Answer / abhisek

AC resistance is more than dc resistance [almost 1.2
times]for a certain value of current.

Answer / sureshapgenco

DC resistance is due to opposition because of conductor
property only where as AC resistance is due to both
opposition because of conductor property and skin effect.

Answer / engineering.force

the dc resistance remains constant provided the external
conditions like temperature, moisture, pressure etc. do not
change. the dc resistance does not have any relation
whatsoever to the frequency as there is no frequency for the
dc supply. the current flows uniformly through the cable and
for most cases, the current density at all points is the same.

the ac resistance is frequency dependent. it do not remain
constant with variation in frequency. the self inductance
and mutual inductance of the transmission line play a role
in defining the ac resistance of the transmission line. if
frequency is increased, the resistance of the core of cable
will increase. the current density is not uniform at all
points in the conductor. also, the effective surface area of
the conductor will reduce with increase in the frequency.
this is called skin effect.

Answer / susy

ac resistance comes into picture only at higher frequencies
and it is more than dc resistance by a factor depending on
tthe frequency

Answer / engr khan

AC Resistance
In Simple words, Resistance in AC circuits is called
Impedance. Or
The Overall resistance (Resistance, Inductive reactance and
Capacitive reactance) in AC circuits is called Impedance (Z).


DC Resistance
We know that there is no concept of Inductive and Coactive
reactances in DC Circuits. i.e. capacitive and inductive
reactances in DC circuits zero because there is no
frequency in DC circuits, i.e. magnitude of DC current is
constant. Therefore, only the original resistance of wire
comes into play.
Reference:
http://www.electricaltechnology.org/2014/01/what-is-difference-between-ac-and-dc-resistance.html

Answer / harikrushna adalja

DC

You can easily work with resistance in DC circuits
because DC is a steady, constant flow of current. The
relationships between resistance, voltage, current and power
come directly from Ohm's Law.

AC

In contrast to DC's constant flow, AC alternates between
negative and positive peak values 60 times a second. The 110
volt AC is 110 volts only at its momentary maximum. Though
Ohm's Law applies to AC at any given instant, you determine
power and heat by finding an average current value.

Answer / bereket

In contrast to DC's constant flow, AC alternates between
negative and positive peak values 60 times a second. The 110
volt AC is 110 volts only at its momentary maximum. Though
Ohm's Law applies to AC at any given instant, you determine
power and heat by finding an average current valu

Answer / foysal ahmmed

When ac current flows through any wire, there create a dynamic magnetic field which is known as inductance. Dc current can create a static magnetic field.so,ac resistance is greater than dc resistance.

Answer / ashok choudhary

A.C. resiatance=1.2(D.C. resistance)

In tranformer winding Connection Like Dyn1 ,so LV lags Hv by 30 deg and Dyn11 LV lead HV by 30,so how do this lagging and leading afffect the transformer??

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