How Do You Calculate Electric Potential Energy in a Multi-Charge System?

AI Thread Summary
To calculate electric potential energy in a multi-charge system, the total potential energy (TPE) is derived from the contributions of each pair of charges. The formula used is TPE = PE11 + PE12 + (PE13 + PE23), where each PE term represents the potential energy between specific charge pairs. The charges are assumed to be brought in from infinity, with specific values assigned to each charge. The user seeks confirmation on whether their approach and calculations are correct. Clarification on the visibility of the referenced image is also requested.
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Homework Statement


Compute the electric potential energy for the charge configuration shown below.
http://webct6.nic.bc.ca/webct/RelativeResourceManager/Template/CourseMaterials/CourseContent_2007FA/Assignments/PHY060W_Assignment_07_files/image025.jpg"

Homework Equations


PE=-W=qV=q(vb-va)

The Attempt at a Solution



It is assumed that the charges are being brought in from infinity the -3.0 micro coulomb charge is charge one, 5.0 micro coulomb charge is number 3

TPE=PE11+PE12+(PE13+PE23)
TPE= 0J+[(q1KQ2)/r2] + [(q1KQ3)/r1 + (q2KQ3)/r3]

where q1 is charge 1, q2 and Q2 are charge 2, Q3 is charge 3, r1 is the distance between q1 and Q3, r2 is the distance between charge 1 and 2, r3 is the distance between q2 and Q3.

am I on the right track can I simply solve this equation to get the right answer?
 
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