Finding Magnetic Moment from Pull Force

[Matt Klosterman]

For an undergraduate project, I need a magnet with a magnetic dipole strength of 0.3 A*m^2. However, all distributors I can find only list their magnets in terms of "pull force" which appears to be defined as the force between a magnet and a steel plate. How do I find a magnet with the dipole I require? Thanks!

 

[Charles Link]

If I interpret it correctly, the dipole strength for a magnetic dipole current loop is given by $\mu=IA$. For a magnet with magnetization (per unit volume) $M$, and volume $V$ , this also gives a dipole strength of $\mu=MV$. Magnetization $M$ has the same units as $B$, since $B=\mu_o H+M$. Manufacturers will sometimes list the magnetization $M$, and something around $1.0 \, T<M<1.5 \, T$ is reasonably common for a high quality magnet. This means the volume of this magnet is going to need to be $V \approx .2 \, m^3$. Perhaps I have misinterpreted something, because this magnet would be quite large, and might weigh about 1 ton.