Quantitative electric field measurements in an intermediate laboratory

Abstract

We describe an apparatus that enables students to study the electric fields and the associated surface charges for several different electrode structures including parallel plates, cylindrical rods over plates, and nested cylinders. The study involves the relations among potential difference, electric field, surface charge density, and total charge. These relations are confirmed to within a few percent.

Quantitative analysis of the electric dipole on finite sized graphite sheets

“…for a single positive charge, 3 where r ref is an arbitrarily chosen reference distance. The total potential ⌽ at the point ͑x , y͒ from all of the images is equal to the following ͑slowly͒ convergent sum:…”

“…2͑b͒. 3 A positive voltage of +4 V is applied at a 0.5 cm radius silvered section 4.0 cm up the y-axis, and a negative voltage of Ϫ4.0 V is applied at a 0.5 cm circle down the y-axis from the origin.…”

The potential of a uniformly charged planar structure with shape of a rose curve

“…This involves the relationship between equipotential lines and the shape of the charged body, thereby confirming the interdependence of field sources [1,11,12]. However, due to the constraints of the electrode shapes in this classic experiment [11,19] and the entrenched mindset of traditional teaching, they did not delve deeply into the distribution of potentials on the defined paths in the electrolytic tank, i.e. the relationship between the potential curves and the shapes of charged objects.…”