- #1

Philip Koeck

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- TL;DR Summary
- Do neutral solids have a negative surface charge and does this distribute itself in a way so that the electrostatic field outside is zero everywhere no matter what shape the solid is?

Also referring to the post by @Kostik plus answers, I'm wondering about surface charges of neutral solids such as metals or carbon, for example.

I only want to discuss large scale effects so that the solid can be treated as continuous. The atomic structure is averaged out.

I also assume that this solid is not influenced by anything else. Let's say it's alone in empty space far from any other object.

It seems that every solid has to have a negative charge layer at the surface and the corresponding excess of positive charge below the surface.

At least this is the only way I can make sense of the mean inner potential (always positive) of a solid.

Assuming this is correct the field

So would the field outside an infinitely large, plane surface.

But what about a more general solid object, for example a cylinder or a cone (or a potato-shaped object)?

Would the charges distribute themselves in such a way that the field is zero

I only want to discuss large scale effects so that the solid can be treated as continuous. The atomic structure is averaged out.

I also assume that this solid is not influenced by anything else. Let's say it's alone in empty space far from any other object.

It seems that every solid has to have a negative charge layer at the surface and the corresponding excess of positive charge below the surface.

At least this is the only way I can make sense of the mean inner potential (always positive) of a solid.

Assuming this is correct the field

**outside a sphere**would still be zero due to Gauss' law and symmetry.So would the field outside an infinitely large, plane surface.

But what about a more general solid object, for example a cylinder or a cone (or a potato-shaped object)?

Would the charges distribute themselves in such a way that the field is zero

**everywhere**outside the object or would only the flux through a surface surrounding this object be zero?
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