## North by Way of a Magnet

### MAdele CarsonSanta Rosa District Schools

#### Description

During the study of explorers and on magnetism, students will learn about the use of magnets in navigation. They will magnetize needles and make their own compasses.

#### Objectives

The student knows that moving electric charges produce magnetic forces and moving magnets produce electric currents.

#### Materials

Per student:
-Large sewing needles
-Styrofoam plate
-Permanent marker
-Film canister lid
-Magnets

Classroom materials:
-Cardinal direction signs posted
-Water in pitcher
-Wall map of explorer routes
-Masking tape

#### Preparations

1. Gather materials.
2. Assign helpers to pass out plates, magnets, markers, film canister lids, and paper.
3. Have pitcher of water ready.
4. Review the reason for magnets in navigation. (The earth is a giant magnet. Compasses point to magnetic North.)

#### Procedures

1. Review cardinal directions within classroom--which wall of the classroom is north?

2. Have students write N, E, S, and W at the 12, 3, 6, and 9 o'clock points on their plates with the permanent markers.

3. Demonstrate to the students how to magnetize their needles. (Rub the needle point against the magnet repeatedly in the same direction being sure to magnetize only the point of the needle.)

4. Once the needles are magnetized, have the students put the film canister lid, open side up, in the plate and lay the needle in it.

5. Using a pitcher, pour just enough water in the plate to allow the lid to float.

6. If the needle does not turn to the north, it is probably not magnetized enough.

7. Ask the students what will happen if you put the magnet next to the plate at the W, S, or E point. (The needle will move toward the magnet.)

8. What does this mean for using a compass? (You can't be near a strong magnet or metal when using a compass.)

9. Gather magnets. Pour water back into pitcher.

#### Assessments

Students will explain in writing how and why their needle pointed north. When the plates are dry, use a strip of masking tape to tape the needle and film canister lid to the plate. As a follow-up, the students will take home the needle, film lid, and plate and demonstrate their compass to their families.

#### Web Links

Web supplement for North by Way of a Magnet
Adventure Online