j3010 unit 0

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MALAYSIAN

POLYTECHNICS MINISTRY OF EDUCATION

MODULE JJ33001100

MMEECCHHAANNIICCSS OOFF MMAACCHHIINNEESS 11

Zainol Hashim (POLIMAS)

Harisa Mohamad Saad (POLIMAS)

J3010 MECHANICS OF MACHINES 1

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Name : Zainol Bin Hashim Address : Mechanical Engineering Department

Politeknik Sultan Abdul Halim

Mua’dzam Shah, Bandar Darulaman

06000 Jitra

Kedah Darulaman

Telephone No. : 04-9174701 ext.407

Qualifications : B Sc Mech. Eng.(UTM)

Diploma Mech. Eng (UTM)

Cert.Education

Position : Polytechnic Lecturer

Name : Harisa Bt Mohamad Saad

Address : Mechanical Engineering Department

Politeknik Sultan Abdul Halim

Muadzam Shah, Bandar Darulaman

06000 Jitra

Kedah Darulaman

Telephone No. : 04-9174701 ext.822

Qualifications : B Eng. Agricultural (Food and Process)

(UPM)

Masters in Education (ITTHO)

Position : Polytechnic Lecturer

BIODATA OF MODULE WRITERS J3010 Mechanics Machines


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What Do You Think Of This Module?

Title of Module: _______________________ Module Code : ___________ Student’s Name: _______________________ Registration No. : ___________ Course : ____________________________________ Module Writers: ______________________________ Please use the following scale for your evaluation:

4 Strongly Agree 3 Agree 2 Disagree 1 Strongly Disagree

Instruction : Please on the space provided.

No. How much do you agree with the following statements? SCALE

A. FORMAT 1 2 3 4

1 The pages are organized in an interesting manner.

2 The font size makes it easy for me to read the module.

3 The size and types of pictures and charts used are suitable for the input.

4 The pictures and charts are easy to read and understand.

5 The tables used are well-organised and easy to understand.

6 The arrangement of the Input makes it easy for me to follow.

7 All the instructions are displayed clearly.

B. CONTENTS 1 2 3 4

8 I understand all the objectives clearly.

9 I understand the ideas conveyed.

10 The ideas are presented in an interesting manner.

11 All the instructions are easy to understand.

12 I can carry out the instructions in this module.

13 I can answer the questions in the activities easily.

14 I can answer the questions in the self-assessment.

15 The feedback section can help me identify my mistakes.

16 The language used is easy to understand.

17 The way the module is written makes it interesting to read.

18 I can follow this module easily.

19 Each unit helps me understand the topic better.

20 I have become more interested in the subject after using this module.


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CURRICULUM GRID

The curriculum grid of this module is based on the curriculum used by Malaysian

polytechnics.

No. TOPIC UNIT Total

Hours

1

General

Dynamics

1

( 9 H)

9 Hours

2

Moment

Inertia

2

( 6 H)

6 Hours

3

Hoisting

system

3

( 6 H )

6 Hours

4

Friction

4

( 6 H )

6 Hours

5

Screw

5

(6 H )

6 Hours

6

Belting

6

( 9 H )

9 Hours


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UNIT 1 GENERAL DYNAMICS

1.1 Velocity and Acceleration

1.2 Equation for linear, uniformly accelerated motion

1.3 Relationship between linear speed and angular speed

1.4 Relationship between linear acceleration and

angular acceleration

1.5 Work done by a constant force

1.6 Power

1.7 Energy and conservation of energy

1.8 Momentum and conservation of momentum

UNIT 2 MOMENT OF INERTIA

2.1 Moment of Inertia

2.2 Theorem of Parallel axes

2.3 Theorem of Perpendicular axes

2.4 Moment of Inertia in a few simple cases

2.5 Torque and Angular Acceleration

2.6 Angular Momentum

2.7 Angular impulse

2.8 Work done by a torque

2.9 Angular kinetic energy

2.10 Kinetic energy of a torque

UNIT 3 HOISTING SYSTEM

3.1 Inertia Couple

3.2 Accelerated Shaft

3.3 Shaft being brought to rest

3.4 Load raised and with accelerating upward

3.5 Load falling and accelerating downwards (No driving torque

acting)

3.6 Load falling and being brought to rest

3.7 Load rising: Coming to rest under friction only

3.8 Load balancing system


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UNIT 4 FRICTION

4.1 Motion up the plane: pull P parallel to plane

4.2 Motion down the plane: Pull P parallel to plane

4.3 The angle of friction and total reaction

4.4 Application of angle of friction to motion on the inclined

plane

UNIT 5 SCREW

5.1 The square thread screw

5.2 The V- thread screw

5.3 Raising Load

5.4 Load being lowered

5.2 Overhauling of a screw

UNIT 6 BELTING

6.1 Length of an open belt drive

6.2 Length of cross belt drive

6.3 Power transmitted by a belt

6.4 Ratio of tensions

6.5 Centrifugal tension


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MODULE GUIDELINES

To achieve maximum benefits in using this module, students must follow the

instructions carefully and complete all the activities.

1. This module is divided into 6 units.

2. Each page is numbered according to the subject code, unit and page number.

J3010 / UNIT 1 / 5

Subject Unit 1 Page Number 5

3. The general and specific objectives are given at the beginning of each unit.

4. The activities in each unit are arranged in a sequential order and the

following symbols are given:

OBJECTIVES

The general and specific objectives for each learning topic are stated

in this section.

INPUT

This section introduces the subject matter that you are going to learn.

ACTIVITIES

The activities in this section test your understanding of the subject

matter. You have to complete this section by following the

instructions carefully.


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FEEDBACK

Answers to the questions in the activity section are given here

SELF-ASSESSMENT

Self-assessment evaluates your understanding of each unit.

FEEDBACK ON SELF-ASSESSMENT

This section contains answers to the activities in the self-assessment.

5. You have to follow the units in sequence.

6. You may proceed to the next unit after successfully completing the unit and

you are confident of your achievement.


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GENERAL AIMS

This module is prepared for students in the third or fourth semester who are

undergoing the Certificate/Diploma programmes in Malaysian Polytechnics. It aims

to expose students to the mechanics of machines concept in each unit and to lead

them towards self-directed learning or with guidance from their lecturers.

PRE REQUISITE SKILLS AND KNOWLEDGE

The pre-requisite for this module is at least a pass in Mathematic at the SPM level

and the successful completion of the Engineering Science module in the first

semester.

GENERAL OBJECTIVES

At the end of this module, students should be able to:

1. know principles and fundamental concept of general dynamics.

2. know method and procedures to solve problem of mechanics machines.

3. understand facts and principles all of these topics.

4. solve problem in relation to hoisting and friction.

5. solve problem of raising and lowering load for square and Vee threaded screw.

6. find the values of Belting by using a calculator.

TEACHING AIDS AND RESOURCES NEEDED

1. Calculator


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REFERENCES

1. John Hannah and M.J. Hillier (1971). Applied Mechanics; New Zealand

Pitman: Publishing Limited.

2. W. Madill (1984). Applied Mechanics Level 3; Longman Inc., New

York: Longman Group Limited.

3. D Humphrey and J Topping (1971). A Shorter Intermediate Mechanics;

London: Longman Group Ltd.

4. George E. Drabble (1971). Applied Mechanics; London: W.H. Allen & Co.

Ltd.

5. R.S. Khurmi (1988). A Text Book Of Applied Mechanics;New Delhi:

S. Chand & Company (Pvt) Ltd.

6. R.K. Mullis (1983). Engineering Mechanics; Longman Cheshire Pty.

7. S.B.Mathur (1979). Applied mechanics; Delhi: Khanna Publishers.

8. L.Bostock and S.Chandler (1979). Applied Mathematics; Scotland: Thomson

Litho Ltd.