Magnetism (JSS 3- Basic Science Lesson Note: Second Term, Week Eight)

Week 8

Subject: Basic Science
Class: JSS 3
Week of the Second Term: 8th Week
Topic: Magnetism
Sub-Topic: Care of Magnets.

---

Instructional Objectives

At the end of the lesson, students should be able to:

1. Explain the importance of caring for magnets to maintain their strength.
2. Identify methods for properly storing and handling magnets.
3. Recognize common mistakes that can demagnetize a magnet.

---

Entry Behaviour

Students should already have a basic understanding of magnets and their properties from previous lessons.

---

Instructional Materials

1. Basic Science textbook
2. Examples of magnets in various conditions (e.g., new, old, demagnetized)
3. Visual aids depicting proper magnet care practices

---

Reference Materials

• Adeosun, A., Nwabuidike, E., & Odebiyi, B. (2017). Basic Science for Junior Secondary School 3 Textbook (BEC Edition). Lagos: Spectrum Books Limited.
• Bajah, S.T., et al. (2017). Basic Science for Junior Secondary School 3 Textbook (BEC Edition). Lagos: University Press PLC.

---

Content

Importance of Proper Care

Proper care of magnets is essential for several reasons:

1. Longevity: Taking care of magnets can significantly extend their lifespan, allowing them to maintain their strength and usefulness over time.
2. Performance: Well-maintained magnets perform better, providing reliable magnetic force when used in applications such as motors, generators, and magnetic compasses.
3. Safety: Improperly handled magnets can pose safety risks, especially strong magnets that can pinch skin or cause injury if they snap together unexpectedly.

Best Practices for Caring for Magnets

1. Avoid Heat:
   • What to Do: Keep magnets away from heat sources, such as stoves, radiators, and direct sunlight. High temperatures can demagnetize magnets or reduce their magnetic strength.
   • Why It Matters: Most magnets lose their magnetism when heated above their Curie temperature (the temperature at which a magnet loses its permanent magnetic properties).
2. Prevent Physical Damage:
   • What to Do: Handle magnets gently and avoid dropping them or subjecting them to sudden impacts.
   • Why It Matters: Physical shock can disrupt the alignment of the magnetic domains within the magnet, weakening its magnetic field.
3. Store Properly:
   • What to Do: Store magnets in a cool, dry place, preferably in a protective case or container to prevent dust accumulation and accidental impacts.
   • Why It Matters: Proper storage prevents physical damage and environmental factors that could affect the magnet’s strength.
4. Keep Magnets Separated:
   • What to Do: When storing multiple magnets, keep them separated using spacers or non-magnetic materials to prevent them from sticking together.
   • Why It Matters: When magnets are allowed to stick together, they can become damaged or demagnetized when pulled apart.
5. Use Magnetic Keepers:
   • What to Do: For strong magnets, use magnetic keepers (pieces of soft iron) to preserve their magnetic field when not in use.
   • Why It Matters: Keepers help maintain the alignment of the magnetic domains and prevent the magnet from losing its strength.
6. Clean Regularly:
   • What to Do: Clean magnets with a soft cloth to remove dust and debris. Avoid using harsh chemicals that could corrode the surface.
   • Why It Matters: Regular cleaning ensures optimal performance and prevents any buildup that might interfere with the magnet’s function.

Step 1: Introduction

Lesson Presentation (Step-by-Step Procedure)

Others removed.