5G20.55 - Permalloy Rods

Code Number:
Demo Title:
Permalloy Rods
Earth's Magnetic Field
Area of Study:
Electricity & Magnetism
Permalloy Rod and Strips.

When held parallel to the magnetic field (North and South) of the Earth you will be able to pick up strips with the permalloy rod just like a magnet.  When turned 90 degrees to the Earth's magnetic field (East and West) the strips will fall off the rod.  The Mu-Metal shields are also made from permalloy material.  These are used to prevent the penetration by magnetic fields into a detector. In this case these are magnetic shields for photo multiplier tubes.

  • G. D. Freier and F. J. Anderson, "Er-9", A Demonstration Handbook for Physics.
  • Wallace A. Hilton, "E-6a", Physics Demonstration Experiments.
  • George M. Hopkins, "Magnetism", Experimental Science, p. 347.

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