Re: Induced dipole moments

[Ludwik Kowalski <KowalskiL@MAIL.MONTCLAIR.EDU>]

Ludwik Kowalski wrote:

> 4) Suppose we have two "rigid clouds". A rigid cloud,
> by definition, is a set of identical point charges which
> can not move with respect of each other. Yes, it is a
> highly unrealistic model; I do not care what keeps
> particles at fixed positions with respect to each other.
> Two such clouds can penetrate through each other
> because distances between particles (inside of each
> cloud) are large.
>
> 5) One cloud is made of electrons and another is
> made of protons. Let d be a distance between the two
> centers of charge. The attractive force between the clouds
> is proportional to 1/d^2 when clouds are separated. What
> is wrong by assuming that this relation holds even when
> the two clouds are overlapping?

In suppose David will say that + charges in "overlapping
regions" cancel -q charges  and the "net charge" of each
cloud (to be used in the Coulomb law to calculate the attractive
force between the clouds) also depends of the distance d.
Small values of d result in small net charges and the restoring
force increases when d becomes larger (but not too large).

Perhaps this is a correct explanation of induced polarization.
But it brings another question. What do we mean by "canceling
charges" in the overlapping region? Particles in the overlapping
region remain charges as before. Therefore they do interact
with each other. Overlapping regions also repel each other.
Ludwik Kowalski