Archive for May 17, 2011

Cute Physics Problem

Posted in Cute Problems, The Universe and Stuff with tags , on May 17, 2011 by telescoper

I heard this nice physics problem today so I thought I’d try it out on here. You will probably be able to find the answer on the net somewhere but please try to figure it out yourself before doing so!

There are two identical chambers, A and B containing identical metal balls which begin the experiment at the same temperature. Apart from the balls, each chamber is a perfect vacuum and has thermally conducting walls at a lower temperature than the ball it contains.

In A the ball is resting on the floor, which is made of material which is a perfect thermal insulator.

In B the ball is hanging from the ceiling by a piece of light inextensible string, not touching the floor. Both the string and the ceiling are also made of perfectly insulating material.

Which ball cools down faster?

Please put your answer through the poll here. When enough people have voted, I’ll tell you the answer…


Rainbow over Cardiff

Posted in Uncategorized with tags , , , , , on May 17, 2011 by telescoper

Nice to see the Rainbow Flag  flying at the Cardiff City Council building this morning..

This is in recognition that today, May 17th, is International Day Against Homophobia, or IDAHO for short. Please remember that although attitudes in the UK are much more enlightened than they were only a few years ago, homophobic violence still happens with distressing frequency. And in places such as Uganda, where a bill has been tabled calling for homosexual acts to be punished by the death penalty, matters are even worse…

If you’re wondering why May 17th was chosen for this, then I can tell you that it’s to commemorate May 17th 1990, which is when the World Health Organisation removed homosexuality from its list of “mental illnesses”.


Old Boy Network

Posted in Columbo with tags , on May 17, 2011 by telescoper

It’s only after spending what seems like weeks catching up after my short holiday that I realise I’ve forgotten to post the update that probably most people care about, i.e. my old moggy Columbo.

Well, although he’s not getting any younger he’s still doing OK. I had to make use of the services of a petsitter while I was away (both at NAM and then on holidays). It turns out the lady who usually comes wasn’t available all the time so I had two different people coming to the house at various times. His support network is becoming extensive.

He is of course pretty old now – he was 17 in March – and he’s showing quite a few signs of age. He has been suffering from arthritis in his legs for a while, but the medication seems at least to have stopped it getting worse. He still has a bit of a struggle sometimes getting up and lying down but the discomfort obviously doesn’t last too long. If it gets to the point where he’s in pain all the time then I’ll have to think very hard about what to do.

Despite this ailment (and his continuing diabetes) he still seems happy enough to potter about in the garden in between lengthy snoozes, more often than not on my bed. He’s also still got a healthy appetite. The only times he’s ever been off his food have been when he was really ill, so as long as he’s eating I reckon he’s basically OK. That’s why I don’t mind him cadging for snacks, as is his wont..

Columbo’s basically a friendly old chap and there are occasions when he clearly enjoys having other people around. At other times, though, increasingly frequent now, he clearly prefers his own company and goes off on his own somewhere. I know him well enough not to bother him when he’s in that mood. Actually, Columbo and I are pretty similar in that craving for solitude. We old boys like to keep ourselves to ourselves.