I'm not sure that I really understand this question:(adsbygoogle = window.adsbygoogle || []).push({});

How much energy is needed to place four positive charges, each of magnitude +5.0mC, at the vertices of a square of side 2.5cm?

what I was thinking is that V = kQ/r

And since all the charges are equal, and the same distance apart V1=V2=V3=V4 = (9x10^9)(5x10^-3C)/2.5x10^-2m = 1.8x10^9V

Vnet = V1 +V2 + V3 + V4 = 7.2x10^9V

However I haven't taken into account the diaganols - do I need to?

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# Homework Help: Energy of charges in a square

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