The figure below shows two long, straight wires in the xy plane and parallel to the x axis. One wire is at y = -6.0 cm and the other wire is at y = +6.0 cm. The current in each wire is 22 A.
(a) Find the magnetic field on the z axis at z = +7.8 cm if the currents are both in the -x direction.
(b) Find the magnetic field on the z axis at z = +7.8 cm if the current in the wire at y = -6.0 cm is in the -x direction and the current in the wire 1 y = +6.0cm is in the +x direction.
