energy conversion [was "exploding wire"]

["Tesla list" <tesla@xxxxxxxxxx>]

Original poster: "alfred erpel" <alfred@xxxxxxxxx>


Hi Peter,


	Not to be pedantic, and although 103,000 joules is enough to kill
1000s of people if properly concentrated, it is not near the energy of a
stick of gelignite (dynamite for Americans).  103,000 joules will keep a 25
watt light bulb going for just over an hour.  The energy in a pound of TNT
will light the same light bulb for over 21 hours.  Check out
http://www.1728.com/convenrg.htm to confirm this.  Check out the root site
for all kinds of physical conversions http://www.1728.com/ .

	1 joule  =  1 watt-second  =  1 newton-meter = .73756 foot-pounds
(admittedly the site could be better since they don't talk about
newton-meters, does anyone know of a better conversion site?)

	I am going to guess that it only takes about 15 joules to kill
someone with a worst possible scenario.  Imagine lying down on a table with
a pointed blade suspended 1 foot above you at the bottom of an 11 pound
weight.  When that ll pound weight drops and the blade passes between your
ribs and punctures your heart, you are dead.  15 joules ~= 11 foot-pounds.

	As an analogy, a capacitor has the concentrating ability with
coloumbs as a knife blade point has to the momentum of the dropping mass.
The same dropping mass with a flat bottom (and no knife point) would thud
uncomfortably on your chest and cause you no harm.


Regards,

Al Erpel



> -----Original Message-----
> From: Tesla list [mailto:tesla@xxxxxxxxxx]
> Sent: Tuesday, June 13, 2006 7:28 PM
> To: tesla@xxxxxxxxxx
> Subject: Re: exploding wire
>
> Original poster: "Peter Terren" <pterren@xxxxxxxxxxxx>
>
> Wow! 103kJ is massive and incredibly dangerous. Yours really
> is up into the sticks of gelignite range of explosive equivalent.
> All my caps together are 38kJ but different voltages. My
> largest single shot was still only 5kJ and that is not good
> to be close.
> Another word of caution is that you need to watch peak
> currents.  My Maxwells are rated for 100kA (peak or fault).
> With my 3 parallel caps the rating is 300kA if the current
> was shared equally. I have gone up to 80kA and possibly
> higher.  You can't just short circuit these big caps without
> going above their ratings.
> Also ratings include voltage reversal. My Maxwells are rated
> at 80% but the Aerovox caps are physically smaller with
> higher energy but rated at 20% only which is easily exceeded
> in can crushing.
> Peter
> http://tesladownunder.com/
>
>
> >Original poster: "Paul Marshall" <klugmann@xxxxxxxxxxx>
> >
> >I have a 25kv 330uf cap bank (103,000 joules) I wonder how
> big a wire I
> >could use..
> >Paul S. Marshall
>
>
>
>
>