# Charge inside a spherical shell

SammyS
Staff Emeritus
Homework Helper
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Hello ehild

"Every charge in space exerts a force on the charge inside the shell.
The central charge is being acted on by all charges in space, including the charge induced on the inner and outer part of the shell and the charge outside the shell."

Is this correct ?
Yes, this is true , but --- (That's the dreaded "Oh! Oh! here it comes now", but) ---

Consider the electric field due only to the external charge and the charge on the outer surface of the sphere:
The external charge induces the charges on the exterior of the conductor (in this case, the sphere) to distribute themselves in such a way that the electric field inside the surface of the conductor is zero.

The net effect of this is that no matter where you place charges external to the conductor the field produced (by these charges plus the surface charge) at any location within the outer surface of the conductor can be ignored, because that field is zero. Of course, this assumes the external charges are stationary.​

Any field inside the inner surface of the conductor is due to the charges on the inner surface and any charges within the conductor.

haruspex...SammyS...ehild...thank you very much