PASCO ES-9060 Charge, Equipotential and Field Mapper - Manual (Page 10)

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Model No. ES-9060 Charge, Equipotential, and Field Mapper
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3. Continue to move the probe, but only in a direction which
maintains the voltmeter at the same reading. Continue to mark
these points.
4. Connect the points to produce an equipotential line.
Part IV: Plotting Field Gradients
To plot field gradients (field lines), you will place the two leads of the
voltmeter on the conductive paper, side-by side, at a set distance of
separation (one centimeter is a useful separation to use). (Note: When
plotting field gradients, neither lead of the voltmeter is connected to an
electrode.) It is best to tape two leads of the voltmeter together for this
procedure (See Figure 7). The technique is to use the voltmeter leads
to find the direction from an electrode that follows the path of greatest
potential difference from point to point.
NOTE: Do not attempt to make measurements by placing the leads on
the grid marks on the conductive paper. Touch the voltmeter leads
only on the solid black areas of the paper. It may be necessary to use a
higher voltmeter sensitivity for this measurement than was used in
measuring equipotentials.
1. To plot the field lines on the conductive paper, place the voltmeter lead
(connected to ground) near one of the dipoles.
2. Place the other voltmeter lead on the paper and note the voltmeter
reading.
3. Now pivot the lead to several new positions while keeping the
ground lead stationary (See Figure 7). Note the voltmeter readings
as you touch the lead at each new spot on the paper.
Figure 7: Using the probe to find the highest
potential
Ground lead
for voltmeter
Electrode to
voltage source
(battery or
power supply)
Tape
Conductive
paper
Area to probe
to find the highest
potential difference