The potential at point P is calculated by adding together the potentials due to both charges.
| (13) |
According to equation (7), the corresponding electric field is
| (14) |
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The equipotential lines and the electric field vectors are sketched below for separation distance 2a = 1 m.
Please note that the lengths of the arrows in this plot are not exactly to scale. The reason for this is that a rescaling of the vectors had to be performed to get useful field information out of this graph.
If you were to plot this potential function in
three-dimensional space such that the potential V(x,y) was
plotted on the z-axis, what would be the resulting shape?
Answer
Now go on to get an intuitive feel for two point charges, using our charge applet.