Voltage inside a conductor?

[kfcman289]

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Can someone explain to me why the voltage inside a conducting sphere would be the same as the surface? Wouldn't voltage change with distance inside the sphere?

 

[Cawolf]

A conducting sphere will have all free electrons at the surface - with a E field inside of zero.

The potential will be constant inside due to no field - the potential is the rate of change of the field, so no change in field results in a constant potential.

Therefore at any point inside a conducting sphere V=kQ/r

 

[kfcman289]

A conducting sphere will have all free electrons at the surface - with a E field inside of zero.

The potential will be constant inside due to no field - the potential is the rate of change of the field, so no change in field results in a constant potential.

Therefore at any point inside a conducting sphere V=kQ/r

So to clarify, any electric field between to points only exists if there is a voltage difference between them?

 

[Cawolf]

Hm. I am not sure what you are asking exactly. The electric field is a way of describing the force that a charged particle would feel at that point in space through the relationship Force = (E Field)(Charge).

Voltage is a way of describing the potential energy per charge as V=U/Q.

They are related though as the Electric field can be described as the negative gradient of the potential. An electric field is defined differently at each point in space however based on it's distance from the charge creating the field.

If you were to look at a point on a line between two opposite charges, there may be a point between them where the potential is zero when the potentials "cancel". This point will have possibly have a non-zero electric field though.