I posted this message a few minutes ago. Jim ---------- Forwarded Message ---------- Subject: Physics 106, Spring, 2001 homework Date: Mon, 16 Jul 2001 18:55:53 -0400 From: James R. Frysinger <[EMAIL PROTECTED]> ... Dear Professors Groth and Nice, I was scanning some web pages on the internet this morning on the topic of capacitors when I came across your homework solutions page at http://phy106.princeton.edu/hwk_s01/hw03sol.pdf Out of curiosity I have pointed some of my colleagues to this page, so they might ask you about this separately. Immediately I was struck by the surprising realization that you are using electrostatic units for at least some of your teaching and homework assignments. This has stimulated my curiosity and some questions come to mind. I haven't seen these units in print since I read the journal articles written by Millikan a century ago regarding his famous oil drop experiments. In fact, the use of esu's was superceded so long ago that I cannot find the date on which they were deprecated. Certainly, they were replaced when the SI was brought into being forty years ago. I am on two IEEE standards committees (one jointly with the ASTM) and I cannot recall ever seing those units used in any of their materials. Nor can I recall their use in any AIP publications in the last few decades. I would appreciate it if you would take a few minutes to satisfy my aroused curiosity. Could you tell me why you still use them and also what textbook support you have for your students on esu's? To that point, what is the textbook assigned for this course? If you use esu's I must assume that you might be using emu's as well. Would that be correct? What do you tell your students about the use of esu's and emu's in modern journal articles? Reading down several lines I see your comment that "the unit pF is pronounced 'puff'". Is this an inside joke that you have with your students or did you intend for that to be a valid comment? If the latter is true, do you also encourage the use of "kilo" for kilogram and "klick" for kilometer in your teaching of mechanics? Taking the risk of offering unsolicited advice, I recommend that the use of nicknames for SI units by the students (or anyone else) neither be encouraged nor tolerated. regards, James R. Frysinger -- James R. Frysinger University/College of Charleston 10 Captiva Row Dept. of Physics and Astronomy Charleston, SC 29407 66 George Street 843.225.0805 Charleston, SC 29424 http://www.cofc.edu/~frysingj [EMAIL PROTECTED] Cert. Adv. Metrication Specialist 843.953.7644 ------------------------------------------------------- -- James R. Frysinger University/College of Charleston 10 Captiva Row Dept. of Physics and Astronomy Charleston, SC 29407 66 George Street 843.225.0805 Charleston, SC 29424 http://www.cofc.edu/~frysingj [EMAIL PROTECTED] Cert. Adv. Metrication Specialist 843.953.7644
