Electromagnetics from a quasistatic perspective

American Journal of Physics

Volumn 75, Issue 3, 2007, Pages 230-239

  Larsson, Jonas ^a  

^a UMEÅ UNIVERSITY   (Sweden)

Author keywords

[No Author keywords available]

Indexed keywords

EID: 33947318640     PISSN: 00029505     EISSN: None     Source Type: Journal    
DOI: 10.1119/1.2397095     Document Type: Article

References (39)

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14. It has been tempting to regard ∂B/ ∂t in Faraday's law as a source of an electric field, thereby sometimes causing confusion and objections; currents and charges should be considered as the only sources of electromagnetic fields. The integrals expressing the fields in terms of these sources involve, in general, the retarded time so that the news from the sources propagates with the finite velocity c. In a quasistatic approximation the interactions are instantaneous so this objection is less valid.
15. The static continuity equation together with Eqs. (1) and (2) constitute a quasistatic model without capacitive or inductive effects.
16. ∞.
17. We consider systems where the charges and currents do not extend to spatial infinity and may use as boundary conditions that the fields approach zero sufficiently fast far away.
18. f, differs from Eq. (15) if there is a nonvanishing polarization current ∂P / ∂t. Ampère's law is, strictly, speaking, a static equation, and we prefer to use Eq. (15) as a time-dependent generalization with the same name.
19. As in Ref. 2 we use the names Ampère's law for Eq. (15) and Ampère-Maxwell for Eq. (13). Then it seems natural to use the name Ampère-Darwin for Eq. (16).
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32. 3 when r→∞.
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34. There are many PDE solvers that are suitable for electromagnetic simulations. In Ref. 38 the program FlexPDE is used. I use COMSOL Multiphysics with the Electromagnetic module. Information about these programs may be found at 〈http://www.pdesolutions.com/〉 and 〈http://www.comsol.com/ 〉.
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