Two Very Long Parallel Wires in the Xy-Plane, a Distance

question 82

Multiple Choice

Two very long parallel wires in the xy-plane, a distance 2a apart, are parallel to the y-axis and carry equal currents I as shown in the figure. The +z direction points perpendicular to the xy-plane in a right-handed coordinate system. If the left current flows in the +y direction and the right current flows in the -y direction, which one of the graphs shown in the figure below best represents the z component of the net magnetic field, in the xy-plane, as a function of x? (Caution: These graphs are not magnetic field lines.)

• A) 1
• B) 2
• C) 3
• D) 4
• E) 5