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**1. The problem statement, all variables and given/known data**

A bar magnet floats above another bar magnet. The first has mass u

_{1}and magnetic moment

**m**m

_{1}=_{1}

**k**and is on the ground. The second has mass u

^{^}_{2}and mag. moment

**m**=-m

_{2}_{2}

**k**and is a distance z above the ground, find z

^{^}

2. Relevant equations

2. Relevant equations

I assume I need to calculate the magnetic force between the 2 and equate that to the gravitational force, so;

**B**=(u

_{dip}(r)_{0}/4pi*r

^{3}){3(

**m.r**)

^{^}**r**-

^{^}**m**}

and F

_{B}=IBw

and F

_{g}=-u

_{2}g

**3. The attempt at a solution**

I'm not entirely sure how to begin this question, I think I need to balance out the gravitational force and magnetic force to find the equilibrium position of the floating bar magnet and the magnetic moments will superpose because of the uniform magnetic field, my main problem is using that equation for the magnetic field, I haven't seen it before and I am just going by Griffiths which seems to imply this equation will only work with a circular loop (?)