I've been stuck on this relatively simple question for over an hour, can't get the right answer. I think my fundamental understanding of the units involved is flawed, I would really appreciate any kind of clarification as to what I'm doing... okay here goes. I'm given that three charges are at the vertices of an equilateral triangle, with side lengths of 0.8 meters. The charges are given in units of (mu)C, which I understand to be microCoulombs, is that correct? Two of the charges, mainly the left and uppermost ones, are positive; they are +2.4 microCoulombs and +6.8 microCoulombs, respectively. The third charge, on the right, is negative, a -4.2 microCoulombs. I am asked to calculate the electric field at the point of the leftmost (+2.4) charge, due to the other two charges. The answer is expected in vector format, and in kN/C (killoNewtons per Coulomb?). This shouldn't be hard, using the equation for electric field, Ke*(Q/r^2). What I do every time is: convert the microCoulombs to Coulombs by dividing by 1.6 * 10^6. So I have 6.8 * 10 ^ -6 Couloumbs, -4.9 * 10 ^ - 6 Couloumbs, and the third point doesn't matter, since that's where I'm calculating electric field at. Basically then [ Ke * (6.8 * 10 ^ -6 C) / (0.8 m) ^ 2 ], that's the magnitude, and I divide it into x and y components by multiplying by cos(60) and sin(60) respectively. x should be negative (it extends outward from positive charge to the left on the x-axis) and y is also negative (it extends outward from positive charge down on the y-axis). For the other one, it's [ Ke * (-4.9 * 10 ^ -6 C) / (0.8 m)^2]. It lays directly horizontal to the point in question, so no y-component, it's all x-component and it's positive since the negative charge produces a field directed toward itself. Add components, which should produce and answer in C/N, then divide by 1000 to get kN/C. Seems simple, what am I doing wrong? Sorry if the description is too in-depth or not enough so. Please help me someone!!!!!!!!!