A Circuit that Magnetizes a Nail.

Students work together to make the magnet work.

Materials

  • Two or more AA or C size batteries

  • 4 feet of bell wire, or thin wire with plastic insulation (16 to 20 gauge) sold at your hardware store. Wire with plastic insulation will work.

  • Cutters for the wire

  • A large nail

  • A book to align and hold the batteries

  • Iron filings, paper clips or any other small light magnetic items ( Optional - Iron filings can be found at your local teacher supply store.

Procedure

Before the lesson prepare the nail. Find the middle of the wire and coil it around the nail as tightly as you can until there is just a foot left on each end. Tie the wire to the nail to keep it tightly coiled. Show the students the materials and how the battery works. Begin with two batteries. Align the batteries in the center of a large open book. The batteries are laid with the positive end to the negative end of the next. Have three students cooperate together to raise iron filings or paper clips. The first and second keep the batteries in place and each keeps a different wire end in contact with the opposing battery terminals. The third student picks up items with the nail. Emphasize that everything in the circuit has to be touching. Count the number of paper clips raised by the power of two batteries.

Now put three batteries in the book and ask the students to predict if three will pick up more than two. Then ask the students to tell why four batteries will pick up more than three. You can demonstrate four batteries but do not let the children experiment with more than three batteries.

To conclude

Ask the students to describe what must happen for the magnet to work. How do we work together to gain what we want? Model on the chalkboard or overhead how to write down the students' verbal answers.

In Centers

The third student can call "on" and "off" to pick up iron filings or paper clips and dump them into another pile. The three students take turns. Students must take one of three roles to make the battery work. One student should always count to 10 slowly and say "stop" to prevent any minor burns. The first and second keep the batteries in place and each keeps a different wire end in contact with the battery. The third student picks up items with the nail.