Answer / anil singh

As given R1 = L/A ohms
Lenth of cable = L Meter
and Cross Section Area supposed = A sqm
if the same streached to double length
now length of cable = 2L Meters
and Cross section area = A/2
Hence new Resistance of the wire will be R2=2L/(A/2)
R2 = 4 L/A = 4 R1
i.e. four times of earlier

Answer / sasi karthick a

Not exactly, while streching the wire not only the length
but cross sectional area also changes. So it also depends
on both after streching.

Since R=(pl)/A.

Answer / qureshi majid

As the resistance is directly proportional to the length,so
the resistance of wire will be increased if we increase the
length

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