(adsbygoogle = window.adsbygoogle || []).push({}); 1. The problem statement, all variables and given/known data

I have found this problem in Feynman Lectures on Physics vol. 2:

Two equal conducting spheres, one with the total charge of [tex]+Q[/tex] and the other with a total charge of [tex]-Q[/tex], are placed at some distance from each other. What is the force between them?

2. Relevant equations

Coulomb's Law:

[tex]F=k\frac{q_{1}\cdot q_{2}}{r^{2}}[/tex]

3. The attempt at a solution

There is a tip to solve that problem by constructing an infinite number of images, so I tried to do it that way:

[PLAIN]http://img338.imageshack.us/img338/4906/rysp.jpg [Broken]

X-coordinate of the n-image will be:

[tex]x_{n}=\frac{R^2}{d-x_{n-1}}[/tex]

The charge we have to place in that coordinates is:

[tex]q_{n}=\frac{R}{d-x_{n-1}}\cdot q_{n-1}[/tex]

Of course: [tex]x_{0}=0[/tex] and [tex]q_{0}=Q[/tex]

Total force, which first sphere attract on the second, will be:

[tex]F_{12}=\sum{k\frac{q_{n}\cdot (-Q)}{(d-x_{n})^2}}[/tex]

Is that correct solution or not? And how to do the last operation?

**Physics Forums | Science Articles, Homework Help, Discussion**

The friendliest, high quality science and math community on the planet! Everyone who loves science is here!

# Homework Help: Two conducting, charged spheres

Can you offer guidance or do you also need help?

Draft saved
Draft deleted

**Physics Forums | Science Articles, Homework Help, Discussion**