Question

Find the resistivity of a given wire of radius 2 mm when the length is given as 15 m and resistance of the wire is 30 ohms

Answer 1

Answer:

R = resistivity × length / area

resistivity = R × A / L

= 30 × π ( 2 )^2 / 15 = 2 × π × 4 × 10^-6

= 8π × 10^-6