Question

A long straight wire of length l( a) is made of two concentric conducting materials. The material of the inner tube for radius r ≤ a has a resistivity rho1. The material of the outer shell for radius a < r ≤ 2a has a resistivity rho2. The wire carries a total current I. (a) What is the total resistance R of the conducting wire.

Answer 1

Answer: R = rho/8api or

( rho2-rho1)/8pi

Explanation: you can substitute for rho = rh2 - rho1

Please find the attached file for the solution