The professors of mathematics and physics were staring away at the flag pole in front of the college building. The professor of English walking by asked, 'What seems to be the problem?'

We, said the professor of mathematics, were wondering how to measure the height of this flag pole. The professor of English quickly unscrewed the pole from its moorings, laid it on the ground, whipped out a measuring tape, measured it, and said, It is exactly 20 feet long, and walked away smoking his pipe. Looking at the English professor's receding back, the professor of physics remarked, Smart Ass. We wanted to know the height, and he tells us the length!