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Mitchtwitchita
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Homework Statement
Three charges lie along the x-axis. The positive charge q1 = 10.0 x 10^-6 C is at x = 1.00 m, and the negative charge q2 = -2.00 x 10^-6 C is at the origin. Where must a positive charge q3 be placed on the x-axis so that the resultant force on it is zero?
Homework Equations
F=kq1q2/r^2
The Attempt at a Solution
F23 = -F13
F23 = k(-2.00 x 10^-6 C)q3/-x^2
F13 = -k(10.0 x 10^-6 C)q3/(1.0 m - x)^2
[k(-2.00 x 10^-6 C)q3/-x^2] - [k(10.0 x 10^-6 C)q3/(1.0 - x)^2] = 0
(-2.00 x 10^-6 C)/-x^2 = (10.0 x 10^-6 C)/(1.0 -x)^2
2/x^2 = 10/(1- x)^2
2 - 4x + 2x^2 = 10x^2
-8x^2 - 4x +2 = 0
My quadratic equation doesn't work out so I'm assuming there was a terrible malfunction earlier on. Can somebody please help me out with this one?