SORRY POSTED UNDER WRONG TOPIC = Delete thanks 1. The problem statement, all variables and given/known data Hi, I would appreciate it if someone could help me with this question, im a n00b here Please and thank you Okay heres the question. The particles have charges Q1 = -Q2 = 100nC and Q3 = -Q4 =200nC and distance a = 5.0cm. What are the x and y components of the net electostatic force on particle 3 ? So basically a diagram is given with the question showing the 4 particles equally seperated from each other at a distance of 5.0cm, making a square. And I have to find the force on particle 3. 2. Relevant equations This is the equation I used. F1,3 = (8.854x10^-12) x (Q1 x Q3)/0.0707xR^2 (0.0707 comes from Phyagrous therom) H= (square root) 0.05^2 + 0.05^2 F1,4 = (8.854x10^-12) x (Q1 x Q4)/0.0707xR^2 Fnet = F1,3 + F1,4 = F1,3 + (8.854x10^-12) x (Q1 x Q3)/R^2 Cos 45 (45 degrees middle of square) + (8.854x10^-12) x (Q1 x Q4)/0.0707xR^2 Sin 45 3. The attempt at a solution I have a feeling this is seriously wrong and have made it more complicated than it is. I placed the values into the equation shown and came out with = -79.46 x10^3 + 79.46 x10^3 Heres a site I found afterwards... http://physics.bu.edu/~duffy/PY106/Charge.html I think it might go a little something like that instead^^ If you could help that would be great thanks.