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If you are interested in using problems like this one to make a point, you
might want to know about a video I use. I encountered a version of this
story in  "Why didn't I think of that?" which is a video on creative
problem solving. It was published by Learning Seed in 1990. Their address
is 330 Telser Road, Lake Zurich, IL, 60047. I don't have a phone number.

Maggi Miller
Austin Community College




>>From: Barak Rosenshine <[log in to unmask]>
>>Subject: Not a true story
>>A not true story:
>>
>>Some time ago I received a call from a colleague. He was about to give a
>>student a zero for his answer to a physics question, while the student
>>claimed a perfect score. The instructor and the student agreed to an
>>impartial arbiter, and I was selected.
>>
>>I read the examination question:
>>"SHOW HOW IS IT POSSIBLE TO DETERMINE THE
>>HEIGHT OF A TALL BUILDING WITH THE AID OF A BAROMETER."
>>
>>The student had answered, "Take the barometer to the top of the building,
>>attach a long rope to it, lower it to the street, and then bring the rope
>>up, measuring the length of the rope. The length of the rope is the height
>>of the building."
>>
>>The student really had a strong case for full credit since he had really
>>answered the question completely and correctly! On the other hand, if full
>>credit were given, it could well contribute to a high grade in his physics
>>course and to certify competence in physics, but the answer did not confirm
>>this.
>>
>>I suggested that the student have another try. I gave the student six
>>minutes to answer the question with the warning that the answer should show
>>some knowledge of physics. At the end of five minutes, he had not written
>>anything. I asked if he wished to give up, but he said he had many answers
>>to this problem; he was just thinking of the best one.
>>
>>I excused myself for interrupting him and asked him to please go on. In the
>>next minute, he dashed off his answer which read: "Take the barometer to the
>>top of the building and lean over the edge of the roof. Drop the barometer,
>>timing its fall with a stopwatch. Then, using the formula x=0.5*a*t^^2,
>>calculate the height of the building."
>>
>>At this point, I asked my colleague if he would give up. He conceded, and
>>gave the student almost full credit. While leaving my colleague's office, I
>>recalled that the student had said that he had other answers to the problem,
>>so I asked him what they were.
>>
>>"Well," said the student, "there are many ways of getting the height of a
>>tall building with the aid of a barometer. For example, you could take the
>>barometer out on a sunny day and measure the height of the barometer, the
>>length of its shadow, and the length of the shadow of the building, and by
>>the use of simple proportion, determine the height of the building."
>>"Fine," I said, "and others?"
>>
>>"Yes," said the student, "there is a very basic measurement method you will
>>like. In this method, you take the barometer and begin to walk up the
>>stairs. As you climb the stairs, you mark off the length of the barometer
>>along the wall. You then count the number of marks, and this will give you
>>the height of the building in barometer units."
>>
>>"A very direct method."
>>
>>"Of course. If you want a more sophisticated method, you can tie the
>>barometer to the end of a string, swing it as a pendulum, and determine the
>>value of g at the street level and at the top of the building.
>> From the difference between the two values of g, the height of the building,
>>in principle, can be calculated."
>>
>>"On this same tact, you could take the barometer to the top of the building,
>>attach a long rope to it, lower it to just above the street, and then swing
>>it as a pendulum. You could then calculate the height of the building by the
>>period of the precession".
>>
>>"Finally," he concluded, "there are many other ways of solving the problem.
>>Probably the best," he said, "is to take the barometer to the basement and
>>knock on the superintendent's door. When the superintendent answers, you
>>speak to him as follows:
>>
>>'Mr. Superintendent, here is a fine barometer. If you will tell me the
>>height of the building, I will give you this barometer."
>>
>>At this point, I asked the student if he really did not know the
>>conventional answer to this question. He admitted that he did, but said that
>>he was fed up with high school and college instructors trying to teach him
>>how to think.
>>
>
>
>
>*********************************
>Norman A. Stahl, Acting Chair
>Department of Literacy,
>Intercultural and Language Education
>GH 223c
>Northern Illinois University
>DeKalb, IL  60115
>
>Telephone:
>(815) 753-9032 {office}
>(815) 753-8563 (FAX)
>
>Email: [log in to unmask]