3 ms·
> Picture yourself inside a gigantic, electrified sphere – akin to a Van De Graff generator. If your charge polarity matches that of the sphere, you'll experien
by kragen 2y ago
> Picture yourself inside a gigantic, electrified sphere – akin to a Van De Graff generator. If your charge polarity matches that of the sphere, you'll experience a repulsive force.
This is not correct. The field inside a charged conductor is zero. You will experience no force. If there is a hole in the sphere you will experience a repulsive force if you are close to the hole (compared to its size).
- Arnavion 2y agoYes, just like with Newtonian gravity. Any inverse-square law force will be zero inside a spherical shell. The higher force from parts of the shell closer to you is exactly canceled out by the farther parts exerting less force but there being more of those farther parts. https://en.m.wikipedia.org/wiki/Shell_theorem https://en.m.wikipedia.org/wiki/Shell_theorem
- kragen 2y agoFor gravity, it's only true for spherical shells, but in the case of charged electrical conductors, it's true no matter what the shape of the shell is. The field inside a charged, conductive small stellated dodecahedron is also zero everywhere inside. That's because the charge in the conductor migrates as long as there's an electrical field to make it migrate; it stops moving once it neutralizes the field. (If you made an actual small stellated dodecahedron with infinitely sharp points, the charge would leak away from the points via field emission. Or, in theory, you'd have an infinitely strong electrical field there, and therefore all kinds of singularities. But reasonable approximations of the setup are possible in real life.)