Saturday, November 19, 2005

Don't Tip a Cow, Man

Growing up in Cow Hampshire, I was familiar with the idea of cow tipping, but never knew anyone who actually did it. And now I know why: it's not physically possible:
Margo Lillie, a doctor of zoology at the University of British Columbia, and her student Tracy Boechler have conducted a study on the physics of cow-tipping.

Ms Boechler, now a trainee forensics analyst for the Royal Canadian Mounted Corps, concluded in her initial report that a cow standing with its legs straight would require five people to exert the required force to bowl it over.

A cow of 1.45 metres in height pushed at an angle of 23.4 degrees relative to the ground would require 2,910 Newtons of force, equivalent to 4.43 people, she wrote.

Dr Lillie, Ms Boechler’s supervisor, revised the calculations so that two people could exert the required amount of force to tip a static cow, but only if it did not react.

“The static physics of the issue say . . . two people might be able to tip a cow,” she said. “But the cow would have to be tipped quickly — the cow’s centre of mass would have to be pushed over its hoof before the cow could react.”

Newton’s second law of motion, force equals mass multiplied by acceleration, shows that the high acceleration necessary to tip the cow would require a higher force. “Biology also complicates the issue here because the faster the [human] muscles have to contract, the lower the force they can produce. But I suspect that even if a dynamic physics model suggests cow tipping is possible, the biology ultimately gets in the way: a cow is simply not a rigid, unresponding body.”

Another problem is that cows, unlike horses, do not sleep on their feet — they doze. Ms Boechler said that cows are easily disturbed. “I have personally heard of people trying but failing because they are either using too few people or being too loud."

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