AC Circuits Class

In the early 80’s, I had the privilege of being in one of Professor Yu Chang’s AC circuits classes at Union College.  It was obvious that he took pride in unmasking the less-than-intuitive mysteries of the configurations of components.  I was fascinated as I learned.

Not so for all of my classmates.  Two were young employees of GE, who regarded the course as a means to an end rather than an enlightening experience.  Class after class, Professor Chang’s frustration with their attitude became more apparent.  Frustration turned to action after a particularly galling inquiry suggesting, “Why are we bothering with this?” 

Professor Chang did not answer.  Instead, he turned to the blackboard, picked up the chalk, drew a horizontal line near the top, and then shaded the space above.

“What is that?” he asked.  We all looked around uneasily, not knowing what to say.  

“That is Heaven.”

He turned back to the board.  Another line horizontal line appeared near the bottom, this time with shading underneath.

“What is that?” he asked.  The room was silent, but the sidelong glances said, “This man has lost it.”

“That is Earth.”

He turned back to the blackboard one more time and proceeded to shade the space in between the two lines.  As he shaded, he asked, “What is this?”

When no one answered, he placed the chalk in the holder beneath the illustration, turned to the class, looking directly at the perpetrators, and calmly stated, “That...is Engineering.”

Professor Chang quickly turned and left the room, abbreviating our session.  All eyes turned to the malcontents, letting them know that our instructor was not the only one displeased.  Though the two remained in the few classes left in the semester, they never said another word.