morguefile.com

It's Physics, like "Fun" science...  "And there are lots of turns," adds 14-year-old water park enthusiast Benn Calhoun. "As you go down around some of the bends, you think you're going to go over the edge, but you don't. And that's the best—when you think you're going to go over, but you don't."   How it is done: