### Author Topic: electric field screening  (Read 15838 times)

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• let the voltage do the work ##### Re: electric field screening
« Reply #24 on: July 09, 2013, 00:40:07 am »
At least from what the equations describes which is equivelant to the lorentz force law but for open circuits it has this special case where what I said above happens. In vacuum  the speed limit is v= ((sqrt2)/2)*c 70% the speed of light but when there is a medium this limit is lowered say for plasma or a capacitor which is equivelant to an open circuit. Anything inside a circuit that has different dielectric strength exhibits this because the relative velocities are different for the two parts but the current has to be interrupted for this to happen

the mean free path is very short inside liquid water

in vacuum the required voltage is above 130kV to accelerate them fast enough

F=Eq    ma=Eq    a=Eq/m   or   V=-E*dx     V=-dE/dx

so the electric field needed in vacuum is E=V / x

easy way would be using conservation of energy  Ei=Ki+Ui=Ef=Kf+Uf   V*q=1/2m*v^2

v=sqrt(2Vq/m)    v=sqrt(2Ex/m)

with the required velocity v'=sqrt2/2*c

V=m*v'^2/2q    V=m*(1/2)*c^2/(2q)

Mass of an electron is:
9.11x10^-31 kg

Charge of an electron is:
-1.60x10^-19 C (Coulomb's)

V=m*(1/2)*c^2/2q        V=9.11x10^-31 * 0.5 * (2.99 x 10^8)^2 / 2*1.60x10^-19=127256V

for argon gass I calculated 113.8kV needed but I'm not sure about the distance between atoms I used a simplistic model in reality this limit should be really lower than 130kV

I used 4.79*10^-8 as distance between argon atoms but this number should be lower when there are charges moving

the formula I derived is pretty simple see attachments
« Last Edit: July 20, 2013, 19:42:01 pm by geon »

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« Reply #25 on: July 10, 2013, 10:07:12 am »
maybe in vapor phase the water gets more mean free path... I think that is indeed possible to apply up to 100kv/mm in water according to today advance in materials science.

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• let the voltage do the work ##### Re: electric field screening
« Reply #26 on: July 13, 2013, 09:27:22 am »
from CRC handbook of chemistry: 2 H2O + 2 e ⇌ H2 + 2 OH–     reduction potential: –0.8277   @ATP @25C

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« Reply #27 on: July 13, 2013, 15:26:58 pm »
What is this reduction potential?

Could you tell me in which section you found this?

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• let the voltage do the work ##### Re: electric field screening
« Reply #28 on: July 14, 2013, 09:09:23 am »
Sorry I dont know more about it I hope someone would know lol I'm still learning  use wikipedia  http://en.wikipedia.org/wiki/Reduction_potential I found it in kinetics and electrochemistry

more useful info
energy content of hydrogen gas(heat of combustion) is 141.8 x 10^3 J/g
141.8 x 10^3 J/g    * 2g/1mol
286 kJ/mol
or 286 x 10^3 J/mol * 1mol/ 6.022 x 10^23 atoms =
4.7492 x 10^-19  Joules per atom

dissociation energy of H2 is 435.7 x 10^3 J/mol  and of cation K+H2 is 6.1 x 10^3 J/mol  and of K+H2O is 74.9  x 10^3 J/mol  , H2O vibrational data is symmetrical stretching 3657/cm, bend 1595/cm ,antisymmetrical stretching  3756/cm
« Last Edit: July 15, 2013, 14:13:52 pm by geon »

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« Reply #29 on: July 14, 2013, 12:56:50 pm »
and here is it where you are going wrong, from my point of view.
What isotope of hydrogen are you talking about?
H1? H2?, para, ortho?

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• let the voltage do the work ##### Re: electric field screening
« Reply #30 on: July 14, 2013, 14:24:15 pm »
I said H2 I havent found any info for the isotopes if you find them post them here so we can keep all these together.

« Last Edit: July 14, 2013, 16:36:16 pm by geon »

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• let the voltage do the work ##### Re: electric field screening
« Reply #31 on: July 14, 2013, 16:36:47 pm »
Inside a liter of water there are 112 grams of H or 7.9 x 10^6 Joules of H2 I can't find dissociation energy for H2O but I'm sure its greater than that..