I've been trying to figure this problem out for quite awhile but am really struggling, help would be much appreciated. Thank you(adsbygoogle = window.adsbygoogle || []).push({});

In the diagram to the right, the net force on the 1.0 mC charge is zero. What is the sign and magnitude of the unknown charge q?

So the diagram is a triangle, which has two charges on the bottom, each 2.0mC, and 8 cm apart. The top is the unknown q, which from the middle of the triangle is 6cm up. And there is a 1.0mC charge in the centre of the triangle which is 3 cm up. (I have attached the diagram)

Based on the measurements given, I'm first trying to come up with the x and y components for each of the forces. And this is where I'm already having difficulties. Q1 is bottom left, Q2 unknown top, Q3 bottom right, Q4 centre

F12 = -F12xcos(theta)- F12ysin(theta)

F13 = -F13x

F14 = -F14xcos(theta)+ F14ysin(theta)

x: -F12cos(theta)- F13 + F14cos(theta) = 0

y: -F12sin(theta) + F14sin(theta) = 0

Can anyone tell me if this looks remotely ok so far?

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# Homework Help: Coulomb triangle

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