Tag Archives: Physics

Thoughts on SQA Exams & Certification⤴

from @ stuckwithphysics.co.uk

In response to a discussion about assessment on the IOP Sputnik email forum for Scottish Physics teachers, I posted some thoughts on what the SQA could do differently. Some replies to the post suggested I should share these ideas further.

It's a bit 'sassy' in places, as one of the replies put it, but here's the post, sass and all -

Alasdair replied to an earlier post saying ' If only the SQA had a big bank of questions in single page word format, say 20 for each key area, and some kind of random test generator software. '
At the risk of this opening a can of worms and with apologies to anyone who has ever had this discussion with me in the past...

If the SQA had a bank of questions they could relatively easily use it to automatically generate unique assessments that candidates could complete entirely electronically, that could be marked, totalled and graded automatically, either as individual key areas/units or as a full course assessment. Any such system could probably automatically certificate the candidate at the appropriate level, and award tariff points too. And if such a system were live all year round, candidates could learn at their own pace, within reasonable bounds, and choose the date and time that they took the assessment. Dare I say it, a bit like a driving theory test...

Such a system might also allow candidates a number of attempts at an assessment, until they achieve a pass (perhaps with a period of time between to consolidate and revise), rather than writing them off after two attempts. A bit like a... oh, you're there already...
For those candidates who *need* an exam grade for Uni entry (they could just do their own entry exams), or those so ingrained in the 'exams are the only thing of any importance' culture that pervades all discussions of education, there is no reason why terminal exams could be not be continued - perhaps with those candidates gaining extra tariff points for the additional attainment. A bit like a driving licence awarded after a practical test...
Granted, schools would need to verify the identities of the candidates attempting assessments (so their big cousin isn't doing it), have a dedicated suite of PCs on which these assessments could be done where online access is limited to only the assessment site, and have a reliable internet connection with sufficient bandwidth. A bit like those places where you do your ..., oh, and again...
These arrangements would require a significant investment, but might go some way to allowing all candidates to achieve at a level that is appropriate to their abilities. There's every chance they could contribute to reducing the attainment gap (if not the poverty that causes most of it) and no doubt whatsoever that they would significantly reduce teacher workload.
If only the SQA had such a bank of questions...
And if they do, then why aren't we doing things better by our kids and for ourselves?
Comments, as ever, are very welcome.

Nobel Prize in Physics⤴

from @ Engage for Education

Minister for Further Education, Higher Education and Science, Shirley-Anne Somerville, has congratulated David Thouless, Duncan Haldane and Michael Kosterlitz – the team awarded the Nobel Prize in Physics – for their work on strange forms of matter.  Two of the winners – David Thouless and Michael Kosterlitz – were born in Scotland.

Ms Somerville said:

“Congratulations to all three winners of the Nobel Prize for Physics for their work on states of matter, and I’m particularly pleased that two of the winners were born here in Scotland. I hope their achievements help to inspire our next generation of scientists.”

You can read more about the award here

Perimeter Institute – EinsteinPlus 2016 – Day 3⤴

from @ stuckwithphysics.co.uk

Day three began (after breakfast) with a session on Quantum Mechanics. The session was based around the 'Investigating the Nature of the Electron' activity from the Perimeter Institute's materials on 'The Challenge of Quantum Reality'.


The first task, 'Classical Particle Behaviour', uses very simple apparatus - sand and a paper coffee cup, to model the behaviour of particles passing through two narrow slits - Young's slits experiment. The task asks students to make a prediction of what they will see, encouraging them to explain their reasoning before continuing with the procedure of passing a small amount of sand through two narrow slits cut into the base of the cup.

As expected, two small piles of sand are obtained,

Perimeter Institute – EinsteinPlus 2016 – Day 3⤴

from @ stuckwithphysics.co.uk

Day three began (after breakfast) with a session on Quantum Mechanics. The session was based around the 'Investigating the Nature of the Electron' activity from the Perimeter Institute's materials on 'The Challenge of Quantum Reality'.


The first task, 'Classical Particle Behaviour', uses very simple apparatus - sand and a paper coffee cup, to model the behaviour of particles passing through two narrow slits - Young's slits experiment. The task asks students to make a prediction of what they will see, encouraging them to explain their reasoning before continuing with the procedure of passing a small amount of sand through two narrow slits cut into the base of the cup.

As expected, two small piles of sand are obtained,

Perimeter Institute – EinsteinPlus 2016 – Day 2⤴

from @ stuckwithphysics.co.uk

Day 2 of EinsteinPlus 2016 saw the group formally welcomed to the spectacular Perimeter Institute building after an equally spectacular breakfast. (There are two excellent bistros at PI, which provided the group with a fabulous range of meals over the week long visit. I'd say more, but there'd be a real danger of this becoming a food blog...)

The morning session was split into two -

  • Cosmology - this used an existing PI activity 'The Signature of the Stars' from their educational resource on 'The Expanding Universe' - using diffraction glasses observations were made of line spectra from a variety of gas discharge lamps. These spectra are used to identify the elements present in stars, in the Milky way and in distant galaxies. The spectra of light from distant galaxies shows the same spectral lines as stars in our galaxy, but the lines appear in slightly different positions, with longer wavelengths. This effect, known as Red Shift, occurs because the galaxies are moving away from us, and each other, at high speeds. Measuring the red shift for a galaxy can be used to measure its speed, which relates in turn to its distance from us. This effect was first observed in the early 20th century and used to formulate Hubble's Law - which states that not only is the universe expanding, but the further away from us a galaxy is, the faster it is moving. The activity includes data allowing the red shift of a range of galaxies at different known distances to be used to find their speeds. This data is then plotted it give a graph representing Hubble's Law, which gives an approximation of the Hubble constant and can in turn be used to find the age of the universe.

  • Gravitational waves - this used a newly developed activity based around the recent detection of Gravitational Waves at the Laser Interferometer Gravitational Wave Observatory (LIGO) facilities in the USA. The facilities use extremely large scale (~4km) laser interferometers to measure incredibly small expansions or contractions (~10-19 m - 1000 times smaller than the diameter of a proton) of the devices which occur when gravitational waves pass. There are many areas of physics and engineering involved in the development and operation of the LIGO detectors, from the solutions to Einstein's General Relativity which predicted the existence of Gravitational waves, to the intricate suspension of the mirrors sued to improve the sensitivity of the detectors - developed at the University of Glasgow. The activity centres around the properties of waves, and their behaviour when they undergo reflection - beginning with demonstrations of mechanical waves using a slinky. Observations of phase change upon reflection were developed upon and related to the operation of the interferometers at LIGO. These ideas were utilised in a hands on activity to simulate the paths of the laser light used at LIGO in order to find the nature of the light detected when the device is unstretched (no gravitational wave) and stretched. This task offers an excellent opportunity to link this part of the Advanced Higher physics unit on waves to a context which involves real, cutting edge physics.

LIGO unstretched

LIGO stretchedAfter lunch, followed a two more sessions -

  • Neutrino Detection - another new activity, this is based on the Nobel Prize winning work of Professor Art McDonald and his team at the Sudbury Neutrino Observatory (SNOLAB). The session began with an overview of the production of neutrinos in the sun and the difficulty in detecting these particles - the 'Solar Neutrino Problem'. The session continued with a description of the facility at SNOLAB and a hands on task modelling the detector using marbles, cardboard boxes and a baking tray. There was a great deal of discussion about this task, and the nature of the model to describe and explain neutrino detection. Consequently there was a shortage of time for the remaining tasks, dealing with real data from SNOLAB and the theory of 'neutrino oscillation'.

  • Dark Matter - this session used the 'Dark Matter Within a Galaxy' activity from 'The Mystery of Dark Matter' materials. The activity begins with a revision of the basic rules for circular motion and gravitation, using a range of data to find and plot the orbital speed of a star against its radius from the centre of its galaxy. These values, calculated from classical theory, do not compare well with observational data - implying that there must be more mass in these systems that we can not detect - Dark Matter. Whilst the part of the underlying physics of this task, circular motion, is beyond the scope of the Higher physics course in Scotland, it might be fair to use this as a practice data handling task which could be used to exemplify and reinforce the very brief mention of Dark Matter in the 'Our Dynamic Universe' unit.

The final session of the day was a keynote presentation delivered by Professor Avery Broderick from the University of Waterloo on the Event Horizon Telescope (EHT). This program uses nine existing telescopes across the globe and applies a technique known as Very Long Baseline Interferometery (VBLI) to improve the resolution at which images of very small objects can be made.

It is hoped that by improving the resolution for existing telescopes and including planned future telescopes in the gathering and processing of data, the EHT will obtain the first direct images of the event horizon for a black hole in our galaxy. Recent observations in the constellation of Sagittarius are thought to indicate the presence of a black hole with a mass around 4 millions time that of our sun. This black hole is of the right size and at the right distance for the EHT to be able to make observations that will allow an image to be obtained in the next few years.

The data gathered and images obtained by the EHT will allow for further testing of Einstein's theory of General Relativity, and provide a greater understanding of phenomena such as black hole accretion and plasma jets.

After this presentation and another excellent meal the group was offered a tour of the Perimeter Institute building, offering an insight into how the facilities have been designed and developed in order to attract and facilitate the work of some of the world's foremost theoretical physics (not to mention a very large number of teachers and students).

A selection of images of the building will be included in a gallery as soon as I figure out how to make it work...


Glow TV at the Edinburgh International Book Festival⤴

from @ Education Scotland's Learning Blog

EIBF.JPEG ImageGlow TV will once again be at the Edinburgh International Book Festival and you can join us too!
We will be broadcasting two events this year and you can sign up now to take part:

The Horrible Science Show – Monday 22nd August at 1.30pm
Join us for this exciting session to learn some mind-blowing facts about chaotic chemistry, bloody biology, and frightful physics as the Horrible Science books are brought to life!! With Nick Arnold’s scary stories and explosive experiments and Tony De Saulles’ crazy cartoons (volunteers may be required…!). Expect a lot of laughs, a feast of foul facts and some seriously squishy science. Register to take part now – The Horrible Science Show

In Those We Trust – Wednesday 26th August 12.15pm
Join authors Keren David and Alex Wheatle for a discussion about diversity and keeping it real in Young Adult fiction. Alex’s latest novel Crongton Knights is about a boy growing up on a tough south London estate, while Keren’s Cuckoo is about a child star who has fallen on hard times and becomes homeless. Find out what inspired these two hard-hitting, but ultimately moving, novels. Register to take part now – <a href="http://“>In Those We Trust

If you unable to join us for the live events you can always catch up with the recording at another time – Glow TV’s Watch Again.

Newton’s G-ball⤴

from @ stuckwithphysics.co.uk

'Newton's G-ball', marketed by Swedish company Mollic, is a simple electronic timing device which can be used to measure the the freefall time from its point of release to impact on a surface below.

It is available from a number of third party suppliers, including djb microtech and Better Equipped in the UK and Arbor Scientific in the US.

gballThe ball has an integral centisecond timer, which is primed by pressing and holding the button on the face of the timer. Releasing the ball starts the timer, which stops when the ball impacts upon a surface below.

If the height, h, through which the ball falls is known, and the time for the ball to fall, t, is measured, then g can be calculated using the formula -


Taking multiple measurements of the freefall time, t, over a range of heights, h, allows a range of values to be obtained for g.

The results below were obtained by my Higher Physics class on 9th June 2016.

h (m) t1 t2 t3 mean t (s) g (ms-2)
0.2 0.23 0.22 0.27 0.240 6.94
0.4 0.30 0.27 0.30 0.290 9.51
0.6 0.39 0.35 0.38 0.373 8.61
0.8 0.42 0.39 0.41 0.407 9.67
1.0 0.46 0.48 0.46 0.467 9.18

The results obtained are reasonably good, giving a mean value for g = 8.79 ms-2. Whilst this is in reasonably close agreement with the quoted value of 9.8 ms-2 given in the SQA data tables, discounting the obviously low value obtained for h = 0.2 m gives an improved mean value for g = 9.51 ms-2.

A quick analysis of the uncertainties in this data give the following -

Uncertainties in height, h (approximate reading/position uncertainty = ± 0.02 m)

h (m) uncertainty in h (m) % uncertainty in h 
0.2 0.02 10%
0.4 0.02 5%
0.6 0.02 3%
0.8 0.02 3%
1.0 0.02 2%

Uncertainties in time, t -

h (m) t1 t2 t3 mean t (s) random uncertainty in t (s) uncertainty in t 
0.2 0.23 0.22 0.27 0.240 0.017 7%
0.4 0.30 0.27 0.30 0.290 0.010 3%
0.6 0.39 0.35 0.38 0.373 0.013 4%
0.8 0.42 0.39 0.41 0.407 0.010 2%
1.0 0.46 0.48 0.46 0.467 0.007 1%

Uncertainties in g -

g (ms-2) mean g 


random uncertainty in g (ms-2)
6.94 8.79 0.55
8.61  % uncertainty in g absolute uncertainty in g (ms-2)
9.67  8% 0.70

This gives a final value for g using this procedure as -

g = (8.79 ± 0.70)  ms-2

However, an alternative graphical analysis allows an improved result to be obtained from the same data.

For this approach, the formula above was rearranged for h, giving -


A graph was plotted of h against t2, giving a good approximation of a straight line through the origin, as expected.

t2 (s2) h (m)
0.0576 0.2
0.0841 0.4
0.1394 0.6
0.1654 0.8
0.2178 1.0


Using the trendline function in Excel, a best fit line was added with its function included. The gradient of this straight line, which is equal to ½ g, is 4.91, giving a value for g from this graph - g = 9.82 ms-2.

Further analysis of the graph, using the LINEST function in excel, gave the following uncertainties -

gradient uncertainty in gradient % uncertainty in gradient
4.91 0.33 7%
g (ms-2) absolute uncertainty in g (ms-2)
9.82 0.69

This graphical treatment of the data gives a final value for g using this procedure as -

g = (9.82 ± 0.69)  ms-2

I have included the raw data, graphical treatment and uncertainties in the in the excel file below.

g ball

Scottish Engineering Special Leaders Award – Niall Caldwell⤴

from @ Education Scotland's Learning Blog

Small- SESLA Niall CaldwallJoin us for the first opportunity to chat to an engineer who can help you as part of this year’s Scottish Engineering Special Leaders Award – Niall Caldwell.

Niall Caldwell is the Managing Director of Artemis Intelligent Power Ltd., which is a company based in Loanhead (near Edinburgh). They develop and commercialise our unique Digital Displacement (R) fluid power technology, an innovation which combines mechanisms with computers and electronics to make the world’s biggest and most efficient fluid power machines.

These days Niall spends a lot of time on the business management of the company, but he still finds time to do some technical work. He builds and tests mathematical computer models to predict how our machines will work when installed, for instance in a wind turbine. Using these models he can design the control system and predict the behaviour in all the different situations which can happen (for instance start up, shut down, emergency stop) before they actually build the machine. He makes these models by combining his understanding of the physics and mathematics of the machines with the results of experiments, to make a model which is complex enough to be realistic – while being simple enough to give an answer quickly. But no matter how much he thinks it through, when the machine finally starts working…there are always surprises!

Join Niall on Wednesday 3rd February at 11am to ask your questions and find out more!
Sign up now in Glow TV – Scottish Engineering Special Leaders Award – Niall Caldwell

If you unable to join us for the live event you can always catch up with the recording at another time – Glow TV’s Watch Again.

New videos for Science⤴

from @ Education Scotland's Learning Blog

NLSC logo




The National STEM Centre have just added six great film clips to the eLibrary, covering areas of the curriculum such as electricity generation, electromagnetism and the physics of car crashes.

The film clips in this collection were produced by Pumpkin Interactive, whose aim is to provide case studies of real life applications to illustrate some of the more complex scientific concepts and theories. Themes covered include: forces and motion, waves and imaging and electricity generation, transmission and distribution

Science, Technology and Maths e-bulletin September 2015⤴

from @ Education Scotland's Learning Blog

asdWelcome to our e-bulletin for sciences, technologies, engineering and maths (STEM).


Received this from someone else? Sign up to receive it directly.





  • Add the new SSERC tile to your Launchpad in Glow
  • Register for the sciences cross-authority writing group events 2015-16
  • STEM at the Scottish Learning Festival – enjoy our STEM programme
  • Food chain professional learning event – Thurs 17th Sept
  • Professional learning videos for vibrations and waves now live
  • Get learning section of Scotland’s Environment website now live – see data about climate change, water, rivers and more
  • Want your primary school learners to talk about science? Try these videos from RSC




Numeracy and mathematics


Did you know…….?

Scottish science festivals set to share £239k of funding


Professional learning

Creating a smarter Scotland – A draft National Improvement Framework for Scottish Education


Video Inspiration

Have you got Rugby World Cup fever yet? Watch the science behind the rugby tackle


We’ve got loads more news to share! See our STEM blog for the latest updates.