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- Thread starter carmatic
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- #1

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- #2

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- #3

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as i have said, it only contains information on the force between 2 magnets, not between a magnet and a piece of ferromagnetic material

- #4

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Any luck with this?

I'm looking for this answer as well.

I'm looking for this answer as well.

- #5

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The force between magnets as a mathematical expression is complicated.

What I have found is the force between magnetic diople moments.

The only source that I remember specifically is wikipedia:

http://en.wikipedia.org/wiki/Magnetic_moment#Forces_between_two_magnetic_dipoles

which gave the force acting on [itex]\vec{m}_{2}[/itex] as being

[itex]\frac{3\mu_{0}}{4\pi \left\|\vec{r} \right\| ^{5}} \left[ (\vec{m}_{1} \cdot \vec{r})\vec{m}_{2} + (\vec{m}_{2} \cdot \vec{r})\vec{m}_{1} + (\vec{m}_{1} \cdot \vec{m}_{2})\vec{r} - \frac {5 ( \vec{m}_{1} \cdot \vec{r} )( \vec{m}_{2} \cdot \vec{r} ) \vec{r} }{ \left\| r \right\| ^{2}} \right] [/itex]

with [itex]\vec{m}_{1}[/itex] and [itex]\vec{m}_{2}[/itex] being the two magnetic dipole moments, and [itex]\vec{r}[/itex] is the displacement vector from the location of m_{1} to m_{2}

What I have found is the force between magnetic diople moments.

The only source that I remember specifically is wikipedia:

http://en.wikipedia.org/wiki/Magnetic_moment#Forces_between_two_magnetic_dipoles

which gave the force acting on [itex]\vec{m}_{2}[/itex] as being

[itex]\frac{3\mu_{0}}{4\pi \left\|\vec{r} \right\| ^{5}} \left[ (\vec{m}_{1} \cdot \vec{r})\vec{m}_{2} + (\vec{m}_{2} \cdot \vec{r})\vec{m}_{1} + (\vec{m}_{1} \cdot \vec{m}_{2})\vec{r} - \frac {5 ( \vec{m}_{1} \cdot \vec{r} )( \vec{m}_{2} \cdot \vec{r} ) \vec{r} }{ \left\| r \right\| ^{2}} \right] [/itex]

with [itex]\vec{m}_{1}[/itex] and [itex]\vec{m}_{2}[/itex] being the two magnetic dipole moments, and [itex]\vec{r}[/itex] is the displacement vector from the location of m

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- #6

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- #7

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Anyways, unless you have a very simple system (such as a uniform magnetic field and a ferromagnetic plate), the math you will need to solve your problem can be quite messy.

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