Swing when you’re lecturing

Lecturer dr. Richard Engeln swung through the cafeteria in the Auditorium last Tuesday afternoon to illustrate his lecture on periodic motion. It was his third demonstration in light of his lecture series on Applied Sciences for the Bachelor College. His lecture was attended by seven hundred students.

Students were expecting a demonstration comparable to those of Walter Lewin, so the oscillation of the pendulum came as a slight disappointment for many students. Nevertheless, Richard Engeln deliberately opted for a minor oscillation. “The formula is an approximation that only works at small angles, and that’s what students were supposed to gather from this demonstration,” says the lecturer.

During the demonstration, Engeln (lecturer at the Department of Applied Physics) showed the period does not depend on the mass or the oscillation of the pendulum. The latter could be shown easily. He dropped a ten-pound ball from a five and ten-degree angle. In order for the measurement to be accurate, he measured ten periods.

To show the mass is irrelevant to the oscillation as well, he said he was to swing himself, an announcement for which he was treated to a cheering crowd.  After having detached the ball and fastening himself to the construction, he swung back and forth ten times himself. He weighs approximately fourteen times as much as the ball – a significant difference. At both angles, the ball had a period of 5.08 seconds. Richard Engeln’s swing  lasted just as long, accurate to a hundredth of a second.

After the demonstration, students were divided into three lecture theaters where the theory of the subject was discussed elaborately. Demonstrations for these classes have been initiated by Richard Engeln. He and five other lecturers of several departments are responsible for the theoretical part of the course. There will be another demonstration on Wednesday, which will be attended by three hundred English-speaking students.

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