Physics Stop

When the power goes off

Marcus Wilson Aug 20, 2019

This morning we woke up to discover  a power cut. This meant: No electric kettle. We do have a gas stove, however, which we could light with the help of matches (the automatic ignition relies on mains power.) So we did eventually get some hot drinks. No toaster. No microwave. No hot toast, no porridge. Back to the Weetbix. No … Read More

Student evaluations of teaching effectiveness tell us nothing about teaching effectiveness

Marcus Wilson Aug 12, 2019

I thank my colleague Chris Lusk for bringing this paper by Uttl, White and Gonzalez to my attention. Many universities and polytechnics acquire Student Evaluation data on courses and teacher quality at the end of a course. There are different ways this can be done – here at The University of Waikato students are asked (online) a series of questions … Read More

The lying dashboard

Marcus Wilson Aug 07, 2019

How accurate are our car speedometers? That’s well discussed., e.g. on this AA question forum.  If the ‘expert’ here is correct, your car speedometer could over-read by as much as 10% + 4 km/h (which is quite a bit – if you are doing 45 km/h it might read 54.5 km/h, or if you are doing 90 km/h it … Read More

Quantum cryptography

Marcus Wilson Jul 30, 2019

I was reading last week a children’s book about “Secret codes”.  You probably know the kind of thing I’m talking about – substituting one letter for another, or a squiggly shape for a letter, rearranging letters, and so on. Fun things to do, but not the basis of modern cryptography. However, the book didn’t just stop at these codes, but … Read More

Alice the camel

Marcus Wilson Feb 05, 2019

As we drove on a family outing at the weekend, we sung “Alice the camel”.   For those who don’t know it, it goes like this (to the tune of “Dem Bones”): “Alice the camel had five humps; Alice the camel had five humps; Alice the camel had five humps; so go, Alice go! Alice the camel had four humps… Alice … Read More

In praise of fixable appliances

Marcus Wilson Dec 17, 2018

Last week saw the first ‘fault’ on our washing machine. We’ve had this particular one for nine months, and with a baby and young boy in the house it is well used. When I went into the laundry to empty the machine I found the cycle had not finished as I had expected. Instead, the machine was flashing an error … Read More