- #1

NicoleKarmo

- 1

- 0

## Homework Statement

Find the electric field and the potential at the center of a square 2.0 cm with charges of +9.0uC at one corner of the square and with charger of -3.0uC at the remaining 3 corners.

## Homework Equations

the sum of Vi= the sum of KQi/ri

## The Attempt at a Solution

I saw that the equation was re-arranged this way but I'm not sure how they arrived there:

E= Ea+Eb+Ec+Ed = Ea+Eb+Ec-Eb= Ea+Ec= (K|qa|/r^2 + K|qc|/r^2) towards C

when you plug in the #'s the answer is 5.4x10^8 N/C toward c.

what I don't understand is how they concluded that that was the formula to use.