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Re: Rolled Cap Supprise!
At 10:25 PM 1/27/97 -0700, you wrote:
>Subscriber: jim.fosse-at-bdt-dot-com Mon Jan 27 21:58:11 1997
>Date: Mon, 27 Jan 1997 05:20:19 GMT
>From: Jim Fosse <jim.fosse-at-bdt-dot-com>
>To: tesla-at-poodle.pupman-dot-com
>Subject: Rolled Cap Supprise!
>
>Home Rollers,
>
> Today I was rolling my forth rolled cap (2 layers of 0.060
>poly) when I picked it up to put it in it's case, I got a shock from
>the plates strong enough to feel like I'd hit my funny bone! I didn't
>think of an electric shock at first so when I picked it up again, I
>received a weaker shock. I am using virgin plastic so the charge is
>not from dielectric relaxation.
>
>I'm guessing that triboelectric charging caused it even though the
>relative humidity is 75%.
>
>(10 minutes later) I checked it again with a NE2. It's not charged.
>
>It was quite a supprise and interesting in retrospect. I've never
>taken a jolt from a charged 9nF cap before. It couldn't have had much
>voltage on it or I would have dropped the cap.
>
>
> Shockingly,
>
> jim
>
>
Jim,
Plastics of the high insulation types such as P.E. and Telfon triboelectrify
very easily!! I can soak a sheet of teflon in water for 6 hours. Remove it
and not dry it, but just lay it down soaking wet and let it just air dry and
4 hours latter just approach the untouched sheet with my electrometer probe
and it will pin the coulombmeter needle on the 10^-8 coulomb range at 2 feet
distance!!!! The stuff exhudes negative charges even without a forceful
triboelectrification!! Glass does this too, only you get a positive
reading! This is all part of the nature of the "electrostatic series" of
materials.
I have done a special segment on this odd and fascinating occurance on our
tape #55.
Richard Hull, TCBOR