Experiment Work: Characterization of a 2D Electrostatic Field

Topics covered:

- Electrostatic field

- Electric field (V/m)

- Planar capacitor

- Local potential

- Equipotential lines

Principles and objectives:

The objective of this lab is to study the distribution of the electrostatic field between the 2 copper electrodes modeling a planar capacitor placed inside a tank filled with a copper sulfate solution ensuring electrical conductivity.

Fill the tank with a copper sulfate solution of concentration 0.01 mol/L. The 2 copper plates are connected to a DC power supply delivering a voltage of 6 or 12V for example.

Precautions:

The 2 plates should be as close as possible to the bottom of the tank and the tank should be filled with about 1cm of liquid. The probe tip used to measure potentials should be held vertically for each potential measurement.

Qualitative approach:

Move the probe perpendicularly to the plates and then parallel to the plates, and note the observations.

Quantitative approach:

Measure the potential perpendicularly to the electrodes as a function of distance. It is observed that the obtained curve is of the form U=kx with k =U/d representing the value of the electric field. Then plot on graph paper the potentials between ground and the probe that satisfy U(ground-probe)=constant in order to draw the equipotential lines. Draw the representation of the electric field by drawing lines perpendicular to the equipotential lines. The movable electrode allows obtaining different mappings of the equipotential lines.

- Rheographic tank with mobile electrode (ref 280264) - Power supply 12V/1A (ref 281001) - Set of cords with test tips (ref 284089) - Foxy 2 console (ref 485000) - AS SUP software (ref 000131) Option: - 250g copper sulfate (ref 105245)