Question

What will be the resistance of a metal wire of length 2 metres and area of cross-section 1.55 × 10⁻⁶ m² if the resistivity of the metal be 2.8 × 10⁻⁸ Ω m?

Answer 1

Length of the cable wire, l = 2 m
Area of cross-section, A = 1.55 × 10⁻⁶ m²

Resistivity of the cable wire  ,/2m 

Area of cross-section, `A= 1.55xx10^6m^2` 

Resisitivity of the aluminium cable wire, `rho=2.8xx10^8`Ωm 

 

 

We know that:  

`R=rho/A` 

`R=(2.8xx10^-8xx2)/(1.55xx10^-6)`

 

R = 0.036 Ω

Thus, the resistance of the metal wire, R = 0.036 Ω