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Moving nuclei?[edit]

I think that the sentence "The positively charged nuclei will move slightly away." must be reviewed or deleted. I don't think that the nuclei move (apart of their natural vibration) due to the displacement of the electonic clouds around them. If in one atom the electronic density moves towards an external (let's say positive) charge, the (positive) nuclei should follow the (negative) electronic density, due to charge attraction, not go away. The induced dipole on one atom would induce other nearby atomic clouds to comb towards it to neutralize in some extension the positive charge that has arisen in the vecinity, while all the atomic nuclei remain in their initial relative positions. — Preceding unsigned comment added by Fepeguinux (talkcontribs) 02:44, 1 January 2012 (UTC)

The nuclei are located at equilibrium positions of minimum potential energy established by the orbitals of the valence electrons in their chemical bonds with neighboring atoms. The external electric field changes the shape of the orbitals and the bond angles in complicated ways, causing shifts in the equilibrium positions, in addition to the simple shift outward caused by the external field at the nucleus. The end result is that the "positive charge center" of each molecule or unit cell is displaced outward, away from the external charge, relative to the "negative charge center" which is displaced inward. Your proposal raises an intriguing point: do we define the "position" of a molecule by the location of the nuclei (your suggestion) in which case, under the polarizing influence of the external field, the electron orbitals move; or do we define it by the position of the chemical bond orbitals, in which case the nuclei move; or do we define it by the "charge center" of the molecule, in which case both move? Of course, this is far too technical a point for this article. I think the simple discussion in this article should describe polarization as a motion of both the nuclei and the electrons. Anything else will be too confusing for nontechnical readers. That's also the way it is described in reliable sources: 1, 2, 3 --ChetvornoTALK 21:47, 1 January 2012 (UTC)

Moving charge?[edit]

I think there can be some confusion with the sentence "The pith ball can be charged by touching it to a charged object, so that some of the charges on the surface of the charged object move to the surface of the ball." The confusion comes when talking about charging a pith ball positively, because positive charge (or protons) are not moved; rather electrons move from the pith ball to the positively charged rod. Is this something that should be addressed? K of slinky (talk) 13:50, 10 July 2012 (UTC)

John Canton[edit]

According to the Wikipedia article on John Canton, he was the son of a weaver rather than a weaver's apprentice; he was a schoolmaster by profession and an important amateur physicist (although I imagine he would have described himself as a natural philosopher). He was elected FRS (22 March 1750), and not without good cause. Moletrouser (talk) 10:05, 5 July 2014 (UTC)