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

[synergix]

Homework Statement

Compute the electric potential energy for the charge configuration shown below.
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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?

 

[LowlyPion]

Sorry your image isn't viewable.

 

[nlightner]

Yes, you are on the right track. To compute the electric potential energy for the given charge configuration, you can use the equation PE= qV, where q is the charge and V is the electric potential. In this case, you will need to calculate the electric potential at each point due to the other charges and then sum them up to get the total electric potential energy. Your attempt at a solution shows that you understand the concept and are using the correct equations. Keep in mind that the electric potential is a scalar quantity, so you can simply add up the potentials at each point rather than using vector addition. Also, make sure to use the correct signs for the charges and distances in your calculations. Good job so far!