Re: Capacitor and Force

On Oct 13, 3:15 pm, "Jon Slaughter" <Jon_Slaugh...@xxxxxxxxxxx> wrote:
"Tom Bruhns" <k7...@xxxxxxx> wrote in message
....


As Phantom says, the SAME is true for gravitational attraction; two
massive plates separated by x where x is small compared with the
extent of the plates will not be attracted with the same force as two
point masses separated by x.

Hmm, so what your saying is that the force of gravity due to the earth,
i.e., m*g, is wrong?

You seem to have a bit of a comprehension problem. That is not at all
what I wrote. For exactly the same reason that charge uniformly
distributed on a spherical shell can be considered a concentrated
point charge at the center of the sphere with respect to its
interaction with charges external to the shell, gravitational
attraction from mass uniformly distributed on a spherical shell may be
considered as a point mass at the center of the sphere with respect to
its action on masses outside the shell. THAT I have worked through
with an integral a time or two; it's actually quite straightforward.
Try it; you'll like it. But that does NOT work for arbitrarily
distributed mass, or arbitrarily distributed charge.

....

Again though, if you think computing two nested volume integrals is fun then
by all means go ahead and do it. I'll be waiting for your result.

I do integrals for myself when I want to, whether for entertainment or
learning or whatever. I do integrals for my employer as necessary;
I'm paid for that. Now I should do an integral for YOU because???
"I'll be waiting for your signed contract and credit references."

By the way, you DO realize that there's no need to do a volume
integral, don't you?


.

Relevant Pages

  • Re: Acceleration of charge
    ... The point seems to be that the energy of a ... but a single lone charge is of course a massive ... otherwise your volume integrals aren't well defined and that's ... I think "dV" is a scalar, ...
    (sci.physics.relativity)
  • Electrical circuits and charge - caution, lengthy
    ... convergence of improper integrals). ... calculus step in several derivations that I can not follow 100%. ... which makes sense and the charge must be decaying. ...
    (sci.physics)
  • Re: Gauss Law and spheres
    ... You have a hollow sphere with no charge enclosing a charged solid ... Gauss' law in integral form is a _surface_ integral - path integrals ...
    (sci.physics)
Loading