Thursday, September 23, 2004
Swimming in syrup is as easy as water
It's a question that has taxed generations of the finest minds in physics: do humans swim slower in syrup than in water? And since you ask, the answer's no. Scientists have filled a swimming pool with a syrupy mixture and proved it.
"What appealed was the bizarreness of the idea," says Edward Cussler of the University of Minnesota, Minneapolis, who led the experiment. It's a question that also fascinated his student Brian Gettelfinger, a competitive swimmer who narrowly missed out on a place at this summer's Olympic Games in Athens.
Cussler and Gettelfinger took more than 300 kilograms of guar gum, an edible thickening agent found in salad dressings, ice cream and shampoo, and dumped it into a 25-metre swimming pool, creating a gloopy liquid twice as thick as water. "It looked like snot," says Cussler.
The pair then asked 16 volunteers, a mix of both competitive and recreational swimmers, to swim in a regular pool and in the guar syrup. Whatever strokes they used, the swimmers' times differed by no more than 4%, with neither water nor syrup producing consistently faster times, the researchers report in the American Institute of Chemical Engineers Journal1....