Magnetic Attraction
Students complete a series of six short investigations involving magnets to learn more about their properties. Students also discuss engineering uses for magnets and brainstorm examples of magnets in use in their everyday lives.
Figure 1. Pattern of iron filings caused by a bar magnet.
While engineers use magnets many purposes, one important use is information storage, or "magnetic memory." We see this everyday in credit cards, VCRs, cassette tapes, computers and zip disks. Magnets are also used in motors and acoustics. Engineers apply their understanding of magnetic fields to design satellites that withstand the effects of the earth's strong magnetic field, which can affect a satellite's orientation around the planet and disrupt sensitive electronics. Engineers design magnetic resonance imaging (MRI) techniques to create computerized images of internal human body tissues using the nuclear magnetic resonance of atoms in the body with the application of radio waves.
After this activity, students should be able to:
- Describe some basic properties of magnets.
- Explain that magnets have two different poles that attract or repel other magnets or objects.
- List several devices that engineers have designed using magnets.
- List everyday devices that use magnets.