Question

the resistance permetre length of a wire is 10 ohm.if the resistivity of the material of the wire is 50*10^-8 ohm metre find the area of cross section of the wire​

Answer 1

Hello there

Resistance is the product of resistivity and lenght per unit cross section area.

R = ρ l / A

Given that,

R / l = 10 Ω

ρ = 50×10^-8

Area = ?

R / l = ρ / A

10 = 50×10^-8 / A

A = 50×10^-9

Hence the area of the cross section of the wire will be 50 nm