The Cardiff Science Festival starts on Monday, and I still haven’t had the time to prepare. Thank goodness I have a week before my set.

It’s the first time that I will be standing in front of a group of people and talking to them for longer than 25 minutes, and about something that wasn’t a requirement for my degree.

When I was asked to do it, initially I declined it. I didn’t feel ready to stand up in front of people and tell them all about something I found super cool. Not just tell them about it, but make it interesting, funny in places, and educational. It’s such a daunting task being asked to teach people; giving them knowledge. In a way I’m honoured that the organisers thought I would be good enough to do so.

Whenever I have been to watch people give talks, I find that the ones with demonstrations are the best. They invite the audience in to your little world, and show them something they (hopefully) haven’t seen before. It’s very exciting, learning something new. And if the person teaching you finds it exciting, it definitely comes across.

My physics teacher at school was one of those. He loved teaching, and you could tell he loved physics. I always enjoyed his lessons; he would do the best class experiments. We would sometimes pretend we were particles, bumping into each other, trying to see the world from their point of view when undergoing Brownian Motion. We built rockets, made parachutes for hard-boiled eggs, exploded things, and played with the fire extinguishers. It’s because of him that I studied physics.

So, for my talk I want to use a demo, two actually. It’s difficult to know what makes a good demo, especially if you’ve never designed one yourself. What is it that makes a good demo? I want to explain that a moving body in water is more stable than a still one, without using water. I have some ideas, one good one I think; I hope it works. I guess I won’t know until I try it out. I’ll let you know how it goes.

Go to the orginal article here or listen below