I'm stuck on the following problem: Point charges of q_1=-12nC are placed at (-4,0) cm and (4,0) cm. Determine the magnitude of the electrostatic force on a third charge of q_2=20nC placed at (0,8) cm. So because of symmetry I figured that the x-components of the forces will cancel each other and the total force will be 2 times the y-component. So I did 2*k*q_1*q_2*sin63.4/(0.04^2+0.08^2) and got 4.8e-4 N but the answer is supposed to be 3.1e-8 N. Any help would be appreciated, thanks.(adsbygoogle = window.adsbygoogle || []).push({});

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# Homework Help: Coulomb's Law

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