Hi, I have a question about a problem. Four different charges are placed on the corners of a square, and then a fifth one is placed on the center. I need to find the speed this fifth charge would have at a great distance. The total energy of the system should be the sum of the work to bring each charge to the square right? So, the total work equals U, and the velocity of the charge can be found from U=Ek, U=mv^2/2. It seems right to me, but I just can't get the right answer. I appreciate the help, thanks.