Consider three straight infinitely long (parallel to each other), equally spaced wires (with distance d), each carrying a current i in the same direction.
assume the three wires are coplanar. (eg. they are lying on the x, y plane where z = 0) , if the middle wire is rigidly displaced a very small distance x (x < < d) upward(in the z direction) while the other two wires are held fixed. analyze and describe the resulting motion of the middle wire. be specific in terms of magnetic field and gravity.