Membership of the CDC Ad Hoc Committee on the Revision of S4-5 Physics Curriculum

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Membership of the Joint CDC and HKEA Working Party on the Revision of S4-5 Physics Syllabus

(From March 1997 to August 1999)

Chairperson: Mr LAU Hoi-kwan

Members: Dr CHAN Kwok-sum

Mr CHUNG Chuen-ming Mr KAN Chi-fai

Mr LEUNG Wah-wai Dr LAW LUK Wai-ying Mr NG Wai-cheung Mr TAM Chi-wing Mr TAM Ka-lok Mr TAM Yiu-wang Mr WONG Chi-kin Mr WONG Kim-wah

Senior Inspector, Education Department (Mr LAU Yuen-tan)

Senior Curriculum Officer, Education Department (Ms LUI Mong-yu)

Curriculum Officer, Education Department (Mr YU Hon-yui)

Secretaries: Curriculum Officer, Education Department (Mr LI Wai-kwok)

Subject Officer, Hong Kong Examinations Authority (Mr WAN Tak-wing)

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Membership of the CDC Ad Hoc Committee on the Revision of S4-5 Physics Curriculum

(Since December 1999)

Convenor: Curriculum Development Officer, Education Department (Mr YU Hon-yui)

Members: Dr HUI Pak-ming Mr KAN Chi-fai Mr KWONG Po-kit Mr LAU Hoi-kwan

Mr LAU Yiu-hon (September 2000 to August 2001) Dr PANG Wing-chung

Mr WONG Chi-kin (until June 2000) Senior Inspector, Education Department (Mr LAU Yuen-tan, until June 2000)

Senior Curriculum Development Officer, Education Department (Ms LUI Mong-yu, until June 2000)

(Mr LAU Yuen-tan, since July 2000)

Secretary: Curriculum Development Officer, Education Department (Mr LI Wai-kwok, until August 2001)

(Mr LAU Yiu-hon, since September 2001)

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Membership of the Joint CDC and HKEA Working Group on the Revision of S4-5 Physics Curriculum

(Since September 2000)

Chairperson: Mr SHUM On-bong

Members: Mr CHAN Wan-mo

Mr CHUNG Chuen-ming Ms CHUNG Yin-ping Mr HO Yau-sing Dr HUI Pak-ming Mr KAN Chi-fai Mr KWONG Po-kit Mr LAU Hoi-kwan

Mr LAU Yiu-hon (until August 2001) Mr LEUNG Wah-wai

Mr NG Wai-cheung Dr PANG Wing-chung

Senior Curriculum Development Officer, Education Department (Mr LAU Yuen-tan)

Curriculum Development Officer, Education Department (Mr YU Hon-yui)

Secretaries: Curriculum Development Officer, Education Department (Mr LI Wai-kwok, until August 2001)

(Mr LAU Yiu-hon, since September 2001)

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PREAMBLE

This Curriculum Guide is one of the series prepared by the Hong Kong Curriculum Development Council for use in secondary schools.

The Curriculum Development Council is an advisory body giving recommendations to the Hong Kong Special Administrative Region Government on all matters relating to curriculum development for the school system from kindergarten to sixth form. Its membership includes heads of schools, practising teachers, parents, employers, academics from tertiary institutions, professionals from related fields or related bodies, representatives from the Hong Kong Examinations Authority and the Vocational Training Council, as well as officers from the Education Department.

This Curriculum Guide is recommended by the Education Department for use in secondary schools. The curriculum developed for the senior secondary levels normally leads to appropriate examinations provided by the Hong Kong Examinations Authority.

The Curriculum Development Council will review the curriculum from time to time in the light of classroom experiences. All comments and suggestions on the Curriculum Guide may be sent to:

Chief Curriculum Development Officer (Science) Education Department

4/F., 24 Tin Kwong Road Kowloon

Hong Kong

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1

I. AIMS AND OBJECTIVES

Aims

The paramount aim of the science education in Hong Kong is to provide learning experiences for students to engage in scientific processes for understanding and application of scientific concepts and principles, and recognise the impact and cultural significance of scientific and technological developments. These learning experiences will form a solid foundation on which students communicate ideas and make informed judgements, develop further in the field of physics, science and technology, and become life-long learners in these fields of study.

The broad aims of this physics curriculum are to enable students to

— develop interest, motivation and a sense of achievement in their study of physics;

— develop an appreciation of the nature of physics, the historical and current development in physics;

— understand the fundamental principles and concepts of physics and its methodology;

— develop an awareness of the relevance of physics to their daily life;

— acquire the basic scientific knowledge and concepts for living in and contributing to a scientific and technological world;

— recognise the usefulness and limitations of science and the interactions between science, technology and society;

— develop an attitude of responsible citizenship, including respect for the environment and commitment to the wise use of resources;

— develop the ability to describe and explain concepts, principles, systems, processes and applications related to physics using appropriate terminologies;

— develop skills relevant to the study of physics such as scientific investigation, problem solving, experimental technique, collaboration, communication, mathematical analysis, information searching and processing, analytical and critical thinking and self-learning;

— develop positive values and attitudes towards physics, themselves and others through the study of physics;

— carry out further studies and embark upon careers in fields related to physics; and

— recognise the role of the applications of physics in the fields of science, engineering and technology.

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Objectives

The following is a schematic inter-relationship diagram on the Objectives of the physics curriculum:

— Heat

— Mechanics

— Waves

— Electricity and Magnetism

— Atomic Physics

— towards themselves and others

— towards physics and the world

— towards learning

Learning Objectives

Skills and Processes

— scientific thinking

— scientific investigation

— practical

— problem solving

— information handling

— learning and self-learning

— communication

— collaboration Values and

Attitudes Knowledge and

Understanding

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3

The general objectives listed below are to be developed through a course of study of physics at S4-5 level as a whole. They are categorized into three domains: Knowledge and Understanding, Skills and Processes, and Values and Attitudes. Being at a general level, they are applicable to all the sections of the physics curriculum. Objectives specifically related to individual sections will be highlighted in the chapter on CURRICULUM FRAMEWORK.

A. Knowledge and Understanding

Students should be able to

1. recall terms, facts, concepts, principles, theories and models in physics;

2. show understanding of the subject using physics vocabulary and terminology;

3. show knowledge of techniques and skills specific to the study of physics;

4. apply knowledge and principles of physics to familiar and unfamiliar situations; and 5. show understanding of the technological applications of physics and of the social

implications of these.

B. Skills and Processes

1. scientific thinking

1.1 identify attributes of objects or natural phenomena;

1.2 identify patterns and changes in the natural world and predict trends from them;

1.3 examine evidence and apply logical reasoning to draw valid conclusions;

1.4 present concepts of physics in mathematical terms whenever appropriate;

1.5 appreciate the fundamental role of models in exploring observed natural phenomena;

1.6 appreciate that models are modified as new or conflicting evidences are found;

1.7 examine theories and concepts through logical reasoning and experimentation;

1.8 recognise preconceptions or misconceptions with aid of experimental evidence; and 1.9 group and organise knowledge and concepts and apply to new situations.

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2. scientific investigation

2.1 ask relevant questions in scientific investigations;

2.2 propose hypotheses for scientific phenomena and devise methods to test them;

2.3 identify dependent and independent variables in investigations;

2.4 devise plans and procedures to carry out investigations;

2.5 select appropriate methods and apparatus to carry out investigations;

2.6 observe and record experimental observations accurately and honestly;

2.7 organise and analyse data, and infer from observations and experimental results;

2.8 use graphical techniques appropriately to display experimental results and to convey concepts of physics;

2.9 produce reports on investigations, draw conclusions and make further predictions;

2.10 evaluate the quality and reliability of experimental results and identify factors affecting their quality and reliability; and

2.11 propose plans for further investigations if appropriate.

3. practical

3.1 follow procedures to carry out laboratory experiments;

3.2 handle apparatus properly and safely;

3.3 measure to the accuracy allowed by the instruments; and 3.4 recognise the limitations of instruments used.

4. problem solving

4.1 clarify and analyse problems related to physics;

4.2 apply knowledge and principles of physics to solve problems;

4.3 suggest creative ideas or solutions to problems;

4.4 propose solution plans and evaluate the feasibility of these plans; and 4.5 devise appropriate strategies to deal with issues that may arise.

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5. information handling

5.1 search, retrieve, reorganise, analyse and interpret scientific information from libraries, the media, the Internet and multi-media software packages;

5.2 use information technology to manage and present information, and to develop habits of self-learning;

5.3 be wary of the accuracy and credibility of information from secondary sources; and 5.4 distinguish among fact, opinion and value judgement in processing scientific

information.

6. learning and self-learning

6.1 develop their study skills to improve the effectiveness and efficiency of learning;

6.2 engage in simple self-learning activities in the study of physics; and

6.3 develop basic learning habits, abilities and attitudes that are essential to the foundation of life-long learning.

7. communication

7.1 read and understand articles involving physics terminology, concepts and principles;

7.2 use appropriate terminology to communicate information related to physics in oral, written or other suitable forms; and

7.3 organise, present and communicate physics ideas in a vivid and logical manner.

8. collaboration

8.1 participate actively, share ideas and offer suggestions in group discussions;

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8.2 liaise, negotiate and compromise with others in group work;

8.3 identify collective goals, define and agree on roles and responsibilities of members in science projects requiring team work;

8.4 act responsibly to accomplish allocated tasks;

8.5 be open and responsive to ideas and constructive criticisms from team members;

8.6 build on the different strengths of members to maximize the potential of the team;

8.7 demonstrate willingness to offer help to less able team members and to seek help from more able members; and

8.8 implement strategies to work effectively as a member of the project team.

C. Values and Attitudes

1. towards themselves and others

Students should

1.1 develop and possess positive values and attitudes such as curiosity, honesty, respect for evidence, perseverance and tolerance of uncertainty through the study of physics;

1.2 develop a habit of self-reflection and the ability to think critically;

1.3 be willing to communicate and comment on issues related to physics and science;

1.4 develop open-mindedness and be able to show tolerance and respect towards the opinions and decisions of others even in disagreement; and

1.5 be aware of the importance of safety for themselves and others and be committed to safe practices in their daily life.

2. towards physics and the world we are living in

Students should

2.1 appreciate the achievements made in physics and recognise the limitations;

2.2 accept the provisional status of the knowledge and theory of physics;

2.3 apply the knowledge and understanding of physics rationally in making informed decision or judgement on issues in their daily life; and

2.4 be aware of the social, economic, environmental and technological implications of the achievement of physics.

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3. towards learning as a life-long process

Students should

3.1 recognise the consequences of the evolutionary nature of scientific knowledge and understand that the constant up-dating of knowledge is important in the world of science and technology;

3.2 be exposed to and develop an interest in the new developments of physics, science and technology; and

3.3 recognise the importance of life-long learning in our rapidly changing knowledge-based society.

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II. CURRICULUM FRAMEWORK

A. Organisation

The physics curriculum builds on the CDC Syllabus for Science (Secondary 1-3) published in 1998, in which some basic physics concepts on Forces and Motion, Energy, Electricity and Light have been introduced. The fundamental principles of these topics are further developed in this curriculum. Other topics are also covered to provide a coherent and comprehensive view of the world of physics.

1. Domains

The physics curriculum consists of three domains: Knowledge and Understanding, Skills and Processes, and Values and Attitudes. Objectives for these domains, which are described in detail in the chapter on AIMS AND OBJECTIVES, contribute to the whole personal development of a student. Students are to acquire and integrate the concepts and skills from various parts of the curriculum in order to develop a coherent and holistic view of physics.

Ideas as well as materials from social issues and everyday experiences of students should be incorporated to fulfil the objectives.

2. Core and Extension

The content of the curriculum consists of two components, Core and Extension. The Core is the basic component of senior secondary level physics for all students whereas the Extension component is generally more demanding and more suitable for students aiming to pursue further study in the subject. For some students, it will be more beneficial, less stressful and more effective to just concentrate on the Core component so that more time is available to master the basic concepts and principles; for others, the challenges provided by the Extension component may provide a higher degree of achievement. A good school-based physics course should have an in-built flexibility to cater for the interest and abilities of students so that a balance between the quantity and quality of learning may be achieved.

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3. Experiments and Investigations

Scientific investigations and experiments are essential to the study of physics. Through hands-on practical activities, students are expected to acquire science practical skills identified in the chapter on AIMS AND OBJECTIVES and detailed in the individual sections. By participating in the process of scientific enquiry, students will bring the scientific method to the processes of problem solving, decision-making and evaluation of evidence. A good school-based physics course should be organised to provide a significant amount of experimental and investigational work so that students have opportunities to develop their practical skills as well as higher order thinking skills. Teachers may design or adopt experiments and investigations to bring out the teaching points in an effective manner.

In particular, experiments and investigations closely related to relevant contexts will enha nce learning effectiveness.

All practical work should be performed by students under proper teacher supervision to ensure that safety measures are observed. Teachers are advised to try out new or unfamiliar experiments beforehand so that any potentially dangerous situations can be uncovered before students are involved.

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B. Time Allocation

A time allocation of four 40-minute periods each week for Secondary 4 and 5 would be adequate to cover this curriculum. The time allocation below is compiled for the entire physics curriculum consisting of both the Core and the Extension components. It gives an estimation of the number of periods required to cover the individual sections. Project work, presentation, discussion and article reading are importa nt elements of this curriculum.

Whereas some of these activities may be conducted by students themselves outside normal school hours, about 30 periods could be set aside for these activities within normal curriculum time. Teachers should integrate these elements into the curriculum appropriately.

No. of Periods Project work, presentation, discussion, article reading 30

Section 1 Heat 18

1.1 Temperature, Heat and Internal Energy 1.2 Transfer Processes

1.3 Change of State

Section 2 Mechanics 45

2.1 Position and Movement 2.2 Force and Motion 2.3 Work, Energy and Power 2.4 Momentum

Section 3 Waves 42

3.1 Nature and Properties of Waves 3.2 Light

3.3 Sound

Section 4 Electricity and Magnetism 42

4.1 Electrostatics

4.2 Circuits and Domestic Electricity 4.3 Electromagnetism

Section 5 Atomic Physics 15

5.1 Radiation and Radioactivity 5.2 Atomic Model

5.3 Nuclear Energy

Total: 192

(Equivalent to 128 hours)

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C. Content

The content of the curriculum is organised into five sections. However, the concepts and principles of physics, being inter-related, cannot be confined by any artificial boundaries of the sections. In the knowledge content of each section, sub-topics that are assigned to the Extension component are underlined. The order of presentation of the sections, or the materials within each section, should not be regarded as the recommended teaching sequence.

Teachers should adopt sequences that best suit their chosen teaching approaches. For instance, some parts of a certain section may be covered in advance if they fit in naturally within a chosen context.

There are five major parts in each of the following sections: Overview, Knowledge and Understanding, Skills and Processes, Values and attitudes and Science, Technology and Society (STS) connections.

(a) Overview – outlines the main theme of the section. The major concepts and important physics principles to be acquired will be highlighted. The foci of each section will be briefly described. The interconnections between sub-topics will also be outlined.

(b) Knowledge and Understanding – lists out what are the major topics required in the knowledge content domain of the syllabus. It provides a broad framework upon which learning and teaching activities can be developed.

(c) Skills and Processes – gives suggestions to some of the different skills that are expected to be acquired in the section. Some important processes associated with the section are also briefly described. Since most of the generic skills can be acquired through any of the sections, there is no attempt to give directive recommendation on the activities that should be performed. Students need to acquire a much broader variety of skills than what are mentioned in the sections. Teachers should use their professional judgement to arrange practical and learning activities to develop the skills of students as listed in the chapter on AIMS AND OBJECTIVES. It should be done through an appropriate integration with the knowledge content, taking into consideration students’ abilities and interest as well as school contexts.

(d) Values and Attitudes – suggests some desirable values and attitudes related to the section.

Students are expected to develop such intrinsically worthwhile values and positive attitudes in the course of a study in physics. Through discussions and debates, students are encouraged

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to form their value judgement and develop good habits for the benefit of themselves and society.

(e) STS connections – suggests some issue-based learning activities related to the topics in the section. Students should be encouraged to develop an appreciation and apprehension of issues which reflect the interconnections of science, technology and society. Through discussion, debate, information search and project work, students can develop their skills of communication, information handling, critical thinking and making informed judgement.

Teachers are free to select other current, relevant topics and issues of high profile in the public agenda as themes of meaningful learning activities.

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Section 1 Heat

Overview

This section examines the concept of internal energy and energy transfer processes related to heat. Particular attention is placed on the distinction and relationship between temperature, internal energy and energy transfer. Students are also encouraged to adopt microscopic interpretations of various important concepts on the topic of heat.

Calculations involving specific heat capacities will be used to complement the theoretical aspects of heat and energy transfer. The practical importance of the high specific heat capacity of water can be illustrated with examples close to the experiences of students. A study of conduction, convection and radiation provides a basis for analysing the containment of internal energy and transfer of energy related to heat. The physics involving the change of states is examined and numerical problems involving the specific latent heat are used to consolidate the theoretical aspects of energy conversion.

Knowledge and Understanding

Students should learn:

1.1 Temperature, heat and internal energy

temperature and thermometers

— temperature as the degree of hotness of an object

— interpretation of temperature as a quantity associated with average kinetic energy due to the random motion of the molecules in a system

— use of temperature-dependent properties to measure temperature

— degree Celsius as a unit of temperature

— fixed points on the Celsius scale

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heat and

internal energy

— heat as the energy transferred resulting from the temperature difference between two objects

— internal energy as the energy stored in a system

— interpretation of internal energy as the sum of the kinetic energy of random motion and the potential energy of the molecules in a system

heat capacity and specific heat capacity

— definitions of heat capacity and specific heat capacity

— application of the formula Q = mc(T₂-T₁) to solve problems

— practical importance of the high specific heat capacity of water

1.2 Transfer processes

conduction, convection and radiation

— conduction, convection and radiation as means of energy transfer

— interpretation, in terms of molecular motion, of energy transfer by conduction in solids and by convection in fluids

— emission of infra-red radiation by hot objects

— factors affecting the emission and absorption of radiation

1.3 Change of state

melting and freezing, boiling and condensing

— melting point and boiling point

latent heat — latent heat as the energy transferred during a change of state at constant temperature

— interpretation of latent heat in terms of the change of potential energy of the molecules during a change of state

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— definitions of specific latent heat of fusion and specific latent heat of vaporization

— application of the formula Q = mL to solve problems evaporation — occurrence of evaporation below boiling point

— cooling effect of evaporation

— factors affecting rate of evaporation

— interpretation of evaporation in terms of molecular motion

Skills and Processes

Students should develop experimental skills in temperature and energy measurements. The precautions essential for accurate measurements in heat experiments should be understood in terms of the concepts learnt in this section. Students should also be encouraged to suggest their own methods for improving the accuracy of these experiments, and arrangements for performing these investigations should be made if they are feasible. In some of the experiments, a prior understanding of electrical energy may be required to provide a firm understanding of the energy transfer processes involved.

Values and Attitudes

Students should develop intrinsically worthwhile values and attitudes in the course of a study in physics; some particular examples are:

— to be aware of the proper use of heat-related domestic appliances as it helps to reduce the cost of electricity and contributes to the worthwhile cause of saving energy

— to be aware of the large amount of energy associated with heat transfer and to develop good habits when using air-conditioning in summer and heating in winter

— to develop an interest in alternative environment friendly energy resources such as solar cookers and geothermal energy

— to be aware of the importance of home safety in relation to the use of radiation heaters and

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to be committed to safe practices in their daily life

STS connections

Students are encouraged to develop an appreciation and apprehension of issues which reflect the interconnections of science, technology and society; some examples of such issues and topics related to this section are:

— the importance of greenhouses in agriculture and the environmental issue of the

‘Greenhouse Effect’

— debates on the gradual rise in global temperature due to human activities, the associated potential global hazard due to the melting of the polar ice caps, and the effects on the world’s agricultural production

— projects, such as the ‘Design of Solar Cookers’, can be used to develop the investigation skill as well as to foster the concept of using alternative environment friendly energy resources

(Note: The underlined text represents the extension part of the curriculum.)

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Section 2 Mechanics

Overview

In this section, the fundamentals of mechanics are introduced, and the foundation for describing motion with physics terminologies is laid. Various types of graphical representations of motion are studied. Students learn how to analyse different forms of motion and solve simple problems relating to uniformly accelerated motion. They also learn the rules governing the vertical motion of objects on Earth.

The concept of inertia and its relation to Newton’s first law of motion is covered. Simple addition and resolution of forces are used to illustrate the vector properties of forces, and free-body diagrams are used to work out the net force acting on a body. Newton’s second law of motion, which relates the acceleration of an object to the net force, is examined. The concepts of mass, weight and gravitational force are introduced. Newton’s third law of motion is related to the nature of forces.

The concepts of mechanical work done and energy transfer are examined and used in the derivation of kinetic energy and gravitational potential energy. The treatment of energy conversion is used to illustrate the law of conservation of energy, and the concept of power is also studied. Students learn how to compute quantities such as momentum and energy in examples on collisions. The relationship between the change in momentum of a body, impact time and impact force is emphasised.

2.1 Position and movement

position, distance and displacement

— description of the change of position of objects in terms of distance and displacement

— displacement-time graphs for moving objects

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scalars and vectors — distinction between scalar and vector quantities

— use of scalars and vectors in different contexts speed and velocity — average speed and average velocity

— distinction between instantaneous and average speed /velocity

— description of motion of objects in terms of speed and velocity

uniform motion — definition of uniform motion

— application of the formula s = vt for uniform motion

— velocity-time graphs of objects in uniform motion

acceleration — velocity-time graphs of objects in uniformly accelerated motion in one direction and with a change in direction (including the interpretation of slope and area)

— definition of acceleration as the rate of change of velocity

— formula

t u

a=v− for uniformly accelerated motion along a straight line

— acceleration-time graphs of objects in uniformly accelerated motion in one direction and with a change in direction

equations of uniformly accelerated motion

— equations of uniformly accelerated motion at

u v= +

t v u s = ₂¹( + )

2 2 1at ut s = +

as u

v² = ² +2

— problem solving of uniformly accelerated motion for journeys in one direction and with a change in direction

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vertical motion under gravity

— free-falling objects have the same acceleration (g)

— description and graphical representation of vertical motions of free-falling objects in one direction and with a change in direction

— problem solving of vertical motions in one direction and with a change in direction using the equations of uniformly accelerated motion

— qualitative treatment of the effect of air resistance on the motion of objects falling under gravity

2.2 Force and motion

Newton’s first law of motion

— meaning of inertia and mass

— Newton’s first law of motion

— application of the first law to explain situations in which objects are at rest or in uniform motion

— friction as a force opposing relative motion between 2 surfaces

addition of forces — addition of forces graphically and algebraically in one dimension

— addition of forces graphically and algebraically in two dimensions

resolution of forces — resolution of a force graphically and algebraically in two mutually perpendicular directions

Newton’s second law of motion

— effect of a net force on the speed and direction of motion of an object

— Newton’s second law of motion and the equation F = ma

— definition of a unit of force, newton

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— use of free-body diagrams to show the forces acting on objects and to identify the net force in a system consisting of one or two objects

— application to solve problems involving rectilinear motion in one direction and with a change in direction

Newton’s third law of motion

— forces act in pairs

— Newton’s third law of motion

— identification of the action and reaction pair of forces mass and weight — distinction between mass and weight

— relationship between mass and weight W = mg

2.3 Work, energy and power

mechanical work — mechanical work done as a measure of energy transfer

— definition of mechanical work done W = Fs

— definition of a unit of energy, joule, with reference to the equation W = Fs

— application of the formula W = Fs to solve problems gravitational potential

energy (P.E.)

— gravitational potential energy of an object due to its position under the action of gravity

— derivation of the formula E_P = mgh

— application of the formula E_P = mgh to solve problems kinetic energy (K.E.) — kinetic energy of a moving object

— derivation of the formula E_K = ₂¹mv²

— application of the formula E_K =₂¹mv² to solve problems

law of conservation of energy

— interpretation of the law of conservation of energy

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— inter-conversion of P.E. and K.E., taking into account of energy loss

— application of the law of the conservation of energy to solve problems

power — definition of power in terms of the rate of energy transfer

— definition of a unit of power, watt

— application of the formula t

P=W to solve problems

2.4 Momentum

linear momentum — definition of momentum as a quantity of motion of an object p = mv

change in momentum and net force

— change in momentum resulted when a net force acts on an object for a period of time

— interpretation of force as the rate of change of momentum (Newton’s second law of motion)

law of conservation of momentum

— interpretation of the law of conservation of momentum

elastic and inelastic collisions

— distinction between elastic and inelastic collisions

— application of the law of conservation of momentum to solve problems involving collisions in one dimension

— energy changes in collisions

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Students should develop experimental skills in time measurements and in the recordings of positions, velocities and accelerations of objects using various types of measuring instruments such as stop watches, data-logging sensors etc. Skills in the measurements of masses, weights and forces are also required. Data handling skills such as converting displacement and time data into information on velocity or acceleration are important. Students may be encouraged to carry out project-type investigations in the motion of vehicles. There is much emphasis on the importance of graphical representations of physical phenomena in this section. Students should learn how to plot graphs with suitable choices of scales, display experimental results in graphical forms and interpret, analyse and draw conclusions from graphical information. In particular, they should learn to interpret the physical significances of slopes, intercepts and areas in certain graphs.

— to be aware of the importance of car safety and to be committed to safe practices in their daily life

— to be aware of the potential danger of falling objects from high-rises and to adopt a cautious attitude in matters concerning public safety

— to be aware of the environmental implications of the different modes of transport and to make an effort in reducing energy consumptions in daily life

— to appreciate the efforts made by scientists to find more alternative environment friendly energy resources

— to appreciate that the advancement of important scientific theories (such as Newton’s laws of motion) can ultimately make huge impacts on technology and society

— to appreciate the roles of science and technology in the exploration of outer-space and to appreciate the efforts of mankind in the quest for the understanding of nature

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STS connections

— the effects of energy use on the environment

— the reduction of pollutants and energy consumption by restricting the use of private cars in order to protect the environment

— the penalizing of drivers and passengers who do not wear seatbelts and the raising of public awareness of car safety with scientific rationales

— how the danger of speeding, and its relation to the chances of serious injury or death in car accidents, can be related to the concepts of momentum and energy

— modern transport: the dilemma in choosing between speed and safety; the dilemma in choosing between convenience and protection of the environment

— the ethical issue of dropping objects from high-rises and its potential danger based on the principles of physics

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Section 3 Waves

Overview

This section examines the basic nature and properties of waves. Li ght and sound, in particular, are studied in detail. The concept of waves being a means of transmitting energy without transferring matter is emphasised. The foundation for describing wave motion with physics terminologies is laid. Students learn the graphical representations of travelling waves. The basic properties and characteristics displayed by waves are examined; reflection, refraction, diffraction and interference are studied using simple wavefront diagrams.

Students acquire a specific knowledge on light in two important aspects. The characteristics of light as a part of the electromagnetic spectrum are studied. Besides, the linear propagation of light in the absence of significant diffraction and interference effects is used to explain image formation in the domain of geometric optics. The formation of real and virtual images using mirrors and lenses are studied using the construction rules for light rays.

Sound as an example of longitudinal waves is examined. Its general properties are comp ared with those of light waves. Students also learn about ultrasound. The general descriptions of musical notes are related to the terminologies of waves. The effects of noise pollution and the importance of acoustic protection are also studied.

3.1 Nature and properties of waves

nature of waves — oscillations in a wave motion

— waves transmitting energy without transferring matter

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wave motion and propagation

— distinction between transverse and longitudinal travelling waves

— description of wave motions in terms of: waveform, crest, trough, compression, rarefaction, wavefront, displacement, amplitude, period (T), frequency (f), wavelength (λ), wave speed (v)

— displacement-time and displacement-distance graphs for travelling waves

— application of f = 1/T and v = fλ to solve problems reflection, refraction

and diffraction

— reflection of waves at a plane barrier/reflector

— refraction of waves across a straight boundary

— refraction of waves due to a change in speed

— diffraction of waves through a narrow gap and around a corner

— relationship between the degree of diffraction and size of the gap compared to the wavelength

— illustration of reflection, refraction and diffraction of waves using wavefront diagrams

interference of waves — interference of waves as a property of waves

— occurrence of constructive and destructive interferences

— interference of waves from two coherent sources

— conditions for constructive and destructive interference in terms of path difference

— illustration of interference of waves using wavefront diagrams

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3.2 Light

wave nature of light — light as an example of transverse waves

— light as a part of the electromagnetic spectrum

— range of the wavelength for visible light

— relative positions of visible light and the other parts of the electromagnetic spectrum

— speed of light and electromagnetic waves in vacuum reflection of light — laws of reflection

— graphical constructions of image formation by a plane mirror

refraction of light — laws of refraction

— path of a ray being refracted at a boundary

— definition of refractive index of a medium n = sin i / sin r

— application of Snell’s law to solve problems involving refraction at a boundary between vacuum(or air) and another medium

total internal reflection — conditions for total internal reflection

— problem solving involving total internal reflection and critical angle at a boundary between vacuum(or air) and another medium

formation of images by lenses

— graphical constructions of image formation by converging and diverging lenses

— distinction between real and virtual images evidence for the wave

nature of light

— diffraction and interference as evidences for the wave nature of light

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3.3 Sound

wave nature of sound — sound as an example of longitudinal waves

— requirement of a medium for the transmission of sound waves

— comparison of the general properties of sound waves and light waves

audible sound — range of frequency for audible sound waves ultrasound — frequencies of ultrasound

musical notes — comparison of musical notes using the terms pitch, loudness and quality

— association of the frequency and amplitude with the pitch and loudness of a note respectively

noise — representation of the sound intensity level using the unit decibel

— effects of noise pollution and the importance of acoustic protection

Students should develop experimental skills in the study of vibration and waves through various physical models. They need to develop the skills for interpreting indirect measurements and demonstrations of wave motion through the displays on a CRO or computer. They should appreciate that many scientific evidences are obtained through indirect measurements coupled with logical deduction. They should also be aware that various theoretical models are used in the study of physics; for example, the ray model is used in geometric optics for image formation and the wave model of light is used to explain such phenomena as diffraction and interference. Through the study of the physics of musical

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notes, students should develop an understanding that most everyday experiences are explainable with the aid of scientific concepts.

— to appreciate the need to use more alternative environment friendly energy resources such as solar cells and tidal-wave energy

— to be aware that science has its limitations and cannot always provide clear-cut solutions;

the advancement of science also requires perseverance, openness and scepticism, as demonstrated in the different interpretations on the nature of light in the history of physics over the past centuries

— to appreciate that the advancement of important scientific theories (such as those related to the study of light) are the fruits of generations of scientists who devoted their lives to scientific investigations by applying their intelligence, knowledge and skills

— to be aware of the potential health hazard of a prolonged exposure to extremely loud noisy environment and to make an effort to reduce noise-related disturbances to neighbours

— to be aware of the importance of the proper use of microwave ovens and to be committed to safe practices in their daily life

STS connections

— controversial issues about the effects of microwave radiation on the health of the general public through the use of mobile phones

— the biological effects on the human body of an increased ultra-violet radiation from the Sun as a result of the formation of the depletion of ozone layer of the atmosphere caused by artificial pollutants

— the problem of noise pollution in the local context

— the impact on the society as a result of the scientific discovery of electromagnetic waves and the technological advancements in the area of telecommunication

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— how major breakthroughs in scientific and technological development that eventually affect society are associated with new understanding of fundamental physics as traced out by the study of light in the history of science

— how technological advancements can provide impetus for scientific investigations as demonstrated in the invention and development of the microscope, telescope and X-ray diffraction etc.; these scientific investigations in turn shed light on our own origin and the position of mankind in the universe

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Section 4 Electricity and Magnetism

Overview

This section examines the basic principles of electricity and magnetism. The abstract concept of an electric field is introduced through its relationship with an electrostatic force.

The inter-relationships between voltage, current, resistance, charge, energy and power are examined and a foundation for basic circuitry is laid. The practical use of electricity in households is studied with particular emphasis on the safety aspects.

The concept of magnetic field is applied to a study of electromagnetism. The magnetic effect of an electric current and some simple magnetic field patterns are studied. Students also learn the factors that affect the strength of an electromagnet. The magnetic force produced when a current-carrying conductor is placed in a magnetic field is studied and an application of the principle is used to understand the operation of a simple d.c. motor.

The general principles of electromagnetic induction are introduced, and the operation of simple d.c. and a.c. generators are studied. Students learn how a.c. voltages can be stepped up or down using transformers. The system by which electrical energy is transmitted over great distances to our homes is studied.

4.1 Electrostatics

electric charges — experimental evidences for two kinds of charges in nature

— attraction and repulsion between charges

— representation of a quantity of charge using the unit coulomb

— charging in terms of electron transfer

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electric field — existence of an electric field in the region around a charged body

— representation of an electric field using field lines

4.2 Circuits and domestic electricity

electric current — an electric current as a flow of electric charges

— definition of a unit of current, ampere, as one coulomb per second

— convention for the direction of an electric current electrical energy and

voltage

— energy transformations in electric circuits

— definition of voltage as the energy transferred per unit charge passed

— volt as a unit of voltage resistance and

Ohm’s law

— Ohm’s law

— definition of resistance R = V/I

— ohm as a unit of resistance

— application of the formula V = IR to solve problems

— factors affecting the resistance of a wire series and parallel

circuits

— comparison of series and parallel circuits in terms of the voltages across the components of each circuit and the currents through them

— relationships

R = R₁ + R₂ + ….. for resistors connected in series ...

1 1 1

2 1

+ +

= R R

R . for resistors connected in parallel

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simple circuits — determination of I, V and R in simple circuits

— effects of resistance of ammeters, voltmeters and cells in simple circuits

electrical power — heating effect when a current passes through a conductor

— application of the formula P = VI to solve problems

domestic electricity — power rating of electrical appliances

— kilowatt-hour (kW h) as a unit of electrical energy

— calculation of the costs of running various electrical appliances

— household wiring and the safety aspects of domestic electricity

— operating current for an electrical appliance and the selection of power cable and fuse

4.3 Electromagnetism

magnetic force and magnetic field

— attraction and repulsion between magnetic poles

— existence of a magnetic field in the region around a magnet

— representation of a magnetic field using field lines

— behaviour of a compass in a magnetic field magnetic effect of an

electric current

— existence of a magnetic field due to moving charges and electric currents

— magnetic field patterns associated with currents through a long straight wire, a circular coil and a long solenoid

— factors affecting the strength of an electromagnet

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current-carrying

conductor in a magnetic field

— existence of a force on a current-carrying conductor in a magnetic field and determination of its direction

— factors affecting the force on a current-carrying conductor in a magnetic field

— turning effect on a current-carrying coil in a magnetic field

— operating principle of a simple d.c. motor electromagnetic

induction

— induction of voltage when a conductor cuts magnetic field lines and when the magnetic field through a coil changes

— application of Lenz’s law to identify the direction of an induced current in a closed circuit

— operating principles of simple d.c. and a.c. generators transformer — operating principle of a simple transformer

— relationship between the voltage ratio and turns ratio V_p

V_s = N_p

N_s and its application to solve problems

— efficiency of a transformer

— methods for improving the efficiency of a transformer high voltage

transmission of electrical energy

— advantage of the transmission of electrical energy with a.c. at high voltages

— various stages of stepping up and down of the voltage in a grid system for power transmission

Students should develop experimental skills in connecting up circuits. They are required to perform electrical measurements using various types of equipment such as ammeters, voltmeters, multi-meters, joulemeter, CRO and data-logging probes. Students should acquire the skills in setting up experiments to study, demonstrate and explore the concepts of physics

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such as electric fields, magnetic fields and electromagnetic induction. Students can gain practical experiences related to design and engineering in building physical models such as electric motors and generators. It should, however, be noted that all experiments involving the mains power supply and EHT supply must be carefully planned to avoid the possibility of an electric shock, and that handling apparatus properly and safely is a very basic practical skill of great importance.

— to appreciate that the application of scientific knowledge can produce useful practical products and transform the daily-life of human beings as demonstrated in the numerous inventions related to electricity

— to be aware of the importance of technological utilities such as electricity to the modern society and the effects on modern life if these utilities are not available for whatever reason

— to be aware of the need to save electrical energy for reasons of economy as well as environmental protection

— to be committed to the wise use of natural resources and to develop a sense of shared responsibility for a sustainable development of mankind

— to be aware of the danger of electric shocks and the fire risk associated with an improper use of electricity and develop good habits in using domestic electricity

STS connections

— the effects on health as a result of living near high power transmission cables

— the potential hazard of the mains supply versus the conveniences of ‘plug-in’ energy and automation it offers to society

— the environmental implications and recent developments of the electric car as an alternative to the traditional fossil-fuel car; the role of government on such issues

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— the views of some environmentalists on the necessity to return to a more primitive or natural life-style with minimum reliance on technology

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Section 5 Atomic Physics Overview

In this section, atomic processes are examined. A simple model of the atom is used to explain some of the processes, and the origin of radioactivity, together with the nature and properties of radiation, are studied. Students learn simple methods for the detection of radiation as well as the major sources of background radiation in our natural environment.

Simple numerical problems involving half-lives are performed and used to understand the long-term effects of some radioactive sources. The potential hazard of ionizing radiation is studied scientifically and in a balanced way by bringing in the concept of dosage.

In the atomic model, the basic structure of a nuclide is represented using a symbolic notation.

Students learn the concepts of isotopes. They are also introduced to fission and fusion, nature’s most powerful energy sources.

5.1 Radiation and Radioactivity

X-ray — X-ray as an ionizing electromagnetic radiation of short wavelength with high penetrating power

— emission of X-rays when fast electrons hit a heavy metal target

α, β and γ radiation ^— origin and nature of the α, β and γ radiation

— comparisons of the α, β and γ radiation in terms of penetrating power, range, ionizing power, deflections in electric and magnetic fields, and cloud chamber tracks

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radioactive decay — occurrence of radioactive decay in unstable nuclides

— random nature of radioactive decay

— proportional relationship between the activity of a sample and the number of undecayed nuclei

— definition of half-life

— determination of the half-life of a radioisotope from its decay graph or from numerical data

— problem solving involving the half-life

detection of radiation — detection of radiation using a photographic film and G-M counter

— measurement of radiation in terms of the count rate using a G-M counter

radiation safety — major sources of the background radiation

— representation of a radiation dose using the unit sievert

— potential hazard of ionizing radiation and the ways to minimize the radiation dose absorbed

— safety precautions in handling radioactive sources

5.2 Atomic model

atomic structure — structure of a typical atom

— definitions of atomic number and mass number

— use of symbolic notations to represent nuclides isotopes and radioactive

transmutation

— definition of isotope

— existence of radioactive isotopes in some elements

— representation of radioactive transmutations in α, β and γ decays in terms of equations

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5.3 Nuclear energy

nuclear fission — release of energy in a nuclear fission

— nuclear chain reaction

nuclear fusion — release of energy in a nuclear fusion

— nuclear fusion as the source of solar energy

Students must be properly warned about the potential danger of radioactive sources. The regulations regarding the use of radioactivity for school experiments must be strictly observed.

Although students are not allowed to handle sealed sources, they can acquire experimental skills by participating in the use of the Geiger-Muller counter in an investigation of the background radiation. Fire alarms making use of weak sources may also be used in student experiments under teacher supervision. However, proper procedures should be adopted and precautions should be taken to avoid accidental detachment of the source from the device.

Analytic skills are often required to draw meaningful conclusions from the results of radioactive experiments that inevitably involve the background radiation.

Students should develop intrinsically worthw hile values and attitudes in the course of a study in physics; some particular examples are:

— to be aware of the usefulness of models and theories in physics as shown in the atomic model and appreciate the wonders of nature

— to be aware of the need to use natural resources judiciously to ensure the quality of life for future generations

— to be aware of the benefits and disadvantages of nuclear energy resources compared to fossil fuels

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— to be aware of the views of society on the use of radiation: the useful applications of radiation in research, medicine, agriculture and industry are set against its potential hazards

— to be aware of different points of views in society on controversial issues and appreciate the need to respect others’ points of view even in disagreement; and to adopt a scientific attitude when facing controversial issues such as debates on the use of nuclear energy

STS connections

— the use of nuclear power; the complex nature of the effects caused by developments in science and technology on our society

— the moral issue of using various mass destruction weapons in wars

— the political issue of nuclear deterrents

— the roles and responsibilities of scientists and the related ethics in releasing the power of nature as demonstrated in the developments of nuclear power

— stocking and testing of nuclear weapons

— the use of fission reactors and related problems such as radioactive wastes and leakage of radiation

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III. LEARNING AND TEACHING

Learning effectiveness depends on the motivation of students and their prior knowledge, the learning contexts, teaching methods and strategies, and assessment practices. To learn effectively, students should take an active role in science learning processes. Appropriate teaching strategies and assessment practices should be employed with this view in mind.

A. Teacher’s role

Teachers should be well acquainted with the aims and objectives of the curriculum and arrange meaningful learning activities for their fulfilment. They should timely and appropriately employ different learning and teaching approaches, and play the roles of a resource person, facilitator and assessor. Teachers are encouraged to use different strategies such as discussion, practical work and project learning to facilitate students’ learning. The learning process can be enhanced by stimulating students to think, encouraging students to explore and inquire, and giving appropriate guidance and encouragement to students according to individual needs. The followings are some suggestions made in accordance with these observations.

Designing teaching sequence

The topics in the curriculum are listed in a possible teaching sequence. However, different teaching sequences can be adopted to enhance learning. Teachers are encouraged to design teaching sequences for their particular groups of students.

Catering for students’ abilities

In deciding teaching strategies, students’ abilities should be given due consideration, and it is unrealistic to expect every student to achieve the same level of attainment. In this curriculum, the core and extension parts are suggested for different ability groups. Teachers should have the flexibility to devise teaching schemes with appropriate breadth and depth according to the abilities of their own students and to make learning challenging but not too demanding. This can pave the way to enjoyable learning experiences.

Membership of the CDC Ad Hoc Committee on the Revision of S4-5 Physics Curriculum

CONTENTS

Membership of the Joint CDC and HKEA Working Party on the Revision of S4-5 Physics Syllabus

Membership of the CDC Ad Hoc Committee on the Revision of S4-5 Physics Curriculum

Membership of the Joint CDC and HKEA Working Group on the Revision of S4-5 Physics Curriculum

PREAMBLE

I. AIMS AND OBJECTIVES

II. CURRICULUM FRAMEWORK

III. LEARNING AND TEACHING