Thursday, June 18, 2009

9/11 conspiracy theory, thermite

I was thinking about buying some flares off this guy at a yard sale. He was wearing a hat that looked like this:

I wondered aloud about what the flares were made of. The ensuing conversation went something like this:
Guy: "They're made of thermite. Same thing they used to bring down the twin towers."
Me: "Oh yeah?"
Guy: "Totally dude. They found molten iron at ground zero. Molten iron, I shit you not. That stuff melts at 1500 degrees Celsius."
Me: "Well, that makes sense, a plane full of jet fuel crashed into the building."
Guy: "No, it doesn't make sense man. Jet fuel burns at 1000 degrees Celsius. It couldn't possibly have melted the iron. Thermite, that's what did it."
Me: "Hhhhmmmm. I'm sorry, but I don't think jet fuel burns at any specific temperature. I believe it depends on the rate it burns and how fast the heat is carried away."
Guy: "No way man, you should look it up."
Me: "Okay."

Friday, June 5, 2009

on the importance of being earnest about oxygen

Last year in lab, this guy got burnt semi-badly when his oil bath caught fire (actually this story has the odd quirk that I never saw the guy, so i don't know how badly he was hurt, but I can promise you he exists). Actually oil bath fires are not so dangerous, but how you extinguish them can be really dangerous. The molecule that explains why this is so is oxygen. Before I explain, watch this video to see how bad oil fires can get: