Monday, March 3, 2014

Experimentation

David C. Baird
Physics at RMC:  The First 125 Years
ISBN 978-0-9919047-0-9
2013
pages 82-85

As part of setting up the new Science and Engineering program at Royal Military College in 1957, we (Tom Hutchison and David Baird) embarked on preparing a Third Year physics laboratory course.  As with all the laboratory courses in the preceding junior year, the course was constructed to follow the traditional pattern in which the students, working in pairs, were provided with detailed instructions for every step of their experiment.  These instructions included all the relevant theory, the setting up of the apparatus (including if necessary, circuit diagrams), the schedule of the measurements, the drawing of graphs and the calculation of final answers.  Nothing was left to the skill or imagination of the student.  The purpose in these ritualized exercises was not clear.  Such was the unquestioned practice that was almost universally followed in those days.

At the end of the 1957-58 academic year, Tom and I decided to pay homage to our stern Scottish heritage of laboratory education and give the students, for the first time, a laboratory examination.  Without thinking, we apparently assumed that in the laboratory courses that were part of all their physics courses in the preceding three years, the students must have learned something of how to actually do experiments.  In addition, thinking to let the students down gently, we chose a simple experiment.  We gave the students a dish-shaped glass "watch glass", a steel ball bearing that could roll in the watch glass, and appropriate measuring equipment for dimensions and time.  A small piece of paper stated that the requirement for the examination was to derive an expression for the period of oscillation as the ball rolled back and forth and make the necessary measurements to derive a value for the acceleration of gravity.

At the time appointed for the examination, the students were admitted and Tom and I confidently strolled around the laboratory, innocently expecting to supervise the busy activity of the students.  Instead, there was complete stillness and profound silence.  After half and hour of total inactivity it finally dawned on us that after three whole years of traditional laboratory courses the students still did not have even the most remote idea of how to conduct an experiment.  Eventually, we wrote the necessary formulae on the blackboard and coaxed the students through their "exam."  It was an enlightening experience for Tom and me.  For the students, it was sufficiently traumatic that one senior retired officer (an ex-Commandant of the RMC) recently accusingly mentioned it to me.

Tom and I were forced to recognize that almost all time spent in our earlier highly structured laboratory classes had been wasted.  The students had no idea of the nature of measurements and their uncertainty, the nature of theoretical models, the significance of graphical analysis of the experimental results, or the nature of the final statement one could make about the experiment or the results.

For the 1958-59 school year, I attempted to construct a syllabus for the Third Year laboratory class to address this.  It was a dismal failure.  After two whole years of following recipes in the preceding labs, the students had no intension whatsoever of actually working to acquire something as esoteric as experimental independence.  It was clear that, like learning a foreign language, experimenting involved basic mental attitudes that would have to be acquired at the earliest possible stages.

I asked Tom if I could have the First Year lab.  This had traditionally contained nothing but experiments that consisted of a series of illustrations of the lecture course material in "recipe book" style.  This we now totally discarded.  The new program consisted of a mixture of lecture material and experimental procedures chosen specifically to illustrate the various aspects of measurement uncertainty, measurement statistics, graphical analysis and the analysis of experimental results.

Reference:

Experimentation, An Introduction to Measurement Theory and Experiment Design (Link)

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