Demonstrative Projects With Magnets
- Magnet at workcrane image by Matthew Cole from Fotolia.com
Magnets produce a magnetic field that is not visible other than how it reacts with other ferromagnetic materials. All magnets have a north and south pole, and this polar nature is what causes some to be pulled together, and others to be repelled. This interaction provides a lot of visual interest for demonstrations. - Steel nails can become magnetized if they are hammered on with the nail in line with the poles of the earth. To perform this project, bring a compass near the nail and see if there is any effect. There shouldn't be. Then lay the nail on a two-by-four piece of wood and hit the nail 50 times each with it lined up north to south, south to north, and east to west. Bring the compass near it after each direction. With north to south, it will become magnetized, with south to north it will becomes magnetized in the opposite direction, and with east to west, it will no longer be magnetized.
- Creating a compass is one of the best demonstrations of magnets and the Earth's magnetic field. Gather a glass bowl half-full of water, a pin, a magnet and a cork. Holding the pin in one hand and the magnet in the other, rub the magnet on the pin from one end to the other--always in the same direction, not back and forth--a minimum of 20 times. Push the pin through the cork and float in the bowl of water. The pin will rotate so that it's lined up along the Earth's north-south axis.
- Iron filings illustrate the magnetic field. Gather up a magnet, extra fine steel wool, plastic bottle of baby oil with one paper label, and some scissors. Use the scissors to cut the steel wool in strips to give you tiny pieces of iron filings. You want a lot of them to provide a much better visual. Dump the filings into the bottle of baby oil and shake it up using a circular motion. When the filings are well mixed, hold the magnet about half an inch to an inch from one side of the bottle and watch the filings move to show the magnetic field.
