Getting students to grapple with the fundamentals was the defining characteristic of his teaching
Prof. J. A. Gunawardena (Prof. G) – ‘Gunda’ to his friends and ‘Kalu Gunda’ to irreverent undergraduates –passed away recently at the age of 83 after a brief illness. Prof. G was an institution in the Peradeniya Engineering Faculty (EFac), not to mention the entire university. There were very few in the University of Peradeniya who had not heard or come across him. His stentorian voice pervaded the lecture halls, labs, and the corridors of the EFac.
I first encountered Prof. G in 1972 when he came to teach the ‘Electronics’ component of the Applied Electricity course module (which was compulsory for all undergraduates). He walked up to the blackboard and drew a ‘diode’ and an alternating current waveform at the input, and then told us to draw the output waveform. We hadn’t a clue as to how to set about this task and Prof. G walked around the class with a mischievous smile playing upon his dusky features, no doubt amused by the bemused expressions on our faces. We, who had been used to ‘one way communication’ when attending lectures did not know how to deal with this situation.
Getting students to grapple with the fundamentals of a subject was the defining characteristic of Prof. G’s teaching. Unfortunately, this did not correspond with what most undergraduates (engineering or otherwise) expect from a lecturer. The average student wants to be able to take down a clear note which can be used to study for exams.This was rarely possible with Prof. G’s style of teaching and the result: considerable ‘casualties’ in the subjects he taught, particularly among students who had little or no interest in electrical engineering.
Later, I came to realize that Prof. G’s lectures were not just fundamentals-based but also, particularly in the final year when he taught Digital Electronics and Control Systems, were really a commentary on the topics. This necessitated coming prepared for the lecture, another thing undergraduates rarely do. I remember him saying when he was introducing us to ‘Worst Case’ design of circuits, that one cannot simply assume the nominal value of a component required for a design (for example, assuming that, what is referred to as a 100 Ohm resistor in the marketplace will have a measured resistance of 100 Ohms). He pointed out that if you purchase such a resistor, its actual value will be either close to 90 or to 110; the reason being that component values have a ‘tolerance’ of say 10% and, when the actual value happens to be close to 100, the manufacturer will classify these as ‘Precision Resistors’ and sell them at ten or twenty times the price of ordinary resistors. For the first time we were made aware of the importance of incorporating commercial considerations into engineering analysis. What Prof. G was trying to get across to us was that if you designed something with an exact nominal value in your calculations, you would end up with a product costing ten or twenty times more than it should. This is hardly what a long-suffering public expects from engineers who are supposed to be capable of doing something for one rupee which a fool can do for two.
Prof. G went on to explain that if a component parameter can be anything between 90 and 110, the analysis would have inequalities instead of equations. Now, to minimize something, say the cost of a product, the presence of inequalities requires the mathematical firepower of nonlinear programming, a field most engineers are not overly fond of. Prof. G recognized this fact of life and showed us how to avoid such mathematical complications by creatively identifying and using situation specific data. Creativity development is the “in” thing in this day and age and I understand many universities have course modules devoted to this. But, here was Prof. G, 45 years ago, teaching us how to be creative in a real practical way.
Precision in engineering was an obsession with Prof. G. Now, when undergraduates are required to perform calculations necessary to design some artifact which will not be constructed (e.g. a bridge or rooftruss), there is considerable temptation to take shortcuts or fudge the calculations. However, if the item in question is to be actually made and tested, the result of fudging your calculations, particularly in electrical engineering, can quite literally be an explosion. A few of my batchmates found this to their cost, and it was a miracle that the lab did not go up in flames after their exploits. In particular, two batchmates forming a project group blew up transistors with such monotonous regularity that they were nicknamed the “thermocouple”! After observing the “fireworks” in the lab, Prof. G prefaced his next lecture with a comment typical of him: “You may fool lecturers, examiners, and other human beings; but you cannot fool the Laws of Nature!”
Prof. G’s integrity was unassailable. He believed and lived the hoary adage, “Because Right is Right to follow Right were Wisdom in the Scorn of Consequence” - notwithstanding consequentialist theories in ethics! If students failed his paper because they had not studied properly, that was their problem, and he would never alter his evaluation. ‘Standardization’ was a word that did not exist in his vocabulary. And even in other spheres, such moral values were manifest in the decisions he took. I am not sure whether this story is apocryphal or not, but it appears that when he passed his BScEng with first class honours, it was not he who had come first in the batch. But Prof. G was awarded the scholarship to read for the PhD. It is said that Prof. G had foregone the scholarship saying that his batchmate who had come first in the batch should be the awardee. This selfless decision would undoubtedly have delayed his postgraduate qualifications.
When Prof. G went on sabbatical leave we, his final year students, went to his home to see him off. In the course of conversation he suddenly asked, “What is the definition of a Second Class?”and then proceeded to answer his own question: “A Second Class is what you get when you have not studied hard enough to get a First!”
My last personal encounter with Prof. G was in the electrical lab. He walked up to me and gave me a report of mine he had evaluated. From the corner of my eye I could see that he had awarded seven marks out of ten. But the figure seven had the lower case letter ‘c’ which, apparently, stood for ‘conditional’. Then he turned to me and said, “I do not expect ‘Good English’ from you. There are very few people in this country who use ‘Good English’. But, if you want to pass this subject, kindly submit your reports in ‘Correct English’. I hope this ‘appreciation’ shows some evidence that I have profited from Prof. G’s parting advice.
Ranil Senaratna