NPL is having an ‘Open house‘ on Tuesday May 17th from 2:00 p.m. until 8:00 p.m., and I have been asked to prepare a temperature exhibit in my lab.
Unfortunately this involves more than simply opening the doors and chatting to whoever turns up.
The first thing is to work out what to show? I have selected three types of thermometry that people might find intriguing.
- Thermal Imaging: which measures the infra-red light emitted by objects
- Phosphor thermometry: which measures how rapidly the fluorescent light decays from a material painted onto a hot surface.
- Acoustic thermometry: which measures the speed of sound in a gas.
Next we need to figure out how to explain what is going on and why it is worthwhile researching these techniques. This typically involves a combination of posters (which must be designed and printed) and demonstrations (which must be meaningful: neither overly complex nor overly simplistic).
Then we need to make sure it is safe for everyone and convince our internal Health and Safety team that this is so! This involves thinking about all the ways in which somebody might come to harm, listing them, and then saying what we are going to do about them.
I’ll write more in the coming days, but last night I tried out one of the demonstrations for acoustic thermometry which involves sending sound pulses along tubes.
To allow people to appreciate the speed of sound, I wound 50 metres of yellow plastic tube around the lab (See the picture at the top of this article). People can tap on a drum skin and hear the sound come out of the tube around a seventh of a second later.
It’s is a simple demo but very pleasing. What is astonishing is that we can measure that time delay with an uncertainty of less than a millionth of second and use the result to estimate the average temperature along the tube.
This kind of ‘tube’ thermometer isn’t very accurate, but the lab will also have a demonstration of the most accurate thermometer in the world. Ever! Oh yes, and I will be giving a couple of talks during the day too.
Overall it involves a colossal amount of effort from hundreds of people around the lab. I know that my productivity will plummet for the preceding fortnight, not least because we have to put away all the stuff in the lab which might be inadvertently damaged!
The day itself is usually very pleasant, but exhausting, and if you can make it, it would be lovely to see you. It’s all free, but you do need to register.