Consider an infinite chain of alternating charges ( \(+q,-q,+q,-q \ldots \)) and spacing \(d\). It is known that the interaction energy between two neighboring charges is \(E_{p}=-1~\mbox{J}\). What is the work needed in Joules to remove one of the charges from the chain and place it at infinity?
Hint: \( \ln(1+x)=-\sum_{k=1}^{\infty} (-1)^{k} \frac{x^{k}}{k}\).
by
David Mattingly
