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**1. Homework Statement**

Consider the four charges in Figure P25.46 http://i137.photobucket.com/albums/q208/infinitbelt/p25-46.gif [Broken] , in which d = 3 cm, q = 4 nC, the +x-axis points to the right, and the +y-axis points up. What is the force on the 1 nC charge at the bottom? Give your answer in component form, using i and j for and , respectively.

**2. Homework Equations**

F 2on1 = (K|q1||q2|)/r^2

F 3on1 = (K|q1||q3|)/r^2

**3. The Attempt at a Solution**

I did for force 2 on 1 :[(9 x 10^9)(5 x 10^-9)(8 x 10^-9)]/(sqrt(0.03^2 + 0.048^2))^2

Then I did tan(theta) = 4.8/3.0 = 57.994 degrees

1.12 x 10^-4 N * sin(57.994) = 9.5 x 10^-5 N

Then for the other force 3 on 1: [(9 x 10^9)(5 x 10^-9)(5 x 10^-9)]/0.03^2 = 2.5 x 10^-4 N

I am confused as to what to do from here. Any ideas?

Thanks!

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