5H10.30 - Magnet and Iron Filings

Code Number:
Demo Title:
Magnet and Iron Filings
Magnetic Forces & Fields
Area of Study:
Electricity & Magnetism
Overhead Magnets, Iron filings, Iron Filings in Pop Bottles with Inserted Test Tube, Neodymium Magnets, and Bar Magnet and Horseshoe Magnet Field Line Demonstrations with Pointers.

Video Credit: Jonathan M. Sullivan-Wood

Place the magnets attached to the Plexiglas on the overhead and sprinkle on the iron filings.  Tap the top of the plate to help align the filings.  Observe the magnetic field lines.

3-D magnetic field lines may observed with the pop bottle arrangement.

CAUTION: Do not drop the magnets into the test tube as the bottom will break out.  Slide the magnets gently into the test tube.  These magnets may be removed from the apparatus after demonstration with the use of the small metal rods.

The magnetic field line demonstrations with the pointers allow you to view a 3-D representation of the magnetic field without the mess of the iron filings or ferrofluid.

Magnetic fields may also be viewed using the magnetic viewing film.  This is particularly useful when trying to view the arrangement of flexible magnets or magnets that are not readily accessible.  

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Disclaimer: These demonstrations are provided only for illustrative use by persons affiliated with The University of Iowa and only under the direction of a trained instructor or physicist.  The University of Iowa is not responsible for demonstrations performed by those using their own equipment or who choose to use this reference material for their own purpose.  The demonstrations included here are within the public domain and can be found in materials contained in libraries, bookstores, and through electronic sources.  Performing all or any portion of any of these demonstrations, with or without revisions not depicted here entails inherent risks.  These risks include, without limitation, bodily injury (and possibly death), including risks to health that may be temporary or permanent and that may exacerbate a pre-existing medical condition; and property loss or damage.  Anyone performing any part of these demonstrations, even with revisions, knowingly and voluntarily assumes all risks associated with them.