Charges of are located at both and , and a charge of is located at on the y-axis. This arrangement of charge can be visualized as two opposing dipoles plus a charge at the center.
a) Find the electric field (magnitude and direction) at an arbitrary point on the x-axis.
b) What are the first two nonzero terms in the electric field
evaluated far from the charges, i.e. - for ? Your answer
should be a series of terms in inverse powers of .