Question

A wire is 1.0 m long,0.2mm diameter and has a 10 ohms . Find the resistivity ?

Answer 1

R = ρL / A

ρ = RA / L
= (10 Ω × π × (0.2/2 × 10^-3 m)^2) / (1 m)
= 3.141 × 10^-7 Ω.m

Resistivity of material is 3.141 × 10^-7 Ω.m

Answer 2

Hey there!

Given,

Length(l) = 1 m

Diameter(d) = 0.2 mm

Radius(r) = 0.1 mm or 0.001 m

Resistance(R) = 10 Ω

Now,

 Area =πr²

         = 3.14 × 0.001 × 0.001

         = 0.00000314 m²

We know,

Resistivity = RA/l

                = 10 × 0.00000314/1

                = 0.0000314 Ω m

                = 3.14×10^-7 Ω m

Hope It Helps You!