Faraday's Law vs Kirchhoff's Law !!

studiot

Joined Nov 9, 2007
4,998
Steve,

I would agree wholeheartedly that 'Field' theories are more comprehensive than 'Circuit' theories, just less convenient for everyday use.

Circuit theories were developed a good 60 - 30 years before field theories

1800 - 1820 Volta, Coulomb and Ampere

1830 Faradays law

1873 Maxwell's Treatise

Of course the process has not stopped there.

In turn Maxwell has been generalised by special relativity and extended to 4 space in Tensor language with the Maxwell Stress Tensor. In this format all four original equations are combined into one.

The reference in Post 2 by 'Thatoneguy' goes a long way towards my roadmap, though I would hope to condense mine a bit.

http://forum.allaboutcircuits.com/showthread.php?t=21231
 
Last edited:

Thread Starter

mik3

Joined Feb 4, 2008
4,843
In these thought experiments wires have zero resistance, which is how Steve and I calculated infinite current.
I think you can get an infinite current theoretically in a DC circuit. If you consider AC circuits, I believe you cannot get infinite current due to the inductance of the wires even if they have zero resistance.
 

studiot

Joined Nov 9, 2007
4,998
I have attached an extract from

Electricity and Magnetism (1951)

By Francis Weston Sears, a well known american physics professor and author.

His description of Kirchoff's laws is self explanatory, but reading chapter 5 of this book explains the difference between EMF and PD very well as it explains the relationship between the electric field integral and emf.

His other more general physics books also contain a more condensed version of the same information.
 

Attachments

steveb

Joined Jul 3, 2008
2,436
His description of Kirchoff's laws is self explanatory, but reading chapter 5 of this book explains the difference between EMF and PD very well as it explains the relationship between the electric field integral and emf.
Very good!. His definition of Kirchoff's Law's match that in Maxwell's Treatise. In my view, these are the best definitions available.
 
Last edited:
Top