# Meaning and Effects of Frictional Force | Advantages and Disadvantages of Fractional Force | Methods of Reducing Frictional Force Primary 6 (Basic 6) Term 3 Week 6 Basic Science

### BASIC SCIENCE

BASIC SCIENCE AND TECHNOLOGY

SMASE – ASEI PDSI METHOD

THIRD TERM

WEEK 6

PRIMARY 6

THEME – LEARNING ABOUT OUR ENVIRONMENT

PREVIOUS LESSON – Meaning, Types and Effects of Force (Primary 6)

### LEARNING AREA

1. Introduction

2. Meaning of Frictional Force

3. Effects of Frictional Force

5. Methods of Preventing Frictional Force

6. Lesson Evaluation and Weekly Assessment (Test)

### LEARNING OBJECTIVES

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

1. explain frictional force as the resistance between two surfaces in contact.

2. mention instances of the application of frictional force in daily activities.

4. discuss ways of preventing frictional force.

### ENTRY BEHAVIOR

The pupils can state the uses of lubricant and grease.

### INSTRUCTIONAL MATERIALS

The teacher will teach the lesson with the aid of palms. Stones and pebbles, balls bearings, matched, knife, floor, water, Vaseline, sand paper, glass, oil, soapy water.

### 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

Meaning and Effects of Frictional Forces – ASEI PDSI METHOD (Primary 6)

Third Term Scheme of Work and Plan Lesson Note for Basic Science and Technology Primary 4, Primary 5 and Primary 6 Links

CONTENT OF THE LESSON

LESSON ONE – INTRODUCTION

To stop a moving object, a force must act in the opposite direction to the direction of motion.

For instance, if you push your book across your desk, the book will move. The force of the push moves the book.

As the book slides across the desk, it slows down and stops moving.

The force that opposes the motion of an object is called friction.

MEANING OF FRICTION

Friction is the force that opposes the motion of an object.

Friction can slow down or stops any moving objects.

Friction plays a vital role in our daily life.

Without friction we are handicap.

EFFECTS OF FRICTIONAL FORCE

The effects of the frictional force on objects are as follows:

1. It opposes the motion of all objects.

2. It slow down any moving objects.

3. It counteracts the acceleration of an object.

4. It prevents surfaces from sliding against each other.

5. It causes objects to accelerate.

The advantages of friction are as follows:

1. It prevents slipping while walking.

2. It stops cars from moving.

3. We cannot fix nail in the wood or wall if there is no friction.

It is friction which holds the nail.

4. A horse cannot pull a cart unless friction furnishes him a secure Foothold.

Despite the fact that the friction is very important in our daily life, it also has some disadvantages such as,

1. The main disadvantage of friction is that it produces heat in various parts of machines.

In this way some useful energy is wasted as heat energy.

2. Due to Friction, we have to exert more power in machines.

3. It opposes the motion.

4. Due to friction, noise is also produced in machines.

5. Due to friction, engines of automobiles consume more fuel which is a money loss.

### LESSON 3 – METHODS OF REDUCING FRICTION

There are a number of methods to reduce Friction,

1. The use of lubricants

2. The use of grease

3. The use of ball

4. The design modification

1. THE USE OF LUBRICANTS

The parts of machines which are moving over one another must be properly lubricated by using oils and lubricants of suitable viscosity.

2. THE USE OF GREASE

Proper greasing between the sliding parts of machine reduces the friction.

3. THE USE OF BALL

Bearing In machines where possible, sliding friction can be replaced by rolling friction by using ball bearings.

4. THE DESIGN MODIFICATION

Friction can be reduced by changing the design of fast moving objects. The front of vehicles and airplanes made oblong to minimize friction.

### 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 pupils in groups or pairs depending on the size of the class.

3. Teacher asks pupils to rub the palms their hands together very firmly. What do you feel?

4. Teacher lets pupils apply lubricant on their palms and rub them together again. What is the different?

5. Teacher listens the pupils and uses their appropriate responses to introduce the lesson.

6. Teacher lets pupils repeat the activities in activity 4 and 5 on smooth and rough surfaces with a tin.

Pupil’s Activities – Identify frictions.

7. Teacher uses the activities on smooth and rough surfaces to introduce and discuss on the meaning and effects of frictional force.

Pupil’s Activities – Pay attention to the lesson introduction as teacher discuss the meaning and effects of frictional force.

8. Teacher uses objects such as tyre, bicycle break, handle, etc. to lead discussion on the advantages of frictional force.

9. Teacher asks pupils state the reasons why some of engines or machines make a lot of noise.

10. Teacher listens to the groups or pairs and uses their appropriate responses to lead a discussion on the disadvantages of friction.

Pupil’s Activities – Analyze the advantages and disadvantages of friction in their communities.

11. Teacher uses lubricant and grease to discuss ways to prevent friction.

Pupil’s Activities – State other ways of reducing friction.

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

Pupil’s Activities – Participate actively in the summary of the lesson by responding correctly to 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 (magnetic force).

### LESSON EVALUATION

1. explain the meaning of frictional force.

2. state 5 effects of friction.

3. mention 5 instance where friction is applicable in our daily activities;

4. list 4 advantages of friction.

5. state 4 disadvantages of friction.

6. mention 5 ways to reduce or prevent friction.