By Gregory MonePosted 10.17.2007 at 2:08 pm2 Comments
This extended rubber-burning session was performed in honor of the classic Burt Reynolds movie Smokey & The Bandit, but NASCAR drivers are also prone to peeling out after a victory. So, what's at work here? We asked University of Nebraska physicist Diandra Leslie-Pelecky, the author of a forthcoming book called The Physics of Nascar, to tease out the science in the clip, and she says it's basically a big, loud, smoke-filled demonstration of the law of conservation of energy.
Normally when you step on the gas in a rear-wheel drive car, the front tires roll, and the car goes forward. Here, though, the driver also keeps one foot on the brake. The front end of the car is trying to stay in place by keeping its wheels locked, while the back end is trying to drive forward. Some of the energy the engine produces still goes into moving the car around that parking lot, but a lot of it is also lost to sound and smoke.
The asphalt itself eats away at the tires like sandpaper smoothing out a piece of wood. "You're seeing the person burning off their tires, basically," Leslie-Pelecky says. While this display is pretty impressive, NASCAR drivers produce even more smoke than this adventurous driver because their tires don't have tread. Since the tires are smooth, there's more material in contact with the track, so they burn more rubber, faster.
The final lesson? "If you try this at home," Leslie-Pelecky says, "You'll probably need a new set of tires."—Gregory Mone
Five amazing, clean technologies that will set us free, in this month's energy-focused issue. Also: how to build a better bomb detector, the robotic toys that are raising your children, a human catapult, the world's smallest arcade, and much more.