TERM – 3^RD TERM

WEEK NINE

Class: Junior Secondary School 1

Age: 12 years

Duration: 40 minutes of 5 periods each

Date:

Subject: BASIC TECHNOLOGY

Topic: BASIC ELECTRICITY 3

SPECIFIC OBJECTIVES: At the end of the lesson, pupils should be able to

State ohm's law
Describe the relationship between current, Voltage and resistance.
Carry simple calculations of basic electricity.

INSTRUCTIONAL TECHNIQUES: Identification, explanation, questions and answers,

demonstration, videos from source

INSTRUCTIONAL MATERIALS: Videos, loud speaker, textbook, pictures,

INSTRUCTIONAL PROCEDURES

PERIOD 1-2

PRESENTATION

TEACHER’S ACTIVITY

STUDENT’S

ACTIVITY

STEP 1

INTRODUCTION

The teacher Identify the most important concept involving electrical calculations (current, resistance, voltage, power and charge)

Students pay

attention

STEP 2

EXPLANATION

Teacher discuss ohms laws and describe the relationship between current, Voltage and resistance.

Students pay

attention and

participate

STEP 3

DEMONSTRATION

Teacher guide students to carry out basic calculations of electricity

Students pay

attention and

participate

STEP 4

NOTE TAKING

The teacher writes a summarized

note on the board

The students

copy the note in

their books

NOTE

BASIC ELECTRICITY 3

Basic electrical calculations often involve concepts like:

Ohm's Law: Ohm's Law is a fundamental principle in electrical engineering and physics, expressing the relationship between voltage (V), current (I), and resistance (R) in an electrical circuit. It is represented by the equation:

V = I x R

Where:

- V is the voltage across the circuit,

- I is the current flowing through the circuit,

- R is the resistance in the circuit.

This equation helps in understanding how these three parameters are interrelated. It can also be used in terms of current and resistance.

That is; Current (I) = Voltage (V).

Resistance(R) = V/R

Current is measured in amperes

And Resistance(R) = Voltage (V)

Current(I). =V/I

Resistance is measured in ohms

Power(P): It is the rate at which energy is transferred or the rate at which work is done in an electrical circuit. The relationship between power, voltage (V), and current (I) is expressed by the following equations:

I. (P = V x I): This is the general power formula, where P is power, V is voltage, and I is current.

II. (P = I² x R ): This formula is applicable when you know the current and resistance in a circuit.

Power is measured in watts (W).

Charge refers to the property of matter that gives rise to electric force. It is an inherent property of certain subatomic particles, specifically electrons and protons.. The unit of electrical charge is the coulomb (C). It is represented by the equation

Q = C x V

Where Q is the charge

C is the capacitance

V is the voltage.

Example 1: Calculate the charge across the capacitor 5mF and the voltage applied is 25 V.

Solution

Capacitance(C) = 5 mF,

Voltage applied V = 25 V,

The Charge across the capacitor is given by Q = CV

= 5 mF x 25 V = 125 x 10^² C

= 0.125 C.

Example 2: A wire carrying a current of 4 Amperes is having a resistance of 5. Calculate the potential difference across its ends.

Solution:

Current I = 4 A,

Resistance R = 5 ohm

Formula for calculating Potential difference is V = IR

= 4 x 5 = 20 v.

Example 3: Calculate the amount of current that flows in the circuit below:

Solution

Voltage (V) = 9v

Resistance (R) = 10 ohms

Current (I) = V/R

= 9/10 = 0.9 ampere

EVALUATION: 1. State ohm's law.

Describe the relationship between current, Voltage and resistance.

CLASSWORK: As in evaluation

CONCLUSION: The teacher commends the students positively

Lesson Notes By Weeks and Term - Junior Secondary 1