Calculatin units for theoretical magnetic point charge

AI Thread Summary
The discussion revolves around the theoretical concept of a magnetic monopole and the necessary modifications to Maxwell's equations, particularly regarding the divergence of the magnetic field. The user struggles with determining the correct units for the theoretical magnetic point charge, qm, and magnetic charge volume density, ROm. Initial calculations lead to confusion about the dimensionality of ROm, suggesting it might be an area density rather than a volume density. A participant clarifies that the correct unit for ROm is Newtons per Tesla per cubic meter, which resolves the user's confusion. The conversation highlights the complexities of integrating magnetic concepts into existing electromagnetic frameworks.
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Hi,

So, assuming the theoretical existence of a monopole, we would have to alter the maxwell equations to give the magnetic field a divergence, and also to ensure that the divergence of the curl of the electric field is still zero we would have to add a term.

The altered divergence of B would have to be
div(B) = mu0 * ROm

mu 0 being magnetic permeability and ROm being magnetic charge volume density.

I'm having trouble figuring out what the units for the theoretical magnetic point charge, qm, would be - I've figured that the units for the point charge density ROm would be Newtons/(Tesla*meters^2), which doesn't make sense to me - here's how I got it

div(B) => units Tesla/meter
Mu0 has units T/A
so ROm must have units A/m, which equates to Newtons/(Tesla*meters^2)...this doesn't make sense to me because it should be a volume density, not an area density, right?

ALSO, if you try to make an analogy to electric field - E has units of Newtons/Coulomb, and the charge unit is Coulomb - so therefore, if B has units of Tesla, then qm should have units of Newtons/Tesla. Which I guess makes sense, somewhat. HOWEVER, if you do it formally, integrating both sides of the new div(B) equation, you get that the units [qm]=(Newtons*meters)/Tesla.

Yet, with the two results that I did get, the q = ro*V rule is conserved (1/m^2 in ro, *m in q, so m^3 = V is the factor by which they differ)...in short, I've confused myself and don't know what to do.

If someone could point out a mistake in my calculations, or point me in the right direction, I would appreciate it!

Thanks muchly.
 
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Hi
The unit of \mu_{0} shall be
[\mu_{0}]=\frac{mT}{A}
and therefore the unit for \rho_{m} is
[\rho_{m}]=\frac{N}{Tm^{3}}

Hopefully this will clear up things for you
 
Oh, SNAP. Thank you!

What a silly mistake.
 
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