1. The problem statement, all variables and given/known data The four wires that lie at the corners of a square of side a=5.10cm are carrying equal currents i=2.40Amps into (+) or out of (-) the page, as shown in the picture. Calculate the y component of the magnetic field at the center of the square. 2. Relevant equations B field = u0 I / (2 pi r) a^2 + b^2 = c^2 3. The attempt at a solution Since at the origin there are two fields pointing up and to the right at 45 degrees, and two fields pointing up and to the left at 45 degrees, the total y component is 4 * sin45 * u0 I / (2 pi r). r = sqrt [ (a/2)^2 + (a/2)^2 ] or 1.697 u0 = 4pi*10^-7 Using these numbers I got 8*10^-7 T but this is wrong. Can someone tell me what I'm doing wrong? THanks! Diagram is attached.