Last week we had a new oven installed. Our old el-cheapo one that came with the house was never in Karen’s good books. Small, dirty, incapable of getting to a high temperature and generally giving the impression that it was about to die at any moment. Indeed, it did a couple of Christmases ago – […]
Continue readingMonth: May 2013
The ticker-tape car
Somewhere in the Cambridge / Hamilton vicinity is a car with no oil in it. I know this because on the way in to work this morning there was a trail of oil on the road. The damp road surface led to it being very prominent. A splash of oil, being less dense than water, […]
Continue readingUnits – they just don’t go away
One thing that’s become really clear to me in teaching physics is that dimensions and units are not straightforward concepts for students. I might hazard the assertion that they are ‘threshold concepts‘ – ones where grasping what they are about transforms you way of thinking. Most people at least half-understand the idea of units – […]
Continue readingWhat does electricity cost?
I was at a local intermediate school this morning, talking to a group of students about energy. It’s a pretty broad topic, and they were very enthusiastic, meaning I only got through about half of what I wanted, but that’s OK. If it inspires them to go and find things out for themselves, then that’s […]
Continue readingThe bubble raft and lattice defects
After doing the washing up a few days ago, I returned to the sink to find a raft of bubbles had formed on the surface of the water. All the bubbles were roughly equal size, and they had aligned themselves into a close-packed lattice, as the photo shows. (Sorry about the quality of the photo […]
Continue readingYou know you are having a bad day when…
This morning I turned up to give my solid state physics lecture and I realised I was in the wrong place. I’d gone to the lecture room where the Friday lecture is held, not the Thursday one. The trouble is, I had absolutely no recollection of where the Thursday lecture was. Not being a smart-phone […]
Continue readingDon’t miss the eclipse (hee hee)
Friday is the last opportunity to view a solar eclipse in New Zealand for a long time (till 2021 – or 2025 if you don’t count anything of a few percent or lower). I say ‘view’, but the reality is that such a smidgen of sun is going to be covered that you’re going to […]
Continue readingThe sleep machine
I came across this paper while doing a bit of reading about the applications of transcranial magnetic stimulation (TMS). A TMS machine applies pulses of magnetic field to the brain. The rapidly-varying magnetic field induces an electric field (Faraday’s law) and this in turn influences neural activity (but just how and where is an open question). A […]
Continue readingBig and small
Here’s a great interactive website by Cary Huang to give you an idea of how big and small things are. Thanks to Greta Dromgool for pointing me towards it. It covers a whopping 60 orders of magntiude in length – from ten to the power of minus thirty five (the Planck Length) through to 10 […]
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