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djsourabh
Jul8-11, 02:14 AM
What is scientific reason behind skin effect of conductors?

berkeman
Jul8-11, 10:35 AM
What is scientific reason behind skin effect of conductors?

Let us know if you still have specific questions after reading this introductory article:

http://en.wikipedia.org/wiki/Skin_effect

.

djsourabh
Jul13-11, 04:20 AM
The AC current density J in a conductor decreases exponentially from its value at the surface JS according to the depth d from the surface, as follows:

where δ is called the skin depth. The skin depth is thus defined as the depth below the surface of the conductor at which the current density has fallen to 1/e (about 0.37) of JS. In normal cases it is well approximated as:
.
where
ρ = resistivity of the conductor
ω = angular frequency of current = 2π × frequency
μ = absolute magnetic permeability of the conductor

courtesy from wikipedia
how these equations came from?

djsourabh
Jul13-11, 04:23 AM
Let us know if you still have specific questions after reading this introductory article:

http://en.wikipedia.org/wiki/Skin_effect

.

The AC current density J in a conductor decreases exponentially from its value at the surface JS according to the depth d from the surface, as follows:

where δ is called the skin depth. The skin depth is thus defined as the depth below the surface of the conductor at which the current density has fallen to 1/e (about 0.37) of JS. In normal cases it is well approximated as:
.
where
ρ = resistivity of the conductor
ω = angular frequency of current = 2π × frequency
μ = absolute magnetic permeability of the conductor

courtesy from wikipedia
how these equations came from?

djsourabh
Jul13-11, 04:32 AM
But actually the inductance L increases hence current decreases,
then why the ac 'resistance' is calculated as
Rac =1.6*Rdc ?
&
what happens to the power factor?