The 25th Annual Stirling Physics meeting took place on
Thursday 20 May on a warm sunny day when the country
setting of Stirling Campus could be seen at its best. A total of
225 participants from all sectors of physics education attended.
There was an opportunity to view and discuss with exhibitors a
wide range of state-of-the-art equipment and teaching materials
both before and after the meeting.
The theme of the meeting was `Maintaining Standards'. Gemmel
Millar, Scottish Branch Secretary acting as Chairperson for the
morning session and in anticipation of the first speaker,
wondered if a new unit qualification, the `Planck' might be
introduced. Half units would then be `Short Plancks' and how many
Short Plancks must there be in a unit? Great stuff.
Scottish Qualifications Authority
Hugh McGill began with a brief history and description of the
Scottish Qualifications Authority.
Born on 1 April 1997 (a light frisson of amusement swept
through the audience) it was a unification between SEB and
SCOTVEC and has a range of responsibilities covering schools,
further and higher education. It oversees Standard and Higher
grades, HNC and HND and SVQs, and it has 500 full-time
employees as well as some 13500 appointees who act as examiners,
assessors and verifiers etc, without whom its remit could not
be carried out.
The committee structure of the Board was outlined, one each for
national and higher national qualifications and a third for
Scottish vocational qualifications. These will be served by a
proposed 19 Advisory Groups. The Science Advisory Group
will be the key body for advising SQA on strategic
developments to ensure that qualifications meet the needs of
both client groups and end users. A consultation paper `Added
Value To Learning' was referred to, in which all qualifications
available in Scotland are given parity of esteem on a rising 11-point scale.
Mr McGill stated that standards would be best maintained by
ensuring continuity in procedures developed over many years.
The Physics Sub-panel would still exist. Nominees from this
would serve on the Science Advisory Group. An Assessment
Panel for physics would be created and a Principal Assessor
would be appointed for three years to oversee both Higher and
Advanced Higher. There would be continuity in retaining
Arrangements Documents.
National Physical Laboratory
Metrology, the science of measurement, was the subject of
a fascinating and wide-ranging talk by Dr Keith Berry.
He described the
origins of NPL, established in 1900 in Bushy House, a Royal
property donated by Queen Victoria and not far from Hampton
Court. Added to over the years, it now covers 60 acres and
employs 700 staff, of whom 500 have professional qualifications
in Metrology. NPL holds over 100 standards.
Dr Berry, in
addressing the fundamental units of mass, length and time,
described the evolution of the standard metre, defined originally
200 years ago as one ten-millionth of the polar quadrant running
through Paris but in reality referenced to a standard platinum
bar. The bar and its variants survived until 1960 when the metre
was referenced to the wavelength of light from 86Kr. It is
currently defined in relation to the speed of 633 nm light emitted
through a vacuum from a stabilized HeNeI laser (1983).
Research was under way to redefine the standard kilogram with
something more reliable than the current platinum–iridium
standard kg, accurate to only 1 part in 107, possibly by counting
the number of Si atoms in a standard macroscopic sample.
Refinements in the standard second led to the development of
the atomic clock with an accuracy of 1 part in 1013. This will
vary by no more than 1 second in 300000 years. It is now
widely used in GPS satellite technology.
All measurements have to be traceable back to a national
standard but each step in the calibration chain results in a loss of
accuracy.
Towards the middle of the 19th century, anomalies in national standards
(the UK for example had a different length standard for imports
and exports!) resulted in the establishment of the Convention Du
Mètre, an agreement on the definition of a standard metre to
which all signatories would adhere. This now has 48 signatories
and has given rise to the International Bureau of Weights and
Measures located near Paris but technically not in France
(merely surrounded by it). The French Government has
accorded its couple of acres international status. The Bureau is
the Secretariat to the International Committee on Weights and
Measures and it is this committee which has overall
responsibility for international standards.
Dr Berry described a proposed international agreement which
all national standards institutions will be required to sign.
This will result in the production of a database listing the standards being
used in all the participating countries and will be totally
transparent.
Uncertainties were touched on. A draft NPL document entitled
`A Beginner's Guide to The Uncertainty of Measurement'
already exists and will be made available to the profession in
due course. The Scottish Branch was invited to have an input to
this publication.
Dr Berry concluded by describing a number of
interesting everyday examples in which measurement was
critically important. These ranged from calibration of aircraft
altimeters by pressure measurement to the equalisation of
National Lottery balls to a paltry 1/1000 inch (more non-SI
units!). The audience was left with much to take back to the
classroom from a valuable and entertaining presentation.
Advancing Physics
Philip Britton set the scene in a light-hearted and often hilarious
introduction, e.g. `when you're in a room full of physicists you
don't feel so awkward because everybody else is weird'. The Advancing Physics initiative, he explained, was an
Institute of Physics
response to a deteriorating situation within physics education in
England and Wales, particularly in the following areas:
too few young people south of the border are choosing to study
physics;
the ratio of boys to girls taking physics is too high;
a restricted framework of A-level qualifications currently
exists;
there is a crisis in recruitment of physics teachers with only 60
signed up to train for next year.
In response, IOP is investing half a million pounds in the
initiative. Teachers are at the heart of
Advancing Physics,
as exemplified by the following: a national physics teachers'
network, a newsletter, database and website.
Some features of the website were described: as a forum for
teacher discussions it permits considerable input via an
e-mail list to which teachers can subscribe and list messages. A
series of resource discussion booklets: `Making Physics
connect', `Shaping the future', `Maths in Physics', `Physics in the
study of matter' were also highlighted.
The jewel in the crown of Advancing Physics was a brand new
A-level physics course (not merely a syllabus) supported by
`serious' IT in the form of a CD-ROM, together with
comprehensive teacher's notes and course book.
The new CD-ROM was skilfully previewed by Ian Lawrence,
who guided the audience through a small selection of the many
layers of its fascinating and enticing menu.
Philip concluded by assuring us that the Advancing Physics
initiative was for everyone and he expected a significant spin-off
for the Scottish curriculum and the physics profession north of
the border. The audience was greatly impressed with the
prospect of an exciting new resource and by a truly memorable
presentation.
Higher and SYS Physics prizes
Lunch was followed by the presentation of prizes to the
highest scoring candidates at Higher and SYS (sixth year
studies) physics in 1998.
It was noteworthy that there were six equally placed candidates
for the Higher prize, each scoring 100%:
Higher
Alistair Gilmour, Mackie Academy, Stonehaven
Andrew J Hood, Boroughmuir High School, Edinburgh
David Borthwick, Gracemount High School, Edinburgh
Iain D Drummond, Denny High School
Lynsey Granger, Kilmarnock Academy
Andrew J R Allen, Greenock Academy
SYS
Andrew D Wilson, Queen Anne High School, Dunfermline
The prizewinners clearly enjoyed the presentation and were
accompanied by members of their families and
physics teachers from their own schools.
Long service award
Dr Norman Fancey paid a warm tribute to Alan Duncan, one of
the original organizers of the Stirling Meeting in 1973 and who
continued this work for many years afterwards. Dr Fancey thanked
Alan for the considerable thought, energy and effort which he
had expended on our behalf. Alan was presented with a
handsome decanter; in reply he thanked the Branch
Committee, his wife for her many hours of unpaid secretarial
help and his colleague and friend, Jim Jardine, for his many years
of support.
Missing from the official programme simply to guarantee the
presence of its self-effacing recipient was a surprise
presentation by Heather Reid to Jack Woolsey for his many years
of organizing the Stirling meeting. Jack, suitably abashed,
received his gift to roars of approval from the audience.
Chaos
In a witty, well-rehearsed and entertaining set piece, the
audience was presented with an introduction to chaos by
Sarah Thompson and Jim Matthew of the University of York.
Jim played the part of a convergently thinking prechaotic
mathematician who contended that everything could be
circumscribed by existing (non-chaotic) mathematics, and Sarah
was a laterally thinking chaos junkie and practitioner of this new
mathematics, which is embedded in the behaviour of simple
physical systems.
Some simple chaotic systems were examined: an insect breeding
system, a pendulum with magnet under the base, an electrical
circuit with a diode (plus other unspecified components), a
weather-chart. Each in turn was examined in great detail. The
insect system was a computer model and illustrated perfectly
how a small change in input conditions could produce massively
different outputs. We could see the characteristic period
doubling and period trebling. Fractals were clearly visible. Jim
of course dismissed all this as a property of the computer
software. A real diode circuit was then produced and examined.
Initially, for small input amplitudes, a sinusoidal input voltage
produced a rectified sinusoidal output with the same period. The
amplitude of the voltage input was then increased and the output
voltage/time graph examined. The output period had now
doubled. Further increases produced period trebling. Jim
conceded there might be something in it but insisted on returning
to the simple pendulum, which he thoroughly understood. Sarah
agreed but wanted to examine a simple pendulum with forced
oscillations using a computer model. Again, changing the size of
the input force produced the characteristic period doubling seen
in earlier examples. Basically he had to concede the argument.
Sarah explained that chaotic systems exist in familiar contexts
such as astronomy, meteorology, molecular vibrations, plasma
physics, fluid dynamics and the stock market! Chaos limits
scientists' ability to predict the future but has applications
in, for example, detecting arrhythmic beating of the heart (period
doubling again) and is the subject of much research. Chaotic
systems are ones in which changes in initial conditions produce
massively different outcomes. This chaotic effect may not be
detectable until some time has elapsed from the input change.
The final example was a meteorological one in which two
slightly different weather charts were computer modelled over a
period of several days and ended up predicting entirely different
results. Jim Matthew concluded by thanking the technician
who had assembled the demonstration apparatus. The audience
had been treated to an entertaining, informative and thought-provoking
presentation.
London representative
Catherine Wilson was delighted to be up at Stirling yet again. It
was good, she said, to meet Alan Duncan for the first time and
all the participants were to be congratulated on such a successful day and
engaging programme. She was particularly pleased to see the
presentation of prizes taking place at the meeting and felt that
these young people encapsulated what the event was all
about. Catherine expressed her wish to be with us again next
year.
Drawing the meeting to a close, Heather Reid thanked all those
who had attended.
Postscript
We were shocked and saddened to learn of the
untimely death of Alan Duncan in July. A full
appreciation of Professor Duncan's contribution to physics will
appear elsewhere in the physics press.