# Homework Help: Electromagnetism, two wires and fields

1. Feb 4, 2010

### Ripperbat

1. The problem statement, all variables and given/known data
Two very long thin wires carrying equal and opposite currents of 103 A are placed parallel to the x-axis at y=0 and z=+-0.5. Calculte the magnetic field B in the x-y plane and determine it's maximum gradient.

2. Relevant equations
I'm having serious trouble understanding the question itself, can anyone clarify?

2. Feb 4, 2010

### kuruman

Sit in front of a table. Let the plane of the table be the xy plane. Let the x-axis be along the top edge of the table facing you and the y-axis be on the table perpendicular to the x-axis and pointing away from you. Imagine one wire 0.5 m above the plane of the table and parallel to the x-axis (the edge facing you). The second wire is 1.0 m directly below the first wire or 0.5 m below the surface of the table.

The problem is asking you two things.
1. Find the magnetic field at some arbitrary point on the surface of the table.
2. Find the maximum rate of change of the magnetic field in part 1 with respect to position.