A cylindrical wire is compressed in length by 10%. The
percentage decrease in the resistance will be?????
Answer Posted / aamir ali
Wire is compressed it means volume will be constant (V= Area
x Length) if length is decreased by 10% then area will
increase by 10% (Because volume is constant) suppose
l=length, a=area R=Resistance p=rho, Then R=p*(l/a)
Now if length is compressed by 10% then length=0.9*l and
area=1.1*a
Resistance=p*(.9l/1.1a)=0.8R
This means that Resistance will be decreased by 20%
Hope I answered your Question
Is This Answer Correct ? | 15 Yes | 24 No |
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