Have you ever thought why water is difficult to move through? What property does it have that air doesn’t, that makes it an effort to get anywhere in it? The answer is utterly straightforward, but it is worth saying: it is simply more dense than air. If you want to move through it, you’ve got […]
Continue readingYear: 2009
Swimming pool physics
It’s summer, and for me that means the university’s 50 metre outdoor swimming pool is open. Lots of lunchtime lengths, dodging the morons who can’t cope with the concept that lanes are for lane swimming, rather than playing ball games. There’s a lot of physics that goes in with swimming. Hydrodynamics, the study of how […]
Continue readingThunderbolts and lightning, very very frightening
I guess we all have our own utterly irrational fears. One of mine is needles. It’s not that they hurt, because they don’t; rather it’s the concept that causes me to shudder at the prospect of a blood test. Sticking bits of metal into my body and sucking out the contents? I don’t think so. […]
Continue readingAdd one tablespoon of golden syrup…
One tablespoon? Is that all? Depends on the recipe, I guess. But does anyone know exactly how much one tablespoon actually is? The answer, which I found out at the weekend, demonstrates exactly why the world needs physicists. According to the instructions with my wife’s new breadmaker, an Australian tablespoon is different from a […]
Continue readingLevitation
Last Thursday while browsing a popular NZ-based website an article caught my attention: ‘Scientists learn to levitate objects’. Images from Harry Potter films flashed before my eyes, and I thought this had to be something worth checking out. And it was, for two reasons. First, because the article is a surprisingly accurate piece of science […]
Continue readingThe second law of thermodynamics
So now you know the first law – what’s the second law? This one is a whole lot easier to define since you don’t need to fret over what exactly energy IS, and, historically speaking, it was understood long before the first law. (It is relegated to being the second law of thermodynamics since the first […]
Continue readingThe first law of thermodynamics
I’ve used the word ‘energy’ a lot in recent posts (like yesterday’s), but haven’t really said what it is. We all have some idea of what energy means – it’s a resource you need to do something useful, such as propel a car, or play a video game, heat your house or power refigerator. (This […]
Continue readingIt’s cold out there
Having lived in Waikato for five years now, I’d forgotten what cold temperatures feel like. I’ve just got back from Christmas in the UK (explains lack of blog entries) where I was reminded what winter is like: dark and cold. Minus 9 feels pretty nasty, but, how cold is that really?
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