The skin effect dictates that charges tend to flow along the surface of a conductor. And yet resistance of a material is equal to resistivity multiplied by the cross-sectional area of the material divided by the length. Shouldn't it be based on the surface area?
Electronic – If charges flow along the surface of a conductor, why is resistance a function of cross-sectional area
currentresistanceskin-effect
Related Solutions
There is no one answer; you need to consider each possible pairing of wires individually. With symmetry, there are four unique cases. The formula can be found here.
The skin effect is the effective reduction in the cross sectional area of a conductor that carries high frequency AC. The current density is higher on the outside of the conductor than it is an the inside. The actual resistivity of the conductor is still uniform throughout.
Its essentially an example of back emf which is strongest in the middle of the wire produced by the changing magnetic field of the AC.
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Best Answer
The skin effect is an effect of frequency.
At DC there is no skin effect so the resistance is a function of the cross section of the conductor.
As frequency rises, the current tends to decrease at the center of the conductor as you said. For the current to flow only at the surface of the conductor, the frequency of the current should be infinite. In reality there is always current flow with diverse density at different depths of the conductor, but there is never current "only on the surface".