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

There are three point charges, q_{1}has a magnitude of 3.00mC (the sign is not known) and is 5.0cm away from P and 13.0 cm away from q_{2}. P is 12.0cm away from q_{2}and the three points form a triangle. The net electric field at point P is entirely in the negative y-direction. The charge for q_{2}is not known.

Determine the magnitude of the net electric field.

2. Relevant equations

E=Q/4∏ε_{0}r^{2}

3. The attempt at a solution

I think you have to use the equation above and then add the 3 values together, but I don't know how to calculate E when I'm only given the value for q_{1}and none of the other points.

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

2. Relevant equations

3. The attempt at a solution

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# Homework Help: Determin the magnitude of the net electric field of three point charges

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