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Uniform electric fields

Question: Please explain how a uniform electric field can be obtained


Uniform electric fields.
These can be produced between two parallel metal plates when a potential difference (voltage) is applied between them. The lines of the field (going from positive to negative) will be parallel to each other (hence a uniform field) and perpendicular to the plates.

There is a problem at the edges of the plates where the lines of force will curve. This can be overcome by using what is called a guard ring. If the two original plates are circular then the guard ring is simply an annular shaped plate surrounding them. This is also connected to the applied voltage.

© Keith Gibbs 2011