All Problems Electric Capacitance, Energy of an Electric Field
Problem 3.127
Determine the interaction energy of the point charges located at the corners of a square with the side \(a\) in the circuits shown in Fig. \(3.29 .\)
3.127. (a) \(W=(\sqrt{2}+4) q^{2} / 4 \pi \varepsilon_{0} a\) (b) \(W=(\sqrt{2}-4) q^{2} / 4 \pi \varepsilon_{0} a\) (c) \(W=-\sqrt{2} q^{2 / 4} \pi \varepsilon_{0} a\)