(adsbygoogle = window.adsbygoogle || []).push({}); 1. The problem statement, all variables and given/known data

Three charges are located in the x-y plane (see plot below), with Q1 = -6.00 μC, Q2 = 5.00 μC and Q3 = -3.00 μC. Note that the charges are located at grid intersections points.

*I couldn't put the grid on here, but the points are Q1 = (-2,-4), Q2 = (-2, 2). and Q3 = (3, -4)

a) Calculate the total electrostatic potential energy.

b) Calculate the work required (by external forces) to transport Q3 from its location on the figure to infinity.

2. Relevant equations

PE = k[(Q1Q2/r12) + (Q1Q3/r1r3) + (Q2Q3/r2r3)]

3. The attempt at a solution

I got part a) to be -.0299 J, which was right. This is what I did for the second part:

k[(Q1Q3/r1r3) + (Q2Q3/r2r3)]=

=k[(-15/√61) + (18/5)]

=1.51x10^10 J.

I have tried both this and its negative counterpart, neither yielding a correct answer. Please help!

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# Homework Help: Three point charge in a plane (electricity in physics II)

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