Answer / therion

Because copper has more free electrons than aluminium but
not as much as gold or silver.

Answer / deepak thakur

since copper has high current carrying capacity..
it has low resistance..
it is of smaller in size then aluminium...

Answer / arul

The electrical capacity of any type of cables/wires are
depending on the heat withstand capacity of the material
wich can be calculated with the product of square of
current, Resistance of the material and Total time for flow
of current. I2RT. Resistance again can be calculated as
R=rho*L/A where rho is the resistivity, L is the length and
A is the area of cross section. So for a fixed current flow
and fixed Length of wire the area of cross section of the
cable is directly propotional to the resistivity.
resistivity of copper is 1.68x10 power -8 and that of Pure
Aluminum is 2.82x10 power -8. So.. for a specific current
flow, an aluminum cable size shall be 1.7 times that of
copper cable. This also is not recommented as the Aluminum
resistivity varries with the alloys and even with casting.
2.5 times the size of copper can be recommented for
Aluminum cables. Also as the temporature expansion of
Aluminum is 3 times that of copper. So all the termination
and joining areas shall be treated more sensible that of
copper.

Answer / tariq

Copper has less specific resistance than that of Aluminum.......

Answer / kevin fowke

Copper has a lower resistance than aluminium so for the
same cross sectional area a copper cable will have less
power loss.

why we used servo motor insted of inducation motor?

1 Answers  

what is the voltage regulation for unity and zero power factor?

0 Answers  

If stator & rotor of a 3-phase induction motor have different no. of poles, will the motor run or not??

3 Answers  

State and define norton’s theorem?

0 Answers  

In a Tap changing transformer where is the tap connected , is it connected in the primary side or it is connected in secondary side

8 Answers   Indiabulls,

If auto trip is operated, can you close the breaker.

2 Answers   KSEB, L&T, Siemens,

WHAT IS THE DIFFERENCE B/WDYNAMO&ALTERNATOR?

6 Answers   IOCL,

how to find the 2500 KVA transformer rated primary and secondary volt and current?

4 Answers  

What is dynamo function in DG sets and draw block diagram?

0 Answers   KPR Agrochem,

Due to ferranti effect which power increases at the receiving end?active power or reactive power?

5 Answers  

What are the three major categories of error?

0 Answers  

how to calculate the cable size for LT and HT power cables with detail explanation?

2 Answers   Asset Developments, Bhel,