Table of contents

Westminster School, London, UK

A few weeks ago David Thomson, J J Thomson's grandson, presented a Friday evening discourse at the Royal Institution. In it he traced the development of JJT's life from his early studies at Owen's College in Manchester, on to Trinity College Cambridge, his work under Rayleigh at the Cavendish, and his succession as Professor of Experimental Physics in 1884 (a post he passed on to Rutherford in 1919). These were years of heroic discoveries that shaped 20th century physics. Looking around the lecture theatre at all the bow-ties and dinner jackets, it must have been rather similar on 30 April 1897 when JJT delivered his famous discourse on 'Cathode Rays' in which he cautiously but confidently announced that his own results together with those of other experimenters (Lenard in particular):

<BLOCKQUOTE> `....seem to favour the hypothesis that the carriers of the charges are smaller than the atoms of hydrogen.' </BLOCKQUOTE>

In this issue articles by Leif Gerward and Christopher Cousins, and by Isobel Falconer explore the historical and philosophical context of that discovery. The sound-bites to history in many A-level courses have JJT as both the hero who single-handedly discovered the electron and the rather naive Victorian scientist who thought the atom was a plum pudding. It is valuable to see how Thomson's work pulled the threads of many experiments together and to realize that he may have been first to the post because of a difference in the philosophical approach to cathode rays in Britain compared to Europe. Experimental data must always be interpreted, and divergent philosophies can lead to quite different conclusions.

The electron was, of course, the first subatomic particle to be identified. Christine Sutton's article looks at how 20th century discoveries reveal Nature's mysterious habit of repeating successful patterns---electrons for example have very close relations, the muon and the tau---but why? Perhaps the answer will come from the theoreticians. One of the greatest of these was Paul Dirac, a marvellously reticent man with an eye for mathematical beauty. David Miller, one of the winners of William Waldegrave's 'Higgs Challenge' in 1993, shows how Dirac constructed his famous equation, and how it describes the behaviour of the electron and its neutrino and led to the prediction of antimatter and the explanation of spin. He draws an interesting parallel between Dirac's negative energy electrons and the contemporary development of solid state physics.

G P Thomson, JJ's son, also got in on the act: father got the Nobel Prize (1906) for showing the electron is a particle and son (1937) won it for showing it also behaves like a wave! This has had a profound impact both on the interpretation and experimental testing of quantum theory and in the way we use electrons. Electron waves are essential to understand solid state physics and wave-like properties are fundamental to the behaviour of many electronic devices. But it is not just in physics and electronics that the electron has been revolutionary, and John Squire's article reviews the use of the electron microscope in biology.

Having crossed the border into biology (as so many physicists have done this century) it should be pointed out that electron physics also caused a paradigm shift in chemistry. Electronic structure made the Periodic Table comprehensible and led to a theory of bonding that accounts for the mechanical, electrical and optical properties of many materials. This is described in Peter Hughes's article. Which brings me back to JJT and those sound-bites, and the Royal Institution for that matter....

On 10 March 1905 JJT gave another of his Friday Evening Discourses. This one was called 'The Structure of the Atom'. In it he developed a model suggested by Lord Kelvin, in which negative corpuscles arrange themselves in a stable configuration within a sphere of positively charged fluid. This is the infamous `plum pudding'. There is not room to go into detail here, but he showed mathematically and using a 2D magnetic model that the electrons would arrange themselves in a series of shells which he identified with the periods in the Periodic Table and linked to reactivity. He discussed electronegativity and showed how it would increase along each period (as it does). He suggested transmutation of the elements by a rearrangement of the positive fluid and even considered electrostatic conditions which might result in fission or fusion (remember, this is long before the alpha scattering experiments of Geiger and Marsden). Even covalent and ionic bonding and crystalline structures were included, with atomic valence directions corresponding to lines of symmetry in the electron arrangement inside the atom. It is a shame that the `plum pudding model' gets such shabby treatment, and perhaps a comment on the distorted view of the history of physics we pass on to our students by ignoring the context and background to important discoveries.

The Education Group's Annual Conference, 27 - 29 March 1997

This year the Annual Conference of the IOP Education Group featured as part of the IOP's Annual Congress, and attracted some 80 participants. The talks and lectures that were the formal parts of the Education Conference were as stimulating as ever. This year the programme allowed plenty of time for discussion in working groups about perennially topical issues such as women in physics, the teaching of new physics, the use of the Internet and the vexing question of physics students' competence or otherwise at mathematics. All this was in the context of the IoP's major curriculum initiative on 16 - 19 physics.

Joining in with the Annual Congress had its drawbacks, however; the informal chats that are often as valuable as formal inputs about physics education were rare or non-existent - members were accommodated in different residences, social areas were bleak and TV-ridden and meals diluted by the presence of physicists from other more esoteric groups so that conversations tended to be about the weather (bleak) or the Hale - Bopp comet.

The theme of the conference was effective teaching and learning for the future, building upon the previous two conferences and linking with the Institute's post-16 curriculum initiative starting in April 1997. The Keynote Talk was by Ken Dobson, on The management of change in education, who moderated his general enthusiasm for curriculum change with warnings about developing a curriculum at a time when practitioners feel less than ecstatic about the current nationally directed top-down dumping model of curriculum change. He pleaded for more involvement of practitioners, and compared natural diffusion with forced change, modelling them as organic and plate-tectonic, the first allowing for growth monitored and modified by feedback, the second with increasing strain leading to catastrophic modifications. He illustrated the jargon with examples from the National Curriculum, A-level subject cores and the Suffolk Science Development.

Working groups

Working groups were designed to follow up the talks, and on the first afternoon members could choose between Bob Kibble's Total Quality Management (or what makes a good physics teacher!), Richard Brawn's Mythologies and experience (or why girls don't like physics) and Ian Lawrence's Learning with IT in the laboratory. I'd guess that the most significant of these for curriculum development was Richard Brawn's account of research he had done on girls' attitudes to physics. In short, the National Curriculum has increased girls' exposure to physics, but this has in general simply served to confirm their opinions that it is hard, delivered by teachers lacking in empathy, using overformal language and hurrying too quickly through too many not very relevant ideas. Quite scathing, in fact. Even girls who did well at physics felt that it wasn't something to take further: there was no scope for imagination, so that physics appeared as a 'top-layer, finished product'. The message was that developing a brilliant post-16 curriculum may be a waste of effort if things don't change pre-16.

Sobered by all this we then had a slightly more encouraging talk by Patricia Murphy in a joint meeting with the Women in Physics Group. She gave data showing that girls were increasingly doing better than boys at sciences in the GCSE - as in all other subjects. Early socialization accentuated what might be natural differences between the sexes. Boys get better at measuring because they do more of this outside school than girls do, boys construct, role-play at being superheroes and dominate. Girls collate, talk, read, look for help from each other, socialize, gossip and are caring. Which strategy produces the best learners? Or are both differently valuable? There was a wealth of detail, but again the message was coming through - listen to the pupils as individuals, design courses which build on strengths to ameliorate weaknesses.

Key skills

The first talk on Day 2 was by the ebullient John Lewis, who talked about the Key Skills course he was instrumental in developing. The course is now very popular and leads to certification by the Oxford and Cambridge Examination Board, but its main purpose is education rather than certification, and provides a huge range of contexts and activities in which and through which students can improve their abilities to communicate, learn more effectively, manage their affairs and generally become more independent as learners and incipient adults. At present this is an 'add-on' type of course taken in minority time, but there are valuable lessons to be learned from it in making 'key skills' an essential strand in physics courses at all levels.

The morning's working groups looked at novel aspects of curriculum content: the TRUMP (Teaching Resources Unit for Modern Physics: details from Dr E Swinbank, Science Education Group, University of York, York YO1 5DD, UK. See also Phys. Educ. 32 (1997) 40 - 5.) Astrophysics Project; Quantum Physics (can we teach it? can they learn it?) and Physics through a space probe. The first produced tantalizing glimpses of materials under development for making more active the learning in the increasingly popular astrophysics options at A-level. These were as attractive and stimulating as the same group's Particle Physics pack. Materials are available from summer 1997.

There are strong voices amongst professional physicists for school physics to get more up-to-date, especially in that most significant of 20th century physics ideas, the quantum. Bob Lambourne (Open University and the FLAP project) outlined the opportunities and problems of teaching quantum physics at school level and led the subsequent discussion. He was careful to make the distinction between quantum physics and quantum mechanics, and there seems plenty of scope for interesting work leading to the vital reconceiving of physics that seems to be necessary at pre-university level. Another strand in a new view of teaching physics was Chris Butlin's talk on how a specific, well-chosen context can be used to develop a wide range of knowledge, understanding and skills. His 'space probe' could be used not only to illustrate the usefulness of the physics but also gives scope for discussing the social and economic factors related to space exploration and off-world travel.

What is happening post-16 - and what might happen

In the afternoon The IOP's Education Manager for Schools and Colleges, Catherine Wilson, gave us the latest news in the rapidly changing world of centralized curriculum control, leading us gently and without excessive rancour through the tortuous paths of subject cores, SCAA rules about linear and modular A-levels and the new AS-level. Catherine gave details of some of the hastily produced new A and AS syllabuses (first examination 1998!) and the disappointments of the GNVQ alternatives. Then we were cheered up by 20 refreshing minutes from Jon Ogborn, just appointed as Director of the IOP's 16 - 19 Project. So maybe all things shall be well, all manner of things shall be well....

The workshops that followed varied from the technical ( Use of spreadsheets) to the inspirational (brainstorming Physics 16 - 19) via the stratospheric ( Learning via the Internet). The Internet has been proposed as a system for a complete revolution in the way students can learn. Martin King gave sound advice on what is currently possible, illustrated by the extensive work he has done on this at Verulam School. However, it seems unlikely that the bandwidth currently exists for a serious increase in Net use, even without every schoolchild making full use of an e-mail address.

Mathematics in physics

The last morning was devoted to mathematics. Peter Gill of the Mathematics Department at King's College London described his teaching of what he is not allowed to call remedial mathematics to first-year chemistry and engineering undergraduates, and his research into changes in students' competence over the years. His intriguing discoveries will be described in more detail at the Education Group's 16 - 19 Day Conference (15 November). Maybe we shall also find out something about what we should do about it. A follow-up workshop elicited a variety of strategies that teachers use to develop their A-level students' mathematical skills: plenty of graphs and algebraic manipulation, but don't rush too quickly to the formulae, be upfront and confess that maths in physics is different from maths in maths and tells a different story, arrange for challenging activities for everybody (especially the ones who are good at maths). Above all, SELL IT! There was general consensus that maths is too important to be left to the mathematicians.

All in all a stimulating three days, and as far as future physics education is concerned a clear win for the optimists over the pessimists. But perhaps the pessimists were somewhere else.

Ken Dobson

The annual meeting organized by the Education Group of the IOP for those concerned with the training of teachers to teach physics was held on 10 March 1997. Pressure of time rather than unwillingness to take part led to a group of only ten, out of a possible 40, tutors meeting with John Howson, Chief Professional Adviser (Teacher Supply) at the TTA (Teacher Training Agency). He brought with him a set of statistics, some of which are shown below, on the current applications for entry into PGCE courses for physics. The discussion which follows represents those present and not necessarily the policy of the TTA.

The DfEE is responsible for giving the TTA its target numbers for each subject and it is the TTA's job to allocate target numbers to all training institutions. In shortage subjects the TTA is charged with encouraging more applicants in whatever ways are appropriate, such as the four-page advertising feature in Physics World [1]. One of the major problems is that the TTA target numbers are for science and not physics. Training Institutions need to meet their target numbers because of costs, and the surest way to do this is to fill up courses with early applications from good students who can be relied on to register at the beginning of the course. This means that courses are predominantly filled with biologists. One large northern university currently has 50 science students studying for the PGCE and no physics students.

The publication of science numbers rather than physics numbers leads to complacency while the real crisis in physics numbers goes unnoticed. Even Physics World [2] managed to write in February 1997 `...the TTA is doing its best to recruit more science teachers. Applications were up a third last year... Meanwhile training courses for physics teachers are on the brink of amalgamation and closure because they are no longer financially viable. The threat to the future of physics and engineering is obvious.

Figure 1 shows the intake for PGCE science students alongside the target numbers for the past 14 years. The target numbers are set to level off from 1997. Normal retirements as well as early retirements from an aging profession and an increasing school population with possibly more students taking the new AS-level may show the levelling-off of target numbers to be unwise.

Figure 1. PGCE target numbers and intake numbers for science.

Figure 2. PGCE science applications at weekly intervals (source: GTTR weekly data).

Figure 2 shows the applications for science PGCE courses at weekly intervals over a period of four years, each year having fewer applications than the preceding one. A breakdown of numbers for the separate sciences for week 21 (first week of March 1997) of the application round reveals:

The 1996 figures are in brackets. It is predicted that 68% of the total scientists applying this year will register at the beginning of the course, with the possibility for physics being lower.

Table 1 shows the number of unfilled places by region for 1996 (note the revised Open University target).

Table 1. PGCE unfilled places on ITT courses for 1996/7.

Table 2. Vacancy rate for classroom teachers in secondary schools by subject as a percentage of teachers in post in 1996.

Table 2 is interesting because despite the crisis in the low numbers going into training there does not appear to be a similar crisis in schools. The vacancy rate is small, if variable, in schools. Could this be because vacancies are being suppressed as class sizes rise and curriculum choice is curtailed or that 'returners' to the profession are filling the gaps? The TTA is currently surveying the qualifications of teachers in school, and when it is complete it will then, perhaps, be known exactly who is teaching what to whom.

The discussion that followed the presentation was surprising in its unanimity, considering that those present taught on a variety of training courses and one was even able to comment on the situation in France. The main problem for teacher trainers is the time available to do a good job. There is an assumption that when graduates begin a PGCE course they fully understand the subject which they are to teach. Not only does a bright, new shiny physics degree not guarantee that a physics graduate will be able to understand and translate the physics that s/he has studied into school lessons but it certainly does not offer an understanding of the other sciences that the trainee needs to teach. How many potential physics teachers do not pursue a PGCE course because they would rather teach physics and mathematics? Many physics students, when they have finished their training, seek out the schools which will give them a large percentage of time teaching physics. The time available in higher education institutions for all PGCE science teaching is less than 30 days; 20 days for physics is more than most institutions have. Mentors in school have time constraints too, especially when the trainee needs to be taught what they have to teach.

Many suggestions were put forward for improving the situation and only time will tell if anyone is listening.

Brenda M Jennison

References

[1] Physics World 10 no 2, February 1997

[2] Editorial in Physics World 10 no 2, February 1997

One of the reasons scientific education has lost ground is that the teaching in these subjects has not been renewed at a sufficient pace. What is taught at school is very often far from the research front. The project that we have worked out aims to increase the interest in and understanding of modern science, particularly particle physics. One of the main components is a multimedia program about the Standard Model of Microcosm combined with more traditional teaching methods like seminars and problem-solving sessions. Another important component is the images of particle collisions at the Large Electron Positron collider at CERN [1] outside Geneva. The heavy Z° particle is produced in high energy collisions between an electron and its antiparticle, the positron. The Z° is one of the mediators of the so-called weak force, acting at very short distances in the interior of matter. The project aims at studying the production and decay of this particle and learning about the most fundamental parts of the interior of matter.

The multimedia Standard Model program

We have produced a multimedia program enabling the user to explore the Standard Model of modern particle physics. The user learns about the inner structure of matter, the fundamental forces in nature as well as the tools used by particle physicists. The program is a journey, controlled by the user, through a tree structure which becomes more advanced by depth, starting out on the most elementary level. Questions and answers test and verify the user's knowledge before and after running the Standard Model of Microcosm (SMM) program.

Computing tools

The general layout and tree structure of SMM was created with Authorware^TM Professional [2], a flow-chart oriented programming tool, using icons for various functions. It requires 2.3 Mb RAM and 10 Mb disk space. The SMM Authorware skeleton requires 4 Mb RAM and 6 Mb disk space. SMM is a tree structure of 115 screens. An example of a screen is shown in detail in figure 1. Several movie sequences and sound files are included in SMM. The movies demonstrate the experimental exploration of the interior of matter and the theoretical description of the processes.

Figure 1.

Strata Studio Pro^TM [3] was used to create graphics images and Quicktime movies. Studio Pro is an object-oriented graphics tool for three-dimensional effects. It requires 5 Mb RAM and the files that we created are usually 200--700 kb large. To create a graphics image, a wire frame model of the object is created. Shapes, colours and textures can be chosen by the user. When the wire frame model is finished, a rendering is called to produce the final image. We mainly used the so-called Gouraud shading to obtain three-dimensional effects without casting shadows. The most commonly used rendering technique is ray-tracing, but we wanted to avoid shadows from objects like the particles in the interior of matter. We used Studio Pro to create all the movies. The movies occupy a total of 6 Mb of disk space.

Versions of SMM exist for both Macintosh and PC. It requires 13 Mb of disk space and 4 Mb memory including 370 kb fonts, a 16 kb Quicktime player and a 430 kb RunAPM. There is a small demo version available on the Internet [4]. A smaller, less detailed version of SMM is available on a 1.44 Mb diskette. This version is also available on the Internet [5]. A MacIntosh or a PC and the Shockwave^TM plugin are needed to explore this version of SMM.

Exploration of high energy particle collisions

At the Department of Physics (Fysikum), Stockholm University, we have been engaged in establishing a Science Laboratory aimed at 15 - 18 year-old students. This laboratory focuses on modern experimental set-ups which illustrate basic physical principles. However, the Science Laboratory also acts as an umbrella organization for various outreaching activities. In several of these, the Standard Model program package has proven to be very useful.

The first project used the Standard Model multimedia program and images of particle interactions registered by DELPHI [6]. DELPHI is an international particle physics experiment at CERN. This modern physics experiment, with which the innermost building blocks of matter are explored, was introduced to 17 year-old students at Blackeberg Gymnasium in Stockholm. The project work took place both at the school and at Fysikum. Approximately 20 hours were devoted to this study of quarks and leptons during a two-month period. More details can be found at the Internet addresses below.

L Bergström, K E Johansson and T G M Malmgren

References on the Internet

[1] http://www.cern.ch/

[2] http://www.macromedia.com/software/authorware

[3] http://www.strata3d.com/html/strata_studiopro.html

[4] http://www.physto.se/~tordm/stdmod/stdmod.html

[5] http://www.physto.se/~tordm/poster.html

[6] http://www.cern.ch/Delphi/Welcome.html

[7] http://vanh.physto.se/~hoc

Some of the latest developments in particle physics were explored by hundreds of UK young people at the first National Particle Physics Masterclass which took place on 11 - 23 April 1997. This was organized by the High Energy Particle Physics Group of The Institute of Physics, in conjunction with several university physics departments.

Sixth-formers studying physics, along with their teachers, were invited to spend a day experiencing the excitement of particle physics at first hand, with a mix of talks and PC-based practical sessions. The sessions gave hands-on experience of the type of interactive graphical display programs that are used at CERN in Geneva, and students were able to study real particle collisions from the Large Electron Positron Collider (LEP), including collisions from the run during which LEP operated at nearly twice its previous energy. Other practical activities saw students making their own measurements of particle tracks, using software specially designed for schools, and making the most of the World Wide Web in studies of particle physics.

The universities taking part were Lancaster, Manchester, Durham, Liverpool, Imperial College, Swansea and Oxford. More such classes, at a wider range of universities, are planned for next year.

Any students who enjoyed the Masterclass could keep a constant reminder of their involvement by downloading a screensaver of Schrödinger's cat courtesy of PPARC (the Particle Physics and Astronomy Research Council)! The screensaver is aimed at 11 - 16 year-olds and is free by opening the box at http://www.pparc.ac.uk/freebies/saver.html. The PPARC site reflects the range of activities supported by the research council throughout the community, including providing schools with new materials relevant to the curriculum.

A second competition for educational multimedia software for schools is being organized by the European Commission, following the pilot action undertaken in 1996. The aims are to encourage users of learning aids to design novel multimedia products for use in teaching; to stimulate the creativity of young people in Europe by designing products which might be developed and distributed at European level; and lastly to raise awareness of students and teachers to the importance of new information technologies in schools.

There will be separate awards in two categories: firstly for students in primary and secondary education (category A); and secondly for students in higher education establishments, including multimedia training organizations (category B). Projects may be submitted by groups or individuals, with the appropriate accompanying software, in PC or Mac format. Any official European Union language can be used, as the projects will be evaluated at national level by national committees appointed for the purpose. Each member state will shortlist five projects in each category to go forward to the European competition, and the prizes will be awarded in November. Deadline for project submission is 30 September 1997; further details may be obtained from European Commission DG XXII - Education, Training and Youth, Mr Jimmy Jamar, 200 rue de la Loi, B-1049 Brussels (tel: +32-2-2952082, fax: +32-2-2967012, email: joseph.jamar@dg22.cec.be).

Two instantly recognizable icons of modern physical sciences are Einstein and Marie Curie - the former for the theory of relativity and the latter for the discovery of radium and polonium. Indeed, the term radioactivity was introduced by Marie Curie (and it was she who strongly recommended Einstein for a major post in Zurich).

The 1998 centenary of the discovery of radium by the Curies will be celebrated - slightly in advance - at a meeting to be held at the Royal Society, London, on 8 October 1997. Distinguished speakers will discuss the work of Marie Curie and will give demonstration lectures on developments and applications in the field of radioactivity over the last 100 years. Sponsored by the Polish Cultural Institute and King's College, London, and supported by the Institute of Physics, the meeting will be aimed at sixth-formers and college students and will be concerned with scientific, medical and environmental, as well as historical aspects of the Curie legacy.

Applications (from teachers on behalf of students) to attend the meeting should be sent to the Event Secretary, Polish Cultural Institute, 34 Portland Place, London W1N 4HQ (tel: 0171 636 6032, fax: 0171 637 2190, email: pic-lond@pcidir.demon.co.uk). Admission will be (free) by ticket only, and applications will be handled on a first come/first served basis.

Future events for science teachers which will promote the profession and raise awareness of the dedication of teachers over the years are currently in preparation. The first of these is a Festival to be held in 2001 to mark the centenary of the formation of the Association of Public School Science Masters (precursor of the UK's Association for Science Education). The festival will take the form of an exhibition with related events and publications focusing on the lives and work of science teachers. As there has been a heavy emphasis on the curriculum in recent years, this event is in part an attempt to refocus attention on the contributions of teachers themselves.

Besides the proposed exhibition of books, equipment, photographs and apparatus (plus an accompanying catalogue which may be in the form of a CD-ROM) there will be talks and symposia, publications and possibly a book and TV/radio documentaries. The whole event will be inaugurated at the ASE's annual meeting in January 2001, and during the preparation for the festival an opportunity will be taken to establish a National Archive on the Teaching of Science. Interested teachers are now being encouraged to participate in the plans for the festival, and they should contact Mick Nott at the Centre for Science Education, Sheffield Hallam University, Sheffield S10 2FL (email: m.nott@shu.ac.uk) for further details or addition to the mailing list.

`School Links International 1999' is a celebration of school science across the world, as part of the Science 2000+ project being coordinated by Unesco, ICASE and the ASE. Groups of students from different cultures throughout the world will be working together on the same project-sharing ideas, and at the same time learning about each other as well as their science. Schools can take part by making use of a link they already have, after finding their own link, or by using the project to find a link for them. All participants will receive certificates, whilst the best group will be part of an international ceremony. Anyone wishing to join the project or just find out more should write to Caroline McGrath, The Science Centre, Runnymede Centre, Chertsey Road, Addlestone, Weybridge KT15 2EP.

Shortlisted for the 1997 Rhône-Poulenc Science book prizes were two physics-related titles. Fire in the Mind: Science, Faith and the Search for Order by George Johnson (Viking £18, Penguin pbk £8.99) and Longitude by Dava Sobel (Fourth Estate £12) were on the list announced back in May, from which the winner was due to be selected in June.

The prizes were established almost a decade ago to encourage the writing, publishing and sale of popular science books for nonspecialist readers, and are organized jointly by COPUS and the Science Museum in London. Among this year's judges were Deborah Cohen of the BBC Radio Science Unit and Dr Christine Sutton of the Physics Department at Oxford University. Authors of both the General and the Junior Prizes receive the sum of £10000 each, and the increasing attention experienced by the Science Book prizes reflects the public's growing interest in popular science.

Individuals with a science or engineering background who would like to encourage an understanding of science and technology within their own communities may now receive funding from the Royal Society and British Association Millennium awards scheme.

Awards range between £1000 and £10 000 and can cover such activities as training, resources, materials and travel. To be considered for an award, applicants should have an innovative plan and a partnership with a community group (the latter could be a local museum, school, pub, leisure or community centre or even a newspaper, television or radio station). Projects might involve skills training, creating interactive displays, setting up science trails, imaginative ways of conveying the science behind the news, and even possible secondments.

There are four rounds for awards, with closing dates for application forms as follows: 30 June and 31 December (both in 1997) and 30 June and 31 December (both in 1998). More information can be obtained from Jane Mole, British Association, 23 Savile Row, London W1X 2NB (tel: 0171 973 3069 or email: ba.talk.science@mcr1.poptel.org.uk). It should be noted, however, that awards will not be made to: (a) enable the purchase of technology for writing books to popularize science/technology; (b) fund research into the public understanding of science/technology; (c) continue support for projects on a long-term basis; (d) develop curricula or projects in formal education; (e) fund running costs of any establishments.

Two recent appointments at The Institute of Physics in London continue the Institute's strategy of pushing forward with educational support for schools and colleges.

The first new arrival at Portland Place was Professor Jon Ogborn, who was appointed Project Director in charge of the `revolutionary' rethink of the 16--19 physics curriculum. Professor Ogborn was formerly co-director of the Nuffield A-level Physics project, and subsequently Professor of Science Education at the University of London Institute of Education. Over the next three years he will be leading discussions between schools, universities and industry aimed at reaching a new consensus on the most desirable and appropriate structure of physics courses for 16--19 year-olds. The Institute is convinced that the curriculum must change through a thorough update and increased appeal to students, especially girls. The resulting courses must therefore provide what universities and employers need (solid competence in essentials, including mathematics) but additionally excite and enthuse a new generation of students.

Second newcomer to the Education Department is Mary Wood, who has taken the role of Coordinator: Education Support (Schools and Colleges). At the start of her career Mary was a microwave engineer with GEC Marconi Avionics, but after a career break she moved into teaching. At the Institute Mary will be developing links between school physics and the world of work, careers advisory work, INSET for teachers and new curriculum materials.

We look forward to hearing more from both staff members in the pages of Physics Education in the future.

Liverpool will host the 1998 Annual meeting of the Association for Science Education, which is being advertised as the UK's largest training conference for science teachers, lecturers and technicians. The dates are 8--10 January 1998, and there will be the customary blend of talks and workshops, courses, science lectures, exhibitions, social events and visits. Accommodation will be centred on the University of Liverpool, and full details of the conference are available from the ASE, College Lane, Hatfield, Herts AL10 9AA (tel: 01707 267411, fax: 01707 266532, email: ase@asehq.telme.com).

All the Letters to the Editor in this issue are in the same PostScript or PDF file.

Contents

Joining capacitors R Bridges King Edward's School, Birmingham B15 2UA, UK

Enjoying Physics John Bausor 5 Longcrofte Road, Edgware, Middlesex HA8 6RR, UK

The disadvantages of success M L Cooper Newham College of Further Education, London

The search for the true nature of electricity led to the discovery of the electron and the proof that it is a constituent of all atoms. These achievements gave scientists the first definite line of attack on the constitution of atoms and on the structure of matter.

One experiment, more than any other, is often associated with the `discovery of the electron' in 1897. This is J J Thomson's determination of the mass to charge ratio (m/e) of cathode rays by deflecting them in magnetic and electric fields. Yet this experiment was performed two months after Thomson first announced that cathode rays were very small, negatively charged particles. So why was it important? I look at Thomson's route to, and conduct of, the experiment, and then at how his ideas were received.

Is the electron so important? The author presents an irreverent view.

When Thomson discovered something far smaller than the atom, he laid the foundations of particle physics---the study of the elementary particles of matter and the forces that act upon them. He also discovered the first member of one of the main 'families' of particles: the leptons.

Dirac devised the quantum theory of the electron itself, which required him to generalize Schrödinger's famous equation to cover relativistic motion. He interpreted the resulting equation as showing that an antiparticle to the electron must exist.

One hundred years after their discovery, the wave characteristics of electrons are being exploited routinely in electron microscopes to visualize atoms and molecules. With modern computing methods, molecular structure within biological tissues can be determined in three dimensions by image processing of electron micrographs.

Electrons are the key to the ways in which atoms interact. The nature of the chemical bond is described here, with emphasis on the role of electrons in the four main types of bond: intermolecular, interionic, covalent and metallic.

The notion of internal energy at a level appropriate for students of the Introductory Physics Course (IPC) is examined. The methodology proposed offers a general frame for analysing practically any physical system or process in a system of particles, from thermal phenomena and phase transitions to chemical and nuclear reactions, including processes involving elementary particles. The role of interactions among particles in a system is emphasized. The notion of statistical equilibrium of a system is discussed in this context. Finally, two structure factors are introduced to show the relation between the kinetic, interaction and particle energies of a system in maintaining stable structures.

The physicist's choice of B in electromagnetics teaching is inconsistent with the engineer's preference for H. In part 1 the author uses an example to show how the use of B can cause confusion, and in part 2 the problem is resolved and it is shown how the use of the magnetic vector potential A could make the picture clearer. Part 3 shows how the use of A can be extended to several common electromagnetic situations.

When certain rotating bodies are viewed in artificial light a stroboscopic efect can be observed that would not be seen in daylight. A simple analysis of this effect is presented here together with an experiment using a bicycle and a tachometer that allows students to determine the frequency of the mains electricity powering the light.

A simple toy is shown to have many interesting uses in the school physics laboratory.

It is shown here how a torsion Coulomb's apparatus described previously can be used to find , the permittivity of a vacuum, to an accuracy of about 15%.

Continuing the theme of this issue on J J Thomson's electron, this interview has been constructed from the references given at the end.

The opening of the preface states that 'this is a reference book, a review book, and a book that contains some highly biased advice'. This neatly describes a somewhat idiosyncratic book directed at physics teachers, who as far as the UK is concerned would be teaching first- or second-year degree students. The contents of the book have largely arisen out of many years of editing by the authors of The Physics Teacher.

The opening chapter is titled 'Fatherly Advice' and contains general but rather brief ideas for teaching physics, particularly regarding the use of demonstrations and laboratory work. The next two chapters introduce error (uncertainty) analysis and dimensions and units but again are limited in scope such that one wonders how useful the material is for the already practising lecturer. From here on the chapters cover mainly classical physics in a style directed at the teacher. The emphasis is on arguments and mathematical derivations concerning such topics as gravitation and relativity, dynamics, work, energy and thermodynamics, fluids, vibrations and wave transmission, and electrostatics through to electromagnetism. The very last chapter, called 'Microstructure', does contain modern physics, although it starts with the identification of the electron in 1897. It discusses spin and quantum numbers, moves on to the uncertainty principle and atomic structure and ends up with the quark model.

A total coverage of each of the topics is not attempted. There are numerous pen-and-ink style pictures which give the pages a pleasing appearance and are of about the right complexity. The text uses vectors and calculus, yet the mathematical detail is rather restricted for university physics this side of the Atlantic. There are numerous references and suggested further reading but the majority of these are taken from The Physics Teacher. Overall the book contains some unusual views of aspects of physics. Examples one might quote are wobble rotations by asymmetrical rotators, applications of Fermat's principle and production of sound by musical instruments. It makes a very nice book for the library shelf where one can seek out a slightly different insight into a topic. But I am not sure that it will be used generally as a reference book by teachers.

The Edinburgh Science Festival is in its ninth year and claims to be the world's largest Science Festival. This volume, produced for this year's Festival and drawn from recent Festivals, is a collection of essays interspersed with photographs, poems and a piece of science fiction writing. The authors are experts in their fields, and a few are well-known names.

The essays are diverse: some are chapters reprinted from other books but most have not been published elsewhere. They are up to date and readable, but much of the content will be familiar to anyone with a good general knowledge and an interest in current science. The chapter by Richard Dawkins from one of his books reflects his well publicized views on evolution. Sir Crispin Tickell has a reputation as a campaigner for the environment, and puts forward views which are well known, acknowledged as sensible and (as he is all too aware) often ignored.

An account of the archaeological investigation of some Scottish lake dwellings is refreshing because it is unfamiliar, and it also provides local interest. An essay on 'Genes, Cancer and Prevention' tells of some medical research, but most of the contributions are about popular science or science policy: there is no 'hard' science. The astronomer Patrick Moore contributes an essay on extraterrestrial life. Another piece looks at artificial life, in the form of 'digital organisms' in computers. The science fiction story combines both these themes, but leaves so many loose ends it seems unfinished. An essay on girls in science is unexceptional, though what it says needs repeating until the situation is corrected. The essay on criminology might raise right-wing hackles, but the arguments are well rehearsed and have not been seriously challenged. The piece on the ethics of animal research will not be considered balanced by the animal rights fraternity.

These examples give an idea of the content. Not everyone will appreciate the mingling of poetry and serious essays but it is a worthy book, and well produced apart from a few irritating features (in particular, the size and layout of some of the photographs do not show them to advantage). Thanks to support from The Post Office, it is not expensive. It ought to be well received at the Science Festival, but how will it fare afterwards in the bookshops? For those interested in the issues of science it will have some appeal, but for many of them it does not and cannot go far enough. Its purpose, however, is not just to speak to the converted but to communicate science and all that surrounds it to a wider audience. Sadly there is nothing in it sufficiently topical or eye-catching to suggest it will succeed in attracting many of those who might benefit most from it.

It is the custom in many American universities for university professors to adopt a course book which closely follows the physics undergraduate course which they are teaching. For many, that course book has been Halliday and Resnick. Wherever in the world university physics is taught then the names of Halliday and Resnick are known. The ferment of activity in the post-Sputnik era of curriculum development led Halliday and Resnick to produce a preliminary version of their book, Physics, in 1958. Since then there have been four editions of Physics and four editions of Fundamentals of Physics, the last in 1992 and 1993 respectively (all published by John Wiley).

In 1993 a conference was held at Rensselaer Polytechnic Institute on 'The Introductory Physics Course' to honour Resnick on his retirement. This book is the proceedings of the conference. This was no nostalgic looking back at physics educational publishing. The 13 invited speakers and 25 poster presenters have produced between them a superb contribution to the debate on 'where does university physics teaching go from here?'. I began by dipping into some of the articles but soon found myself reading the book from cover to cover. It is a fascinating read with messages for course designers everywhere. The overriding message appeared to be that `all is not well with Physics Education at the moment and here is what we are trying to do about it'. In the lifetime of Resnick's books the numbers of students pursuing physics courses worldwide have increased. No longer are students destined to become clones of their teachers; many students do not wish to continue with physics beyond the end of their course. The preparation of students in school for study at university is changing; more is now known about how students learn and the difficulties they have in understanding physics concepts. There is more known about how little students really learn and how lecturers put them off physics. Students want contemporary physics (physics in use today) and yet they don't understand the basic concepts such as Newton's Laws. There is also a great disparity between research physics and taught physics. It is estimated that 95% of all physics texts is universal and 95% is pre-1935.

It is difficult to choose to comment on any article but I will dip into some of them. Resnick's own contribution covered the development of Physics from its origins as a course for engineers at the University of Pittsburgh. The religious fervour at that time (late 1950s) to do something about science teaching led to Halliday and himself being given a contract without a word of the manuscript being seen. The book was fully trialled for three years before it was published. When it was, not one review commissioned by the publishers was favourable, which is a warning to us all! The arguments of depth and breadth continued then as now. It was realized then that textbooks can't do everything and that more attention should be paid to

how we teach who does the teaching to whom and not just what we teach.

It was suggested that the focus should always be on the students, their work habits, prior knowledge and cultural expectations. It was also recognized that the pressures of teaching and research on lecturers have also increased too. Arons warns us that there is too much writing for peers and not enough writing for students and that research on how students learn is now respectable. Many articles refer to the use of the microcomputer in learning, both in laboratories and in classes, the role of the lecturer becoming that of mentor with all the time constraints that this implies. A plea was made that lecturers and teaching assistants should have the opportunity to learn in the way that they are expected to teach.

The humorous poster article on Halliday and Resnick's ' Physics Through the Years' took a light-hearted look at the diagrams, comparing the pictures with the increasing age and stature of the author. An international flavour in the debate came from China and Germany, both countries working in a changing educational environment.

The 357 representatives from high schools, colleges and universities in six countries appear to have produced an up-to-the-minute debate which is tinged with optimism for the future. If you are thinking of changing your university course then this book is a mine of information and references to help you on your way.

There are a very large number of texts available from the US covering the established syllabus there for college physics. The market is large with the books being used for degrees in engineering, biology, chemistry and medicine as well as for physics degrees themselves. Used in the UK, much of the content is at a level largely restricted to that studied by physics degree students in foundation year through to second year at university. Fundamentals of Physics is one of the long-standing texts. (There is also a slightly different competitive textbook Physics involving two of the same authors and the same publisher.) It is well-tried and has gone through a series of improvements with each edition. The mathematical content is not particularly advanced but it does routinely use calculus.

The book is clearly written with coloured illustrations and the usual extensive range of questions, exercises and problems. An attractive feature is a puzzler page at the start of each chapter with the answer to be found somewhere in the chapter itself. The regular edition covers mainly traditional subjects, mechanics, energy, fluids, oscillations and waves, thermo- dynamics, electrical circuits, magnetic fields, interference and diffraction, and so on. It includes a final chapter on relativity. An extended version is available to cover quantum physics and cosmology. As is usual with American textbooks, there is a range of available supplementary material including instructor's and student's supplements.

An important aspect of such a 1000 page book is whether it is of manageable size and will physically survive usage. This hardback edition should meet both criteria. On all counts, Fundamentals of Physics provides an introduction to basic university physics of lasting quality.

The name of the British cosmologist Sir Fred Hoyle will be familiar to all readers of Physics Education. His seminal work on the origin of the chemical elements ensures his place in the history of science, while his excoriating criticism of the Big Bang (a term he coined) and his enduring support for the competing steady state theory (which he helped to found) guarantee his wider fame

as an independent thinker and controversialist. Those who want insight into the forces that helped to shape Hoyle's remarkable character, and the events that have so often projected him into the limelight, can now turn to his charming, well-written and absorbing autobiography, Home is Where the Wind Blows.

Hoyle tells his story in the no-nonsense way that is to be expected of him. The ordering is mainly chronological with occassional departures to bring together thematically related issues. Thus, much of the material on the steady state/Big Bang controversy is included in the book's final chapter, together with Hoyle's post-1985 view that the creation of matter occurs spasmodically, rather than steadily, in a Universe that has an expansion timescale of about 800 billion years in addition to an oscillatory timescale of about 40 billion years.

Readers interested only in Hoyle's scientific career may want to skip the first hundred or so pages of the book, since these are mainly concerned with his parents, his childhood and his schooling. This might seem like a rather substantial amount of material to devote to what many will regard as a curtain raiser to the 'real' story, but anyone who does skip it will be denying themselves a treat. Not only are these early experiences, such as his glimpses of his father's business dealings in the textile trade, crucial to understanding his later distrust of opinions that are not based on observed facts or mathematical calculations, but, more importantly, the opening chapters are amongst the most atmospheric and spellbinding of the whole book.

Hoyle's years as a student in Cambridge are well described, with his rise from the middle of the slow stream in mathematics to the top of the fast stream being especially clearly related. Also well described are some of his interactions with the famously taciturn quantum theorist Paul Dirac, who eventually became his research supervisor. (This was an extraordinary arrangement, with Hoyle - the student who didn't want a supervisor - nominally under Dirac - the supervisor who didn't want a student.) The relationship between Hoyle and Dirac had an appropriately eccentric beginning with Hoyle ringing Dirac to invite him to give a talk and Dirac saying he would '... put the telephone down for a minute and think, and then speak again.' There are many similar stories concerning other scientific luminaries, including the astrophysicist Sir Arthur Eddington, who, according to Hoyle, '... never, in my experience, finished a sentence even in the course of a whole hour's lecture.'

The years of the 1939--45 war, during which Hoyle worked on radar, provide the expected wealth of scientific problem solving and bureaucratic bungling, but it is the post-war years that provide the crucial scientific chapters. Amongst these later chapters one topic that is bound to be a focus of interest is the tale of the friction with astronomer Martin Ryle and the related university politics that eventually caused Hoyle to resign his post as Director of the Institute of Theoretical Astronomy, and quit Cambridge in 1972. Hoyle does not hesitate to name names in this part of the book, nor does he disguise his dislikes for the 'gross efflorescence' of fluid mechanics which he sees as an example of the bad driving out the good in the Cambridge Faculty of Mathematics.

Those with little or no interest in the internal problems of Cambridge University will still find much to interest them in this book. Hoyle has lived through interesting times and moved in influential circles. This tale of his rise from humble origins to the heights of the British astronomical establishment (he is a former President of the Royal Astronomical Society) will provide interesting reading for anyone with an interest in science or education. Throughout the work there is the sense of a questing intellect, appreciative of the pleasures of family and friends, of mountains and the outdoor life, of music and science. There is the feeling of a man trying to be honest about himself, of someone who appreciates his good fortune, and, above all, of someone who thinks for himself and enjoys doing so.

This is one of the first booklets produced by the Supported Learning in Physics Project, SLIPP, at the Open University. Together the eight SLIPP booklets will provide not a single physics course post-16, per se, but a set of resource materials which have been written to cover the core A-level physics curriculum and which could be used as the foundation of any new A-level course. It is unlikely that a student will reach A-level standard with a satisfied mind if the SLIPP books are their only source of stimulus. I would expect most teachers to integrate the SLIPP materials into a more structured scheme of work to suit their situation.

However, much progress can be made by an independent approach to learning, and the SLIPP philosophy has been to place the student at the centre of the learning process and to relate physics principles to real life contexts. Each booklet includes plenty of good physics presented through practical 'explorations', problems to solve, background reading and progress questions. Being written in such an accessible and guiding style, the SLIPP booklets will, I am sure, provide a resource which will find much support from teachers. The hard work of relating physics to familiar applications has been done by the SLIPP authors.

In Physics, Jazz and Pop students are introduced to sound waves and mechanical vibrations and then progress to apply physics in the context of musical instruments. The second half looks at the ways in which sounds can be transmitted and recorded in the context of the recording of a concert. It is here that students will find out about microphones, loudspeakers, amplification, magnetic tape and compact discs. The final section looks at the design of a concert hall from the perspective of an acoustic engineer. The booklet provides guidance and feedback to students as they make progress through the material. There are ready-to-study tests at the start of each section, as well as a summary of expected achievements and a glossary at the end of each section. All questions are provided with answers. In the body of the text the student is frequently asked a searching question based on the preceding paragraph - these are immediately answered, providing the learner with an instant check on understanding.

There is much to recommend in this publication. The material has been trialled in schools and is attractively presented in two colours with appropriate black and white photographs and very clear line drawings throughout. The page layout makes use of boxes to frame key passages and the occasional cartoon to raise a smile. The OU team and in particular Richard Skelding and Mike Bethel, authors of Physics, Jazz and Pop, should be congratulated in setting a new standard in this student-friendly approach to learning physics. I would look out for the remaining SLIPP publications.

This is an excellent book. It's so easy to assume that students struggle because the science is so difficult when it is often a lack of study skills that holds them back. This is the book to give them confidence. In the authors' words, this book is written for ... 'students of mathematics, the sciences and technology (including engineering). It is designed to help improve your study skills, whether you are just starting out or have been studying for some time.' As you would expect from the Open University this is achieved through a mix of case study and information and engages the reader in activities. It is a frinedly book full of comforting information - 'what examiners like to see in exam scripts', 'organising your notes', 'how to quote references', 'reading mathematics'.

The book includes a great deal of mathematics. A quarter of the pages are taken up by a section called Maths Help. This is a summary of helpful topics at about GCSE level. Each topic is supported by activities with the answers given immediately afterwards. Further attention is paid to mathematics in two chapters: Learning and using mathematics and Working with numbers and symbols. One example of the realistic approach taken by the authors is a figure of some text to illustrate how different numbers are said (i.e. 1993 is not read the same way for a date as for a value).

The tone of the book is not to preach some perfect set of rules to follow but to present a totally realistic view of the demands made on a contemporary student, with boxes headed 'Why is it so easy to be distracted when you are studying?' and 'Computer-induced inefficiency' and then to offer a range of strategies to get round these problems. Summaries are placed at appropriate places in the book. Sometimes these are Key Points from the preceding section and at others Hints and Tips, e.g. Five hints for clear writing. Some of the advice is brought out via examples of the challenges awaiting imaginary students in similar situations, and then inviting the reader to think about their own responses. Case histories are used well; some quite personal. In the middle of the chapter, Studying with Computer, the author describes how he was plagued with a computer gremlin while writing it and how he saved the day and his text. There are constant Activity Breaks where questions are directed at the reader. An article, reproduced from the New Scientist, is used in several places. First, it is met in the section on reading and used as the basis for several activity breaks. Here the author acknowledges the impossibility of commenting on the reader's responses to questions like 'Did you enjoy reading the article?' so she offers her own first impressions of this article, which are a little critical. Later the same article is used very effectively to illustrate the use of diagrams.

Nuggets of advice include: 'Giving up on a problem may mean you are a person who organizes their time well and refuses to become obsessed', 'In a lecture you have to trade off listening against thinking so writing lengthy notes means you have to find time to do the thinking later'. Good writing isn't easy. This book would be extremely helpful for any student because it explains what skills are expected and how to practise and improve them.

This CD-ROM will operate on a 486DX/33 MHz or greater PC or a LCII 68030 or greater MAC with 8 MB RAM, double speed (or faster) CD-ROM Drive, 13" monitor (640 × 480) with 8 bit graphics, 8 bit MPC compatible sound card, QuickTime 2.1 (supplied).

The disc contains over 3000 multiple-choice questions (about 1000 on Physics) based on the GCSE syllabuses of all the major examination boards. Each question has five responses A to E with a single correct solution. A syllabus pick screen allows the user to select a particular syllabus, e.g. Double Science, MEG, and then select the subject, section and category, e.g. click Physics, click Forces and Energy, click Momentum. Next, by dragging a slider the number of questions in the test can be chosen. Questions can be selected from one or more of three levels of difficulty, as defined by the National Curriculum, i.e. levels 10 - 8; 8 - 6; 6 - 4. The sections mentioned above are divided into Sound, Hearing and Light; Space and Communication; Electricity, Magnetism and Electronics; Forces and Machines; Fuels and Energy Resources. Each section has a number of subsections (categories).

The package was straightforward to load. The instruction screens are clearly laid out with suitable coloured icons or buttons. The package is very user- friendly and the participant has no difficulties in quickly changing instruction screens to select questions. Once a test is chosen, e.g. 8 out of 50 questions available related to the category Momentum, the screen is filled with the first question, which may include a three-dimensional model animation, a still-rendering, a photograph or a two-dimensional animation. When a correct answer is selected, a bright `ping' is heard, a text explanation box at the bottom of the screen displays a short paragraph of explanation related directly to the topic, amplifying the answer to the question. There may also be a change of picture or an animation introduced. When an incorrect answer is selected, a dull `ping' is heard and nothing happens. The participant can then continue to select letters until the correct one is chosen. The test can be exited at any stage and returned to later. The level of difficulty of each question can also be displayed if desired in a small box at the edge of the screen. A separate progress screen can be called up to display the student's progress by subject, section or category.

I selected a sample of questions at random from the various sections and was unable to find serious fault with any of the questions or explanatory paragraphs. This appears to be an excellent way of revising a subject without losing interest and falling asleep. The continual variation of the screen enabled me to pass half an hour without losing attention. This CD-ROM is a useful facility to have available for any student to help him or her to revise, correct misconceptions and extend knowledge for any science GCSE examination.

A network version of the CD is available containing two programs: Teacher and Student. Here the teacher can pre-select the questions for a test or revision exercise. Each student's score is recorded, enabling the teacher to review and record individual and/or class progress.

Bradford Technology have added to their growing list of physics CD-ROMs with this new disc on light and sound. These topics are still popular in science teaching despite the unfair lack of curriculum coverage which is now given to sound, due mainly to the National Curriculum straightjacket. This CD-ROM will offer tremendous help to the science teacher and to the student in learning these areas at Key Stage 4.

The disc follows the usual, now familiar Bradford Technology menu and format which makes it easy for users to find their way around and move from one part of the disc to another. It gives a comprehensive coverage of light, ranging from rays and shadows, reflection and refraction to a more complex treatment of lenses, the eye and colour. The treatment of colour is worth the disc money in itself because that mixture of red, green and blue lights which physics teachers try to persuade their pupils makes white light actually is white. Virtual reality is so much more reliable than the real thing. Topics such as real and apparent depth and critical angle are treated carefully and rigorously in the usual BTL fashion - straight down the line physics as it should be taught. Animations and ray diagrams help in teaching some of the more difficult ideas in optics. As is customary with BTL discs, a spoken commentary (in the crisp Northern voice of Bob Gomersall) is given simultaneously with the text on the screen. It is debatable whether this aids understanding but it will certainly help poorer readers.

The section on Sound also give a good coverage of the important ideas ranging from a look at sound waves - with some useful animation showing the difference between transverse and longitudinal - and a useful simulation of another of those experiments which never works 'for real': the measurement of the speed of sound using a wall and its echo. This forms part of the Virtual Laboratory which is now an expected feature of Bradford discs. The debate about whether experiments should be done on screen or with real objects will live on, but at least this disc's experiments do give different values for the speed of sound (albeit around about the expected value), which gives it some extra reality.

Light and Sound also has 'Quizzes' in the form of multiple choice tests and a glossary of terms which lead to a full explanation of ideas such as 'lunar eclipse'. Both are ideal for revision.

The disc comes in the now familiar BTL white wallet with a good collection of photocopiable worksheets which teachers can use to structure and support the disc's use either in class, the library or for the lucky students with multimedia at home.