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Maggie-
You are a font of information and good suggestions.  Keep up the good
work!
Helen Sabin
Long Beach California City College

Maggi Miller wrote:
>
> 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]