PURPOSE: To visualize the magnetic field of a bar magnet.

DESCRIPTION: A bar magnet is positioned beneath a plastic box on an overhead projector. Sprinkle iron filings into the box above the magnet and tap the box slightly so that the filings will align along the magnetic field lines.

SUGGESTIONS:

EQUIPMENT: Bar magnet, plastic box and iron filings with overhead projector.

SETUP TIME: 30 min.