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Originally posted by skiracer
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To all who believe there is only one right answer:A young man was being interviewed for entrance to Cambridge college to studyphysics. He was asked among other things, the following question: How would you measure the height of a skyscraper using a barometer?The candidate replied as follows: Take a very long piece of string. Tie one end of it to the barometer. Keeping hold of the other end, dangle the barometer off the roof of the skyscraper until it reaches the ground. Then the length of the string plus the length of the barometer equals the height of the skyscraper. The interviewing tutors did not accept the answer, and thecandidate was rejected. But he appealed to the university authorities onthe grounds that his answer while perhaps unorthodox, was undeniably correct.It so happened that professor Iza Conman of Michigan was in Cambridge at thetime as visiting professor, and he was asked to arbitrate in the dispute. Heasked the candidate to see him, and gave him five minutes to reply to the samequestion in a way that showed knowledge of the basic principles of physics.The young candidate was silent for three minutes. Conman warned him that thetime was running out. "The problem is," said the candidate, "I've thought ofseveral possible answers, but I can't decide which is the best.""One minute," said Conman. "Well," said the candidate, "You could take thebarometer to the roof of the building and drop it, using a stopwatch to measurethe time the barometer took to reach the ground. If this t is time, and theacceleration due to gravity is g, then the height of the building would begt/2. (editor's note: neglecting friction and lift.) But then you've got anex-barometer."If the sun is shining, you could measure the length of the barometer, thelength of its shadow, and the length of the skyscraper's shadow. Then it'sjust a matter of proportional arithmetic to work out the height of the sky-scraper."If you want to be highly scientific you could tie a piece of string to thebarometer and make it swing like a pendulum, first on the roof and then on theground. Then you could work out the acceleration due to gravity on the roofand on the ground from the period of the oscillation of the pendulum. Fromthis difference you can determine the height of the building."Or you could walk up the stairs with the barometer and a pencil, marking offlengths of the barometer as you go. Adding them up at the end.""If you want to be boring you could measure the air pressure on the roof andat ground level, convert millibars to meters and get the height of the sky-scraper from that."But in the end the best method would probably be to knock on the janitor'sdoor and say, `Look; if you tell me how high this building is, I'll give youthis lovely new barometer.'"
Sounds like a "tuft" race...Doug(IIC)
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