Magnetic Field Activities
for the High School Classroom

Day 1: Gaining Familiarity	Background Information	Lesson Plan	Student Pages
Day 2: Make Magnetometer	Background Information	Lesson Plan	Student Pages
Day 3: Map Field of 1 Dipole	Background Information	Lesson Plan	Student Pages
Day 4: Subtracting Background Fields to Reveal Desired Field	Background Information	Lesson Plan	Student Pages
Day 5: Interpreting Magnetic Field Maps	Background Information	Lesson Plan	Student Pages
Day 6: Map Field of Current		Lesson Plan	Student Pages
Day 7: Map Field of Room	Background Information	Lesson Plan
Day 8: Strength of Field, Right Hand Rule	Background Information
Day 9: Magnetic Field of Earth
Day 10: Magnetic Field of Sun
Day 11: Introduction to Plasma	Background Information
Day 12: Plasma/Magnetic Field Interactions	Background Information
Day 13: Sun-Earth Plasma Interactions

Teacher Overview

The following unit is designed to acquaint the student with the magnetic field. The assumed average student has some familiarity with the uniform gravitational field of classical Newtonian dynamics and kinematics lessons. This is not required however. The unit is meant to introduce the idea of a field through investigations of magnetic fields as produced by various common magnetic materials and direct currents. The difference between a magnetic field and a gravitational field is that a gravitational field, in the experience of a student, always points downward and is always of the same strength (9.8 m/s2). Magnetic fields are not limited to one direction or strength, in the student's experience. That is, all students are assumed to have noticed that some magnets are stronger than others. Further, all students will know, by the mid-point of this unit, that magnetic fields are inherently loop shaped. One important similarity does exist between the magnetic field of the earth and the gravitational field of the earth: both are mysteriously produced by the same object. Thus, these two fields are easily confused in the mind of the student, and are subject to 'common sense' interpretations that may be at odds with scientific explanation. The 'common sense' interpretations can be hard to modify. Indeed, students are likely to speak as if all magnetic interactions are attractive (e.g., 'the magnetic personality') even though they also know from experience that it is hard to force opposite poles of different magnets together.

In general terms, the student will gain an appreciation for the vector nature of fields, the ubiquity of field sources in the environment, and the ability to visualize such fields as 3-dimensional entities.

Specific Learning Outcomes:

• The student will learn that a magnetic field is a real entity with real effects.
• The student will learn that moving charges or currents are needed to produce and detect a magnetic field.
• The student will be able to explain the root cause of the apparently "permanent magnetism" of materials such as iron, cobalt, and nickel.
• The student will learn to construct a vector field description of how a magnet affects the space around it.
• The student will be able to construct a field diagram based on a series of discrete measurements.
• The student will design and construct an apparatus which allows the detection of magnetic field direction at the location of the instrument.
• The student will design, execute, interpret and report on a series of experiments leading to a coherent qualitative understanding of magnetic fields.
• The student will understand the direction and magnitude content of vector representations.
• The teacher will use a Socratic approach and guided learning methods.

Project Ideas:

• Magnetoreceptors in animals
• Magnetism and bacteria
• Magnetism and newts
• Overview of animals and magnetism, especially migration
• Lobsters, turtles, and mollusks
• Rainbow trout:
  Walker, Michael M., Carol E. Diebel, Cordula V. Haugh, Patricia M. Pankhurst, and John C. Montgomery, 1997.
  "Structure and function of the vertebrate magnetic sense," Nature 390, 371.
  This article describes how rainbow trout can sense and respond to magnetic fields. It tells where in the nose the trouts' magnetoreceptors are located and how they are connected to the brain. Perhaps this sensory system enables trout to navigate over long distances using Earth's magnetic field for orientation. (See also Walker's homepage.)
• Another magnetometer recipe
• Variations in magnetic field of the earth:
  http://www.sciam.com/1999/0199issue/0199amsci.html
  http://www.sciam.com/2000/0300issue/0300amsci.html
• Magnetizing Objects:
  http://k12.magnet.fsu.edu/maglabalpha/html/movies/nail.mov
  http://k12.magnet.fsu.edu/maglabalpha/html/movies/nail2.mov
  http://k12.magnet.fsu.edu/maglabalpha/html/library/magdemag.html

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Lesson Development/Writing: Ed Eckel and Matthew Friel
Web Design: Theresa Valentine
Last Updated: 8/25/2000