Answer / rahul

In an ac system voltage and current fluctuates. In DC it is
constant it has no frequency. In an ac system the current
flows more in the outer portion of a conductor than in the
inner portion. This is known as skin effect. In order to
reduce skin effect, conductors are stranded as is the case
in ACSRs. Conductor resistance, frequency, capacitance and
inductance of the cable are a function of skin effect.

Answer / sanjeevibp

The derivation of R and X assume uniform current density
thr the cross section of the conductor.as the hertz
increase from zero,current densityincreases near the
conductor surface and decrease as the center of the
conductor approached.this effect is know as skin effect.in
dc uniform current density occur only when the frequency
is zero.

Answer / mahipal

Skin effect is effect in which current flows more on skin
rather in centre i.e not uniform distribution of current.
This happens due to fact that inner part of conductor has
higher inductance as compared to outer so net inpedance is
more so less flow of current in centre.

Answer / shamim

The tendency of AC to concentrate near the
surface of a conductor is known as skineffect.

All electric currents generate magnetic fields that in turn
can affect the current . In a direct current case
everything is constant and so nothing seems to happen. With
an alternating current, however, there is a delay in the
magnetic field's response to the change in current and
the 'old' magnetic field tends to push the current towards
the outside of the conductor.

Answer / gnanasekaran

we know R=pl/a: a= area of conductor.
If a increases r reduces & vice versa.

middle of the conductor a is low so high resistance so here
is no current flow and vice versa

Answer / suresh reddy

SKIN EFFECR WILL OCCUR ONLY IN AC CABLE & THIS PROBLEM WILL
APPEAR IN SOLID CONDUCTOR
EX-- CURRENT ALWAYS TENDS TO FLOW LOW RESISTANCE PATH SO
THAT HERE THE ELECTRONS ALWAYS TRYS TO FLOW IN WIDE AREA
THAT IS THE OUTER SURFACE OF THE CONDUCTOR BECAUSE INNER
SURFACE HAVING HIGH RESISTANCE AS COMPARED TO OUTER SURFACE
FINALLY I WOULD LIKE SAY THAT TENDENCY OF CURRENT FLOW ON
SURFACE OF THE CONDUCTOR IS GREATER THAN INNER SIDE

TO REDUCE SKIN EFFECT

1 BY USING STRANDED FLEXIBLE COPPER CABLE INSTED OD SOLID

Answer / tarkeshwar

when dc current flow in the conductor it distribute inner &
outer equaly while in case of ac the current flow in
conductor is high on outer surface & low on inner suraface
due to this resistanc increase in inner surface, this is
known as skin effect.

Answer / adnan khattak

The tendency of an alternating current to concentrate near
the surface of a conductor is called SKIN EFFECT.

no skin effect is not absent in d.c system.skin effect is
present in d.c system but present internally to the
conductor because frequency of d.c is zero as compared to
concentrate internally( A.C) to the conductor.

Answer / ashli

y the surface resistance becomes more when ac s applied

Answer / biswajit ghosh

AC current tends to avoidtravel through the centre of solid
conductor.electrons switching directions of flow,on other
hand ,tends to avoid travel through the very middle of a
conductor, limiting the effective cross-sectional area
available . the skin effect becomes more pronounced as
frequency increase.

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