Magnetic Fields and Permanent Magnets

Active learning works for this topic because students need to see magnetic fields with their own eyes to move beyond abstract ideas. When students handle magnets and iron filings, they build mental models that static images cannot provide. This hands-on work makes invisible forces visible and memorable.

• 5th Year
• Principles of the Physical World: Senior Cycle Physics
• 4 activities
• 15 min–45 min

Learning Objectives

1. Compare the magnetic field patterns generated by bar magnets and horseshoe magnets, identifying similarities and differences in pole concentration.
2. Explain the principle by which a compass needle aligns with the Earth's magnetic field to indicate direction.
3. Predict the resultant force (attraction or repulsion) between two permanent magnets based on the orientation of their poles.
4. Analyze the interaction between a permanent magnet and magnetic materials, classifying materials as ferromagnetic, paramagnetic, or diamagnetic.

Stations Rotation

⏱ 45 min·Small Groups

Stations Rotation: Magnet Field Stations

Prepare four stations: one with bar magnets and iron filings, one with horseshoe magnets, one for compass tracing around magnets, and one for pole interaction predictions. Groups rotate every 10 minutes, sketching field lines and noting observations. Conclude with a class share-out of comparisons.

Prepare & details

Explain how a compass works using the Earth's magnetic field.

Facilitation Tip: During the Magnet Field Stations activity, remind students to use only small amounts of iron filings to avoid cluttered patterns that obscure field lines.

Setup: Tables/desks arranged in 4-6 distinct stations around room

Materials: Station instruction cards, Different materials per station, Rotation timer

• Remember
• Understand
• Apply
• Analyze
• Self-Management
• Relationship Skills

Experiential Learning

⏱ 25 min·Pairs

Pairs Prediction: Pole Interactions

Pairs label north and south poles on two bar magnets, predict attraction or repulsion for all combinations on a worksheet, then test with real magnets. They record results and explain using like-unlike pole rules. Extend by trying with multiple magnets.

Prepare & details

Compare the magnetic field lines around a bar magnet to those around a horseshoe magnet.

Facilitation Tip: For the Pole Interactions activity, provide labeled magnets and ask pairs to test all combinations before sharing results, ensuring they see the complete pattern.

Setup: Varies; may include outdoor space, lab, or community setting

Materials: Experience setup materials, Reflection journal with prompts, Observation worksheet, Connection-to-content framework

• Apply
• Analyze
• Evaluate
• Self-Awareness
• Self-Management
• Social Awareness

Experiential Learning

⏱ 30 min·Whole Class

Whole Class: Compass Earth Field Walk

Distribute compasses; students walk school grounds noting needle directions relative to geographic north. Mark magnetic north on a large map. Discuss how Earth's field causes alignment and link to permanent magnet fields.

Prepare & details

Predict the interaction between two permanent magnets based on their poles.

Facilitation Tip: During the Compass Earth Field Walk, bring a map and have students mark their starting point to compare compass direction with true north.

Setup: Varies; may include outdoor space, lab, or community setting

Materials: Experience setup materials, Reflection journal with prompts, Observation worksheet, Connection-to-content framework

• Apply
• Analyze
• Evaluate
• Self-Awareness
• Self-Management
• Social Awareness

Experiential Learning

⏱ 15 min·Individual

Individual: Field Line Sketches

Provide images of iron filings around magnets; students sketch field lines, label poles, and compare bar to horseshoe patterns. Follow with self-check against model diagrams.

Prepare & details

Explain how a compass works using the Earth's magnetic field.

Facilitation Tip: After Field Line Sketches, ask students to label regions of high and low field density and explain how this relates to force strength.

Setup: Varies; may include outdoor space, lab, or community setting

Materials: Experience setup materials, Reflection journal with prompts, Observation worksheet, Connection-to-content framework

• Apply
• Analyze
• Evaluate
• Self-Awareness
• Self-Management
• Social Awareness

Teaching This Topic

Teaching this topic works best when students experience the phenomena first and then formalize their observations with vocabulary and rules. Avoid starting with definitions; instead, let students observe patterns and then introduce terms like 'field lines' and 'poles' to match what they see. Research shows that tactile experiences with magnets lead to stronger conceptual understanding than lectures alone.

What to Expect

Successful learning looks like students confidently predicting and explaining magnetic interactions using evidence from their investigations. They should describe how field line density and compass directions relate to force strength and direction. By the end, students should use correct terminology and apply rules to new scenarios.

Watch Out for These Misconceptions

Common Misconception

During the Pole Interactions activity, watch for students who assume a single pole exists or ignore the second pole when predicting force directions.

What to Teach Instead

Ask students to test all four combinations of poles (N-N, N-S, S-N, S-S) and record their observations in a table to see the consistent pattern of like-repel and unlike-attract.

Common Misconception

During the Magnet Field Stations activity, watch for students who describe field lines as physical ropes or wires.

What to Teach Instead

Have students trace field lines with a compass and note that the needle moves smoothly along curves, not along rigid paths; ask them to sketch what they observe to reinforce the idea of continuous curves.

Common Misconception

During the Compass Earth Field Walk activity, watch for students who believe a compass points exactly to the geographic North Pole.

What to Teach Instead

Provide maps with magnetic declination marked and ask students to measure the difference between their compass reading and true north; have them average group measurements to demonstrate variability.

Assessment Ideas

Exit Ticket

After the Pole Interactions activity, provide diagrams of two magnets facing each other and ask students to draw arrows showing force direction and write one sentence explaining their prediction using evidence from their testing.

Quick Check

During the Magnet Field Stations activity, hold up a bar magnet near a compass and ask students to observe the needle's movement; then ask them to explain how this shows the Earth's magnetic field interacting with the magnet.

Discussion Prompt

After the Field Line Sketches activity, present the scenario: 'Two bar magnets are placed with like poles facing each other. How would you orient a third magnet to levitate an iron object between them?' Facilitate a class discussion on their proposed solutions, focusing on field line density and force balance.

Extensions & Scaffolding

• Challenge students to design a horseshoe magnet arrangement that creates a uniform field in the center by testing and refining their setup.
• For students who struggle, provide pre-labeled diagrams of field lines around bar and horseshoe magnets to help them connect observations to visuals.
• Deeper exploration: Have students research and compare how MRI machines use magnetic fields, connecting their classroom learning to real-world applications.

Key Vocabulary

Magnetic Field	A region around a magnetic material or a moving electric charge within which the force of magnetism acts.
Magnetic Pole	Either of the two points on a magnet, or a magnetic field, that are the sources of magnetic field lines; typically designated North and South.
Magnetic Field Lines	Imaginary lines used to represent the direction and strength of a magnetic field, showing the path a north magnetic pole would take.
Ferromagnetic Material	A material, such as iron, that is strongly attracted to magnets and can be magnetized itself.