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

What is the angle θ between the electrostatic force on the charge at the origin and the positive x-axis? Answer in degrees as an angle between -180 degrees and 180 degrees measured from the positive x-axis, with counterclockwise positive.

Coulomb constant is 8.98755e9

(Figure attached)

2. Relevant equations

F = kqQ/R^{2}(for answers found in previous question, which was marked correct)

3. The attempt at a solution

In the previous question I was asked to find the magnitiude of the electrostatic force on the charge at the origin (see figure). I found this to be 2.112678794e-9 by calculating the forces between the charges and the origin seperately, and then using a^2+b^2=c^2.

To find the angle between the force and the x-axis I did arctan = (-9.1709694e-10)/(1.90324588e-9) and got -25.7275298 degrees. I plugged it in as both positive and negative, and both answers were wrong. I'm not sure how the "-180 to 180" part of the question changes it, and help would be appreciated. The two values I used in the tangent equation I used to find the correct answer in the question before this one, so I don't see how the angle would be wrong.

Thanks!

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# Homework Help: Finding the angle for an electrostatic force

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