Question

a wire is 1.0 mm long 0.2 mm in diameter and has a resistance of 10 ohm calculate the resistivity of its material​

Answer 1

given

lenght = 1mm

diameter = 2mm

radius = 2/2= 1 mm

resistance = 10 ohm

to find resistivity

solution

R= rho l/a  ( a = area of the crosss section )

( rho = resistivity)

rho = Ra/l

      = 10 *3.14 * 1*1/1 ( area of circle =  pi * radius ^2)

    = 31.4 ohm meter

resistivity =  31.4 ohm meter

hope it is correct!!!