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 […]
Continue readingTag: light
Diffraction
If you’re like me, you’ve been mesmerized by the colours created by reflections from a DVD or CD. The discs do a great job of splitting the illuminating ‘white’ light of your home light-bulbs into its constituent colours. But unlike a prism or raindrop, which achieve this effect through refraction (blue light travels more slowly […]
Continue readingHow fictional is fiction?
Having watched The Prestige on Sunday night I feel that there should be lots of bloggable material in it, but I can’t quite put my finger on anything. For those who haven’t seen it, or read the book, it concerns a couple of rival magicians who are obsessed with out-doing each other and pulling off […]
Continue readingLet there be light
Last night we were plunged back into the 19th century by a power cut. No electric cooker, no lighting, no television. Out came the candles. We were only saved from total historical immersion by a fully-charged laptop which got used as a DVD player for the evening (and gave a fair bit of light too). It’s amazing […]
Continue readingClever lenses
I’ve just bought a new pair of glasses. The prescription is a little different from my old pair, meaning that although everything is slightly sharper the world seems to curve downwards a bit towards my right. That’s just my brain getting used to the new way in which the world is projected onto my retina – […]
Continue readingMeasuring the speed of light
Earthquakes are not the only thing that can cause a building to move. Simple expansion and contraction as a building heats and cools can move walls around. Not so you’d notice with the naked eye, but certainly noticeable if you have mirrors attached to the walls to guide a laser beam around a lab. That’s […]
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 readingMore physics with aluminium foil
I gave a talk to the Junior Naturalists in Hamilton last Friday. It had some similarity to the talks I gave in June to the Osborne Days (year 12 and 13 school students), but I needed to change a few things because 1. The audience was younger, and 2. I wasn’t prepared to cart voluminous apparatus […]
Continue readingInfra-red and heat
Here’s a bit of physics that’s coming up in my lectures – what’s the connection between heat and infra-red? You’ve probably seen imagery from ‘thermal imagers’ or infra-red (IR) cameras, usually on police shows, taken from a helicopter as it follows a suspect fleeing down some alley-way at night. You’ll see that ‘hot’ things (like […]
Continue readingLots of flashing LEDs
A sure-fire way to increase the value of any piece of electronic equipment is to add some superfluous flashing red, yellow and green LEDs to it. (Light Emitting Diode.) They serve no use, but their presence is somehow comforting (especially in sci-fi films) and gives the impression that the equipment is busy doing something useful. There […]
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