Calculating Electric Field Components for Discrete Charge Distribution

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clb399
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Homework Statement


Two test charges are located in the x–y plane. If q1 = -3.50 nC and is located at x = 0.00 m, y = 0.680 m and the second test charge has magnitude of q2 = 3.60 nC and is located at x = 1.00 m, y = 0.650 m, calculate the x and y components, Ex and Ey, of the electric field, , in component form at the origin, (0,0). The Coulomb Force constant is 1/(4π ε0) = 8.99 × 109 N·m2/C2.

Homework Equations


E=Kq/r^2

The Attempt at a Solution


So first I converted all of the given data.
q1= -3.5x10^-9 C
q2= 3.6x10^-9 C
r1=.680
r2=sqrt(1.1926)
angle=33degrees using tan^-1(.650/1)

Then I solved for E1y since it is entirely in the y direction:
E1y= K(-3.5x10^-9)/(.680)^2= -68.05

Then solved the x and y components of E2
E2x= K(3.6x10^-9)/(1.1926)^2(cos(33)) = 22.76
E2y= K(3.6x10^-9)/(1.1926)^2(sin(33))= 14.78

Then:
E1y+E2y
E2x
This is my newest answer that I've come up with but all of them have been wrong. I'm not sure what I'm missing or what's going wrong.
 
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I do not have a solutions manual, this is an online assignment. And what direction is wrong?
 
clb399 said:
I do not have a solutions manual, this is an online assignment. And what direction is wrong?

Both, the field of a negative charge should be pointing towards it and that of a positive away from it as a negative charge would attract and a positive repulse a positive test charge.
 
What would the directions change? I have no idea how that helps me in the problem. I understand what you're saying, I just don't see how it applies.