Sorry, forgot to include the actual question. The question asks for the magnitude and sign of the third charge. I don't really understand the wording of this question. That is, should I assign another variable for the distance from the third charge? As well, is the magnitude of the third charge...
Homework Statement
Two point charges q and 4q are distance L apart and free to move. A third charge is placed so that the entire three-charge system is in static equilibrium.
Homework Equations
\SigmaF=0 This is the equation for static equilibrium
\vec{E}=q/4\pi\epsilon_{0}r^2
The...