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

["Tesla list" <tesla@xxxxxxxxxx>]

Original poster: "Denicolai, Marco" <Marco.Denicolai@xxxxxxxxxxx>

Hi Boris,

The visual corona inception field is given by the Peek's Law. For
parallel wires is:

Ev = 30 * (1 + 0.301/sqrt(r))

r = wire radius (cm)
Ev = field strength (in kV/cm)

By inspecting this equation (dated 1929 and well accepted) you'll notice
that:
1. Inception gradient increases from the asymptotic 30 kV/cm up, for
instance, to 94 kV/cm for a wire 0.02 mm in radius.
2. The wire distance is NOT relevant for Ev value.

Best Regards

> -----Original Message-----
> From: Tesla list [mailto:tesla@xxxxxxxxxx]
> Sent: 16. elokuuta 2005 21:25
> To: tesla@xxxxxxxxxx
> Subject: Re: microwave ovens Re: Ball lightning - Terry's thoughts....
>
> 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 ?
>
> Regards,
> Boris
>
>