Solving a problem in physics section 73 point 64 electr

Solving a problem in physics section 73 point 64 electr

64. Three identical positive charges Q = 10−9 C each are located at the vertices of an equilateral triangle. What negative charge needs to be placed in the center of the triangle so that the attractive force on its side balances the forces of mutual repulsion of the charges at the vertices?

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