Re: [Phys-l] Prising electrons from the atom

["sridhar chitta" <sridhar10chitta@gmail.com>]

I will keep it simple;

Q1
Instead of
"The nuclear forces between these two types of objects is so strong that no
earthly conditions can cause the electrons to merge with the nucleus, even
though they are opposite in charge".

It will read
*
"The tangential velocity keeps the negatively charged electrons in stable
orbits around the positively charged nucleus such that no moderate forces
will make the electrons merge with the nucleus in common elements, even
though they are opposite in charge".
*
Q2

I have included (outermost) to the original question

*Why cannot a hammer and chisel that can exert a force of say, 100 Newtons
be used to prise an electron away from the nucleus of a copper atom in a
copper bar given that the radius of an atom is of the order of
10**-10meters and the electric force of attraction between a proton
and an
(outermost) electron that are this far apart is a mere 2.3 x 10**-8 Newtons
?*

Although a very sharp tool is able to cut common materials, examining its
point under a microscope will show that its diameter is many atoms thick
resulting in a very small stress or force/area, less than the 2.3 x
10-8Newtons minimum required). Thus, it will not be effective in
breaking away
electrons from an atom.

The force that holds *inner *electrons to the nucleus is far greater than
the force of 2.3 z 10-8 Newtons and these cannot be affected at all by the
forces exerted by the hammer and chisel.

* *

*On the other hand, molecular forces like adhesion, which is used in static
electricity will easily pry away charged fragments from a material* e.g
polymers or plastic combs.





On Thu, Dec 18, 2008 at 7:18 PM, John Denker <jsd@av8n.com> wrote:

> On 12/18/2008 03:39 AM, Joseph Bellina wrote:
> > Triboelectricity is a tricky topic.  As John says, rubbing one metal
> > against another doesn't do it.
>
> I didn't say that.
>
> >  It will serve to remove the surface
> > films so that the metals are indeed in direct contact, and then
> > electron transfer can occur depending on the work functions.
> >
> > Triboelecticity seems to occur most often when one of the materials
> > is a polymer.  Sherwood and Chabay do a nice job of showing that the
> > energies involved are not sufficient to transfer electrons, but could
> > transfer charged polymer fragments.
>
> That's narrowly true if we emphasize the "seems to" ... but
> there's no physics in that.  It only "seems to" be so on the
> basis of casual at-home experience.  If you look a little
> deeper you discover that some of the biggest static-control
> problems occur at industrial plants that handle powdered
> metals.
>
> Rubbing one metal against another *will* do it.  Big time.
>
> Ben Franklin divided all materials into two categories:
> "electrical materials" such as silk and glass, versus
> "non-electrical materials" such as metals.  In other
> words, he got it completely wrong.
>
> If you're serious about electricity, static or otherwise,
> you use metals for the electricity, and use polymers, air,
> and/or vacuum to make insulating handles and spacers.
>
> > So I don't think triboelectricity is the way to think about this.
> > Isn't the problem a matter of how to affectively couple to the
> > electrons...a hammer just doesn't do it.
>
> Using a "sand blaster" apparatus to blow powdered metal
> against the face of your hammer will do it just fine.
>
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Sridhar Chitta