# Protons and electric fields

Discussion in 'General Electronics Chat' started by mlkcampion, Sep 24, 2007.

1. ### mlkcampion Thread Starter Active Member

Nov 16, 2006
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Just a quick question regarding this comment, are protons not bound to the atom structure i.e. they can't move around like electrons? I've heard of proton shuttling not sure if it applies here, and iam aware of holes in semiconductors.

Another question regarding electric fields, when this stuff is being described in a book there is dicussion about a charge and its electric field potential dropping of at 1/r, does one assume that they are always taking about a single electron charge or a group of charges or ions? Also the units for electric field potential is V/cm^2 and i find it confusing that something that is powered from say 6v can have electric field up to kV/cm^2 is this correct?

I was just passing through the forum so if the detail seems a bit sketchy i will try to provide an example later, or move my question into another topic.

Cheers

2. ### recca02 Senior Member

Apr 2, 2007
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here proton might be intended to be used for positive ions,
if the ions are H+ then they are protons.the ions in a battery jump from electrode to solution or vice versa IIRC.

3. ### cumesoftware Senior Member

Apr 27, 2007
1,330
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Hydrogen protons present on the electrolyte are in fact the only free protons in nature. As you know, an hydrogen atom is constitued by one proton and one electron. Then a hydrogen cation (H+) is only a proton. Holes in semiconductors are a different fenomenom. They are caused by an incomplete valence shell, or in other words, a deficiency of one electron in the valence shell of the atom.

4. ### Dave Retired Moderator

Nov 17, 2003
6,960
145
'Holes' are the absence of an electron it is conceptual where the real current flow is still electrons, this is fundamentally different from a proton.

The basis for the 1/r^2 field drop stems from Coulombs Law which is derived in terms of point charges. When Gauss's Law is introduced you still see the 1/r^2 variable for many Gaussian surfaces, however Gauss's Law no longer deals with just point charges but charged surfaces. Some examples have different 1/r variables, however they all can be derived (sometimes easily, sometimes not) from first principles with Coulombs Law. A point to note is that this is often application specific.

Finally, your understanding of electric field strength appears correct, however I cannot comment on the specific application in which you have seen the numbers 6V and kV/cm^2.

Dave

5. ### mlkcampion Thread Starter Active Member

Nov 16, 2006
59
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thanks
thats right forgot bout hydrogen i guess they can only be talking about ions especially in the case of lithium ion batteries.

Any ideas on the electric field?

6. ### cumesoftware Senior Member

Apr 27, 2007
1,330
11
Indeed. In lithium ion bateries the charge carrier is the Li+ ion, instead of the usual hydrogen proton.

7. ### Dave Retired Moderator

Nov 17, 2003
6,960
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Can you re-clarify your question on the electric-field?

Dave

8. ### mlkcampion Thread Starter Active Member

Nov 16, 2006
59
0
Hey Dave
Yea i will, i just need to take a look at the book i was reading and i will find an example.

cheers

9. ### Dave Retired Moderator

Nov 17, 2003
6,960
145
Ok, which book is it?

Dave