Magnetic field and skin effect

AI Thread Summary
The discussion focuses on the limitations of Biot-Savart's law when applied to high-frequency currents, particularly in relation to the skin effect and conductor resistance. It emphasizes that Biot-Savart's law is not suitable for time-varying magnetic fields and suggests using Maxwell's equations for accurate analysis. Participants note that while Biot-Savart can work for certain time-dependent scenarios, it is generally inaccurate for high-frequency applications like antennas. The conversation also highlights the necessity of measuring or assuming specific quantities to infer current flow through a conductor. Accurate modeling of current in conductors at high frequencies requires a deeper understanding of electromagnetic principles.
Vikas_Madhu
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In Biot savart's law we have term for current flowing through conductor. Is there any equation which describes the effects of skin effect, radius of conductor and resistance of conductor on this current with which it is possible to know the current flowing through conductor without practically measuring.
 
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Having screwed this up myself, I can tell you not to try to use the Biot Savart law on high frequency stuff. If you look at any text on it, it will tell you that it's only valid in when the B field is not time-varying. What I believe you need is the full Maxwell's equations, as what you need can definitely be derived from those.
http://en.wikipedia.org/wiki/Maxwell_equations
Alternately, I think I've seen such an equation before; see if this page has what you're looking for:
http://en.wikipedia.org/wiki/Skin_effect
 
...it is possible to know the current flowing through conductor without practically measuring.
What quantities do you know? You have to assume/measure something to infer the current.

FireStorm000,
for high-frequency oscillations, like in antenna, the Biot-Savart formula becomes indeed inaccurate. However, it can be accurate for time-dependent currents, provided the electric field is given accurately by the Coulomb formula (quasistationary processes, like slow capacitor discharge).
 
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