My high school chemistry teacher (and one of my favorite teachers of all time) from the previous year taught my senior year physics class. When she had submitted her order for chemistry and physics supplies over the summer, the principal decided he needed to cut back and (without consulting her) took the first page of her request and discarded everything else. Well, the first page happened to just include chemicals for her chemistry class. Thus, nothing for her physics class was ordered. She was not happy, but she did the best she could with what she had. (It must have been okay since I had no trouble in my freshman physics at Carolina.)
I was one of a group (today we’d probably have called geeks) that hung out in her classroom during lunch. One day she was going through the supply closet trying to find something to use to teach physics with and found an old Van de Graaff Generator. When she told me what it was, I was hooked! Therefore, my assignment for the grading period was to make it work for an A.
Well, I went to the 1974 edition of Google (World Book encyclopedia) for information. The belt and the ground source were missing but the motor worked, the acrylic tube was cracked but intact, and the ~12” aluminum top sphere was undamaged. My mom took an old silk dress and sewed a new belt. I went to the local hardware store and bought some ¼” mesh hardware cloth for the ground source. I redrilled the acrylic tube and put everything together. Within a week, I had it working.
It would throw a “bolt” of ~150,00 VDC static electricity (per label specifications) around 6 inches. The bolts of static electricity tingled/burnt a little when they hit my arm and even left a little light burn mark, but it was way too cool to worry about! I demonstrated it to the class, taking the brunt of the electricity through my fingers and lighting the ceiling fluorescent lights by holding one 4’ fluorescent tube in the other hand while touching the ceiling light bulb. Way cool!
My physics teacher decided it worked so well, that I should demonstrate it to all of the science teachers in my high school. She arranged a time for a demo. Since the sparks were relatively small and dim, she arranged for the demo to be held in a very small storage closet with no windows. All of the science teachers and the assistant principal attended. I had everything set up, so when the time came, I flipped off the lights and hit the switch for the Van de Graaff…
Okay – Just a very brief weather forecast for that autumn day: It was the first really cold day of the season and the humidity was very, very low … Now back to the story.
As I continued to explain the principle of the Van de Graff, a bolt of static electricity hit me from approximately 2 feet away. I went speechless as I lost my train of thought. Every time I moved, it struck another uninsulated part of my body (i.e., hands, arms, face). Yes, the light(ening) from the spark was bright, but I could not find the light switch. As the science teachers started to stand up, the static electricity reached out into the small enclosed space and struck them. In hast (panic), I scrapped the wall for the light switch until I hit it. The lights came on and I turned the Van de Graaff off. At that point, I calmly asked if there were any questions… as teachers and assistant principals exited the door.
There were none. And yes, I got an A for the grading period and was allowed to graduate from high school (even after the Saturday morning when the principal found my long lost 4 ft corn snake coiled in the center of his desk – but that’s another story…)!
L.F. Eason – OLLI Member