Question

Find resistivity of a metallic wire of resistance 10 Ω, length 10 m and radius of cross section as 0.1 mm

Answer 1

Explanation:

we know that resistivity(ρ)=RA/l

where R=resistance

A=cross section area

l=length of wire

so cross section area of wire = πr²

ρ=R.π.r²/l

ρ=10×3.14×(10^-4)²/10

ρ=3.14×10^-8Ω−m