I’ve been thinking a bit more about the comment I made yesterday that there used to be a time that physics discoveries were made by people but now we just need to build a machine to do it (the LHC). The major science discoveries, almost by definition, are unexpected and can be very serendipitous. The […]
Continue readingTag: electron
What’s CERN twittering about?
A quick skim of CERN’s Twitter site, www.twitter.com/cern tells me that the LHC is going to be pootling on for the next two years at 3.5 TeV per beam, before it is prepared for running at 7 TeV, starting hopefully in 2014 "…[This] gives the LHC’s experiments a good chance of finding new physics in the […]
Continue readingNegative Resistance
I was having a conversation last week with a student about negative resistances (in an electronics context). These are just as they sound – to send a current from terminal A to terminal B you have to apply a higher potential to terminal B than terminal A. Sounds backwards? Yes – it is. That’s why […]
Continue readingMouse-be-gone (-be-gone)
Here’s some interesting stuff courtesy of the mighty google on yesterday’s post. http://digitalcommons.unl.edu/cgi/viewcontent.cgi?article=1033&context=nwrcrepellants It’s an old (1997) report on ‘electronic’ pest control devices. On ‘electromagnetic’ devices, it comments "Laboratory efficacy tests on the control of Norway rats … indicated definitively that such devices have no effect on feeding, drinking, mating or infestation patterns." Hmmm. […]
Continue readingElectromagnetic Pest Repellent
I saw in the newspaper yesterday an advert for an ‘ultrasonic and electromagnetic’ mouse and rat repeller. That got me interested. The ultrasonic bit seems to be plausible enough – I don’t know much about rodent ear physiology, but I’m willing to believe they can hear sounds at higher frequency to us and to dogs […]
Continue readingElectrical Noise
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 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 readingFluctuations in Earth’s magnetic field
In uncertain times, its good to know there are some things that never change – such as day follows night, my compass needle always points in the same direction, and England will always underperform at the World Cup. Well, scrub the middle one, actually. In our lab, at any rate, there are some shocking variations in […]
Continue readingThe essence of physics
Exams are looming, and I’ve had a constant stream of students coming to me this week asking me questions. One question I’ve had has been asked by two students independently, relating to an example calculation done in a text book. The question goes like this: "I’ve been going through this example, and I get the […]
Continue readingWhat shall I blog about today?
Don’t ask that question. There I was, last night, leaving work, thinking that I had nothing to put on a physics blog, when I turned the key in my car ignition to find an engine that was struggling to give me any power. After going a kilometre or so, it was clear it wasn’t a […]
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