I went to a very informative seminar this morning by Peter Pott, of the Technical University, Darmstadt, Germany. He gave a very nice introduction to the world of piezoelectric devices. In short, a piezoelectric thing is something that acquires a voltage across it when it is squeezed, stretched, sheared, etc. They can be used as […]
Continue readingTag: oscillation
Bessel functions
I vaguely remember the following conversation from back when I was a PhD student. Student A: What’s a Bessel function? Student B (waving his arms about): It’s a wavy thing – goes like this, doesn’t it? Me: Sounds vaguely familiar – I think we did it in third-year. Student A: But what IS it? Me: […]
Continue readingPendulum mayhem
One of the main intentions of our 2nd year Experimental Physics paper at the University of Waikato is to have students learn how to put together a physics experiment that measures something, and to measure that thing in a systematic and robust manner. What that means in practice is dealing with uncertainties. Whereas the average […]
Continue readingEarthquakes and Polarized light
I had to get up early last Saturday to catch my flight back home from Dunedin to Hamilton, via Christchurch. My fears of sleeping through the alarm clock proved irrelevant as I was supplied with a rather more violent variety courtesy of plate tectonics underneath Christchurch. (Dunedin is a long way from Christchurch – given […]
Continue readingOne oscillation plus one oscillation equals how many?
I’m back from a fairly brief trip to Sydney, where I spent almost equal amounts of time talking to a collaborator in the School of Physics (Peter Robinson and his colleagues) at the University of Sydney and sat in traffic jams on buses / taxis (and waiting for delayed trains). Anyone who thinks Hamilton traffic is […]
Continue readingWhere the smart money is…
Mark Twain is reputed to have said on investment choices "Buy land – they’re not making it anymore". There’s got to be a good deal of truth in that – it’s hard to see that there will be a decreasing demand for land on a global scale in the next century (though there are perhaps […]
Continue readingPhysics is everywhere
One of the problems with being a physicist is that I start seeing physics happening everywhere I look. Here’s an example. Last week I was sitting in a cafe on Dunedin’s George Street enjoying a coffee with my wife, when the moment was utterly ruined by a completely inconsiderate couple on the other side of the […]
Continue readingMobile phone physics
Just occasionally, I have a crazy thought regarding a physics demonstration. This is one that I’m thinking about inflicting on my third year electromagnetism class. We’ve been discussing the way electromagnetic waves travel (or rather, do not travel) through electrical conductors. Basically, conductors allow electric currents to flow in response to an applied electric field (in simple terms […]
Continue readingWhat’s that buzzing?
(Amended to correct major factual blunder – whoops – and more details added from original post of earlier today). I was fascinated to read in the Herald this morning about the anti-teenager sounds that are being used to deter graffiti artists. High-pitched sounds that only the young can hear are being used to deter people […]
Continue readingBlue sky
I’m still working on the problem of why is the sky blue? Now, I’ve already told you its because the short-wavelength blue light is scattered more than the long-wavelength red light, but why are short wavelengths scattered more than longer ones? In words suitable for a blog. I could do some maths to show you […]
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