A wire 1 m long has a resistances of 1Ω. If it is uniformly stretched so that its length increases by 25%, then what is its increase in resistance?
56.25%
Volume = L×A = Constant = LNew×ANew
LNew = 1 + 25100~=~1.25L\)
L×A=1.25L×ANew
As R = ρLA
Final resistance = 1.252R = 1.5625R\)
Increase = Final resistance - Initial resistance = 0.5625R
Therefore, Increase in Resistance = 56.25%