Re: microwave ovens Re: Ball lightning - Terry's thoughts....

["Tesla list" <tesla@xxxxxxxxxx>]

Original poster: Just Justin <rocketfuel@xxxxxxxxxxxxx>



On Tue, Aug 16, 2005 at 12:24:33PM -0600, Tesla list wrote:
> Original poster: boris petkovic <petkovic7@xxxxxxxxx>
>
>
>
> --- Tesla list <tesla@xxxxxxxxxx> wrote:
>
>  > Original poster: Jim Lux <jimlux@xxxxxxxxxxxxx>
>  >
>  > At 10:18 PM 8/11/2005, Tesla list wrote:
>  > >Original poster: Scott Stephens
>  > <scottxs@xxxxxxxxxxx>
>  > >
>  > >Tesla list wrote:
>  > >
>  > >>some physics student claimed that microwave ovens
>  > couldn't produce corona,
>  > >>since 500 watts RF doesn't give a wave with a high
>  > enough voltage to
>  > >>trigger sparks.
>  >
>  > To get corona, all you need is a local field >
>  > 30kV/cm, which is
>  > pretty easy to achieve with conductive stuff in the
>  > cavity.  Crumple
>  > some aluminum foil and throw it in the microwave,
>  > and you'll see
>  > plenty of little sparks where the local field
>  > exceeds the limit.
> -----
> Hmm..I've put once a very thin wire to ~6000 V terminal
> end of a  transformer (frequency 50 Hz).
> Expected to see a tiny corona discharge from ends of
> the wire becouse of E>>30 kV/cm.
> To my surprise,no corona I could notice per see.
> Even in a complete dark I was unable to detect any of
> it..I thought the transformer was dead or
> something,but it wasn't.
> Maybe the corona is also a voltage thing when it comes
> to lower potentials and industrial frequencies?I would
> say some form of  discharges exist in such cases but
> humans can't detect them by their senses.
> What do you think ?
>

Hi Boris,

I believe that your 6000V is 6000V relative to ground or possibly
the negative terminal of your transformer.  So you should be measuring
the distance between your wire end and the other terminal to use
in the 30kv/cm formula.  If you move your test wire closer to ground
you may see the corona, or maybe a spark if you get too close ;)

Justin