Chronology Current Month Current Thread Current Date
[Year List] [Month List (current year)] [Date Index] [Thread Index] [Thread Prev] [Thread Next] [Date Prev] [Date Next]

Re: [Phys-l] Zener terminology

Usually by the time students get to Zeners, they have so
much experience with ordinary diodes that the potential
for confusion is negligible.

I suppose that depends on the course and the students. We don't have electrical engineering here, but I do teach a one-semester linear electronics course for chemistry and physics majors. The focus is on understanding basic instrumentation. We go through regular diodes, zener diodes, and transistors in just a couple days. We have to cover simple power supplies, operational amplifiers, input/output transducers in one semester. In lab the students build and test some power supplies, play with op-amps, and build some simple instruments (like a pH meter). Some get diodes and zener diodes confused pretty thoroughly. Generally they want to stick a zener in a circuit with forward bias.

Maybe it's not that important for these students to get it all straight because this is essentially a "survey course" for them. Most of them are not going to build or repair their own instruments. The course is just trying to take away some of the black-box mystery of the instruments they use. But this is one data point where students indeed have some difficulty with the notion of using some diodes forward biased and other diodes reverse biased.

From the Car Talk book, I often quote the passage from the beginning of
the chapter on automotive electrical circuits. Tom and Ray say that space is not the final frontier (as said in the opening of Star Trek episodes), they say electricity is the final frontier because people don't know diddly about it. That is sure true of the ordinary science student. Nine-plus out of ten students I work with have essentially zero knowledge and experience with electricity and electronics even though they use them every day all the time.

Michael D. Edmiston, Ph.D.
Professor of Physics and Chemistry
Bluffton University
Bluffton, OH 45817