Answer / sirajudheen nellur

Because in AC there is a phenomenon called skin effect, ie
the AC travels only through outer surface of the cable. It
is the same reason why we use stranded wires for AC

Answer / paridhi jain

because it is concentrated at d surface while dc resistance
is distributed uniformly throughout d conductor

Answer / anil nalla

conductor carries more current on its surface in AC...But in
DC ,current is distributed uniformly.

Answer / paridhi jain

because it is concentrated at d surface while dc resistance
is distributed uniformly throughout d conductor

Answer / m.ravi

skin effect and corona losses will more with frequency and
resistance

Answer / nayeem( cuet)

When DC current passes through any conductor,the current
uniformly distributed over the whole surface of the
conductor. But AC current not distributed uniformly rather
it has the tendency to concentrate. this is known as skin
effect. For this reason AC resistance is greater than DC
resistance of a transmission line.

Answer / mohd. kashan wali

AC resistance is greater than DC resistance.
The reason is:-

In AC, Skin effect occurs which means that current tends to flow through the skin of the wire than through the inner core,so net area of current flow in AC tends to reduce.
And Resistance is inverse proportional to Area, and as the net area of current flow decrease, so NET AC RESISTANCE INCREASES.
Now in DC current, there is uniform current flow.So net area of current flow through conductor is greater than AC,
THUS DC RESISTANCE IS LESS THAN AC

Answer / pawan pal

Ac resistance is high than dc.
Due to corona effect and skin effect ,
Frequency, impedance.

Answer / naresh

in case of ac transmission line, the impedance of the line
may be due to positive ,negative &zero sequence
components.whereas in case of dc there will not be any
effect of either of these components on transmission line.

What are the tests to be done on circuit breaker?

1 Answers  

I am in last year of Engineering.I want to apply for ONGC on GATE based score.They require Certificate of Competency as Electrical Supervisor.How can i get this certificate so I can apply for AEE(ELECTRICAL) in 2016

1 Answers   ONGC,

In pakistan appliances work on 220v at 50hz and in us appliances work on 110v at 60hz what is basic theory to explain it

1 Answers   SNGPL,

Why does not AC excitation use in rotor of AC Generator instead of DC excitation?

2 Answers   A2Z Group,

Why is it not possible to operate a star-delta transformer in parallel with delta-delta transformer?

1 Answers  

HOW WE CALCULATE CURRENT IF THERE ARE NOT PRESENT ANY AMMETER OR MULTIMMETER??????

0 Answers  

What is relation between mu(nought) and epsilon(nought)?

0 Answers  

what are effects of harmonics in the three phase a.c power system ?

2 Answers   AIIMS,

if we convert kw into Ampers,which one formula use by us,pls tell me?

9 Answers   ABB, Essar,

how we design a pannel to start 10HP motor with the help of star delta starter?

0 Answers  

what is slip what is the use of slip?

1 Answers  

1.WHAT IS A SMART CAPABLE DB ( DISTRIBUTION BOX) ? 2. HOW TO DECIDE THE TYPE OF DB TO BE USED ( RECESSED/ PLUG TYPE/ SMART ETC ETC? 3. WHAT IS MILLENEUM BUS BAR USED IN DB? 4.DIFFERENTIATE MCCB AND MCB.

0 Answers