I NEED 2 KNOW WHETHER THE RESISTANCE IN AC AND DC, ARE SAME R
DIFFERENT....IN AC V R DEALIN WID PHASE ANGLE N SAYIN TAT BOTH WERE IN

PHASE(CURRENT N VOLTAGE)....COULD ANYONE SUGGEST THE REASON BEHIND
THIS? IN DC V R SAYIN TAT BOTH WERE HAVIN LINEAR RELATIONSHIP ! SO
JUSTIFY ME WHETHER THE RESISTANCE IN AC AND DC, ARE SAME OR NOT?

Two reasons:
1. Skins effect for individual conductors. See http://en.wikipedia.org/wiki/Skin_effect
2. Proximity effect for bundled conductors. See
http://en.wikipedia.org/wiki/Proximity_effect_ (electromagnetism)
In both cases the resistance increases with frequency due a reduction
in effective cross-sectional area for conduction.
If you meant the resistive component of an arbitrary impedance, then
this is the same for DC or AC. But I suspect you might be struggling
with the distinction between pure (ohmic) resistance and reactances.

One way of looking at it is that dc is simply very, very slowly changing
ac. Unless you are going to explain the difference between dc and ac
with a frequency of
0.000000000000000000000000000000000000000000000000000000000000000001 Hz?
--
Sue

As when studying Fourier. Any repeating waveform can be reduced to the sum
of an infinite number of sin and cosine waves.
And with a sufficiently warped mind, *anything* can be considered a
repeating waveform, including the Big-Bang.... :-)
daestrom

It appears that you are confused between resistance and impedance. The
Impedance for DC is the resistance but for AC it includes the effect of
inductance or capacitance (hence the phase angle) If, in AC the phase angle
is 0- that implies resistance only and this will be somewhat higher than the
DC resistance depending on frequency.
The voltage current relationship is treated as linear in both cases.

--

Don Kelly snipped-for-privacy@shawcross.ca
remove the X to answer

ok frnd we know that Rdc=1.6*Rac....if this is true means , resistor's
resistance value while considering na why we are taking the value of
resistance multiplied wid 1.6....it remains the same in dc and ac
na.....there no change will com or what?

Do you not mean Rac =1.6Rac which is possible due to skin effect as
mentioned by someone else?.
For AC the current tends to flow in the outer part of the conductor while it
is uniformly distributed through the conductor for DC. This means that the
effective area of the conductor is smaller for AC than it is for DC so that
the AC resistance is higher than the DC resistance and the difference is
frequency and conductor size dependent.
It might be a good idea to rephrase your question so that at least some of
the rules of English apply. frnd, wid, com can be guessed at but na is a
mystery so try to avoid word short cuts.

--

Don Kelly snipped-for-privacy@shawcross.ca
remove the X to answer

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