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]

[Phys-L] Re: Looking for electricity demo apparatus

John: I've emailed Cliff for the location of the article (or you
can). His email address is: "Cliff Bettis" <>

Cliff hangs out on tap-l where the physics lecture demo group (PIRA
gang) hangs out. I will also post a few old postings from tap-l,
with apologies to those who have already read them. A lot of the
concern is over stray radiation from the old cathode ray tubes,
especially when excited by the spark coil, such as the one that
Leybold used to sell. It is supposed to be sold with a lead crystal
shield, if I recall. Karl

On 03/17/05 11:35, Karl Trappe wrote:

Check with Cliff Bettis at Nebraska. He wrote an article

Like where, man?

I got no relevant hits from

on spark
coil radiation that's enough to scare your pants off! He was the
radiation safety officer for his department, and had to ban his own
lecture demo apparatus.

Did he actually measure it? I'm surprised, unless there's
a pretty decent vacuum involved. I would have thought the
V=IR drop would greatly de-energize the electrons as they
go through the air.

I think the high frequency nature of the hand
held tesla gets around the danger.

What's the mechanism whereby frequency affects this sort
of Xray production?

Dr. Karl I. Trappe, outreach consultant Home (512) 264-1616
Research Scientist Associate V (retired)
Senior Lecturer in Physics (retired)
Physics Department, Mail Stop C-1600
The University of Texas at Austin
Austin, Texas 78712-1081
Phys-L mailing list