Equation for magnetic moment, E-field and B-field

AI Thread Summary
A magnetic moment is generated when a charge or current moves in a closed loop. The relationship between the magnetic moment and the magnetic field is described by the formula B = [3(m·r)r/r^5 - m/r^3], where r represents vectors and the dot product is indicated by a dot. It is noted that this formula does not produce an electric field (E-field). The discussion emphasizes the vector nature of the magnetic moment and its role in generating magnetic fields. Overall, the connection between magnetic moments and fields is clarified without involving electric fields.
pangsiukwong
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Hi!

When a charge/current moves in a closed loop, a magnetic moment is generated.
Is there any formula for connecting the magnetic moment to E-field and B-field?

Patrick
 
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A magnetic moment m (a vector) produces a magnetic field given by
B=[3(m.r)r/r^5-m/r^3] plus a delta function if r-->0.
The r in the numerators are vectors and . means the dot product.
There is no E field produced.
 

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