Class: Senior Secondary School 1 (SS1, SS 1, SSS1, SSS 1)
Term: First Term
Week: 10
Age: 15 years
Duration: 45 minutes
Subject: Basic Electricity
Curriculum Theme: Basic Electricity
Previous Lesson: Capacitor Color Coding and Values.
Topic: INDUCTORS
Subject Matter: identification of inductors, definition of inductor, circuit symbols of air core inductor, circuit symbols of iron core inductor, uses of inductors, simple construction of an inductor

Specific Objectives

By the end of the lesson, pupils should be able to:

Cognitive Domain:

Define an inductor.
Identify different types of inductors.
State at least three uses of inductors.
Draw the circuit symbols for air-core and iron-core inductors.

Affective Domain:

Show interest in the function and application of inductors.
Appreciate the role of inductors in electronic circuits.

Psychomotor Domain:

Accurately draw the circuit symbols of inductors.
Construct a simple air-core inductor using provided materials.

Collaborate effectively with peers during the construction of a simple inductor.

Reference Materials

The following resources were used in planning this lesson:

9 Years Basic Education Curriculum for Senior Secondary Schools.
State Unified Scheme of Work for Basic Electricity SSS 1.
Basic Electricity for Senior Secondary Schools by A.B. Olajide.

Instructional Materials

The teacher will teach this lesson with the aid of:

Sample inductors (various types).
Insulated copper wire.
Iron core materials (e.g., iron rod, nails).
Non-magnetic core materials (e.g., plastic pen casing, cardboard tube).
Circuit symbol charts for inductors.
Connecting wires and power source for demonstration.

Rationale for the Lesson

This lesson helps pupils understand inductors, which are important components in many electronic circuits. Understanding inductors enables pupils to grasp how devices like radios, televisions, and power supplies work, connecting theory to practical applications in their daily lives.

Prerequisite/Previous Knowledge

Pupils should have basic knowledge of electric current, magnetic fields, and simple circuit components like resistors and capacitors.

Lesson Content/Board Summary

INDUCTORS

Identification of Inductors

Inductors are passive electronic components that store energy in a magnetic field when electric current flows through them. They often appear as coils of wire wound around a core material, which can be air, iron, or ferrite.

Definition of Inductor

An inductor is a passive two-terminal electrical component that stores energy in a magnetic field when electric current flows through it. It opposes changes in the current flowing through it, a property known as inductance.

Circuit Symbols of Inductors

The following are common circuit symbols for inductors:

Air-core inductor: (A series of curved loops, like a spring)
Iron-core inductor: (A series of curved loops with two parallel solid lines drawn above them)

Uses of Inductors

Inductors are used in various electronic applications, including:

Filtering unwanted frequencies in electronic circuits (e.g., in radio tuners and audio crossovers).
Energy storage in switched-mode power supplies and DC-DC converters.
As chokes in power supply circuits to smooth out pulsating DC current.
Part of tuning circuits in radio and television receivers to select specific frequencies.
In transformers, where primary and secondary coils act as coupled inductors.

Simple Construction of an Inductor

A simple inductor can be constructed by winding insulated copper wire around a core material. The core can be non-magnetic (like air or plastic) or magnetic (like an iron rod). The number of turns, the diameter of the coil, and the type of core material determine the inductor’s inductance value.

Teaching Methods/Instructional Techniques

Discussion, Lecture, Demonstration, Question and Answer, Visual Aids

Instructional Procedures

Step 1: Introduction

Time: 5 minutes
Teaching Skill: Set Induction
Teacher’s Activity: The teacher greets the pupils, reviews the previous lesson briefly, and then introduces the new topic by asking pupils if they have seen coiled wires in electronic gadgets. The teacher displays various sample inductors and asks pupils to identify them.
Pupils’ Activity: Pupils respond to greetings, recall previous knowledge, observe the displayed samples, and attempt to identify them.
Learning Point: Pupils are introduced to the topic and begin to identify inductors visually.

Step 2: Identification and Definition of Inductors

Time: 8 minutes
Teaching Skill: Explanation/Demonstration
Teacher’s Activity: The teacher defines an inductor clearly and explains its function as a component that stores energy in a magnetic field. The teacher points out distinguishing features of the displayed inductors.
Pupils’ Activity: Pupils listen attentively, take notes, and ask questions for clarification regarding the definition and identification.
Learning Point: Pupils learn the definition of an inductor and how to identify it.

Step 3: Circuit Symbols of Inductors

Time: 7 minutes
Teaching Skill: Illustration/Demonstration
Teacher’s Activity: The teacher displays charts showing the circuit symbols for air-core and iron-core inductors. The teacher explains the difference between the symbols and demonstrates how to draw them correctly on the board.
Pupils’ Activity: Pupils observe the symbols, practice drawing them in their notebooks, and ask questions about their representation.
Learning Point: Pupils learn and practice drawing the standard circuit symbols for inductors.

Step 4: Uses of Inductors

Time: 5 minutes
Teaching Skill: Explanation/Questioning
Teacher’s Activity: The teacher explains various applications of inductors in electronic circuits, giving simple examples where possible. The teacher encourages pupils to suggest common devices where inductors might be found.
Pupils’ Activity: Pupils listen, take notes, and contribute ideas about where inductors are used.
Learning Point: Pupils understand the practical applications and importance of inductors.

Step 5: Simple Construction of an Inductor (Demonstration)

Time: 7 minutes
Teaching Skill: Demonstration/Practical
Teacher’s Activity: The teacher demonstrates how to construct a simple air-core inductor using insulated copper wire and a non-magnetic core (e.g., a plastic pen casing). The teacher explains that adding an iron core would create an iron-core inductor.
Pupils’ Activity: Pupils observe the demonstration carefully, noting the materials and process involved in constructing a simple inductor.
Learning Point: Pupils observe the practical steps involved in making an inductor.

Step 6: Supervised Construction of an Inductor

Time: 8 minutes
Teaching Skill: Group Work/Supervision
Teacher’s Activity: The teacher divides pupils into small groups and provides them with materials (copper wire, core materials). The teacher supervises as pupils attempt to construct their own simple inductors, offering guidance and assistance.
Pupils’ Activity: Pupils work in groups to construct a simple inductor, applying the knowledge gained from the demonstration.
Learning Point: Pupils develop practical skills in constructing an inductor and work collaboratively.

Step 7: Evaluation/Review

Time: 5 minutes

Teaching Skill: Questioning/Assessment

Teacher’s Activity: The teacher evaluates the learning by asking the following questions:

Define an inductor.
Draw the circuit symbol for an air-core inductor.
Mention two uses of inductors.
Describe how a simple inductor can be constructed.

Pupils’ Activity: Pupils answer orally and in writing.

Learning Point: Pupils demonstrate understanding of the lesson.

Step 8: Conclusion

Time: (Integrated)
Teaching Skill: Summarisation
Teacher’s Activity: The teacher briefly summarises the key points of the lesson, reinforcing the definition, symbols, uses, and construction of inductors. The teacher assigns homework.
Pupils’ Activity: Pupils listen to the summary and copy down the assigned homework.
Learning Point: Pupils consolidate their understanding of the topic.

Lesson Keywords

Inductor – A passive electrical component that stores energy in a magnetic field.
Inductance – The property of an inductor to oppose changes in electric current.
Coil – A length of wire wound in a spiral or helix, forming an inductor.
Air-core inductor – An inductor with a non-magnetic material (like air or plastic) as its core.
Iron-core inductor – An inductor with a magnetic material (like iron) as its core.

Differentiation

For pupils who grasp concepts quickly, the teacher can encourage them to research different types of inductors (e.g., toroid, variable inductors) and their specific applications. For pupils requiring additional support, the teacher can provide more direct guidance during the construction activity and simplify explanations with additional visual aids.

Note for teachers using this lesson plan

Ensure that all materials for the practical construction are readily available and safe for pupils to use. Emphasise safety precautions when handling electrical components, even low voltage ones. Encourage hands-on participation to enhance understanding and engagement.