Question

A wire of lenght l and resistance r is stretched so that the length is doubled and the srea of cross section is halved .How will its resistance and resistivity change

Answer 1

Answer:

It's resistivity will be unchanged as it is a material dependent property. The resistance of the wire will be of 4 times the previous..

Answer 2

Answer:

the length is doubled

the area of cross section is halfed .

when resistivity is constant ... the resistance will be 1/4th of the previous one