Applications Activity: Giant Magnetoresistance
| View full, printable version of this activity |
Audience: Middle school class
Time Needed: 45 minutes
Objectives:
- Be introduced to nanotechnology and GMR, a phenomenon based on nanotechnology
- Review basic concepts of electricity and magnetism
- Participate in an interactive, hands-on activity that relates current computer technology to their lives.
Activity Materials:
- Slides or overhead transparencies (pdf)
- Hard drives
- Screwdrivers (Philips and Torx)
- Poster paper
- Tape Markers
- Simple circuit demo (metal scraps, pieces of other materials, batteries, battery snaps, wire, LEDs)
- Magnetism demo (cow magnets, metal scraps, pieces of other materials)
- Coil LED demo (cow magnets, tube (rolled-up transparency) with copper coil attached to LED)
- Worksheets
Activity Description:
Students dissect a hard drive to explore the fundamental principles of electricity, magnetism, and a nanotechnology-based phenomenon called giant magnetoresistance (GMR). GMR is exhibited by materials that have alternating layers of magnetic and non-magnetic materials, each a few atoms thick. The resistance of these materials changes dramatically when a magnetic field is introduced. GMR materials can be found in the read heads of computer hard drives. Students participate in a treasure hunt to find different components of the hard drive in order to win a prize. Students explore magnetism and electricity through hands-on demonstrations and must answer questions about these topics in order to receive visual clues to aid in their hard drive treasure hunt.
Supplemental Materials:
- Slides: Giant Magnetoresistance (GMR) and the Modern Hard Drive (pdf)
- Movie: Giant Magnetoresistance
- Background Information: Giant Magnetoresistance
