# Temperature and Its Standard Units | Conversion between Celsius and Fahrenheit Primary 5 (Basic 5) Term 3 Week 1 Mathematics

### MATHEMATICS

THIRD TERM

WEEK 3

PRIMARY 5

THEME – MENSURATION AND GEOMETRY

PREVIOUS LESSON – Length – Estimation of Length and Its Comparison with Actual Measurement Primary 4 (Basic 4) Term 3 Week 2 Mathematics

### LEARNING AREA

1. Introduction

2. Standard Units of Temperature

3. Conversion between Celsius and Fahrenheit

4. Word Problems

6. Lesson Evaluation and Weekly Assessment (Test)

### LEARNING OBJECTIVES

By the end of the lesson, most pupils should have attained the following objectives –

1. recognize the idea of temperature.

2. identify the mercury thermometer and read the thermometer.

3. identify the clinical thermometer and interpret the reading of human temperature.

4. establish the relationship between degrees Celsius (ºC) and Fahrenheit (ºF).

### ENTRY BEHAVIOUR

The pupils can state the effects dry and rainy seasons.

### INSTRUCTIONAL MATERIALS

The teacher will teach the lesson with the aid of sample or chart showing thermometer.

### METHOD OF TEACHING

Choose a suitable and appropriate methods for the lessons.

Note – Irrespective of choosing methods of teaching, always introduce an activities that will arouse pupil’s interest or lead them to the lessons.

### REFERENCE MATERIALS

1. Scheme of Work

2. 9 – Years Basic Education Curriculum

3. Course Book

4. All Relevant Material

5. Online Information

### LESSON 1 – INTRODUCTION

ACTIVITY 1 – CONCEPTS OF TEMPERATURE

Heat is the cause, a rise in temperature is the effect.

When a substance is hot, the temperature is high and when the substance is less hot (cold), the temperature is lower.

Temperature can be measured with a thermometer in degree Celsius and degree Fahrenheit called unit.

The relationship between the two (2) units can be expressed as unit of one another

Thermometer is an device used to measure temperature of a body or an object.

For example, how hot or cold is water, food, iron, human body, etc.

FEATURES OF A THERMOMETER

The features of thermometer are as follows:

1. Scale – degree Celsius (ºC) and Fahrenheit (ºF)

2. Work liquid

3. Reference point

4. Bulb

UNITS AND SYMBOLS OF TEMPERATURE SCALE

There are two (2) units of measurement for temperature,

1. Degree Celsius (ºC)

2. Degree Fahrenheit (ºF)

THE USES OF THERMOMETER

Thermometers are used to measure temperature.

Below are the uses of thermometer,

1. It is used to measure the outdoor temperature.

2. It is used to measure body temperature – the doctor.

3. It is used to measure body temperature when someone is ill to determine if the person has a fever.

4. It is used to measure the temperature of an experiment.

5. It is used to measure the temperature of a cold room.

QUICK EVALUATION

1. Define thermometer.

2. State the features of thermometer.

3. State the 2 units of measurement for temperature. With appropriate scales.

ASSIGNMENT

Solve the following –

1. Divide 20 by 5, then multiply by 9, then add 32.

2. Divide 50 by 5, then multiply by 9, then add 32.

3. Divide 75 by 5, then multiply by 9, then add 32.

### LESSON 2 – CONVERSION OF CELSIUS TO FAHRENHEIT

Remember the Hint,

To convert Celsius (°C) to Fahrenheit (°F), follow the steps,

• divide the degree by 5
• then multiply by 9,

Working Example 1

Convert 25° Celsius to Fahrenheit.

1st,the 25° by 5,

25° ÷ 5 = 5

2nd, multiply the result by 9,

5 × 9 = 45

45 + 32 = 77° F

Summary, 25° ÷ 5 x 9 + 32 = 77° F

Working Example 2

Convert 30º Celsius to Fahrenheit.

1st,the 30° by 5,

30° ÷ 5 = 6

2nd, multiply the result by 9,

6 × 9 = 54

54 + 32 = 86° F

QUICK EVALUATION

Convert the following to Fahrenheit,

1. 20º

2. 15º

3. 56°

4. 23°

ASSIGNMENT

1. Subtract 32 from 77, then multiply by 5, then divide by 9.

2. Subtract 32 from 86, then multiply by 5, then divide by 9.

### LESSON 3 – CONVERSION OF FAHRENHEIT TO CELSIUS

Remember the Hint – To convert °F to °C, follow the steps,

1st, Subtract 32,

2nd, multiply by 5

3rd, then divide by 9.

Working Example 1

Convert 77º Fahrenheit to degree Celsius.

1st, Subtract 32,

77º — 32 = 45

2nd, multiply by 5

45 x 5 = 225

34rd, then divide by 9.

225 ÷ 9 = 25 ºC

Working Example 2

Convert 86º Fahrenheit to degree Celsius.

1st, Subtract 32,

86º —32 = 54

2nd, multiply by 5

54 x 5 = 270

3rd, then divide by 9.

270 ÷ 9 = 30º C

QUICK EVALUATION

Convert the following to  Celsius,

1. 68º

2. 59º

3. 36

4. 40

LESSON 4 – REVISION

LESSON 5 – WEEKLY ASSESSMENT (TEST)

### PRESENTATION

To deliver the lesson, the teacher adopts the following steps:

1. To introduce the lesson, the teacher revises the previous lesson. Based on this, he/she asks the pupils some questions;

2. Teacher organizes the pupils in groups or pair depending on the size of the class.

3. Teacher displays a sample of thermometer, if available or chart showing digital and analogue thermometer.

4. Teacher lets pupils identify and examine the contents of the chart.

5. Teacher ask pupils to state where is commonly used in their communities.

Pupil’s Activities – Mention the Hospital.

6. Teacher uses chart or sample of the thermometer to introduce the lesson and  explain the meaning of temperature with its standard units.

Pupil’s Activities – Pay attention to the lesson introduction and the meaning of temperature.

7. Teacher guides pupils to identify the features and uses of the thermometer.

Pupil’s Activities – Identify and state the features and uses of the thermometer.

8. Teacher displays a chart showing the relationship between the two units of thermometer.

Pupil’s Activities – Study the chart every well.

9. Teacher guides pupils to identify and state the relationship Celsius and Fahrenheit.

Pupil’s Activities – Identify the relationship Celsius and Fahrenheit.

10. Teacher state the steps to convert Celsius and Fahrenheit to one another and guides pupils to apply the steps.

Pupil’s Activities – Follow the steps to convert the two units to one another.

11. Teacher organizes trip to meteorological or hospital where thermometer is commonly used.

Pupil’s Activities – State the uses of clinical thermometer and other thermometers.

12. Teacher summarizes each of the lesson on the board with appropriate evaluation.

Pupil’s Activities – Participate actively in the summary of the lesson by responding correctly in the questions and write as instructed.

### CONCLUSION

To conclude the lesson for the week, the teacher revises the entire lesson and links it to the following week’s lesson.

### NEXT LESSON

Meaning and Types of Lines, Angles and Bearing Primary 5 (Basic 5) Term 3 Week 2 Mathematics