Re: short question (about Faraday Cage)

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Original poster: "Jim Lux by way of Terry Fritz <teslalist-at-qwest-dot-net>" <jimlux-at-earthlink-dot-net>


----- Original Message -----
From: "Tesla list" <tesla-at-pupman-dot-com>
To: <tesla-at-pupman-dot-com>
Sent: Thursday, March 06, 2003 7:13 PM
Subject: RE: short question (about Faraday Cage)


 > Original poster: "John H. Alderman III by way of Terry Fritz
<teslalist-at-qwest-dot-net>" <alderhood-at-bellsouth-dot-net>
 >
 > Given that the energy is dissipated in the walls or the lights how about
 > thumb rules or experience rules or engineering/math for calculation and
 > design? Is this a build it and see what happens?

You got it... build it and try.  Figure generally this way... worst case is
that the tesla coil is 100% efficient from wall plug power in to spark power
out. worst case is that the sparks dissipate no energy. All the power from
the wall plug winds up in the cage.  You could probably figure that it's
unevenly distributed, but probably no worse than 10:1 uneven.  So you can
get a "watts/square foot" number, which is going to be pretty low. (lots of
square feet...) Since there is lots of air surface contact area, those watts
get dissipated easily.


  Is the energy input to the
 > coil with associated physical parameters lead one to know power available
 > for lights and dissipation in resistivity and induction in the walls?

Yep.. but, the tricky thing is knowing how much energy is dissipated in the
sparks.  You can do a "circuit model" and replace the sparks from the top
load with a 220K resistor and a capacitor, making the waveforms look about
right, but whether the power dissipation in the spark is equivalent to that
in the 220K resistor is another question.

  Does
 > the energy absorbed by a florescent 40 watter tube mainly exist for
filament
 > heating?

No.. the filament shouldn't be drawing much powe except during start.  It's
actually going into exciting the mercury vapor (and heating the glass
tube.... feel a lamp that's been on a while, and the temperature is fairly
even over the length).  However, a TC lighting up a fluorescent lamp doesn't
light it up anywhere near as bright as the normal operation.

  How much in the actual excitation to produce the UV that excites
 > the powder? Is the UV from the valence electrons of the Ar?

Mercury vapor in most fluorescent tubes...

  Will yall (yes
 > he's in Georgia) direct me toward heavy FAQs and online sources and direct
 > to me by email to rapid boot my knowledge up? I guess I'm going to be
 > dedicating a shipping container to this experiment !
 >
 > Seems I have been here before at least once...
 >
 > John Alderman
 > alderhood-at-bellsouth-dot-net
 >
 > -----Original Message-----
 > From: Tesla list [mailto:tesla-at-pupman-dot-com]
 > Sent: Thursday, March 06, 2003 9:22 AM
 > To: tesla-at-pupman-dot-com
 > Subject: Re: short question (about Faraday Cage)
 >
 >
 > Original poster: "davep by way of Terry Fritz <teslalist-at-qwest-dot-net>"
 > <davep-at-quik-dot-com>
 >
 >
 >  >I am knew so some patience please:
 >  >What happens when you put a tesla coil in a Faraday Cage?
 >
 >           If the cage is big enough, it runs normally. WHAT IS BIG
 > ENOUGH???????????????????????????????????????????
 >
 >  >Where does the energy go?
 >
 >           Lost in resistive losses in the cage walls. Calculation or
 > observation?????????????????????????
 >
 >  >What happens to flourescent lights in the cage?
 >
 >           Depending on exact position, they may light.    What defines
 > depends???????????????????????????????????
 >           (in which case THAT energy does not get to the
 >           cage walls...)
 >
 >           best
 >           dwp
 >
 > ...the net of a million lies...
 >           Vernor Vinge
 > There are Many Web Sites which Say Many Things
 >           -me
 >
 >