Superpositions of electrostatic forces

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SUMMARY

The discussion focuses on solving for the unknown charges of particles P2 and P3 in a system where three charged particles exert no net force on a charged particle placed at the origin. Particle P1 has a charge of 5.00 μC, while the charges of P2 and P3 are to be determined using electrostatic force equations. The net horizontal and vertical forces at the origin must be zero, leading to the equations K*Q*Q1*cosθ1/(d1)^2 = K*Q*Q3*cosθ3/(d3)^2 for P3 and K*Q*Q2/(d2)^2 = K*Q*Q1*sinθ1/(d1)^2 + K*Q*Q3*sinθ3/(d3)^2 for P2. The participant struggles with the calculations, particularly arriving at incorrect values for Q2 and Q3.

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Homework Statement



Three particles P1, P2, and P3 are located at the points (−2.00, −1.00), (0, 2.00), and (3.00, −1.00), respectively. P1 has a charge of 5.00 μC, but the charges of P2 and P3 are unknown. However, the three particles exert no net force on a charged particle that is placed at the origin. You are asked to find the unknown charges. (a) Use the fact that the net horizontal force on the particle at the origin is zero to find the unknown charge on P3. (b) Then use the fact that the net vertical force on the particle at the origin is zero to find the unknown charge on P2.

Homework Equations



Fnet = (Kq1q2)r2

K = 9*109

The Attempt at a Solution



I am at a loss on where to go with this one. I have tried about 10 different things but keep getting stuck with unsolved variables.

I also attached a drawing i did with some numbers for angles and such that i came up with.

Any help would be greatly appreciated!
 

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From the given hint you can write
K*Q*Q1*cosθ1/(d1)^2 =k*Q* Q3*cosθ3/(d3)^2. where q is the charge at the center.You have already found θ1 and θ3. So find Q3.
Similarly
kQ*Q2/(d2)^2 =K*Q*Q1*sinθ1/(d1)^2 + k*Q* Q3*sinθ3/(d3)^2. Find Q2.
 
This is one of the methods I used and I kept coming up with 9*10-6 which is wrong so, I don't know what to do. Maybe my math is wrong.

([STRIKE]K[/STRIKE] (5*10-6) [STRIKE]Q0[/STRIKE] cos (26.56)) / (2.23)2 = ([STRIKE]K [/STRIKE]Q3 [STRIKE]Q0[/STRIKE] cos(18.43)) / (3.16)2
 

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