Field strength
Field strength is a quantitative expression of the intensity of an electric field at a particular location. It is expressed as the vector H and is measured in units of amperes per metre.
The standard unit is the volt per meter (V/m or V·m-1). A field strength of 1 V/m represents a potential difference of 1 V between points separated by 1 meter. Electric field strength is also referred to as electric field intensity.
To measure the field strength, a test charge positioned at one of the vector points within the electric field of the source object is needed. This test charge should have a small positive charge that does not interfere with the source charge. The test charge makes it possible to measure the electric field strength of the source charge at the vector point where the charge is positioned.
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