Question

Calculate the resistance of a metal wire of length 5 metres and having an area of cross-section
1.25 x 10-6 m², if the resistivity of the metal is 2.6 x 10-8 m.
[Ans.: 0.1 ohm]​

Answer 1

Length = 5m

Area of cross section = 1.25×10^-6 m²

Resistivity = 2.6×10^-8 m

Resistance = rho×l/A

=>2.6×10^-8 × 5 / 1.25×10^-6

=>13×10^-8/ 1.25×10^-6

=>13×10^-8 × 10^6/1.25

=>13× 10-² /1.25

=>10.4/10²

=>0.014 ~ 0.1Ω

And hence the answer is 0.1Ω

Cheers!