# Magnetic Dipole Moment

1. May 1, 2008

### sotnet

Guys,

I don't quite understand the concept of magnetic dipole moment as a vector.

Suppose we have a magnet (like a rod) in 3 dimensional space. North pole at (0, 0, 0) and South pole at (0, 1, 0).

How would the magnetic dipole vector $$\vec{m}$$ be oriented?

Thanks.

2. May 1, 2008

### Peeter

Probably because it doesn't make much sense as a vector. Roughly speaking, it probably better described as a plane (bivector) quantity. ie: the vector is just the normal to the plane that the current is circulating in. You can describe this plane and the orientation of the current using this normal vector (often called the dual of the plane), or can describe it as an oriented plane directly (bivector).

As to your specific equation of how this vector is oriented with your example poles, it appears that

http://en.wikipedia.org/wiki/Dipole