3. The distance d between two point charges Q1 = 180 nC and Q2 = 720 nC is equal to 60 cm. Determine the point where you want to put a third charge Q3 so that the system of charges are in balance. Determine the magnitude and sign of the charge. Stability or instability is the equilibrium?

Detailed solution. Decorated in Microsoft Word 2003. (Target decided to use formula editor)