Demolition Demos (Sort of)

There were so many cool science tricks and demonstrations packed into the three-hour lecture that I can’t mention them all. I’ll just try to go into depth on a few instead.

Before I get into the two highlights for me, I want to add some honorable mentions. One standout was when he used a Tesla coil to make a variety of gasses glow some very pretty colors. (with the side effect of making him look like he was feeling the power of the dark side) In another great one, he showed how different people have different current thresholds where they can’t release their grip on an electrode. And of course there was Dr. Andersen’s sulfur hexafluoride-fueled stint as a movie villain. But on to my favorites.

The first here is also the first one he performed. He brought out a Jacob’s Ladder, which, for the uninitiated, is two long electrodes in a skinny V shape, which when hooked up to a high voltage power supply, create a rising arc of plasma. A funny note about Jacob’s Ladders: their name itself is a bit of a morbid joke. They’re named after the ladder leading up to heaven that Jacob, of biblical fame, saw in a vision. Because if you touch a Jacob’s Ladder, you don’t need to worry about climbing any stairways. You’re taking the express route to the afterlife. So you can imagine that when Dr. Svedrup casually stuck two wads of gun cotton, a cousin of TNT and nitroglycerin, on the ladder’s prongs and told the people in the front row to stand back, everyone was a bit worried. High voltage and explosions are both awesome when viewed from a safe distance, but when they’re combined, the whole safe distance thing gets even more important. And we weren’t disappointed when he flipped the switch. The arc shot up towards the explosive, and the instant it made contact, the gun cotton vanished, accompanied by a huge bang and a momentary fireball flash.

When he was playing around with the Tesla coil, he brought out a neon sign. Like the other lights he held near the coil, it lit up brightly. But then he passed out little lens-looking things called diffraction gratings. Looking through a diffraction grating, which bends different frequencies of light differently, we could see that it didn’t just look like a smooth rainbow, like the other lights did when it was strained on them. There were only a few, well defined, monochrome images of the sign. 

Photo Credit – Ellie Fang (Associated Post)

As the good doctor revealed to us, each of these corresponded to a peak in neon’s emission spectrum, a direct result of the way atoms emit only discrete frequencies of light in quantum mechanics when their electrons lose energy. It may have been more low-key than many of the other experiments, but, in my nerdy opinion, it was by far the coolest. Evidence of quantum mechanics dropped right in front of us by way of a neon sign and some cheap cardboard-wrapped lenses! Now that’s a science demonstration.