Question

Two very long, straight, parallel wires separated by distance d carry currents of magnitude I in opposite directions. Find the magnetic field at a point equidistant from the lines, with a distance 2d from each line. Draw a diagram showing the direction of the magnetic field. One very large conducting plate coincides with the x-y plane.

Answer 1

We know that the magnitude of the field is given by As the distance and the current magnitude are same the magnitude of the fields are same. Applying right hand rule, it is easy to see that the fields add up between the wires. So we have 2 2Tx2d μο! 4d 2d