1. The problem statement, all variables and given/known data A wire is lengthened to 1.25 times its original length by pulling it through a small hole. Find the resistance of the wire after it is stretched. 2. Relevant equations resistance=(resistivity)(length)/(area) 3. The attempt at a solution Umm..the reasoning behind this is that the initial area times length should equal the final area times length. However, I am not sure why this "conservation of volume" applies. Is it because the current is constant so the volume must remain constant? What does it mean pulling it through a small hole?