# Gauss's Law Questions

1. Sep 29, 2010

### imzack

I was searching the forums and I found someone asking the same question a while back, but i am totally confused, I thought I was understanding this stuff up to this point.

I posted and wrote up the whole problem on yahoo answers.

If someone could break down this problem and make it easier for a very slow person to understand it would be greatly appreciated!

Thanks
Zack

Last edited by a moderator: May 4, 2017
2. Sep 29, 2010

### kuruman

Hi imzack and welcome to PF. It would be easier if you posted the problem here. Anyway, for part (a): Can you use Gauss's Law to find the electric field at a point inside the sphere?

3. Sep 29, 2010

### imzack

yea, and just got the answers, but i didnt know and didnt understand how they got to them, is someone could break it down it would be most appreciated!!

question-
An early (incorrect) model of the hydrogen atom, suggested by J.J. Thomson, proposed that a positive cloud of charge +e was uniformly distributed throughout the volume of a sphere of radius R, with the electron (an equal magnitude negatively charged particle -e) at the center.
A) using Gauss's law, show that the electron would be in equilibrium at the center and, if displaced from the center a distance r<R, would experience a restoring force of the form F=-Kr, where K is a constant.
B) Show that K=(ke)(E^2)/R^3
C)Find an expression for the frequency f of simple harmonic oscillations that an electron of mass me would undergo if displaced a small distance (<R) from the center and released.
D) Calculated a numerical value for R that would result in a frequency of 2.47*10^15 Hz, the frequency of the light radiated in the most intense in the hydrogen spectrum.