Doubts on Skin effect & Electricity

AI Thread Summary
Skin effect limits the penetration of electromagnetic waves in conductors, but high-voltage transmission lines, often exceeding 700,000 volts, effectively transport energy over long distances. The alternating electric field generated at the source is sufficient to drive electrons through conductors, even over thousands of miles. While skin effect does occur, the diameter of power line conductors is small compared to the skin depth at typical frequencies, minimizing losses. The energy is primarily transmitted as an electromagnetic wave between conductors, described by the Poynting vector. Understanding these principles clarifies how electricity can be efficiently delivered across vast distances.
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Hi all! This is my first post :D

I came across skin effect which blocks propagation of an em-wave within a conductor...
But doesn't the energy generated at an electric plant reach our house through conductors flowing for over a 1000 miles sometimes?

If I have to consider it just as an alternating voltage/electric field which makes the charge carriers to flow such long distance, then I have these 2 doubts:
1. Can just 11000 volts be sufficient for pulling / pushing electrons in the conductor after thousands of miles from the source?
2. Even though it is an alternating electric field at the source, while propogation, there will an alternating magnetic field around the conductor which makes it an em wave. And now the same skin effect should work here to to limit the propagation to just a few millimeters or cms...

Thanks in Advance for whoever clears my doubts :P
 
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The interstate power line voltage in the U.S. is often over 700,000 volts. See
http://en.wikipedia.org/wiki/Overhead_power_line
Higher voltage reduces the current. The power line conductor diameter is small relative to the skin depth at 60 (or 50) Hz, so the skin loss is small. The actual power is carried in an em wave between the power line conductors (the Poynting vector), because the energy flow (magnitude and direction) is the vector cross product of the magnetic field and the electric field.. See
http://en.wikipedia.org/wiki/Poynting_vector
Bob S
 
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