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From Faraday’s Law to Today

Ivor Catt. 4th March 2010.

 

 

Looking back in time, I find my progress in developing electromagnetic theory has taken many decades. I have done much work and gathered many insights, but some of the synthesis is only now coming to me.

 

Along with everyone else, I have been guilty of ignoring the magnetic field and concentrating too much on the electric field, and on voltage. We are encouraged to do this because we can measure voltage much more easily than we can measure magnetic field. Take Faraday’s law, the starting point for all of today’s theory. http://www.electromagnetism.demon.co.uk/images/7877.jpg

Faraday did not deliver electric current into the primary of his transformer, and this did not create magnetic field. Rather, he delivered electromagnetic field, which has a magnetic dimension as well as its electric dimension. It approached his transformer at the speed of light, and then reciprocated from side to side of the primary coil at the speed of light. (See animations , Figures 4 and 5  of "Displacement Current" , and Figure 3 . At every stage, it was magnetic field just as much as it was electric field. Or we could say that it was electric field just as much as it was magnetic field. What entered the secondary of the transformer was both magnetic and electric, and what left the secondary and advanced towards the voltage meter was magnetic as well as electric.

 

However, Mike Gibson fell into the same trap when he discussed the one turn transformer (2) , the “prototype” for Faraday’s experiment when he supposedly discovered electromagnetic induction . Like me, Mike did not mention the magnetic field, which obviously exists just as much as the electric field.