Part 5: Electric Field Lines

Now that we have the shape of the equipotential lines, we can easily determine the shape of the electric field lines as the two sets of curves cross at right angles.

Reduced plate separation

To examine the effect of a reduced plate separation on the electric field, we’ll use plate “B” (set  to 6.00 Volts as before) and the spare plate “C” (set to 0.00 Volts, or ground). With this arrangement, the plates are about three times closer than before, but with the same voltage difference. Retrace the 5 volt, 4 volt and 3 volt equipotentials under the positive plate (Plate B) starting from the y-axis. Enter the data in Table 4 in the lab report. Plot those equipotential lines separately, clearly labelling the plot to distinguish from the one made in Part 4.