While waiting for my aged computer to boot-up on my return to work this morning, I was skimming through November’s Physics World magazine, and noted an obituary to Rudolf Mossbauer. He is best known in the physics world for observing ‘resonance absorption’ of gamma rays, and then developing the technique of Mossbauer spectroscopy. When a […]
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Why are radio telescopes so big?
It’s great to hear that NZ is an integral part of the Australasian bid for a giant radio-telescope network. The Square Kilometre Array promises to produce some great images of southern skies in the radio frequency band. Radio waves are part of the electromagnetic spectrum, just like light waves, and can be used to provide […]
Continue readingMomentum conservation
It’s mid-semester break here at Waikato so I have time to breathe and get back to things other than teaching, such as seeing what the PhD students are up to. Yay. But, here’s a comment about what I was talking about last week with the first year students: conservation of momentum. If you look in […]
Continue readingFriction: Stick or Slip?
Going back to my last entry on the sliding car, it’s worth commenting a bit more on the nature of friction here. When a car goes round a corner, what prevents it from sliding is the friction between the tyres and the road. Tyres are unsurprisingly designed to be able to give a high frictional […]
Continue readingSonic anemometer
One thing we’ve noticed with our new house is how variable the background noise is. We now live within earshot of State Highway One and we can hear the distant rumble of trucks and other vehicles on it. The noise isn’t large – and it’s amazing that after just three weeks in the house we […]
Continue readingThe wonderful logarithm (or blog on log)
I’ve been marking a couple of student assignments today. I won’t go into the details, but as part of it they had to process some data and plot some graphs. The graphs showed values that varied considerably – some thousands of times bigger than others. I had expected (assumed = bad move) that the students […]
Continue readingSpeed of sound
On Sunday I went to the Magic – Mystics netball game at Mystery Creek in Hamilton. It was a game that both teams did their very best to lose, in the end the Magic were more dedicated to this cause than the Mystics, and cunningly let them sneak a winning goal in the last few […]
Continue readingLearning outcomes
This week I’ve had three fairly lively discussions about learning outcomes in our university papers. (It’s well blogged already – e.g. here, but I’ll add some things to the mix). The concept is hardly new, but it is only just being given a really wide profile here at Waikato. Although many individual teachers, and many […]
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 readingSound proofing by closing a door
We’ve had a couple of fire alarms in the last week. Both false alarms, which is good. We still however pile out onto the grass in front of the Faculty of Science and Engineering and time how long it takes for the fire engines to arrive and bet on whether the Hamilton City-based crew will […]
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