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

Four point charges have the same magnitude of 3.1 x 10-12 C and are fixed to the corners of a square that is 5.3 cm on a side. Three of the charges are positive and one is negative. Determine the magnitude of the net electric field that exists at the center of the square.

2. Relevant equations

E=k*abs(q)/r^2

3. The attempt at a solution

I set up the equation E=(8.99*10^9)(3.1*10^-12)/(3.75^2).

1.98*10^-3 is not correct

A post I was reading mentioned using the formula E=kq/r....which can be found here: https://www.physicsforums.com/showthread.php?t=151884

Now, my book has a similar picture which mentions an E24 vector pointing at the negative point charge, i'm not sure what i'm doing wrong...any help is welcome.

1. The problem statement, all variables and given/known data

2. Relevant equations

3. The attempt at a solution

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# Electric field of a point charge

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