Review of Consultation Draft for VCE Physics Study Design

Victorian Branch, Education Committee

Web site:

To:Maria James,

Science Manager,

VCAA

19th September 2014

Dear Maria,

Enclosed is the response of the Education Committee of the Australian Institute of Physics (Victorian Branch) to the proposed Physics Study Design.

The document is supported by two appendices:

1. A summary of the Committee's main recommendations as key points for VCAA's consideration,
2. Comments on selected questions from VCAA's questionnaire, that were not addressed in the Committee's response.

Kind regards,

Dan O'Keeffe

on behalf of

Australian Institute of Physics (Victorian Branch) Education Committee

Review of Consultation Draft for VCE Physics Study Design

prepared by the Australian Institute of Physics (Vic Branch) Education Committee

Overview

The Review Panel is to be commended for the quality of the draft document. It is a realistic and legitimate curriculum statement that is worthy of close and detailed analysis.

The draft has achieved many goals.

• It has retained much that is of value in the current course,
• It has inventively solved some of the problems that have emerged in the current course and
• It has re-packaged current content and introduced new content in engaging ways.

However given all that, there is a need for a 'nip and tuck' occasionally throughout the document and in one instance, need for major surgery.

Detailed Studies and Focus Studies

The Detailed Studies in Units 3 & 4 had become de facto core. In Units 1 & 2 they were alive and well. With the necessity of introducing Thermodynamics and possibly some aspects of recent modern physics into the course, the decision to go from three 'options' to only one 'option' was probably inevitable, although regrettable. However, some effort should be put in to devising a way of having focus studies in Year 12, for example a limit of three: Solar technologies, Communication technologies and the Australian Synchrotron, all of which emphasise contemporary scientific and technological initiatives. The old Detailed Studies, Sound and Materials & Structures, should be avoided. It is acknowledged that the AoS1 in Unit 4 would need to be relocated to Year 11 in some form, but such focus studies will enhance the relevance of the subject to students.

The re-formatting of the Detailed Studies as Focus Studies and the introduction of new topics, including some from by-gone decades, is commendable and should revitalise the course.

Some of the Focus Studies read better than others in terms of precision of language, suitability of content, etc, but these matters will be discussed in detail below where each Area of Study is analysed.

There may also be other topics that would make suitable Focus Studies. These should be considered before the study design is approved as it will be some time before there is another review. It may also be useful to build into the study design, the facility to introduce new focus studies without going through a full review process.

Other possible topics include:

• Physics of hearing. For those that enjoy the topic of sound, but prefer the medical context to the musical one.
• History and Philosophy of Science (HPS) topics. There are a few that come to mind including i) Early models of Heat, ii) Newton and Aristotle, iii) Copernicus, Kepler and Galileo and iv) Nature of electricity. The HPS department at the University of Melbourne could offer assistance with the development and resourcing of any of these topics, as they did when similar topics were introduced in the 1980's.
• Communication technologies. The AC to DC focus study is relatively old technology. For example, mobile phone chargers use switch mode transformers. Even digital logic could be brought back in.
• Thermodynamics, e.g. study of split systems and/or refrigeration.

Continued over the page

• Electronics.
• Photonics.
• Topics with a more engineering focus. This is something the study design has lost. Possible topics might include: Geophysics, new materials, nanotechnology, superconductors, etc.

Indeed, the shift to an academic focus in the content has limited the appeal of the subject to those students interested in pursuing engineering careers or TAFE courses. Some effort should be put in to addressing this imbalance.

The view has also been expressed that there is a possibility that some Focus Studies could be an advantage as preparation for Units 3 & 4. However the instances seem only to be i) 'Snell's Law' in Human vision and ii) 'Transformers' in AC to DC. In the case of the Snell's Law, Unit 4, AoS 1 also include the speed ratio, which adds extra depth. It can also be said that the Unit 3 & 4 exam is likely to have only one question on Snell's law, so any benefit is minimal. In the case of the transformer, the same comment could be made, but it can also be said that the original Further electronics Detailed Study did not include the transformer, it was a late addition. So it could arguably be deleted, given that modern chargers use a different technology.

Student-designed Practical Investigations

Practical Investigations have been languishing for a few years under the current study design, which allows a small value for the SAC contribution of the Units 3 & 4 practical investigation.

By giving the Investigation its own Area of Study, as was the case in the early years of the VCE, it gives back legitimacy and status to the task.

The concept of an 'electronic poster' seems to have merit. No doubt there will be much work to fine tune the structure, but the format should allow students to show what they have been investigating without making the task of preparing the report too onerous.

The template is also a valuable innovation. Schools should be encouraged to trial it in 2015. There may be queries about the word limit and whether it should be lower, but students need to have the opportunity to fully explain their purpose and method, analyse their data and interpret their findings, and finally to provide a conclusion and identify possible improvements and further research. Indeed some would argue 1000 words is barely sufficient.

The table also refers to formulating hypotheses and making predictions, which are not normally part of physics investigations. This is commented on below under Key Science Skills.

Teachers do have their concerns about the poster. These are:

• Whether it can convey the richness and depth of the student work and may instead appear as a superficial exercise. The consequence of this is that there may need to be auxiliary material, such as a log book to effectively assess the student's work, increasing teacher workload.
• The constraints of a poster may result in a convergence of assessments with the task not allowing much discrimination.
• The 1000 word limit is too low for what many students currently write in the reports.

It is important that such matters are resolved before the study design is approved and that any poster producing software is fully evaluated.

It should also be noted that the current study design describes the expectations of the investigation in each Unit in reference to the number and nature of the variables. The draft does not.

It is recommended that the following phrases are included in the draft, that is:

• Unit 1: A quantitative investigation involving the collection and analysis of sufficient data points for at least one independent variable will be undertaken. The investigation should be at least partly student designed.
• Unit 2: They design and undertake more complex investigations involving at least one independent, continuous variable, and take increasing responsibility for the design of investigations.
• Unit 4: They design and undertake more complex investigations involving at least two independent variables, with at least one of the independent variables being continuous, and take increasing responsibility for the design of investigations.

Sequence of Content across the Study Design

Some teachers value a curriculum in which concepts are re-visited and then enhanced. Others are content with a sequence of discrete topics. However there is some concern that none of the Areas of Study in Unit 1 are linked to any content in Units 3 and 4. Even the Electricity AoS in Unit 1 is only on DC circuits, while the Unit 3 AoSs are on electrostatics and electrodynamics. This situation may lead to a devaluing of Unit 1.

General Comments

Introduction

Structure

Giving each of the units a title is an attractive touch and may influence teaching practice and textbook writing and so is probably worth retaining. However in practice, in the classroom and in internal school documentation and possibly, even in textbooks, more accessible and 'easier to say' terms are likely to be used. The same also applies to the titles for the Areas of Study.

Units 1-4: Key Science Skills

This section has decided to focus on inquiry based skills and it seems, delete the current references to communication skills. Some thought should be given to retaining these, particularly in the light of the encouragement of the poster format.

The table of skills is quite comprehensive, but given that it seems to be generic across the sciences, it has a flavour that does not fully apply to investigations in physics. The nature of most physics investigations, particularly at secondary level are open ended and exploratory, for example 'How does the impact time and energy loss for a bouncing basketball vary with drop height?'. In this investigation, the student is not interested in testing any hypothesis, they just want to find out what is going on. There is certainly a need to identify dependent and independent variable, to set controls, repeat experiments, etc, but there is little value in speculating on the likely result, that is, 'formulating a testable hypothesis'.

Recommendations:

1.Replace in 'Key science skill' column, the statement in the first row 'select questions, formulate hypotheses and make predictions' with 'formulate research questions'.

2.In the 'VCE Physics Units 1 - 4 skills' column, delete 'formulate hypotheses, questions and predictions'. Also in the next row delete 'determine appropriate type of investigation' as this is an artificial task of little consequence for physics investigations.

3.Further down in the 'VCE Physics Units 1 - 4 skills' column, the dot point 'use descriptive statistics .....' seems to contain methods more common in biology and psychology. Physics students normally would not use some of these methods, such as bar charts and frequency polygons and more particularly, would find the equations of lines of best fit or do log - log graphs of their data. So this dot point should be more specific to physics.

On a related matter, all of the Areas of Study and Focus studies include a heading of 'Key knowledge'. The current title emphasises the content to learnt and ignores the important starting verbs. The words 'explain, 'compare', 'calculate', etc carry weight and they should be brought to the attention of the reader's eye.

Two possible solutions are suggested:

• below each Knowledge sub-heading, insert the sentence 'to achieve this outcome, the student should be able to' , or
• change the outcome statement to read 'To achieve this outcome, the student will draw on key knowledge as elaborated below and the relevant key skills on pages 9 and 10'.

It should also be noted the chapter on 'Skills' in the current study design addresses a broad range of skills, whereas the equivalent chapter in the proposed study design only considers experimental skills. Either of these proposed changes corrects this imbalance.

Unit 1: How can the unseen be explained?

Area of Study 1: Can the Universe be explained?

This Area is well intentioned in trying to bring together most of the physics terms that feature in news stories in recent years. However they are brought together in a manner that is not likely to engage students or teachers. Important physics concepts are brought together seemingly without any appreciation of the depth of the background information necessary to give substance to the concepts.

It is almost as if, the expectation is that students are expected to recite the content without any level of understanding. This can only lead to confusion among students, frustration on the part of teachers and possibly negative impacts on the perception of the subject.

Regrettably it seems that there is little that can be salvaged from this Area of Study and a new one would need to be written from scratch. Three possibilities are:

1.A new Area of Study called 'What is holding the nucleus together?

Key knowledge to include:

• Radioactive decay
• half-life
• Nuclear transformations, including beta decay and neutron to proton
• Reasons for proposing two new forces: strong and weak nuclear forces
• prediction and discovery of neutrino and the positron
• prediction, discovery and decay of mesons to explain nuclear forces
• prediction and discovery of quarks as components of mesons, protons and neutrons

This proposal has some of the elements of 'The Universe' Area of Study, but gives structure, links to students' current knowledge and provides some practical opportunities. This proposed Area of Study could lead on to, either a Unit 4 Area of Study or even a Unit 2 Focus Study, covering such aspects as conservation laws and symmetries, which can be described and analysed using simplified reaction diagrams. Examples of this approach already exist, in particular in the Dutch physics curriculum.

2.Move 'How can waves explain the behaviour of light' from Unit 4 to Unit 1.

This Area of Study is predominately about Year 11 level content and would sit well in Unit 1.

3.A third possibility is to adapt the second possibility above to give it a focus more reflective on the current AoS 'The Universe'. It could have the nominal title 'How does light help explain the universe?' Key Knowledge could include:

• describe transverse waves in terms of amplitude, wavelength, period and frequency
• calculate wavelength, frequency, period and speed of travel of light waves, v= fλ = λ/T
• investigate and analyse the behaviour of light using ray diagrams including

– reflection, i= r

– refraction, Snell’s Law

• describe image formation in a concave mirror and a convex lens using ray diagrams
• compare the optics of reflecting and refracting telescopes using applets
• identify visible light as a particular region of the spectrum of electromagnetic radiation and that all light travels at the speed of light in a vacuum, c
• explain colour dispersion in prisms and lenses in terms of refraction of the components of white light as they pass from one medium to another.
• describe the spectra of different elements in terms of absorption lines, which are unique to each element and appear shifted in the spectra of star light.
• describe the doppler effect and calculate the red shift of star light, z,

using 1 + z = observed / emitted

• explain Hubble's observations as evidence for an expanding universe.
• explain Schmidt's observations as evidence for an accelerating universe.
• explain diffraction as the directional spread of various ... changing the wavelength and gap width
• explain how atmospheric distortion, dispersion and diffraction limit the performance of telescopes and describe some solutions such as adaptive optics

Either of possibility 2 or 3 would allow possibility 1 to become an Area of Study in Unit 4 with the inclusion of additional content on conservation laws and symmetries as referred to above.

Area of Study 2: How can thermal effects be explained?

This is a well written, imaginative topic. The choice of contexts with three options is an encouraging sign. Although textbook publishers would be in an awkward position and may need to pick one or two if three are ultimately available. For this reason, it may be wiser to drop the car context, particularly as the internal combustion engine is on the way out. The saving grace is that the study design says '... one or more of the three options ...' and 'and/or Earth'. So, many teachers may merge either of the first two with the third option.

The main concern is with the spread of content in the key knowledge and the extent to which all the content can be covered in any of the options. For example a key section of the key knowledge is 'Thermodynamics and global warming'. For the first two options of the car and the home, there is no obvious link. The last dashed point in the first two options starting with 'Can thermodynamic principles related to ... ' seems an artificial add-on so that all the key knowledge can appear to be covered in one option.

This suggests an alternative solution. Link Option 1 and 2 to the 'Thermodynamic principles' section of Key knowledge and rename Option 3 as the context for the 'Thermodynamics and global warming' section. This does not get over the text book problem, but it seems a neater solution for the study design.

Option 3: Thermodynamics and earth

The second dashed point refers to the Carnot cycle. There seems to be no obvious link between the Carnot cycle and the dot points in the Key knowledge. The Carnot cycle applies to weather systems such as cyclones and convection cycles beneath the earth's crust, rather than climate change per se.

Key knowledge

Thermodynamic principles

The three dot points on kinetic energy under 'Thermodynamic principles' seem a strange inclusion. They seem to be about Gas laws and don't seem to relate to other content or even the three options. It is seems like equations for equations' sake. Most students will have little prior exposure to kinetic energy, so introducing a quantitative definition devoid of its mechanical context is problematical. Students should have a qualitative understanding of associating kinetic energy with the energy of movement, so the first of the three dot points is acceptable, but the other two don't seem to have much relevance. A much more relevant concept to introduce would be that of 'internal energy'. This actually relates to the first dot point on the First Law of Thermodynamics, which can easily be skipped over as one reads the document. This first dot point needs some elaboration as it can be interpreted with varying levels of depth. It should also be relocated in the following suggested order: