Lectures have finished; students now are into the exam period; and my thoughts naturally turn to research for the summer. To be more accurate, they first turn to marking the aforementioned exams and other assignments, but research will quickly take over. One of the projects we have going involves recording small electrical signals from a […]
Continue readingTag: waves
Diffraction
If you’re like me, you’ve been mesmerized by the colours created by reflections from a DVD or CD. The discs do a great job of splitting the illuminating ‘white’ light of your home light-bulbs into its constituent colours. But unlike a prism or raindrop, which achieve this effect through refraction (blue light travels more slowly […]
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 readingMore physics with aluminium foil
I gave a talk to the Junior Naturalists in Hamilton last Friday. It had some similarity to the talks I gave in June to the Osborne Days (year 12 and 13 school students), but I needed to change a few things because 1. The audience was younger, and 2. I wasn’t prepared to cart voluminous apparatus […]
Continue readingInfra-red and heat
Here’s a bit of physics that’s coming up in my lectures – what’s the connection between heat and infra-red? You’ve probably seen imagery from ‘thermal imagers’ or infra-red (IR) cameras, usually on police shows, taken from a helicopter as it follows a suspect fleeing down some alley-way at night. You’ll see that ‘hot’ things (like […]
Continue readingClaims on the electromagnetic spectrum
I wrote a couple of weeks ago about the value of electromagnetic spectrum real-estate. It proved quite topical – as I wrote it I had no idea that Stephen Joyce was about to release an emphatic "no" to requests from the Maori Council for rights to the 4G spectrum (See e.g. the TVNZ coverage of […]
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 readingResults of the mobile phone experiment
Well, I have now done themobile phone experiment in a lecture. The question was, is a bucket of water enough to shield the electromagnetic communication between a cellphone and the nearest mast? So, I wrapped my phone in glad wrap (or cling film, for those who don’t live in NZ), put it in a sealable […]
Continue readingGoodbye old technology and hello new
First the new stuff: Judging by the excited twittering of the last day or so, there are a few rather excited people at CERN. http://www.twitter.com/cern . It’s now running and producing collisions at 3.5 TeV per beam. We are well in the realm of new physics. The Higgs boson might feel a little nervous now – it […]
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