Repulsive force by itself on a charged sphere

AI Thread Summary
A charged sphere can hold a significant amount of charge, but the repulsive forces can cause it to blow apart if not properly contained. Wrapping the sphere in an insulator and using a semiconductor for charging may help, but the mechanical stresses on the charged surface need to be calculated to ensure stability. The discussion references historical investigations into the properties of charged spheres, particularly around 1900, which explored the mechanical stresses involved. Understanding these stresses is crucial for determining how to maintain the integrity of the charged configuration. The topic highlights the balance between charge containment and the forces at play in charged systems.
Zeor137
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I was wondering how could I hold a lot of charge inside, for example, a ball. I thought by wrapping it in an isolant and using a hole with a semiconductor to charge it without letting anything out. But them it also could blow apart by the repulsive force of itself. Therefore, I got curious of how to calculate the pressure necessary to hold it still. I thought about considering it a bunch of infinitesimal balls with infinitesimal charge but I don't now enough calculus yet to put it in a equation.
 
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For any conducting sphere all of the extra charge will move to the surface; any other configuration is unstable.

The math is given here: http://hyperphysics.phy-astr.gsu.edu/hbase/electric/elesph.html#c2

Your question then becomes: what are the mechanical stresses on the charged spherical shell with surface charge? This was investigated extensively around 1900 while trying to understand the properties of the newly discovered electron. For example, Poincare stress:
http://en.wikipedia.org/wiki/Electromagnetic_mass#4.2F3_problem
 
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