Well, looks like winter has finally arrived here. There’s not much worse weather-wise than having a clear night with the cloud rolling in just as the sun rises. The clear night lets the temperature drop, as the ground radiates away more energy than it receives from the atmosphere and surrounding objects, and then the clouds […]
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Some thoughts while stuck in traffic
Monday morning was one of those strange days where for some non-obvious reason there was far more traffic than normal. Maybe there had been an accident somewhere, or there was some event on, but, for whatever reason, it took nearly half an hour to crawl through the Hillcrest roundabouts. All that start-stop on the car […]
Continue readingIs it cold enough yet?
This week has seen some icy mornings in Cambridge – a reminder that we are sliding into winter. Our heat pumps have been going, especially first thing in the morning to warm the place up a bit, and the cat has relocated his primary sleeping spot from a chair by a window to a rug closer […]
Continue readingVirga
I learned a new word today: virga. It was used in a short article in one of the Sydney newspapers, discussing yesterday’s weather. Virga is simply precipitation that evaporates before it hits the ground, and we had some here yesterday. So it was raining, but we didn’t get wet. Virga can rapidly cool the air […]
Continue readingMysterious power generation
One consequence of being a physicist is that you can’t go anywhere without seeing physics calculations that need doing. I’ve just been to our library hunting down books on the medical technique of transcranial magnetic stimulation (TMS), which was an interesting exercise in itself, since one textbook I found also has a chapter on homeopathy. […]
Continue readingConvection and continuity
With the coming of the colder evenings, we’ve had our new heat pump going. It’s quite a powerful beast, as it has a large volume to heat, and it comes with a plethora of different settings – temperature, fan speed, air flow angle and so forth. It’s taken some experimentation to get some decent settings […]
Continue readingDumping light into space
Actually, I’ve been thinking a bit more about the 200% efficient LED I described last time. Maybe it can be a solution to global warming after all. The LED converts heat to light. Now, if one were to direct the light upwards, through the atmosphere and into space, it would escape the earth. Sure, it […]
Continue readingA solution to the world’s energy problems?
A student of mine has drawn my attention to this article. (Full article in Physical Review Letters here, a more accessible summary of it in Physics World here.) It describes a light emitting diode (LED) that has a greater than 100% efficiency at converting electrical power to light. That is, put 30 picowatts of electrical […]
Continue readingGetting the facts straight
On Saturday night my wife and I went down to Te Awamutu to watch ‘Sherlock Holmes’ – there being no cinema in Cambridge 🙁 It was a moderately naff piece of film – more James Bond than Sherlock Holmes – though quite suitable for some mindless Saturday night entertainment so long as you were prepared […]
Continue readingKeeping it cold
One of our recent Christmas gifts was an ice-cream maker. It’s been very welcome, what with all those long hot sunny days we haven’t had. Making ice-cream is pretty straightforward. Just bung in the ingredients and stir the mixture while having it freeze. That’s what the machine does. Stirring makes sure large ice crystals don’t […]
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