note how all of the small magnets line up.
NOTE: Do not touch the bar magnet to the top Plexiglas plate. This will actually re-magnetize the small magnets inside the unit.
The two models have different crystal structure. One is a cubic model and the other is a hexagonal model.
You may also show the domain change by arranging the two coils at the end of the domain model. Apply current and watch the domain line up. Reverse the current and watch the domain reverse its direction.
NOTE: The coils shown are from the Tel Atomic e/m tube demonstration.
- Hector G. Riveros, Julian Betancourt, "Interacting Compasses", TPT, Vol. 47, # 7, Oct. 2009, p. 460.
- David G. Haase, "About Magnetized Needles and Magnetic Field Lines", TPT, Vol. 27, # 5, May 1989, p. 387.
- Es-1, 2: Freier and Anderson, A Demonstration Handbook for Physics.
- Jearl Walker, "5.39, Earth's Magnetic Field and Archaeology", The Flying Circus of Physics Ed. 2, p. 236.
- "350, The Bathtub Vortex", Christopher P. Jargodzki and Franklin Potter, Mad About Physics, p. 137, 276.
- Janice VanCleave, "Magnetic Shake-Up", Physics for Every Kid - 101 Easy Experiments in Motion, Heat, Light, Machines, and Sound, p. 46 - 47.
- Janice VanCleave, "16, Permanent", Magnets, p. 64.
- Ron Hipschman, "Magnetic Lines of Force", Exploratorium Cookbook II, p. 92.1 - 92.2.
- Simon Quellen Field, "More About Magnets", Gonzo Gizmo's, p. 11 - 14.
- Rudolf F. Graf, "Proving the Theory of Magnetism", Safe and Simple Electrical Experiments, p. 53.
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