# Doing The Electric Dance

Three identical conducting spheres are located at the vertices of an equilateral triangle $$ABC.$$ Initially the charge of the sphere at point $$A$$ is $$q_{A}=0$$ and the spheres at $$B$$ and $$C$$ carry the same charge $$q_{B}=q_{C}=q.$$ It is known that the sphere $$B$$ exerts an electrostatic force on $$C$$ which has a magnitude $$F=4~\mbox{N}.$$ Suppose an engineer connects a very thin conducting wire between spheres $$A$$ and $$B.$$ Then she removes the wire and connects it between spheres $$A$$ and $$C.$$ After these operations, what is the magnitude of the force of interaction in Newtons between $$B$$ and $$C?$$

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