Chicken Joke

A farmer noticed that his chickens were sick, and called in a biologist, a chemist, and a physicist to help diagnose the problem. The biologist observed the chickens, concluding, “I can tell you there’s something wrong with your chickens, but I don’t know what’s causing it.” The chemist took fluid samples from the chickens back to his lab, and returned saying, “I can tell you what’s infecting your chickens, but I don’t know how they got it.” Meanwhile, the physicist had been sitting on the floor, scribbling maddly on several notebooks worth of paper. Suddenly, he jumped up, exclaiming, “I have the answer, but it only works for spherical chickens in a vaccuum.”