So, I'm now back from a lovely holiday in the UK, following a not-so-lovely period of being sick. Quite possibly I can also get back to blogging. Among the great many emails awaiting for me yesterday were a few about school physics and university physics. They were coming from different sources for different reasons, but […]
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A light puzzle
Here's a puzzling photograph that Hans Bachor showed me at the end of the NZ Institute of Physics conference last week. It comes from his public lecture on lasers a week ago. And we don't have the answer to it, so maybe you can enlighten us (pun intended). The photo is of a demonstration of […]
Continue readingNZIP2015 Highlights
So the NZ Institute of Physics conference is in full swing. I have a bit of a break between the end of the last session and tonight's conference dinner, so there's time to give some highlights so far. Well, first, the low-light: Like the rest of my family and half of Hamilton I've had a […]
Continue readingHigh-tech, Low-tech, planetary observations.

First the low-tech: The conjunction of Venus (the brighter one) and Jupiter as recorded by my very lousy cellphone camera just after sunset yesterday. Now the high-tech: A day before that Pluto occulted a star. It moved in front of the star, rather like an eclipse. The significance of the event was that it allowed […]
Continue readingThe equation of time strikes again

Some of us are rather looking forward to getting to 22 June. That's when the days get longer again. Yes, the reality is that no-one's really going to notice much difference for a while, but it's encouraging to think that the days will be getting lighter again, if only by a little bit. Don't confuse […]
Continue readingWhy you should clean your heat pump filters (the physics)
A couple of days ago I cleaned the filters in our heat pumps. What prompted me to do this wasn't the cold weather, but the visible build up of dust on the casing of the indoor units. It looked horrible. On opening the unit up, it was clear that the filters were well overdue a […]
Continue readingLenz’s law – at 3 tesla
When I was at school, and introduced to magnetic fields in a quantitative sense (that is, with a strength attached to it), I remember being told that the S.I. unit of magnetic flux density (B-field) is the tesla, and that 1 tesla is an extremely high B-field indeed. Ha! Not any more. Last Friday night […]
Continue readingSpecial relativity – not so easy to grasp

I’ve just given a couple of lectures on special relativity to a class of first years. It’s clear that grasping the key ideas is going to take some time. The results are so far removed from everyday experience that there is a certain air of bewilderment in the classroom. Here’s an example of what I […]
Continue readingDeveloping assessment literacy
I just love the word 'obfuscate'. It means (in my words) to take something that is perfectly clear, and render it incomprehensible. As in "Using the word 'obfuscate' in a sentence will obfuscate its meaning". I say this because I've just been reading an article on which (clearly) a statistician has been let loose – […]
Continue readingA blatant plug for the NZIP2015 conference
There's no hiding my conflicts of interest here. I'm on the New Zealand Institute of Physics 2015 conference organizing committee. I'm also the NZIP treasurer. And I'm a staff member at the host organization. So, to contribute to the New Zealand physics community's biennial event in Hamilton on 6 – 8 July, click on this […]
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