# Electrostatic interaction

hello!

which equation descripts the electrostatic interaction between two non-point (ie. that have dimensions) charged particles?

thanks!

## Answers and Replies

Delphi51
Homework Helper
That would be different for every shape! Start with the formula for point charges and integrate over all the infinitesimal charges in the shape. Spheres work out nicely; other shapes do not.

Yeah, i want for spheres only, forgot to mention

Delphi51
Homework Helper
For spheres, just use the point charge formulas - as if the entire charge was located at the center point. Make a note that you need to work that out for yourself once you take 3D calculus.