Physics - Senior Secondary 2 - Magnetic Field

TERM: 3^RD TERM

WEEK: 6

Class: Senior Secondary School 2
Age: 16 years
Duration: 40 minutes for each of 5 periods
Date:
Subject: Physics
Topic: Magnetic Field
Subtopics:

• Magnetic properties of iron and steel
• Magnetic screening or shielding
• Electromagnets and their applications
• Temporary magnets
• The electric bell
• Telephone earpiece, etc.

SPECIFIC OBJECTIVES: By the end of the lesson, students should be able to:

1. Describe the magnetic properties of iron and steel.
2. Explain magnetic screening and shielding.
3. Identify the applications of electromagnets.
4. Understand the concept of temporary magnets and their applications.

INSTRUCTIONAL TECHNIQUES:

• Explanation
• Demonstration
• Questions and answers
• Hands-on activity: Using a compass to investigate the magnetic field around a conductor.

INSTRUCTIONAL MATERIALS:

• Iron and steel objects
• Electromagnets
• Compass
• Physics textbook
• Whiteboard markers
• Videos on electromagnets and applications

INSTRUCTIONAL PROCEDURES

PERIOD 1-5

PRESENTATION

STEP 1: INTRODUCTION

• The teacher introduces the concept of magnetic screening and shielding.
• Students share their understanding of electromagnets and temporary magnets.

STEP 2: EXPLANATION

• Discuss the magnetic properties of iron and steel (iron is easily magnetized, steel retains magnetism).
• Explain magnetic screening or shielding (using materials like iron to block magnetic fields).
• Discuss the concept of electromagnets and their applications (e.g., in electric bells, MRI machines).
• Define temporary magnets and explain their use in devices like electric bells and telephone earpieces.

STEP 3: DEMONSTRATION

• Show how to create an electromagnet using a wire and a nail.
• Discuss how the magnetic field around a conductor carrying current can be detected using a compass.

STEP 4: HANDS-ON ACTIVITY

• Students investigate the magnetic field around a conductor using a compass.

STEP 5: NOTE TAKING

• The teacher writes a summary note on the board that students will copy.

NOTE

• Magnetic Properties of Iron and Steel:
  Iron is easily magnetized but does not retain magnetism, while steel retains magnetism.
• Magnetic Shielding: Blocking magnetic fields using materials like iron.
• Electromagnets: Magnets created by passing current through a wire wound around an iron core.
• Temporary Magnets: Magnets that lose their magnetism once the external field is removed.

EVALUATION

1. What are the magnetic properties of iron and steel?
2. Explain the concept of magnetic shielding.
3. What are electromagnets, and what are their applications?
4. Describe the applications of temporary magnets.

CLASSWORK:

• Create a simple electromagnet and use it to pick up small metallic objects.

CONCLUSION:

• The teacher will review students' answers and provide feedback.

Emphasize the importance of electromagnets and temporary magnets in everyday devices.