Today was my visit to the primary school to talk to the older classes about the solar system, and to supervise my Science Club class while we did experiments with laser diffraction. We measured the diffraction patterns of red, blue, and green laser light through double slits, replicating Young’s seminal experiment which established that light had the properties of waves. We ran out of time to do all of the calculations, but very quickly I got a rough figure of 620 nanometres for the wavelength of the red laser (which actually has a wavelength of 632.8 nm, so we got pretty close). Over the next while I’ll refine the measurements and calculate the other wavelengths too.
It was rainy today in Sydney. At least on the coast. It was dry as I drove towards the school, which is near the coast, and as I came down the hill from the plateau to the coastal strip, it began raining, and was really heavy by the time I got to the school. Unfortunately, we need the rain inland, where the dams are for our water supply.
New content today:
Today was cold and windy. It really felt like winter for once. I went out for lunch and the sky even had clouds in it! They were pretty thick and grey in fact, and I thought it might rain, but the promise of any precipitation turned out to be false.
Besides being a very warm winter, it’s also been extremely dry. We’ve had just 3 mm of rainfall so far this August, and Sydney’s average August rainfall is 80.3 mm. In July we had 43 mm of rain, mostly loaded into the first week, while the July average is 95.7 mm. So we’ve basically had 6 weeks with almost no rain at all. The news tonight reported that Sydney’s water supply dam level is now below 50% – the last time this happened was 15 years ago.
Besides the false promise of rain, the weather was pretty wild. I took Scully out to the dog park, and even though I rugged up in a jumper (sweater for the Americans) and a windproof jacket, it was still nastily cold with the wind blowing off the harbour. While there and chatting with some of the other dog owners, we heard a big crack, and we turned to see that a branch had fallen off the huge Moreton Bay fig tree that we were sitting/standing under (there are wooden benches there for sitting, which many of the owners do). Fortunately, it was on the far side of the tree, and didn’t land on any of us or our dogs. It landed on the street beside the park, narrowly missing someone’s parked car (lucky it didn’t land on that too).
A few of us dragged the branch off the street to clear it for traffic, and I took a photo. It’s not a huge branch, but would certainly have caused an injury if it had fallen on someone, or dented the roof or smashed the windscreen of a car. You can see it’s longer than a car, and it was fairly hefty.
That’s Scully on the right, with the red doggy-jumper. Next to her is Monty, a chihuahua-Jack Russell cross. Up on the street is Scout, a west highland white terrier. As you can see, all the dogs are rugged up for the winter weather!
Also today I contacted Sydney University again to arrange to borrow some lasers and diffraction slits for my next visit to the school where I teach my Science Club class. We’re going to measure the wavelengths of different colours of light! I’ll go in tomorrow to pick them up.
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This morning I had a blood test, and had to go to the pathology place while fasting, so couldn’t eat breakfast beforehand. I like breakfast. I don’t really understand those people who skip breakfast or who don’t feel any urge to have food until lunchtime. I wake up ravenous every morning and am hoeing into a bowl of cereal within about 5 minutes of getting out of bed every day. So having to wait until I walk up the street and wait for half an hour at the pathology centre is torture. Immediately after I left I raced to the nearest bakery to get something to eat.
Back home, I worked on writing annotations for the batch of Irregular Webcomic!s that I’d made over the past few days. This is the final step before publication, and can take most of a day, depending how much research I do and how much I write for each comic. But it’s a good feeling having the batch completed. And now it’s time to start thinking about writing the next batch…
I stayed in for lunch today and made myself bruschetta. I’m trying to use up a bottle of extra virgin olive oil that I got as a gift, before it passes its “best before” date. And also some caramelised balsamic vinegar.
It got me thinking about olive oil. We have extra virgin olive oil, for stuff like bruschetta and salads and those things that everyone says you should use extra virgin olive oil for, because it has a strong “fruity” flavour. And we have the “light tasting” olive oil that everyone says you should use for cooking, because it has a less strong flavour that won’t dominate a dish.
Now, I don’t know if it’s just me, but I can’t taste any difference whatsoever between “extra virgin” olive oil and “light tasting” olive oil. Not just the current brands we have either – I’ve never noticed any difference between any of the brands of either we’ve had over the years. I’m honestly beginning to think this whole “fruity” and “light” olive oil flavours are really just the Emperor’s New Clothes, and a way to make us all buy more olive oil because we “need” to have two different types. They all just taste equally bland and oily to me – none of them have anything that could remotely be called a “strong” flavour that might dominate anything else. Can anyone actually taste a difference between these olive oils?? Or even taste them at all??
And on another note, I took some photos of flowers. This winter in Sydney has been ridiculously warm. Besides flowers everywhere, there are new green shoots and leaves on many of the trees already as well. This is all at least a month early, possibly more. Take a look: magnolias, irises, lavender, azaleas.