(adsbygoogle = window.adsbygoogle || []).push({}); 1. Two point charges q and 4q are at x=0 and x=L, respectively, and free to move. A third charge is placed so that the entire three-charge system is in static equilibrium.

Two point charges q and 4q are at x=0 and x=L, respectively, and free to move. A third charge is placed so that the entire three-charge system is in static equilibrium.Two point

2. Coulomb's Law

3. I know the answer is 0.444q, and I know how to get it:

k*q*Q3/(0.333L)^2 = k*q*4q/(L^2)

But why is 1/3 *L used in the left side of the equality? If the magnitude of the charge on the far right is 4q and that on the left is q, why isn't the middle particle with charge Q3 1/4 as far from q1 as the 4q particle?

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# Homework Help: Electrostatics - finding magnitude of a third charged particle

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