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## Homework Statement

In a region of two-dimensional space, there are three fixed charges: +1 mC at (0, 0), −2 mC at (15 mm, -2 mm), and +3 mC at (-5 mm, 15 mm). What is the net force on the −2-mC charge?

? magnitude

? direction ° counter-clockwise from the +x-axis

## The Attempt at a Solution

3mc = point 1

1 mc = point 2

-2 mc = point 3

length (1-3) = 26.25 mm

length (2-3) = 15.133 mm

length(1-2) = 15.811 mm

angle at point 3 is 32.5 degree using the sss triangle formula

F(1to3) = k *q1* q3 / l^2

Fx13 = F(1to3) Cos(32.5)

Fy13 = F(1to3) sin(32.5)

F(2 to 3) = k *q2* q3 / l^2

Fx23 = F(2to3) Cos(32.5)

Fy23 = F(2to3) sin(32.5)

Fx13 + Fx23 = Fxnet

Fy13 + Fy23 = Fynet

rad (Fxnet ^2 + Fynet^2 ) = Fnet which is the magnitude but it seems like i'm off by few points the answer has to be pretty close since i have to plug it into the system. Does anyone know where i made the mistake?