Question

A wire of resistivity ρ is stretched to double its length, then its new resistivity will be half be 4 times be double not change

Answer 1

Answer:

4 times

Explanation:

▪️Resistance= Resistivity x length/area

▪️When the wire is stretched to double the length , the area of cross section gets reduced to half.

▪️So

▪️New Resistance = Resistivity x 2 length/area/2

▪️i.e,

▪️New resistance = (Resistivity x length/area)x 4

▪️i.e, New resistance = Resistance x 4

▪️So when the wire is stretched, the resistance multiplies by four times.

Hopes it help you❤️❤️

Answer 2

Explanation:

When the wire is stretched to double the length , the area of cross section gets reduced to half. So when the wire is stretched, the resistance multiplies by four times

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