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Sick of ridiculous KVL infighting

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SandyCox:
The point is that circuit theory is a (very useful) abstraction. The notions of electric and magnetic fields are not part of this paradigm. There is no Faraday’s law or Ampere’s law within the paradigm of circuit theory.
In circuit theory, components are represented by symbols and the “wires” form a graph, describing the way in which the components are connected. Components are represented by their terminal properties, in the form of mathematical equations, i.e.
v = Ri,
i = C dv/dt,
v = L di/dt,
etc.
While these equations are derived from the laws of electromagnetism, the actual physics of how the components work do not form part of the paradigm. Semiconductors are also represented by symbols and their terminal properties. Circuit theory tells us absolutely nothing about the underlying semiconductor physics.
The loops we draw in circuit theory and the actual physical loops are not the same. The physical loops have parasitic resistance, inductance and capacitance. Magnetic fields can couple into the physical loops. We can model these effects, to a certain extent, by creating symbols and equations that capture the underlying physics. For example, the equivalent circuit of a transformer.
Within the paradigm of circuit theory, Kirchhoff’s laws are perfectly valid.
Circuit theory remains an extremely valuable abstraction. Most of us simply would not be able to design circuits if we had to take the full Maxwell’s equations, and semiconductor physics, into account at every step of the design process.
Dr Lewin, with all respect, you are wrong!
Apparently, you are unaware of the fact that circuit theory is an abstraction. You are mixing concepts from two different paradigms.



thinkfat:
And back to square one...

snarkysparky:
Aren't we talking about a completely static situation.  No field quantities are changing with time?  That was the original question?

If so isn't the line integral of E * dl    path independent?

SandyCox:
Not static. Note the di/dt and the dv/dt in the equations.

There is no concept of electric field within the paradigm of circuit analysis. It is only introduced in the next level of understanding. Also no concept of distance or path along which to integrate. Just symbols described by their terminal properties and links (virtual wires) connecting them.

snarkysparky:
The original problem is a battery powering a light bulb.  So yes the fields have no time varying component after the transient.   

And after the transient the power flows entirely in the wires.   

Veritasium is WRONG in his statement.

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